Clinical Focus

  • Diagnostic Radiology
  • Radiology
  • Musculoskeletal Abnormalities

Academic Appointments

  • Associate Professor - University Medical Line, Radiology

Administrative Appointments

  • Trauma Division Quality Improvement Committee, Stanford University School of Medicine (2002 - 2010)
  • Liaison Committee, International Skeletal Society (2009 - 2010)
  • Director of Musculoskeletal Education, Department of Radiology (2009 - Present)
  • Ad Hoc Program Committee, International Skeletal Society (2012 - 2013)
  • Ad Hoc Program Committee, International Skeletal Society (2012 - 2013)
  • Scientific Program Committee, International Skeletal Society (2013 - 2015)
  • Educational Exhibit Committee, Radiologic Society of North America (2015 - 2015)
  • Scientific program committee, International Society of Skeletal Radiology (2015 - 2017)
  • Adjunct Clinical Faculty A&P committee, Stanford University School of Medicine (2015 - 2018)
  • Faculty Search Committee for Clinical Chest Radiologist, Stanford Radiology (2016 - Present)
  • Chairman, Adjunct Clinical Faculty A&P committee, Stanford University School of Medicine (2018 - Present)
  • Diversity Committee, Stanford Radiology (2018 - Present)
  • Faculty Search Committee for musculoskeletal Imaging PhD, Stanford Radiology (2018 - Present)
  • Faculty Search Committee for Clinical MSK Radiologist, Stanford Radiology (2019 - Present)
  • Chairman Membership Committee, International Skeletal Society (2020 - Present)
  • Faculty Ad Hoc Committee, Stanford Radiology (2021 - Present)
  • Rolling Faculty Search Committee for Pediatric Radiologists, Stanford Radiology (2022 - 2024)
  • Faculty Search Committee for Clinical MSK Radiologist, Stanford Radilogy (2022 - Present)
  • Radiology Wellbeing Committee, Stanford Radiology (2022 - Present)
  • Faculty Search Committee for MSK section chief, Stanford Radiology (2023 - 2024)
  • DEI Committee, International Skeletal Society (2023 - Present)
  • Director of Ultrasound, Stanford Radiology Division of MSK Imaging (2023 - Present)
  • ISS Include Latin America Working Group, International Skeletal Society (2023 - Present)
  • MSK Scholarly Optimization Team, Stanford Radiology Division of MSK Imaging (2023 - Present)
  • Membership Committee, Society of Skeletal Radiology (2023 - Present)
  • Scholarly Opportunities Committee, Stanford Radiology Division of MSK Imaging (2023 - Present)
  • White paper panel on meniscal lesions, Society of Skeletal Radiology (2023 - Present)
  • Faculty Search Committee for Clinical Educator, MSK Division, Stanford Radiology (2024 - Present)

Honors & Awards

  • McCowan Entrance Scholarship, St Mary's Hospital Medical School (1983)
  • War Memorial Leaving Scholarship, City of London School (1983)
  • Annual Histology Prize, St Mary's Hospital Medical School (1984)
  • Martin Clinical Scholarship, St Mary's Hospital Medical School (1986)
  • Distinction in Pathology, St Mary's Hospital Medical School (1988)
  • Anthony de Rothschild Prize in Surgery, St Mary's Hospital Medical School (1989)
  • Distinction in Clinical Pharmacology and Therapeutics, St Mary's Medical School (1989)
  • Distinction in Obstetrics and Gynaecology, St Mary's Medical School (1989)
  • Distinction in Surgery, St Mary's Medical School (1989)
  • ICI Pharmaceuticals Prize, St Mary's Hospital Medical School (1989)
  • Meadows Prize in Obstetrics and Gynaecology, St Mary's Medical School (1989)
  • Morris Clinical Project Prize, St Mary's Hospital Medical School (1989)
  • University of London Gold Medal, University of London (1989)
  • Conrad Lewin Prize, British British Association of Clinical Anatomy (1996)
  • Kodak Radiology Fund Bursary, Royal College of Radiologists (1999)
  • Wishbone trust grant, Oxford University (1999)
  • Dr Karol Sicher Cancer Research Fellowship, Royal College of Radiologists (2000)
  • Stanford University Dean's Fellowship, Stanford University (2000)
  • Certificate of Merit, American Roentgen Ray Society (2005)
  • Cum Laude Award, Society of Computed Body Tomography and Magnetic Resonance (2007)
  • Certificate of Merit, RSNA (2009)
  • Junior faculty of the year, Stanford Radiology (2009)
  • Certificate of Merit, RSNA (2010)
  • Magna Cum Laude Merit Award, ISMRM (2017)
  • 2nd “Best Science” Presentation, ISMRM and RSNA Workshop on Value in MRI (2018)
  • 2nd “Best Value” Presentation, ISMRM and RSNA Workshop on Value in MRI (2018)
  • Best Healthcare Poster and Best Poster overall, NVIDIA GPU Technology Conference, San Jose (2018)
  • Magna Cum Laude Merit Award, ISMRM (2018)
  • Cum Laude Award, RSNA (2019)
  • Magna Cum Laude Merit Award, ISMRM (2019)
  • Summa Cum Laude Merit Award, ISMRM (2019)
  • Bronze medal, ARRS (2020)
  • Certificate of Merit, ARRS (2020)
  • Runner up prize for Educational Exhibit Award, SSR (2021)
  • Award for the case with the most laughter, OCAD (2022)
  • Certificate of Merit, RSNA (2022)
  • Department of Archeology and Natural History Award, SSR (2022)
  • Kardashian Award, SSR (2022)
  • AIRP Award for Best Poster, Society of Skeletal Radiology (2023)
  • Certificate of Merit, ARRS (2023)
  • Certificate of Merit, ARRS (2024)
  • Magna cum laude, ARRS (2024)

Professional Education

  • Board Certification: Royal College of Radiologist, Diagnostic Radiology (1997)
  • Internship: Royal United Hospital NHS Trust (1990) United Kingdom
  • Fellowship: Nuffield Orthopaedic Centre (1999) England
  • Residency: Nottingham Hospitals (1998) England
  • Residency: Nottingham Hospitals (1994) England
  • Medical Education: St Mary's Hospital Medical School (1989) England
  • FRCR, Royal College of Radiologists, Radiology (1997)
  • MB BS, London University, Medicine (1989)
  • BSc (hons), London University, Biochemistry/ Chemical Pathology (1986)

Current Research and Scholarly Interests

Sports medicine - imaging of sports injuries in athletes and ultrasound-guided therapy.

Clinical applications of new MRI pulse sequences.

Metal suppression MRI around orthopedic implants.

Imaging and guided therapy in rheumatology.

2023-24 Courses

All Publications

  • Clinical evaluation of isotropic MAVRIC-SL for symptomatic hip arthroplasties at 3 T MRI. Magnetic resonance imaging Yoon, D., Doyle, Z., Lee, P., Hargreaves, B., Stevens, K. 2024


    3D multi-spectral imaging (MSI) of metal implants necessitates relatively long scan times.We implemented a fast isotropic 3D MSI technique at 3 T and compared its image quality and clinical utility to non-isotropic MSI in the evaluation of hip implants.Two musculoskeletal radiologists scored images from coronal proton density-weighted conventional MAVRIC-SL and an isotropic MAVRIC-SL sequence accelerated with robust-component-analysis on a 3-point scale (3: diagnostic, 2: moderately diagnostic, 1: non-diagnostic) for overall image quality, metal artifact, and visualization around femoral and acetabular components. Grades were compared using a signed Wilcoxon test. Images were evaluated for effusion, synovitis, osteolysis, loosening, pseudotumor, fracture, and gluteal tendon abnormalities. Reformatted axial and sagittal images for both sequences were subsequently generated and compared for image quality with the Wilcoxon test. Whether these reformats increased diagnostic confidence or revealed additional pathology, including findings unrelated to arthroplasty that may contribute to hip pain, was also compared using the McNemar test. Inter-rater agreement was measured by Cohen's kappa.39 symptomatic patients with a total of 59 hip prostheses were imaged (mean age, 70 years ±9, 14 males, 25 females). Comparison scores between coronal images showed no significant difference in image quality, metal artifact, or visualization of the femur and acetabulum. Except for loosening, reviewers identified more positive cases of pathology on the original coronally-acquired isotropic sequence. In comparison of reformatted axial and sagittal images, the isotropic sequence scored significantly (p < 0.01) higher for overall image quality (3.0 vs 2.0) and produced significantly (p < 0.01) more cases of increased diagnostic confidence (42.4% vs 7.6%) or additional diagnoses (50.8% vs 22.9%). Inter-rater agreement was substantial (k = 0.798) for image quality. Mean scan times were 4.2 mins (isotropic) and 7.1 mins (non-isotropic).Compared to the non-isotropic sequence, isotropic 3D MSI was acquired in less time while maintaining diagnostically acceptable image quality. It identified more pathology, including postoperative complications and potential pain-generating pathology unrelated to arthroplasty. This fast isotropic 3D MSI sequence demonstrates promise for improving diagnostic evaluation of symptomatic hip prostheses at 3 T while simultaneously reducing scan time.

    View details for DOI 10.1016/j.mri.2024.04.017

    View details for PubMedID 38621551

  • Differences in Anatomic Adaptation and Injury Patterns Related to Valgus Extension Overload in Overhead Throwing Athletes. Diagnostics (Basel, Switzerland) Stevens, K. J., Chaudhari, A. S., Kuhn, K. J. 2024; 14 (2)


    The purpose of our study was to determine differences in adaptative and injury patterns in the elbow related to valgus extension overload (VEO) in overhead throwing athletes by age. A total of 86 overhead throwing athletes and 23 controls underwent MRI or MR arthrography (MRA) of the elbow. Throwing athletes were divided by age into three groups: ≤16 years (26 subjects), 17-19 years (25 subjects), and ≥20 years (35 subjects). Consensus interpretation of each MRI was performed, with measurements of ulnar collateral ligament (UCL) thickness and subchondral sclerosis at the radial head, humeral trochlea, and olecranon process. A higher frequency of apophyseal and stress injuries was seen in adolescent athletes and increased incidence of soft tissue injuries was observed in older athletes. Early adaptive and degenerative changes were observed with high frequency independent of age. Significant differences were observed between athletes and controls for UCL thickness (p < 0.001) and subchondral sclerosis at the radial head (p < 0.001), humeral trochlea (p < 0.001), and olecranon process (p < 0.001). Significant differences based on athlete age were observed for UCL thickness (p < 0.001) and subchondral sclerosis at the olecranon process (p = 0.002). Our study highlights differences in anatomic adaptations related to VEO at the elbow between overhead throwing athletes and control subjects, as well as across age in throwing athletes.

    View details for DOI 10.3390/diagnostics14020217

    View details for PubMedID 38275464

  • Imaging findings of arterial calcification due to deficiency of CD73: A case study JOURNAL OF RADIOLOGY CASE REPORTS Mandalapu, A., Stevens, K. J. 2023; 17 (11): 27-33
  • Artificial Intelligence System for Automatic Quantitative Analysis and Radiology Reporting of Leg Length Radiographs. Journal of digital imaging Larson, N., Nguyen, C., Do, B., Kaul, A., Larson, A., Wang, S., Wang, E., Bultman, E., Stevens, K., Pai, J., Ha, A., Boutin, R., Fredericson, M., Do, L., Fang, C. 2022


    Leg length discrepancies are common orthopedic problems with the potential for poor functional outcomes. These are frequently assessed using bilateral leg length radiographs. The objective was to determine whether an artificial intelligence (AI)-based image analysis system can accurately interpret long leg length radiographic images. We built an end-to-end system to analyze leg length radiographs and generate reports like radiologists, which involves measurement of lengths (femur, tibia, entire leg) and angles (mechanical axis and pelvic tilt), describes presence and location of orthopedic hardware, and reports laterality discrepancies. After IRB approval, a dataset of 1,726 extremities (863 images) from consecutive examinations at a tertiary referral center was retrospectively acquired and partitioned into train/validation and test sets. The training set was annotated and used to train a fasterRCNN-ResNet101 object detection convolutional neural network. A second-stage classifier using a EfficientNet-D0 model was trained to recognize the presence or absence of hardware within extracted joint image patches. The system was deployed in a custom web application that generated a preliminary radiology report. Performance of the system was evaluated using a holdout 220 image test set, annotated by 3 musculoskeletal fellowship trained radiologists. At the object detection level, the system demonstrated a recall of 0.98 and precision of 0.96 in detecting anatomic landmarks. Correlation coefficients between radiologist and AI-generated measurements for femur, tibia, and whole-leg lengths were>0.99, with mean error of<1%. Correlation coefficients for mechanical axis angle and pelvic tilt were 0.98 and 0.86, respectively, with mean absolute error of<1°. AI hardware detection demonstrated an accuracy of 99.8%. Automatic quantitative and qualitative analysis of leg length radiographs using deep learning is feasible and holds potential in improving radiologist workflow.

    View details for DOI 10.1007/s10278-022-00671-2

    View details for PubMedID 35794502

  • Change in calcinosis over 1 year using the scleroderma clinical trials consortium radiologic scoring system for calcinosis of the hands in patients with systemic sclerosis. Seminars in arthritis and rheumatism Valenzuela, A., Stevens, K., Chung, M. P., Rodriguez-Reyna, T. S., Proudman, S., Baron, M., Castelino, F. V., Hsu, V., Green, L., Galdo, F. D., Li, S., Fiorentino, D., Chung, L. 2022; 53: 151980


    INTRODUCTION: Calcinosis cutis is a debilitating complication of systemic sclerosis (SSc). We previously developed a radiographic scoring system to assess severity of calcinosis affecting the hands in patients with SSc. We sought to further validate our radiographic scoring system to assess for change over 1 year and to identify factors associated with improvement or progression.MATERIALS AND METHODS: Baseline and 1-year antero-posterior hand radiographs were obtained in 39 SSc patients with calcinosis prospectively enrolled at 6 centers within the US, Canada, Mexico and Australia. Two readers (one radiologist and one rheumatologist) scored all radiographs using the calcinosis scoring system and a 5-point Likert scale (1=A lot better, 2=A little better, 3=No change, 4=A little worse, 5=A lot worse) on follow-up. By maximizing the Kappa coefficient of agreement between grouped Likert scale (better/no change/worse) and the percentage of change of calcinosis in the radiographic scoring system, we defined progressive calcinosis as >25% increase in score from baseline at 1-year, stable calcinosis as change in score between -25% to 25%, and improvement of calcinosis as decrease in score by >25%. Nineteen SSc patients from an independent cohort were used for validation.RESULTS: Inter-rater reliability of the calcinosis scoring system was high with intra-class correlation coefficient of 0.93 (0.89-0.95). The median percentage of change from baseline to 1 year was 12.8% (range -89.3 to 290.2%). Sixteen patients (41%) experienced progression of calcinosis over 1 year; 18 (46%) remained stable; and 5 (13%) had improvement. Patients with progressive calcinosis had lower T-score on bone densitometry (-3.3vs -1.7, p=0.044) and higher prevalence of loss of digital pulp on physical exam (56% vs 22%, p=0.027), with a trend towards lower baseline modified Rodnan skin score (mRSS) (3.8vs. 5.9, p=0.057), than patients who did not progress. Patients who experienced improvement in calcinosis had lower prevalence of digital pitting scars (20% vs 71%, p=0.047) than patients whose calcinosis did not improve. In multivariable analysis, loss of digital pulp remained a predictor of calcinosis progression (OR 5.8, p=0.023, CI 1.27 - 26.36). In the validation cohort, 2 (11%) patients improved, 10 (53%) remained stable, and 7 (37%) progressed.CONCLUSIONS: We confirmed the excellent inter-rater reliability of our radiographic calcinosis scoring system and demonstrated its usefulness to detect change over time. Approximately 40% of patients experienced progression of calcinosis over 1 year. Loss of digital pulp was predictive of progressive calcinosis providing further evidence that digital ischemia contributes to the progression of calcinosis.

    View details for DOI 10.1016/j.semarthrit.2022.151980

    View details for PubMedID 35183935

  • Automating Scoliosis Measurements in Radiographic Studies with Machine Learning: Comparing Artificial Intelligence and Clinical Reports. Journal of digital imaging Ha, A. Y., Do, B. H., Bartret, A. L., Fang, C. X., Hsiao, A., Lutz, A. M., Banerjee, I., Riley, G. M., Rubin, D. L., Stevens, K. J., Wang, E., Wang, S., Beaulieu, C. F., Hurt, B. 2022


    Scoliosis is a condition of abnormal lateral spinal curvature affecting an estimated 2 to 3% of the US population, or seven million people. The Cobb angle is the standard measurement of spinal curvature in scoliosis but is known to have high interobserver and intraobserver variability. Thus, the objective of this study was to build and validate a system for automatic quantitative evaluation of the Cobb angle and to compare AI generated and human reports in the clinical setting. After IRB was obtained, we retrospectively collected 2150 frontal view scoliosis radiographs at a tertiary referral center (January 1, 2019, to January 1, 2021, ≥ 16 years old, no hardware). The dataset was partitioned into 1505 train (70%), 215 validation (10%), and 430 test images (20%). All thoracic and lumbar vertebral bodies were segmented with bounding boxes, generating approximately 36,550 object annotations that were used to train a Faster R-CNN Resnet-101 object detection model. A controller algorithm was written to localize vertebral centroid coordinates and derive the Cobb properties (angle and endplate) of dominant and secondary curves. AI-derived Cobb angle measurements were compared to the clinical report measurements, and the Spearman rank-order demonstrated significant correlation (0.89, p < 0.001). Mean difference between AI and clinical report angle measurements was 7.34° (95% CI: 5.90-8.78°), which is similar to published literature (up to 10°). We demonstrate the feasibility of an AI system to automate measurement of level-by-level spinal angulation with performance comparable to radiologists.

    View details for DOI 10.1007/s10278-022-00595-x

    View details for PubMedID 35149938

  • Elbow Imaging: Variants and Asymptomatic Findings. Seminars in musculoskeletal radiology Antil, N., Stevens, K. J., Lutz, A. M. 2021; 25 (4): 546-557


    One of the key principles in the interpretation of radiology images is the ability to differentiate between normal and abnormal findings. This article provides a comprehensive overview of normal structures and anatomical variants occurring around the elbow including potential diagnostic pitfalls. We discuss frequently observed anatomical variants found in routine clinical practice associated with osseous, ligamentous, musculotendinous, and neurovascular structures at the elbow that may simulate pathology or predispose to symptoms under specific circumstances.

    View details for DOI 10.1055/s-0041-1729960

    View details for PubMedID 34706384

  • Clinical utility of accelerated MAVRIC-SL with robust-PCA compared to conventional MAVRIC-SL in evaluation of total hip arthroplasties. Skeletal radiology Doyle, Z., Yoon, D., Lee, P. K., Rosenberg, J., Hargreaves, B. A., Beaulieu, C. F., Stevens, K. J. 2021


    OBJECTIVE: To compare the diagnostic performance of a conventional metal artifact suppression sequence MAVRIC-SL (multi-acquisition variable-resonance image combination selective) and a novel 2.6-fold faster sequence employing robust principal component analysis (RPCA), in the MR evaluation of hip implants at 3T.MATERIALS AND METHODS: Thirty-six total hip implants in 25 patients were scanned at 3T using a conventional MAVRIC-SL proton density-weighted sequence and an RPCA MAVRIC-SL proton density-weighted sequence. Comparison was made of image quality, geometric distortion, visualization around acetabular and femoral components, and conspicuity of abnormal imaging findings using the Wilcoxon signed-rank test and a non-inferiority test. Abnormal findings were correlated with subsequent clinical management and intraoperative findings if the patient underwent subsequent surgery.RESULTS: Mean scores for conventional MAVRIC-SL were better than RPCA MAVRIC-SL for all qualitative parameters (p<0.05), although the probability of RPCA MAVRIC-SL being clinically useful was non-inferior to conventional MAVRIC-SL (within our accepted 10% difference, p<0.05), except for visualization around the acetabular component. Abnormal imaging findings were seen in 25 hips, and either equally visible or visible but less conspicuous on RPCA MAVRIC-SL in 21 out of 25 cases. In 4 cases, a small joint effusion was queried on MAVRIC-SL but not RPCA MAVRIC-SL, but the presence or absence of a small effusion did not affect subsequent clinical management and patient outcome.CONCLUSION: While the overall image quality is reduced, RPCA MAVRIC-SL allows for significantly reduced scan time and maintains almost equal diagnostic performance.

    View details for DOI 10.1007/s00256-021-03848-y

    View details for PubMedID 34223946

  • Non-contrast MRI of synovitis in the knee using quantitative DESS. European radiology Thoenen, J., Stevens, K. J., Turmezei, T. D., Chaudhari, A., Watkins, L. E., McWalter, E. J., Hargreaves, B. A., Gold, G. E., MacKay, J. W., Kogan, F. 2021


    OBJECTIVES: To determine whether synovitis graded by radiologists using hybrid quantitative double-echo in steady-state (qDESS) images can be utilized as a non-contrast approach to assess synovitis in the knee, compared against the reference standard of contrast-enhanced MRI (CE-MRI).METHODS: Twenty-two knees (11 subjects) with moderate to severe osteoarthritis (OA) were scanned using CE-MRI, qDESS with a high diffusion weighting (qDESSHigh), and qDESS with a low diffusion weighting (qDESSLow). Four radiologists graded the overall impression of synovitis, their diagnostic confidence, and regional grading of synovitis severity at four sites (suprapatellar pouch, intercondylar notch, and medial and lateral peripatellar recesses) in the knee using a 4-point scale. Agreement between CE-MRI and qDESS, inter-rater agreement, and intra-rater agreement were assessed using a linearly weighted Gwet's AC2.RESULTS: Good agreement was seen between CE-MRI and both qDESSLow (AC2=0.74) and qDESSHigh (AC2=0.66) for the overall impression of synovitis, but both qDESS sequences tended to underestimate the severity of synovitis compared to CE-MRI. Good inter-rater agreement was seen for both qDESS sequences (AC2=0.74 for qDESSLow, AC2=0.64 for qDESSHigh), and good intra-rater agreement was seen for both sequences as well (qDESSLow AC2=0.78, qDESSHigh AC2=0.80). Diagnostic confidence was moderate to high for qDESSLow (mean=2.36) and slightly less than moderate for qDESSHigh (mean=1.86), compared to mostly high confidence for CE-MRI (mean=2.73).CONCLUSIONS: qDESS shows potential as an alternative MRI technique for assessing the severity of synovitis without the use of a gadolinium-based contrast agent.KEY POINTS: The use of the quantitative double-echo in steady-state (qDESS) sequence for synovitis assessment does not require the use of a gadolinium-based contrast agent. Preliminary results found that low diffusion-weighted qDESS (qDESSLow) shows good agreement to contrast-enhanced MRI for characterization of the severity of synovitis, with a relative bias towards underestimation of severity. Preliminary results also found that qDESSLow shows good inter- and intra-rater agreement for the depiction of synovitis, particularly for readers experienced with the sequence.

    View details for DOI 10.1007/s00330-021-08025-2

    View details for PubMedID 33993332

  • A narrative review of imaging in calcinosis associated with systemic sclerosis. Clinical rheumatology Mar, D., Valenzuela, A., Stevens, K. J., Chung, L., Fairchild, R. M. 2021


    Calcinosis is dystrophic calcification of the soft tissue which can lead to painful and debilitating disease. It is commonly seen in patients with systemic sclerosis (SSc). Imaging can assist in diagnosis, quantification of disease, and better pathophysiologic understanding of calcinosis. Traditionally, X-rays have been the most frequently used imaging modality for diagnosis; however, advances in ultrasound (US), computed tomography (CT), positron emission tomography (PET), and magnetic resonance imaging (MRI) have led to greater ability to characterize these lesions and surrounding structures. This narrative review aims to describe the use of imaging for calcinosis in patients with SSc. Key Points Imaging is useful in the diagnosis of calcinosis, assessment of disease severity, and disease monitoring. X-ray is commonly used and offers high sensitivity and specificity, but both ultrasound and CT-scans are alternatives when greater anatomic detail is sought regarding surrounding structures. Investigational imaging modalities include dual energy CT-scans, cinematic rendering CT-scans, and PET- CT scans. Conventional MRI scans have less sensitivity and specificity for detection of calcinosis.

    View details for DOI 10.1007/s10067-021-05696-6

    View details for PubMedID 33755836

  • A Pilot Study to Evaluate the Safety and Efficacy of Treprostinil in the Treatment of Calcinosis in Systemic Sclerosis. Rheumatology (Oxford, England) Chung, M. P., Valenzuela, A., Li, S., Catanese, B., Stevens, K., Fiorentino, D., Strand, V., Chung, L. 2021


    We evaluated the safety and efficacy of oral treprostinil in preventing progression of SSc-associated calcinosis.This prospective open-label study enrolled 12 SSc patients meeting 2013 ACR/EULAR classification criteria with confirmed clinical and radiographic evidence of ≥ 1 calcinosis deposit in the hands. Patients received oral treprostinil for 1 year. Primary endpoints were safety/tolerability and percentage of patients without radiographic progression of calcinosis at 1 year (<25% increase in Scleroderma Clinical Trials Consortium radiographic score). Secondary endpoints included 1-year changes in Scleroderma HAQ (SHAQ), Cochin Hand Functional Scale, Medical Outcomes Survey Short Form 36 (SF-36), Raynaud Condition Score, and patient/physician assessment of calcinosis severity.Twelve female patients were enrolled, half with diffuse cutaneous disease; median age was 55 (range 35-68) years. Five patients completed the study. Seven patients withdrew due to intolerable adverse effects (n = 3), intercurrent unrelated illness (n = 2, cirrhosis, cancer), progressive SSc (n = 1), and personal reasons (n = 1). Most patients developed headaches and gastrointestinal adverse effects. Four of 11 (36%) patients with 1-year follow-up hand radiographs experienced progression of calcinosis. Of 5 who completed treatment, calcinosis was stable in 4 (80%) with progression in 1. Based on SF-36 Physical (PCS) and Mental (MCS) Component and Domain scores, transition question, and SF-6D utility score, all patients who finished the trial reported overall improvement or no change compared with baseline.Oral treprostinil was poorly tolerated in SSc patients with calcinosis. Of 5 patients who completed treatment, most (80%) had documented stability of calcinosis on hand radiographs at 1 year.NCT02663895.

    View details for DOI 10.1093/rheumatology/keab810

    View details for PubMedID 34718447

  • A Pilot Study to Evaluate the Safety and Efficacy of Treprostinil in the Treatment of Calcinosis in Patients with Systemic Sclerosis Chung, M., Valenzuela Vergara, A., Catanese, B., Li, S., Stevens, K., Chung, L. WILEY. 2020
  • Diagnostic Accuracy of Quantitative Multi-Contrast 5-Minute Knee MRI Using Prospective Artificial Intelligence Image Quality Enhancement. AJR. American journal of roentgenology Chaudhari, A. S., Grissom, M. J., Fang, Z. n., Sveinsson, B. n., Lee, J. H., Gold, G. E., Hargreaves, B. A., Stevens, K. J. 2020


    Potential approaches for abbreviated knee MRI, including prospective acceleration with deep learning, have achieved limited clinical implementation to date.The objective of this study was to evaluate the inter-reader agreement of conventional knee MRI and a 5-minute 3D quantitative double-echo steady-state (qDESS) sequence with automatic T2 mapping and deep-learning super-resolution (DLSR) augmentation, as well as to compare the diagnostic performance of the two methods with respect to findings from arthroscopic surgery.A total of 51 patients with knee pain underwent knee MRI that included an additional 3D qDESS sequence with automatic T2 mapping. Fourier interpolation was followed by prospective DLSR to enhance qDESS slice-resolution twofold. A musculoskeletal radiologist and a radiology resident performed retrospective independent evaluations of the articular cartilage, menisci, ligaments, bones, extensor mechanism, and synovium using conventional MRI. Following a two-month washout period, the readers reviewed qDESS images alone, followed by qDESS with the automatic T2 maps. Inter-reader agreement between conventional MRI and qDESS was computed using percent agreement and Cohen's Kappa. The sensitivity and specificity of conventional MRI, qDESS alone, and qDESS+T2 were compared with arthroscopic findings using exact McNemar's tests.Conventional MRI and qDESS demonstrated 92% agreement in evaluation of articular cartilage, menisci, ligaments, bones, extensor mechanism, and synovium combined. Kappa was 0.79 (0.76-0.81) across all imaging findings. In the 43/51 patients who underwent arthroscopy, sensitivity and specificity were not significantly different (p=0.23-1.00) between conventional MRI (sensitivity: 58%-93%; specificity: 27%-87%) and qDESS alone (sensitivity: 54%-90%; specificity: 23%-91%) for cartilage, menisci, ligaments, and synovium. Sensitivity and specificity for grade 1 cartilage lesions were 33%/56% for conventional MRI, 23%/53% for qDESS (p=0.81), and 46%/39% for qDESS+T2 (p=0.80); for grade 2A lesions, 27%/53% for conventional MRI, 26%/52% for qDESS (p=0.02), and 58%/40% for qDESS+T2 (p<0.001).qDESS prospectively enhanced with deep learning had strong inter-reader agreement with conventional knee MRI and near-equivalent diagnostic performance with respect to arthroscopy. The ability of qDESS to automatically generate T2 maps increases sensitivity for cartilage abnormalities. Clinical Impact: qDESS using prospective artificial intelligence image quality enhancement may facilitate an abbreviated knee MRI protocol while generating quantitative T2 maps.

    View details for DOI 10.2214/AJR.20.24172

    View details for PubMedID 32755384

  • Comprehensive Update of Elbow Magnetic Resonance Imaging. Current problems in diagnostic radiology Porrino, J. n., Wang, A. n., Taljanovic, M. n., Stevens, K. J. 2020


    We present a comprehensive update of elbow magnetic resonance imaging, detailing the complex anatomy and pathology of the elbow. A variety of pathologies may affect the elbow joint, and many of the symptoms overlap. As such, magnetic resonance imaging of the elbow serves as an invaluable clinical tool for the clinician in the diagnosis and management of patients presenting with elbow pain.

    View details for DOI 10.1067/j.cpradiol.2020.04.011

    View details for PubMedID 32561154

  • The Stieda fracture revisited. Skeletal radiology Stevens, K. J., Albtoush, O. M., Lutz, A. M. 2020


    This study aimed to evaluate injury patterns associated with Stieda avulsion fractures of the medial femoral condyle at the attachment of the proximal MCL.Knee radiographs and MRI scans of 11 patients with Stieda fractures were evaluated by two fellowship-trained MSK radiologists for fracture origin, integrity of the deep and superficial components of the MCL, medial retinacular structures, posterior oblique ligament, other ligamentous injuries, meniscal tears, and osteochondral injuries. The mechanism of injury and subsequent clinical management were recorded.Eight Stieda fractures only involved the meniscofemoral fibers of the deep MCL, two larger Stieda fractures related to both superficial and deep layers, and one fracture only involved the superficial layer. Posteromedial retinacular structures and posterior oblique ligament were injured in all cases. Eight had high-grade ACL injuries, but none had high-grade PCL nor FCL injuries. The proximal anterolateral ligament was injured in seven, including two with associated Segond fractures. Other injuries included posterolateral corner injuries in six, meniscal injuries in seven, and additional fractures in nine, most commonly ACL-associated impaction fractures in the lateral tibiofemoral compartment. None had high-grade chondral injury. None of the Stieda fractures were treated surgically, but four underwent subsequent ACL reconstruction.Stieda fractures most commonly involved the deep fibers of the MCL and were accompanied by moderate-to-high-grade injury of other MCL components. There was a high association with other ligamentous injuries, particularly the posterior medial retinacular structures, posterior oblique ligament, and ACL, and many were associated with additional fractures.

    View details for DOI 10.1007/s00256-020-03645-z

    View details for PubMedID 33034705

  • Change in Calcinosis over 1 Year Using the SCTC Radiologic Scoring System for Calcinosis of the Hands in Patients with Systemic Sclerosis Valenzuela, A., Chung, M., Rodriguez-Reyna, T. S., Proudman, S., Baron, M., Castelino, F., Hsu, V., Li, S., Fiorentino, D., Stevens, K., Chung, L. WILEY. 2019
  • Utility of deep learning super-resolution in the context of osteoarthritis MRI biomarkers. Journal of magnetic resonance imaging : JMRI Chaudhari, A. S., Stevens, K. J., Wood, J. P., Chakraborty, A. K., Gibbons, E. K., Fang, Z., Desai, A. D., Lee, J. H., Gold, G. E., Hargreaves, B. A. 2019


    BACKGROUND: Super-resolution is an emerging method for enhancing MRI resolution; however, its impact on image quality is still unknown.PURPOSE: To evaluate MRI super-resolution using quantitative and qualitative metrics of cartilage morphometry, osteophyte detection, and global image blurring.STUDY TYPE: Retrospective.POPULATION: In all, 176 MRI studies of subjects at varying stages of osteoarthritis.FIELD STRENGTH/SEQUENCE: Original-resolution 3D double-echo steady-state (DESS) and DESS with 3* thicker slices retrospectively enhanced using super-resolution and tricubic interpolation (TCI) at 3T.ASSESSMENT: A quantitative comparison of femoral cartilage morphometry was performed for the original-resolution DESS, the super-resolution, and the TCI scans in 17 subjects. A reader study by three musculoskeletal radiologists assessed cartilage image quality, overall image sharpness, and osteophytes incidence in all three sets of scans. A referenceless blurring metric evaluated blurring in all three image dimensions for the three sets of scans.STATISTICAL TESTS: Mann-Whitney U-tests compared Dice coefficients (DC) of segmentation accuracy for the DESS, super-resolution, and TCI images, along with the image quality readings and blurring metrics. Sensitivity, specificity, and diagnostic odds ratio (DOR) with 95% confidence intervals compared osteophyte detection for the super-resolution and TCI images, with the original-resolution as a reference.RESULTS: DC for the original-resolution (90.2±1.7%) and super-resolution (89.6±2.0%) were significantly higher (P<0.001) than TCI (86.3±5.6%). Segmentation overlap of super-resolution with the original-resolution (DC = 97.6±0.7%) was significantly higher (P<0.0001) than TCI overlap (DC = 95.0±1.1%). Cartilage image quality for sharpness and contrast levels, and the through-plane quantitative blur factor for super-resolution images, was significantly (P<0.001) better than TCI. Super-resolution osteophyte detection sensitivity of 80% (76-82%), specificity of 93% (92-94%), and DOR of 32 (22-46) was significantly higher (P<0.001) than TCI sensitivity of 73% (69-76%), specificity of 90% (89-91%), and DOR of 17 (13-22).DATA CONCLUSION: Super-resolution appears to consistently outperform naive interpolation and may improve image quality without biasing quantitative biomarkers.LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019.

    View details for DOI 10.1002/jmri.26872

    View details for PubMedID 31313397

  • Combined 5-minute double-echo in steady-state with separated echoes and 2-minute proton-density-weighted 2D FSE sequence for comprehensive whole-joint knee MRI assessment JOURNAL OF MAGNETIC RESONANCE IMAGING Chaudhari, A. S., Stevens, K. J., Sveinsson, B., Wood, J. P., Beaulieu, C. F., Oei, E. G., Rosenberg, J. K., Kogan, F., Alley, M. T., Gold, G. E., Hargreaves, B. A. 2019; 49 (7): E183–E194

    View details for DOI 10.1002/jmri.26582

    View details for Web of Science ID 000474612300018

  • Results from a Phase 1 Study of Sodium Selenite in Combination with Palliative Radiation Therapy in Patients with Metastatic Cancer. Translational oncology Knox, S. J., Jayachandran, P. n., Keeling, C. A., Stevens, K. J., Sandhu, N. n., Stamps-DeAnda, S. L., Savic, R. n., Shura, L. n., Buyyounouski, M. K., Grimes, K. n. 2019; 12 (11): 1525–31


    In preclinical studies, selenite had single agent activity and radiosensitized tumors in vivo. Here we report results from a Phase 1 trial in 15 patients with metastatic cancer treated with selenite (5.5 to 49.5 mg) orally as a single dose 2 hours before each radiation therapy (RT) treatment. Patients received RT regimens that were standard of care. The primary objective of the study was to assess the safety of this combination therapy. Secondary objectives included measurement of pharmacokinetics (PK) and evaluation of efficacy. Endpoints included assessment of PK, toxicity, tumor response, and pain before and after treatment. The half-life of selenite was 18.5 hours. There were no adverse events attributable to selenite until the 33 mg dose level, at which the primary toxicities were grade 1 GI side effects. One patient treated with 49.5 mg had grade 2 GI toxicity. Although this was not a DLT, it was felt that the highest acceptable dose in this patient population was 33 mg. Most patients had stabilization of disease within the RT fields, with some demonstrating objective evidence of tumor regression. Most patients had a marked improvement in pain and seven out of nine patients with prostate cancer had a decrease in PSA ranging from 11-78%. Doses up to 33 mg selenite were well tolerated in combination with RT. A randomized, well controlled study is needed at the 33 mg dose level to determine if selenite results in clinically meaningful improvements in the response to palliative RT.

    View details for DOI 10.1016/j.tranon.2019.08.006

    View details for PubMedID 31454725

  • Combined 5-minute double-echo in steady-state with separated echoes and 2-minute proton-density-weighted 2D FSE sequence for comprehensive whole-joint knee MRI assessment. Journal of magnetic resonance imaging : JMRI Chaudhari, A. S., Stevens, K. J., Sveinsson, B., Wood, J. P., Beaulieu, C. F., Oei, E. H., Rosenberg, J. K., Kogan, F., Alley, M. T., Gold, G. E., Hargreaves, B. A. 2018


    BACKGROUND: Clinical knee MRI protocols require upwards of 15 minutes of scan time.PURPOSE/HYPOTHESIS: To compare the imaging appearance of knee abnormalities depicted with a 5-minute 3D double-echo in steady-state (DESS) sequence with separate echo images, with that of a routine clinical knee MRI protocol. A secondary goal was to compare the imaging appearance of knee abnormalities depicted with 5-minute DESS paired with a 2-minute coronal proton-density fat-saturated (PDFS) sequence.STUDY TYPE: Prospective.SUBJECTS: Thirty-six consecutive patients (19 male) referred for a routine knee MRI.FIELD STRENGTH/SEQUENCES: DESS and PDFS at 3T.ASSESSMENT: Five musculoskeletal radiologists evaluated all images for the presence of internal knee derangement using DESS, DESS+PDFS, and the conventional imaging protocol, and their associated diagnostic confidence of the reading.STATISTICAL TESTS: Differences in positive and negative percent agreement (PPA and NPA, respectively) and 95% confidence intervals (CIs) for DESS and DESS+PDFS compared with the conventional protocol were calculated and tested using exact McNemar tests. The percentage of observations where DESS or DESS+PDFS had equivalent confidence ratings to DESS+Conv were tested with exact symmetry tests. Interreader agreement was calculated using Krippendorff's alpha.RESULTS: DESS had a PPA of 90% (88-92% CI) and NPA of 99% (99-99% CI). DESS+PDFS had increased PPA of 99% (95-99% CI) and NPA of 100% (99-100% CI) compared with DESS (both P < 0.001). DESS had equivalent diagnostic confidence to DESS+Conv in 94% of findings, whereas DESS+PDFS had equivalent diagnostic confidence in 99% of findings (both P < 0.001). All readers had moderate concordance for all three protocols (Krippendorff's alpha 47-48%).DATA CONCLUSION: Both 1) 5-minute 3D-DESS with separated echoes and 2) 5-minute 3D-DESS paired with a 2-minute coronal PDFS sequence depicted knee abnormalities similarly to a routine clinical knee MRI protocol, which may be a promising technique for abbreviated knee MRI.LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018.

    View details for PubMedID 30582251

  • Super-resolution musculoskeletal MRI using deep learning MAGNETIC RESONANCE IN MEDICINE Chaudhari, A. S., Fang, Z., Kogan, F., Wood, J., Stevens, K. J., Gibbons, E. K., Lee, J., Gold, G. E., Hargreaves, B. A. 2018; 80 (5): 2139–54

    View details for DOI 10.1002/mrm.27178

    View details for Web of Science ID 000448872700033

  • Super-resolution musculoskeletal MRI using deep learning. Magnetic resonance in medicine Chaudhari, A. S., Fang, Z., Kogan, F., Wood, J., Stevens, K. J., Gibbons, E. K., Lee, J. H., Gold, G. E., Hargreaves, B. A. 2018


    PURPOSE: To develop a super-resolution technique using convolutional neural networks for generating thin-slice knee MR images from thicker input slices, and compare this method with alternative through-plane interpolation methods.METHODS: We implemented a 3D convolutional neural network entitled DeepResolve to learn residual-based transformations between high-resolution thin-slice images and lower-resolution thick-slice images at the same center locations. DeepResolve was trained using 124 double echo in steady-state (DESS) data sets with 0.7-mm slice thickness and tested on 17 patients. Ground-truth images were compared with DeepResolve, clinically used tricubic interpolation, and Fourier interpolation methods, along with state-of-the-art single-image sparse-coding super-resolution. Comparisons were performed using structural similarity, peak SNR, and RMS error image quality metrics for a multitude of thin-slice downsampling factors. Two musculoskeletal radiologists ranked the 3 data sets and reviewed the diagnostic quality of the DeepResolve, tricubic interpolation, and ground-truth images for sharpness, contrast, artifacts, SNR, and overall diagnostic quality. Mann-Whitney U tests evaluated differences among the quantitative image metrics, reader scores, and rankings. Cohen's Kappa (kappa) evaluated interreader reliability.RESULTS: DeepResolve had significantly better structural similarity, peak SNR, and RMS error than tricubic interpolation, Fourier interpolation, and sparse-coding super-resolution for all downsampling factors (p<.05, except 4*and 8*sparse-coding super-resolution downsampling factors). In the reader study, DeepResolve significantly outperformed (p<.01) tricubic interpolation in all image quality categories and overall image ranking. Both readers had substantial scoring agreement (kappa=0.73).CONCLUSION: DeepResolve was capable of resolving high-resolution thin-slice knee MRI from lower-resolution thicker slices, achieving superior quantitative and qualitative diagnostic performance to both conventionally used and state-of-the-art methods.

    View details for PubMedID 29582464

  • Accelerated three-dimensional multispectral MRI with robust principal component analysis for separation of on- and off-resonance signals MAGNETIC RESONANCE IN MEDICINE Levine, E., Stevens, K., Beaulieu, C., Hargreaves, B. 2018; 79 (3): 1495–1505


    To enable highly accelerated distortion-free MRI near metal by separating on- and off-resonance to exploit the redundancy of slice-phase encoding for the dominant on-resonance component.Multispectral MRI techniques resolve off-resonance distortions by a combination of limited excitation bins and additional encoding. Inspired by robust principal component analysis, a novel compact representation of multispectral images as a sum of rank-one and sparse matrices corresponding to on- and off-resonance respectively is described. This representation is used in a calibration-free and model-free reconstruction for data with an undersampling pattern that varies between bins. Retrospective undersampling was used to compare the proposed reconstruction and bin-by-bin compressed sensing. Hip images were acquired in eight patients with standard and prospectively undersampled three-dimensional multispectral imaging, and image quality was evaluated by two radiologists on a 5-point scale.Experiments with retrospective undersampling showed that the enhanced sparsity afforded by the separation greatly reduces reconstruction errors and artifacts. Images from prospectively undersampled multispectral imaging offered 2.6-3.4-fold (18-24-fold overall) acceleration compared to standard multispectral imaging with parallel imaging and partial-Fourier acceleration with equivalence in all qualitative assessments within a tolerance of one point (P < 0.004).Three-dimensional multispectral imaging can be highly accelerated by varying undersampling between bins and separating on- and off-resonance. Magn Reson Med 79:1495-1505, 2018. © 2017 International Society for Magnetic Resonance in Medicine.

    View details for PubMedID 28686800

    View details for PubMedCentralID PMC5756705

  • MRI of the Extremities CLINICAL EMERGENCY RADIOLOGY, 2ND EDITION Stevens, K. J., Mohan, S. V., Fox, J. 2017: 583–629
  • A Case of Meningococcal Pyomyositis in an Otherwise Healthy Adult. Open forum infectious diseases Barakat, M. T., Gajurel, K., Fischer, K., Stevens, K., Ozdalga, E., Montoya, J. G. 2016; 3 (3): ofw087-?


    The clinical spectrum of Neisseria meningitidis can range from nasopharyngeal colonization to life-threatening invasive diseases such as meningitis. However, its etiologic role in invasive pyomyositis (PM) has never been reported before in the English language. In this study, we report the first case of PM in the English language and the second case in the literature caused by N meningitidis.

    View details for PubMedID 27703989

  • Musculoskeletal imaging insight 2015: Kenya SKELETAL RADIOLOGY Stevens, K. J., Mutiso, K., Sconfienza, L. M., Monu, J. 2016; 45 (7): 883-888


    Over the past 6 years the International Skeletal Society (ISS) outreach programs have become popular amongst the various radiology organizations in sub-Saharan Africa. So much so that that the ISS outreach is now routinely expected to participate in many of the international radiology conferences in that part of the world. The organizational planning for an outreach visit to Kenya took place over a 3-year period. Eventually a double-headed event; the seventh and eighth sub-Saharan outreach efforts were organized in Nairobi and in Mombasa, Kenya. The Nairobi outreach was an educational course on musculoskeletal imaging at the University of Nairobi and the Aga Khan University in Nairobi from 26 to 28 May 2015. The Mombasa outreach was organized in collaboration with the African Society of Radiology (ASR) at their annual meeting in Mombasa from 30 May to 2 June 2015.

    View details for DOI 10.1007/s00256-016-2391-x

    View details for PubMedID 27115883

  • A Case of Meningococcal Pyomyositis in an Otherwise Healthy Adult OPEN FORUM INFECTIOUS DISEASES Barakat, M. T., Gajurel, K., Fischer, K., Stevens, K., Ozdalga, E., Montoya, J. G. 2016; 3 (3)
  • Elbow Imaging in Sport: Sports Imaging Series RADIOLOGY Bucknor, M. D., Stevens, K. J., Steinbach, L. S. 2016; 279 (1): 12-28


    Elbow pain is a frequent presenting symptom in athletes, particularly athletes who throw. The elbow can be injured as a result of acute trauma, such as a direct blow or a fall onto an outstretched hand or from chronic microtrauma. In particular, valgus extension overload during the throwing motion can precipitate a cascade of chronic injuries that can be debilitating for both casual and high-performance athletes. Prompt imaging evaluation facilitates accurate diagnosis and appropriate targeted interventions.

    View details for DOI 10.1148/radiol.2016150501

    View details for Web of Science ID 000378709700002

    View details for PubMedID 26989928

  • MRI findings of serous atrophy of bone marrow and associated complications EUROPEAN RADIOLOGY Boutin, R. D., White, L. M., Laor, T., Spitz, D. J., Lopez-Ben, R. R., Stevens, K. J., Bredella, M. A. 2015; 25 (9): 2771-2778


    To report the MRI appearance of serous atrophy of bone marrow (SABM) and analyse clinical findings and complications of SABM.A retrospective search of MRI examinations of SABM was performed. Symptoms, underlying conditions, MRI findings, delay in diagnosis and associated complications were recorded.We identified 30 patients (15 male, 15 female; mean age: 46 ± 21 years) with MRI findings of SABM. Underlying conditions included anorexia nervosa (n = 10), cachexia from malignant (n = 5) and non-malignant (n = 7) causes, massive weight loss after bariatric surgery (n = 1), biliary atresia (n = 1), AIDS (n = 3), endocrine disorders (n = 2) and scurvy (n = 1). MRI showed mildly hypointense signal on T1- weighted and hyperintense signal on fat-suppressed fluid-sensitive images of affected bone marrow in all cases and similar signal abnormalities of the adjacent subcutaneous fat in 29/30 cases. Seven patients underwent repeat MRI due to initial misinterpretation of bone marrow signal as technical error. Superimposed fractures of the hips and lower extremities were common (n = 14).SABM occurs most commonly in anorexia nervosa and cachexia. MRI findings of SABM are often misinterpreted as technical error requiring unnecessary repeat imaging. SABM is frequently associated with fractures of the lower extremities.• SABM occurs in several underlying conditions, most commonly anorexia nervosa and cachexia. • Abnormal marrow signal is often misinterpreted as technical error requiring unnecessary repeat imaging. • SABM is frequently associated with stress fractures. • Fractures in SABM can be obscured by marrow signal abnormality on MRI.

    View details for DOI 10.1007/s00330-015-3692-5

    View details for Web of Science ID 000359396700031

    View details for PubMedID 25773942

  • Approach to MR Imaging of the Elbow and Wrist: Technical Aspects and Innovation. Magnetic resonance imaging clinics of North America Johnson, D., Stevens, K. J., Riley, G., Shapiro, L., Yoshioka, H., Gold, G. E. 2015; 23 (3): 355-366


    Wrist and elbow MR imaging technology is advancing at a dramatic rate. Wrist and elbow MR imaging is performed at medium and higher field strengths with more specialized surface coils and more variable pulse sequences and postprocessing techniques. High field imaging and improved coils lead to an increased signal-to-noise ratio and increased variety of soft tissue contrast options. Three-dimensional imaging is improving in terms of usability and artifacts. Some of these advances have challenges in wrist and elbow imaging, such as postoperative patient imaging, cartilage mapping, and molecular imaging. This review considers technical advances in hardware and software and their clinical applications.

    View details for DOI 10.1016/j.mric.2015.04.008

    View details for PubMedID 26216768

    View details for PubMedCentralID PMC4518502

  • Approach to MR Imaging of the Elbow and Wrist: Technical Aspects and Innovation. Magnetic resonance imaging clinics of North America Johnson, D., Stevens, K. J., Riley, G., Shapiro, L., Yoshioka, H., Gold, G. E. 2015; 23 (3): 355-366


    Wrist and elbow MR imaging technology is advancing at a dramatic rate. Wrist and elbow MR imaging is performed at medium and higher field strengths with more specialized surface coils and more variable pulse sequences and postprocessing techniques. High field imaging and improved coils lead to an increased signal-to-noise ratio and increased variety of soft tissue contrast options. Three-dimensional imaging is improving in terms of usability and artifacts. Some of these advances have challenges in wrist and elbow imaging, such as postoperative patient imaging, cartilage mapping, and molecular imaging. This review considers technical advances in hardware and software and their clinical applications.

    View details for DOI 10.1016/j.mric.2015.04.008

    View details for PubMedID 26216768

  • Femoral Neck Stress Fractures and Imaging Features of Femoroacetabular Impingement PM&R Goldin, M., Anderson, C. N., Fredericson, M., Safran, M. R., Stevens, K. J. 2015; 7 (6): 584-592


    Prior literature has suggested an association between the radiographic signs of femoroacetabular impingement (FAI) and femoral neck stress fractures (FNSF) or femoral neck stress reactions (FNSR). At the time of the writing of this article, no study has described the association of FAI and FNSF/FNSR along with the need for surgical intervention and outcomes.To determine the prevalence of radiographic features of FAI in patients diagnosed with FNSF.Retrospective case series.Tertiary care, institutional setting.A medical records search program (Stanford Translational Research Integrated Database Environment, Stanford University, California) was used to retrospectively search for patients 18-40 years old with a history of FNSF or FNSR. The records were obtained from the period July 25, 2003, to September 23, 2011.For assessment of risk factors, plain radiographs and magnetic resonance imaging studies were reviewed for features of cam or pincer FAI. Medical records were reviewed to determine whether patients required operative intervention.Incidence of abnormal alpha (α) angle, abnormal anterior offset ratio, abnormal femoral head-neck junction, coxa profunda, positive crossover sign, and abnormal lateral center-to-edge angle.Twenty-one female and 3 male participants (mean age 27 years, range 19-39 years) were identified with magnetic resonance imaging evidence of femoral neck stress injury. Cam morphology was seen in 10 patients (42%). Pincer morphology could be assessed in 18 patients, with coxa profunda in 14 (78%) and acetabular retroversion in 6 (14%). Features of combined pincer and cam impingement were observed in 4 patients (17%). Seven patients (29%) had operative intervention, with 3 (12%) requiring internal fixation of their femoral neck fractures, and all had radiographic evidence of fracture union after surgery. Four patients (17%) had persistent symptoms after healing of their FNSF with conservative treatment and eventually required surgery for FAI, 3 had no pain at final follow-up 1 year post-surgery, and one patient was lost to follow-up.The results of the current study suggest that patients in the general population with femoral neck stress injuries have a higher incidence of bony abnormalities associated with pincer impingement, including coxa profunda and acetabular retroversion, although it is unclear whether pincer FAI is a true risk factor in the development of FNSF.

    View details for DOI 10.1016/j.pmrj.2014.12.008

    View details for Web of Science ID 000356053400005

    View details for PubMedID 25591871

  • MRI of the Hip for the evaluation of femoroacetabular impingement; past, present, and future. Journal of magnetic resonance imaging : JMRI Riley, G. M., McWalter, E. J., Stevens, K. J., Safran, M. R., Lattanzi, R., Gold, G. E. 2015; 41 (3): 558-572


    The concept of femoroacetabular impingement (FAI) has, in a relatively short time, come to the forefront of orthopedic imaging. In just a few short years MRI findings that were in the past ascribed to degenerative change, normal variation, or other pathologies must now be described and included in radiology reports, as they have been shown, or are suspected to be related to, FAI. Crucial questions have come up in this time, including: what is the relationship of bony morphology to subsequent cartilage and labral damage, and most importantly, how is this morphology related to the development of osteoarthritis? In this review, we attempt to place a historical perspective on the controversy, provide guidelines for interpretation of MRI examinations of patients with suspected FAI, and offer a glimpse into the future of MRI of this complex condition. J. Magn. Reson. Imaging 2014. © 2014 Wiley Periodicals, Inc.

    View details for DOI 10.1002/jmri.24725

    View details for PubMedID 25155435

  • MR Imaging Near Metallic Implants Using MAVRIC SL: Initial Clinical Experience at 3T ACADEMIC RADIOLOGY Gutierrez, L. B., Do, B. H., Gold, G. E., Hargreaves, B. A., Koch, K. M., Worters, P. W., Stevens, K. J. 2015; 22 (3): 370-379


    To compare the effectiveness of multiacquisition with variable resonance image combination selective (MAVRIC SL) with conventional two-dimensional fast spin-echo (2D-FSE) magnetic resonance (MR) techniques at 3T in imaging patients with a variety of metallic implants.Twenty-one 3T MR studies were obtained in 19 patients with different types of metal implants. Paired MAVRIC SL and 2D-FSE sequences were reviewed by two radiologists and compared for in-plane and through-plane metal artifact, visualization of the bone implant interface and surrounding soft tissues, blurring, and overall image quality using a two-tailed Wilcoxon signed rank test. The area of artifact on paired images was measured and compared using a paired Wilcoxon signed rank test. Changes in patient management resulting from MAVRIC SL imaging were documented.Significantly less in-plane and through-plane artifact was seen with MAVRIC SL, with improved visualization of the bone-implant interface and surrounding soft tissues, and superior overall image quality (P = .0001). Increased blurring was seen with MAVRIC SL (P = .0016). MAVRIC SL significantly decreased the image artifact compared to 2D-FSE (P = .0001). Inclusion of MAVRIC SL to the imaging protocol determined the need for surgery or type of surgery in five patients and ruled out the need for surgery in 13 patients. In three patients, the area of interest was well seen on both MAVRIC SL and 2D-FSE images, so the addition of MAVRIC had no effect on patient management.Imaging around metal implants with MAVRIC SL at 3T significantly improved image quality and decreased image artifact compared to conventional 2D-FSE imaging techniques and directly impacted patient management.

    View details for DOI 10.1016/j.acra.2014.09.010

    View details for PubMedID 25435186

  • Validation of a Novel Radiographic Scoring System for Calcinosis Affecting the Hands of Patients With Systemic Sclerosis ARTHRITIS CARE & RESEARCH Chung, L., Valenzuela, A., Fiorentino, D., Stevens, K., Li, S., Harris, J., Hutchinson, C., Assassi, S., Beretta, L., Lakshminarayanan, S., Rodriguez-Reyna, T. S., Denton, C. P., Taillefer, R. G., Herrick, A. L., Baron, M. 2015; 67 (3): 425-430


    Objective: There are currently no validated outcome measures to assess calcinosis severity in systemic sclerosis (SSc). We sought to develop and validate a novel radiographic scoring system for calcinosis affecting the hands of SSc patients for potential use in future clinical trials. Methods: Following a 1-hour teleconference training session, 12 investigators (8 rheumatologists, 1 dermatologist, 3 radiologists) scored 12 hand radiographs in random order using two scoring systems (termed "simple" and "complex"), and re-scored 2 randomly assigned radiographs after a minimum of 24 hours. Inter-rater and intra-rater reliability were assessed using a weighted kappa coefficient for the simple system, and intraclass correlation coefficient (ICC) for the complex system (ICC < 0.4 poor, 0.4-0.7 moderate, > 0.7 excellent). Results: Mean time to complete the complex scoring system was significantly longer than the simple scoring system (4.0 vs. 0.4 minutes, p<.0001). Overall inter-rater reliability for the simple scoring system was poor (kappa=0.39, 95% CI 0.1-0.52), but improved if dichotomized as mild/moderate vs. severe (kappa=0.51, 95% CI 0.26-0.7). Inter-rater reliability was excellent for the complex scoring system (ICC=0.89, 95% CI 0.86-0.92). Intra-rater reliability was moderate for the simple scoring system (kappa=0.67, 95% CI 0.37-0.96), but almost perfect for the complex scoring system (ICC=0.93, 95%CI 0.89-0.97). Conclusion: We developed a novel radiographic scoring system that accounts for the area coverage, density, and anatomic location of calcinosis affecting the hands in patients with SSc. This scoring system is feasible with excellent reliability and should undergo further validation testing for use in clinical trials. © 2014 American College of Rheumatology.

    View details for DOI 10.1002/acr.22434

    View details for PubMedID 25155948

  • MRI of the Hip for the Evaluation of Femoroacetabular Impingement; Past, Present, and Future JOURNAL OF MAGNETIC RESONANCE IMAGING Riley, G. M., McWalter, E. J., Stevens, K. J., Safran, M. R., Lattanzi, R., Gold, G. E. 2015; 41 (3): 558–72

    View details for DOI 10.1002/jmri.24725

    View details for Web of Science ID 000450816400001

  • Metal Artifact Reduction With MAVRIC SL at 3-T MRI in Patients With Hip Arthroplasty AMERICAN JOURNAL OF ROENTGENOLOGY Choi, S., Koch, K. M., Hargreaves, B. A., Stevens, K. J., Gold, G. E. 2015; 204 (1): 140-147


    The objective of our study was to compare the multiacquisition variable-resonance image combination selective (MAVRIC SL) sequence with the 2D fast spin-echo (FSE) sequence for metal artifact reduction on 3-T MRI in patients with hip arthroplasty (HA).Matched 2D FSE and MAVRIC SL images of 21 hips (19 patients with HA) were included in the study group. Paired image sets, composed of 13 coronal and 12 axial slices (total, 25 image sets), of the 21 hips were evaluated. For quantitative analysis, the artifact area was measured at the level of the hip and femur. For qualitative analysis, two musculoskeletal radiologists independently compared paired 2D FSE and MAVRIC SL sets in terms of artifacts, depiction of anatomic detail, level of diagnostic confidence, and detection of abnormal findings.The measured artifact area was significantly smaller (p < 0.05) on MAVRIC SL than 2D FSE at both the level of hip (59.9% reduction with MAVRIC SL) and femur (31.3% reduction with MAVRIC SL). The artifact score was also significantly decreased (p < 0.0001) with MAVRIC SL compared with 2D FSE for both reviewers. The hip joint capsule and the muscle and tendon attachment sites of the obturator externus and iliopsoas muscles were better depicted with MAVRIC SL than 2D FSE (p < 0.0125). Abnormal findings were significantly better shown on MAVRIC SL imaging compared with 2D FSE imaging (p < 0.0001).The MAVRIC SL sequence can significantly reduce metal artifact on 3-T MRI compared with the 2D FSE sequence and can increase diagnostic confidence of 3-T MRI in patients with total HA.

    View details for DOI 10.2214/AJR.13.11785

    View details for Web of Science ID 000348562300044

    View details for PubMedID 25539249

    View details for PubMedCentralID PMC4321802

  • Ultrasound-guided musculoskeletal interventions in American football: 18 years of experience. AJR. American journal of roentgenology Dave, R. B., Stevens, K. J., Shivaram, G. M., McAdams, T. R., Dillingham, M. F., Beaulieu, C. F. 2014; 203 (6): W674-83


    Myotendinous strains, contusions, and hematomas are common injuries in American football. Along with ligament sprains and inflammatory disorders, musculoskeletal injuries often result in lost participation time. This article summarizes 18 years of experience with 128 ultrasound-guided drainages and injections in 69 football players with 88 injuries.When performed by an operator with sufficient expertise in diagnostic and procedural skills, ultrasound-guided musculoskeletal interventions are minimally invasive, are safe, and can play an integral role in injury management.

    View details for DOI 10.2214/AJR.14.12678

    View details for PubMedID 25415734

  • Late-onset en coup de sabre of the skull. Skeletal radiology Mohan, S. V., Nittur, V., Stevens, K. J. 2013; 42 (10): 1447-1450


    En coup de sabre is a rare subtype of linear scleroderma that characteristically affects the skin, underlying muscle, and bone of the frontoparietal region of the face and scalp. It typically presents in the first two decades of life, and may be associated with focal neurological deficits. We present a case of late-onset en coup de sabre of the frontal bone where the diagnosis was further complicated by a history of breast cancer, prior trauma to the region, and use of topical medication.

    View details for DOI 10.1007/s00256-013-1617-4

    View details for PubMedID 23615776

  • Validation Of a Novel Radiographic Scoring System For Calcinosis Affecting The Hands Of Patients With Systemic Sclerosis. Chung, L., Vergara, A., Fiorentino, D., Stevens, K., Li, S., Harris, J., Hutchinson, C. E., Assassi, S., Beretta, L., Lakshminarayanan, S., Reyna, T., Denton, C. P., Taillefer, R. G., Tatibouet, S., Herrick, A., Baron, M. WILEY-BLACKWELL. 2013: S289–S290
  • Preface. Radiologic clinics of North America Stevens, K. J. 2013; 51 (3): xi-xii

    View details for DOI 10.1016/j.rcl.2013.03.001

    View details for PubMedID 23622098

  • Femoroacetabular Impingement RADIOLOGIC CLINICS OF NORTH AMERICA Dimmick, S., Stevens, K. J., Brazier, D., Anderson, S. E. 2013; 51 (3): 337-?


    Femoroacetabular impingement (FAI) of the hip is a well-recognized entity that can cause hip pain and limit range of motion. Although there are 2 types of FAI (cam and pincer), these 2 entities most commonly coexist. Plain radiographs and magnetic resonance imaging are commonly used to assess FAI, and play an integral role in diagnosis in conjunction with patient symptoms and clinical examination. Treatment of FAI is also evolving, with arthroscopic management becoming increasingly more popular. This review provides an overview of the proposed etiology, mechanisms, clinical history, imaging, and treatment of FAI.

    View details for DOI 10.1016/j.rcl.2012.12.002

    View details for Web of Science ID 000319085300002

    View details for PubMedID 23622088

  • Imaging of Cysts and Bursae About the Knee RADIOLOGIC CLINICS OF NORTH AMERICA Steinbach, L. S., Stevens, K. J. 2013; 51 (3): 433-?


    Cystic lesions are common around the knee and are often encountered as an incidental finding on routine magnetic resonance imaging examinations. The clinical presentation of cysts and other fluid collections is variable, depending on their size, location, and relationship to adjacent anatomic structures. This article reviews the anatomy, etiology, clinical presentation, and imaging features of commonly occurring cystic lesions around the knee and discusses some of the potential pitfalls that may be encountered in clinical practice.

    View details for DOI 10.1016/j.rcl.2012.10.005

    View details for Web of Science ID 000319085300007

    View details for PubMedID 23622093

  • Compressed-Sensing multispectral imaging of the postoperative spine JOURNAL OF MAGNETIC RESONANCE IMAGING Worters, P. W., Sung, K., Stevens, K. J., Koch, K. M., Hargreaves, B. A. 2013; 37 (1): 243-248


    To apply compressed sensing (CS) to in vivo multispectral imaging (MSI), which uses additional encoding to avoid magnetic resonance imaging (MRI) artifacts near metal, and demonstrate the feasibility of CS-MSI in postoperative spinal imaging.Thirteen subjects referred for spinal MRI were examined using T2-weighted MSI. A CS undersampling factor was first determined using a structural similarity index as a metric for image quality. Next, these fully sampled datasets were retrospectively undersampled using a variable-density random sampling scheme and reconstructed using an iterative soft-thresholding method. The fully and undersampled images were compared using a 5-point scale. Prospectively undersampled CS-MSI data were also acquired from two subjects to ensure that the prospective random sampling did not affect the image quality.A two-fold outer reduction factor was deemed feasible for the spinal datasets. CS-MSI images were shown to be equivalent or better than the original MSI images in all categories: nerve visualization: P = 0.00018; image artifact: P = 0.00031; image quality: P = 0.0030. No alteration of image quality and T2 contrast was observed from prospectively undersampled CS-MSI.This study shows that the inherently sparse nature of MSI data allows modest undersampling followed by CS reconstruction with no loss of diagnostic quality.

    View details for DOI 10.1002/jmri.23750

    View details for PubMedID 22791572

  • The Biceps Muscle from Shoulder to Elbow SEMINARS IN MUSCULOSKELETAL RADIOLOGY Stevens, K., Kwak, A., Poplawski, S. 2012; 16 (4): 296-315


    The biceps brachii plays an integral role in movement of the shoulder and elbow, and pathology can occur in athletes of all ages. Injuries of the proximal biceps tendon can be seen in overhead athletes as a result of chronic impingement, tendon instability, or tensile overload, often with accompanying lesions of the labrum or rotator cuff. Presentation may be insidious or can be precipitated by an acute event. Injuries to the distal biceps are more common in athletes involved in strength training such as weightlifters, or occasionally in contact sports. Although injury to the proximal and distal biceps can often be diagnosed clinically, MRI is an excellent imaging modality to evaluate the extent of disease and involvement of adjacent structures. This article reviews the anatomy of the biceps brachii from the shoulder to elbow and discusses commonly occurring pathology of the biceps and adjacent anatomical structures.

    View details for DOI 10.1055/s-0032-1327004

    View details for PubMedID 23047278

  • Fluoroscopically Guided Supraglenoid Tubercle Steroid Injections for the Management of Biceps Tendonitis PAIN PRACTICE Mitra, R., Nguyen, A., Stevens, K. J. 2011; 11 (4): 392-396


    The management of bicipital tendonitis can be challenging to the clinician. Traditionally, blind injections near the bicipital groove have been performed by clinicians with risk of bicipital tendon rupture or atrophy. Because of the inaccuracy and risk associated with blind bicipital tendon steroid injections, we sought to ascertain whether a fluoroscopically guided steroid injection into the region of the origin of the long head of the bicipital tendon (supraglenoid tubercle) was efficacious.A retrospective chart review of 6 consecutive patients with a diagnosis of bicipital tendonitis was performed. All patients underwent a fluoroscopically guided steroid/anesthetic injection into the supraglenoid tubercle of the shoulder. The main outcome measure was post-procedure change in visual analog pain scale; the secondary outcome was the physical examination (presence of a Speed's test).Ten cases were identified, but only 6 had complete data and were included in the analysis. Five of the 6 patients experienced a reduction in pain by 50% at follow-up.A fluoroscopically guided block injected into the supraglenoid tubercle may be effective in the management of bicipital tendonitis.

    View details for DOI 10.1111/j.1533-2500.2010.00424.x

    View details for PubMedID 21114615

  • Imaging of the Wrist at 1.5 Tesla Using Isotropic Three-Dimensional Fast Spin Echo Cube JOURNAL OF MAGNETIC RESONANCE IMAGING Stevens, K. J., Wallace, C. G., Chen, W., Rosenberg, J. K., Gold, G. E. 2011; 33 (4): 908-915


    To compare three-dimensional fast spin echo Cube (3D-FSE-Cube) with conventional 2D-FSE in MR imaging of the wrist.The wrists of 10 volunteers were imaged in a 1.5 Tesla MRI scanner using an eight-channel wrist coil. The 3D-FSE-Cube images were acquired in the coronal plane with 0.5-mm isotropic resolution. The 2D-FSE images were acquired in both coronal and axial planes for comparison. An ROI was placed in fluid, cartilage, and muscle for SNR analysis. Comparable coronal and axial images were selected for each sequence, and paired images were randomized and graded for blurring, artifact, anatomic details, and overall image quality by three blinded musculoskeletal radiologists.SNR of fluid, cartilage and muscle at prescribed locations were higher using 3D-FSE-Cube, without reaching statistical significance. Fluid-cartilage CNR was also higher with 3D-FSE-Cube, but not statistically significant. Blurring, artifact, anatomic details, and overall image quality were significantly better on coronal 3D-FSE-Cube images (P < 0.001), but significantly better on axial 2D-FSE images compared with axial 3D-FSE-Cube reformats (P < 0.01).Isotropic data from 3D-FSE-Cube allows reformations in arbitrary scan planes, which may make multiple 2D acquisitions unnecessary, and improve depiction of complex wrist anatomy. However, axial reformations suffer from blurring, likely due to T2 decay during the long echo train, limiting overall image quality in this plane.

    View details for DOI 10.1002/jmri.22494

    View details for PubMedID 21448957

  • Athletic Osteitis Pubis SPORTS MEDICINE Hiti, C. J., Stevens, K. J., Jamati, M. K., Garza, D., Matheson, G. O. 2011; 41 (5): 361-376


    Athletic osteitis pubis is a painful and chronic condition affecting the pubic symphysis and/or parasymphyseal bone that develops after athletic activity. Athletes with osteitis pubis commonly present with anterior and medial groin pain and, in some cases, may have pain centred directly over the pubic symphysis. Pain may also be felt in the adductor region, lower abdominal muscles, perineal region, inguinal region or scrotum. The pain is usually aggravated by running, cutting, hip adduction and flexion against resistance, and loading of the rectus abdominis. The pain can progress such that athletes are unable to sustain athletic activity at high levels. It is postulated that osteitis pubis is an overuse injury caused by biomechanical overloading of the pubic symphysis and adjacent parasymphyseal bone with subsequent bony stress reaction. The differential diagnosis for osteitis pubis is extensive and includes many other syndromes resulting in groin pain. Imaging, particularly in the form of MRI, may be helpful in making the diagnosis. Treatment is variable, but typically begins with conservative measures and may include injections and/or surgical procedures. Prolotherapy injections of dextrose, anti-inflammatory corticosteroids and a variety of surgical procedures have been reported in the literature with varying efficacies. Future studies of athletic osteitis pubis should attempt to define specific and reliable criteria to make the diagnosis of athletic osteitis pubis, empirically define standards of care and reduce the variability of proposed treatment regimens.

    View details for PubMedID 21510714

  • High Hamstring Tendinopathy: MRI and Ultrasound Imaging and Therapeutic Efficacy of Percutaneous Corticosteroid Injection AMERICAN JOURNAL OF ROENTGENOLOGY Zissen, M. H., Wallace, G., Stevens, K. J., Fredericson, M., Beaulieu, C. F. 2010; 195 (4): 993-998


    The goals of this study were to review the MRI and sonographic findings in patients diagnosed clinically with high hamstring tendinopathy and to evaluate the efficacy of ultrasound-guided corticosteroid injections in providing symptomatic relief.MRI is more sensitive than ultrasound in detecting peritendinous edema and tendinopathy at the proximal hamstring origin. Fifty percent of patients had symptomatic improvement lasting longer than 1 month after percutaneous corticosteroid injection, and 24% of patients had symptom relief for more than 6 months.

    View details for DOI 10.2214/AJR.09.3674

    View details for PubMedID 20858830

  • Magnetic Resonance Imaging of the Elbow in Athletes CLINICS IN SPORTS MEDICINE Stevens, K. J., McNally, E. G. 2010; 29 (4): 521-?


    Acute and chronic elbow pain is common, particularly in athletes. Although plain radiographs, ultrasound, and computed tomography all have a role to play in the investigation of elbow pain, magnetic resonance imaging (MRI) has emerged as the imaging modality of choice for diagnosis of soft tissue disease and osteochondral injury around the elbow. The high spatial resolution, excellent soft-tissue contrast, and multiplanar imaging capabilities of MRI make it ideal for evaluating the complex joint anatomy of the elbow. This article reviews imaging of common disease conditions occurring around the elbow in athletes, with an emphasis on MRI.

    View details for DOI 10.1016/j.csm.2010.06.004

    View details for PubMedID 20883896

  • Magnetic Resonance Imaging of the Elbow JOURNAL OF MAGNETIC RESONANCE IMAGING Stevens, K. J. 2010; 31 (5): 1036-1053


    Elbow pain is frequently encountered in clinical practice and can result in significant morbidity, particularly in athletes. Magnetic resonance imaging (MRI) is an excellent diagnostic imaging tool for the evaluation of soft tissue and osteochondral pathology around the elbow. Recent advances in magnetic field strength and coil design have lead to improved spatial resolution and superior soft tissue contrast, making it ideal for visualization of complex joint anatomy. This article describes the normal imaging appearances of anatomy around the elbow and reviews commonly occurring ligamentous, myotendinous, neural, and bursal pathology around the elbow.

    View details for DOI 10.1002/jmri.22154

    View details for PubMedID 20432337

  • Imaging and Ultrasound-Guided Steroid Injection of Internal Oblique Muscle Strains in Baseball Pitchers AMERICAN JOURNAL OF SPORTS MEDICINE Stevens, K. J., Crain, J. M., Akizuki, K. H., Beaulieu, C. F. 2010; 38 (3): 581-585


    Internal oblique muscle injuries are common in professional baseball pitchers and may require a prolonged convalescence of up to 10 weeks. Most strains can be diagnosed clinically, but imaging can be helpful to assess the severity of injury, which may predict recovery and return to play.Ultrasound-guided injection of steroid and local anesthetic into the muscle tear can speed recovery and subsequent return to play.Case series; Level of evidence, 4.Three professional baseball pitchers with acute tears of the internal oblique muscle confirmed by magnetic resonance imaging underwent ultrasound-guided injection of steroid and local anesthetic.All 3 patients experienced significant pain relief within a few days of the injection and were able to pitch at full speed within 3 weeks of injury (mean, 21 days) and return to able status by 5 weeks (mean, 30.7 days). The 3 athletes continue to pitch in Major League Baseball 36 months, 36 months, and 14 months, respectively, after injury, and none have sustained reinjury during this time.Therapeutic injection of steroids and anesthetic under ultrasound guidance appears to speed recovery and rehabilitation in professional baseball pitchers with acute side strains.

    View details for DOI 10.1177/0363546509350105

    View details for PubMedID 20051499

  • Dynamic Ultrasound to Diagnose Subluxating Biceps Femoris Tendon over the Fibular Head: A Case Report PM&R Huang, L., Stevens, K. J., Fredericson, M. 2009; 1 (7): 681-683
  • Ankle: Isotropic MR Imaging with 3D-FSE-Cube-Initial Experience in Healthy Volunteers RADIOLOGY Stevens, K. J., Busse, R. F., Han, E., Brau, A. C., Beatty, P. J., Beaulieu, C. F., Gold, G. E. 2008; 249 (3): 1026-1033


    The purpose of this prospective study was to compare a new isotropic three-dimensional (3D) fast spin-echo (FSE) pulse sequence with parallel imaging and extended echo train acquisition (3D-FSE-Cube) with a conventional two-dimensional (2D) FSE sequence for magnetic resonance (MR) imaging of the ankle. After institutional review board approval and informed consent were obtained and in accordance with HIPAA privacy guidelines, MR imaging was performed in the ankles of 10 healthy volunteers (four men, six women; age range, 25-41 years). Imaging with the 3D-FSE-Cube sequence was performed at 3.0 T by using both one-dimensional- and 2D-accelerated autocalibrated parallel imaging to decrease imaging time. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) with 3D-FSE-Cube were compared with those of the standard 2D FSE sequence. Cartilage, muscle, and fluid SNRs were significantly higher with the 3D-FSE-Cube sequence (P < .01 for all). Fluid-cartilage CNR was similar for both techniques. The two sequences were also compared for overall image quality, blurring, and artifacts. No significant difference for overall image quality and artifacts was demonstrated between the 2D FSE and 3D-FSE-Cube sequences, although the section thickness in 3D-FSE-Cube imaging was much thinner (0.6 mm). However, blurring was significantly greater on the 3D-FSE-Cube images (P < .04). The 3D-FSE-Cube sequence with isotropic resolution is a promising new MR imaging sequence for viewing complex joint anatomy.

    View details for DOI 10.1148/radiol.2493080227

    View details for PubMedID 19011194

  • Discordance rates between preliminary and final radiology reports on cross-sectional imaging studies at a level 1 trauma center ACADEMIC RADIOLOGY Stevens, K. J., Griffiths, K. L., Rosenberg, J., Mahadevan, S., Zatz, L. M., Leung, A. N. 2008; 15 (10): 1217-1226


    The goal was to determine discordance rates between preliminary radiology reports provided by on-call radiology house staff and final reports from attending radiologists on cross-sectional imaging studies requested by emergency department staff after hours.A triplicate carbon copy reporting form was developed to provide permanent records of preliminary radiology reports and to facilitate communication of discrepant results to the emergency department. Data were collected over 21 weeks to determine the number of discordant readings. Patients' medical records were reviewed to show whether discrepancies were significant or insignificant and to assess their impact on subsequent management and patient outcome.The emergency department requested 2830 cross-sectional imaging studies after hours and 2311 (82%) had a copy of the triplicate form stored in radiology archives. Discrepancies between the preliminary and final report were recorded in 47 (2.0%), with 37 (1.6%) considered significant: 14 patients needed no change, 13 needed a minor change, and 10 needed a major change in subsequent management. Ten (0.43%) of the discordant scans were considered insignificant. A random sample of 104 (20%) of the 519 scans without a paper triplicate form was examined. Seventy-one (68%) did have a scanned copy of the triplicate form in the electronic record, with a discrepancy recorded in 3 (4.2%), which was not statistically different from the main cohort (P = .18).Our study suggests a high level of concordance between preliminary reports from on-call radiology house staff and final reports by attending subspecialty radiologists on cross-sectional imaging studies requested by the emergency department.

    View details for DOI 10.1016/j.acra.2008.03.017

    View details for PubMedID 18790392

  • Tibial aperture bone disruption after retrograde versus antegrade tibial tunnel drilling: a cadaveric study KNEE SURGERY SPORTS TRAUMATOLOGY ARTHROSCOPY McAdams, T. R., Biswal, S., Stevens, K. J., Beaulieu, C. F., Mandelbaum, B. R. 2008; 16 (9): 818-822


    The purpose of this study is to compare the local microfracture effects of antegrade versus retrograde drilling of the tibial tunnel in ACL reconstruction. Arthroscopic ACL excision was performed on eight matched cadaveric knees. Arthroscopic guided tibial tunnel reaming was performed in either an antegrade (four) or retrograde (four) direction. A 3 x 3 cm section of proximal tibial surrounding the tibial aperture was removed with open dissection, and each section underwent micro-computed tomography analysis. Three musculoskeletal radiologists graded the specimens for bone aperture disruption and discrete fracture lines. Tibial aperture irregularity was seen in all four of the antegrade specimens (mean, Grade 1.5), and in none of the retrograde specimens. Discrete fracture lines were present in all four antegrade specimens (mean 10.13 mm depth; 8.95 mm length). No fracture lines were seen in the retrograde group. Retrograde drilling of the tibial tunnel in ACL reconstruction results in less microfracture trauma to the surrounding aperture bone. The use of retrograde drilling in ACL reconstruction may decrease synovialization of the graft-tissue interface when compared to antegrade drilling.

    View details for DOI 10.1007/s00167-008-0554-6

    View details for PubMedID 18516594

  • Reduction of truncation artifacts in rapid 3D articular cartilage imaging JOURNAL OF MAGNETIC RESONANCE IMAGING Rakow-Penner, R., Gold, G., Daniel, B., Stevens, K., Rosenberg, J., Mazin, S. 2008; 27 (4): 860-865


    To reduce Gibbs ringing artifact in three-dimensional (3D) articular knee cartilage imaging with linear prediction (LP).A reconstruction method using LP in 3D was applied to truncated data sets of six healthy knees. The technique first linearizes the data before applying the prediction algorithm. Three radiologists blindly reviewed and ranked images of the full, truncated, and predicted data sets. Statistical analysis of the radiologists' reviews was performed for image quality, clinical acceptability of the images, and equivalence with the gold standard.LP applied to 3D knee cartilage imaging allows for 40% decreased scan time while providing image quality with statistical equivalence to a full data set.3D spoiled gradient echo imaging (SPGR) knee cartilage imaging requires significant scan time. This 40% reduction in scan time will allow such scans to be more feasible without sacrificing clinical acceptability.

    View details for DOI 10.1002/jmri.21312

    View details for PubMedID 18383247

  • VEGF and osteosclerosis in POEMS syndrome ANNALS OF HEMATOLOGY Guetgemann, I., Stevens, K., Loftus, D., Schmidt-Wolf, I. G., George, T. I. 2008; 87 (3): 243-245

    View details for DOI 10.1007/s00277-007-0425-0

    View details for Web of Science ID 000252538900012

    View details for PubMedID 18172647

  • Introduction to diagnostic musculoskeletal ultrasound - Part 2: Examination of the lower limb AMERICAN JOURNAL OF PHYSICAL MEDICINE & REHABILITATION Chew, K., Stevens, K. J., Wang, T., Fredericson, M., Lew, H. L. 2008; 87 (3): 238-248


    This is the second of two articles focusing on ultrasound examination of musculoskeletal components of the upper and lower limbs. Treatment of musculoskeletal injuries is based on establishing an accurate diagnosis. No one would dispute that a good history and physical examination by a competent clinician can help achieve that in the majority of cases. However, musculoskeletal imaging is also an essential adjunct in the work-up of many musculoskeletal disorders. This article describes the ultrasound examination of the lower limb in terms of anatomic structure. Normal and pathologic ultrasound features of these structures, including muscles, tendons, ligaments, bursae, and other soft tissues of the lower limb, will be described by reviewing several representative pathologies commonly seen in musculoskeletal medicine.

    View details for DOI 10.1097/PHM.0b013e31816198c2

    View details for Web of Science ID 000253342200012

    View details for PubMedID 18174843

  • VEGF and osteosclerosis in POEMS syndrome Annal of Hematology Gutgemann I, Stevens K, Loftus D, Schmidt-Wolf IGH, George TI 2008; 87: 87
  • MRI of the Extremities CLINICAL EMERGENCY RADIOLOGY Stevens, K. J., Fox, J. C. 2008: 586–632
  • Temporal progression of skeletal cystic angiomatosis SKELETAL RADIOLOGY Shivaram, G. M., Pai, R. K., Ireland, K. B., Stevens, K. J. 2007; 36 (12): 1199-1204


    Cystic angiomatosis is a rare, benign, multifocal disorder of bone and viscera, in which angiomatous deposits of both vascular and lymphatic elements result in bone lysis and organ dysfunction. We report on a case of late-onset cystic angiomatosis in a Caucasian woman who first presented at age 35 years with a lytic expansile lesion of the proximal humerus, initially diagnosed as low-grade hemangio-endothelioma. This was treated with injection of cement and prophylactic pinning. However, the lesion continued to grow, and, 5 years later, she was discovered to have disseminated bony involvement, initially thought to represent metastatic disease. However, further investigation revealed a diagnosis of cystic angiomatosis, and the patient was treated with bisphosphonates. Follow-up over a 15-year period since her initial presentation at age 35 years has shown osteosclerotic conversion of many of the lesions, with development of numerous pathologic stress fractures that have failed to heal, despite operative intervention.

    View details for DOI 10.1007/s00256-007-0378-3

    View details for PubMedID 17912518

  • Utility of Judet views in pre-operative assessment of acetabular osteolysis American Journal of Orthopedics Thomas AJ, Stevens K, Goodman SB 2007; 36 (7): 107 - 108
  • Anterior cruciate ligament tears and associated injuries. Topics in magnetic resonance imaging Stevens, K. J., Dragoo, J. L. 2006; 17 (5): 347-362


    Anterior cruciate ligament (ACL) tears are a commonly sustained sports injury, often occurring in association with meniscal tears and trauma to other ligamentous structures around the knee. Diagnosis can often be made clinically, but assessment may be difficult in the acute setting when there is a large joint effusion and severe pain. Plain radiographs may detect the presence of a joint effusion and any associated fractures. However, magnetic resonance imaging is vital for assessing acute knee injuries and plays an important role in deciding treatment options and planning surgical intervention. Some of the associated meniscal and ligamentous injuries can be subtle and may easily be overlooked if these structures are not scrutinized closely. This article will discuss the anatomy of the ACL and the mechanisms and initial clinical assessment of ACL injuries, and review the imaging features of ACL tears and some of the associated injuries, including the posterolateral corner structures. These associated injuries have important implications for determining treatment options and subsequent return to athletic activities.

    View details for PubMedID 17414996

  • Advanced magnetic resonance imaging of articular cartilage ORTHOPEDIC CLINICS OF NORTH AMERICA Gold, G. E., Hargreaves, B. A., Stevens, K. J., Beaulieu, C. F. 2006; 37 (3): 331-?


    MRI is one of the most accurate imaging methods available to diagnose disorders of articular cartilage. Conventional two-dimensional and three-dimensional approaches show changes in cartilage morphology. Newer and substantially faster three-dimensional imaging methods show great promise to improve MRI of cartilage. These methods may allow acquisition of fluid-sensitive isotropic data that can be reformatted into arbitrary planes for improved detection and visualization of pathology. Unique MRI contrast mechanisms also allow clinicians to probe cartilage physiology and detect early changes in cartilage macromolecules.

    View details for DOI 10.1016/j.ocl.2006.04.006

    View details for PubMedID 16846765

  • Comparison of minimally invasive and conventional open posterolateral lumbar fusion using magnetic resonance imaging and retraction pressure studies JOURNAL OF SPINAL DISORDERS & TECHNIQUES Stevens, K. J., Spenciner, D. B., Griffiths, K. L., Kim, K. D., Zivienenberg-Lee, M., Alamin, T., Bammer, R. 2006; 19 (2): 77-86


    To determine whether minimally invasive lumbar spinal fusion results in less paraspinal muscle damage than conventional open posterior fusion.The maximum intramuscular pressure (IMP) generated by a minimally invasive and standard open retractor was compared in cadavers using an ultra-miniature pressure transducer. In a second clinical study, eight patients with either minimally invasive or open posterolateral lumbar spinal fusion underwent magnetic resonance imaging (MRI) scanning approximately 6 months post surgery. MRI was used to estimate edema and atrophy within multifidus, with T2 mapping and diffusion-weighted imaging allowing quantification of differences between the two surgical techniques.IMP measured with the minimally invasive retractor was 1.4 versus 4.7 kPa with the open retractor (P < 0.001). The minimally invasive retractor produced a transient maximal IMP only on initial expansion. Maximum IMP was constant throughout open retractor deployment. Striking visual differences in muscle edema were seen between open and minimally invasive groups on MRI. The mean T2 relaxation time at the level of fusion was 47 milliseconds in the minimally invasive and 90 milliseconds in the open group (P = 0.013). The mean apparent diffusion coefficient was 1357 x 10(-6) mm/s and 1626 x 10(-6) mm(2)/s (P = 0.0184), respectively.The peak IMP generated by the minimally invasive retractor was significantly less than with the open retractor. Postoperatively, less muscle edema was demonstrated after the minimally invasive lumbar spinal fusion, with lower mean T2 and apparent diffusion coefficient measurements supporting the hypothesis that less damage occurs using a minimally invasive approach.

    View details for PubMedID 16760779

  • Sunburst periosteal reaction in osteogenic sarcoma PEDIATRIC RADIOLOGY Gross, M., Stevens, K. 2005; 35 (6): 647-648

    View details for DOI 10.1007/s00247-005-1442-6

    View details for PubMedID 15812635

  • Driven equilibrium magnetic resonance imaging of articular cartilage: Initial clinical experience JOURNAL OF MAGNETIC RESONANCE IMAGING Gold, G. E., Fuller, S. E., Hargreaves, B. A., Stevens, K. J., Beaulieu, C. F. 2005; 21 (4): 476-481


    To evaluate three-dimensional driven equilibrium Fourier transform (3D-DEFT) for image quality and detection of articular cartilage lesions in the knee.We imaged 104 consecutive patients with knee pain with 3D-DEFT and proton density (PD-FSE) and T2-weighted (T2-FSE) fast spin echo. Twenty-four went on to arthroscopy. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) efficiency were measured. Subjective image quality, fat suppression, and cartilage thickness visibility were assessed. Cartilage lesions on 3D-DEFT and T2-FSE were compared with findings outlined in operative reports.SNR efficiency was higher for 3D-DEFT and PD-FSE than for T2-FSE (P < 0.02). 3D-DEFT and PD-FSE showed superior cartilage thickness visibility compared with T2-FSE (P < 0.02). T2-FSE showed better fat suppression and fewer image artifacts than 3D-DEFT (P < 0.04). 3D-DEFT had similar sensitivity and similar specificity for cartilage lesions compared with PD-FSE and T2-FSE.3D-DEFT provides excellent synovial fluid-to-cartilage contrast while preserving signal from cartilage, giving this method a high cartilage SNR. 3D-DEFT shows the full cartilage thickness better than T2-FSE. T2-FSE had superior fat saturation and fewer artifacts than 3D-DEFT. Overall, 3D-DEFT requires further technical development, but is a promising method for imaging articular cartilage.

    View details for DOI 10.1002/jhmi.20276

    View details for PubMedID 15779031

  • Magnetic resonance imaging of articular cartilage of the knee: Comparison between fat-suppressed three-dimensional SPGR imaging, fat-suppressed FSE imaging, and fat-suppressed three-dimensional DEFT imaging, and correlation with arthroscopy JOURNAL OF MAGNETIC RESONANCE IMAGING Yoshioka, H., Stevens, K., Hargreaves, B. A., Steines, D., Genovese, M., Dillingham, M. F., Winalski, C. S., Lang, P. 2004; 20 (5): 857-864


    To compare signal-to-noise ratios (S/N) and contrast-to-noise ratios (C/N) in various MR sequences, including fat-suppressed three-dimensional spoiled gradient-echo (SPGR) imaging, fat-suppressed fast spin echo (FSE) imaging, and fat-suppressed three-dimensional driven equilibrium Fourier transform (DEFT) imaging, and to determine the diagnostic accuracy of these imaging sequences for detecting cartilage lesions in osteoarthritic knees, as compared with arthroscopy.Two sagittal fat-suppressed FSE images (repetition time [TR] / echo time [TE], 4000/13 [FSE short TE] and 4000/39 [FSE long TE]), sagittal fat-suppressed three-dimensional SPGR images (60/5, 40 degrees flip angle), and sagittal fat-suppressed echo-planar three-dimensional DEFT images (400/21.2) were acquired in 35 knees from 28 patients with osteoarthritis of the knee. The S/N efficiencies (S/Neffs) of cartilage, synovial fluid, muscle, meniscus, bone marrow, and fat tissue, and the C/N efficiencies (C/Neffs) of these structures were calculated. Kappa values, exact agreement, sensitivity, specificity, positive predictive value, and negative predictive value were determined by comparison of MR grading with arthroscopic results.The synovial fluid S/Neff on fat-suppressed FSE short TE images, fat-suppressed FSE long TE images, and fat-suppressed three-dimensional DEFT images showed similar values. Fat-suppressed three-dimensional DEFT images showed the highest fluid-cartilage C/Neff of all sequences. All images showed fair to good agreement with arthroscopy (kappa, 0.615 in FSE short TE, 0.601 in FSE long TE, 0.583 in three-dimensional SPGR, and 0.561 in three-dimensional DEFT). Although the sensitivity of all sequences was high (100% in FSE short TE, FSE long TE, and DEFT; 96.7% in SPGR), specificity was relatively low (67.6% in FSE short TE and FSE long TE; 85.3% in SPGR; 58.3% in DEFT). The peripheral area of bone marrow edema or whole area of bone marrow edema on fat-suppressed FSE images was demonstrated as low or iso-signal intensity on fat-suppressed three-dimensional DEFT images.Fat-suppressed three-dimensional SPGR imaging and fat-suppressed FSE imaging showed high sensitivity and high negative predictive values, but relatively low specificity. The Kappa value and exact agreement was the highest on fat-suppressed FSE short TE images. Fat-suppressed three-dimensional DEFT images showed results similar to the conventional sequences.

    View details for DOI 10.1002/jmri.20193

    View details for Web of Science ID 000224762700017

    View details for PubMedID 15503323

  • Articular cartilage of knee: Normal patterns at MR imaging that mimic disease in healthy subjects and patients with osteoarthritis RADIOLOGY Yoshioka, H., Stevens, K., Genovese, M., Dillingham, M. F., Lang, P. 2004; 231 (1): 31-38


    To evaluate normal magnetic resonance (MR) imaging findings that may mimic articular cartilage diseases in healthy subjects and patients with osteoarthritis of the knee.Sagittal fat-suppressed intermediate-weighted fast spin-echo (FSE) (repetition time msec/echo time [TE] msec, 4,000/13), sagittal T2-weighted FSE (4,000/39), and sagittal fat-suppressed three-dimensional (3D) spoiled gradient-echo (SPGR) (60/5, 40 degrees flip angle) MR images were acquired in 28 patients and four volunteers. FSE images with a TE of 13 msec were considered "short-TE images"; those with a TE of 39 msec were considered "long-TE images." Presence of normal MR imaging appearance of articular cartilage was determined by one author. Contrast between cartilage and adjacent structures (meniscus, joint capsule, synovial fluid, muscle) was calculated in posterior regions of the femoral condyle on images obtained with each sequence; Wilcoxon signed rank testing was performed.The following appearances were observed in patients with knee osteoarthritis (on short-TE FSE, long-TE FSE, and SPGR MR images, respectively): (a) ambiguity of surface contour in posterior region of the femoral condylar cartilage (in zero, zero, and 20 patients), (b) linear area of high signal intensity in deep zone adjacent to subchondral bone of femoral condyle (in zero, zero, and 26 patients), (c) pseudolaminar appearance in posterior region of femoral condylar cartilage (in seven, nine, and 24 patients), (d) truncation artifact in patellofemoral compartment (in seven, six, and 27 patients), (e) susceptibility artifact on cartilage surface caused by air or metal (in three, three, and 11 patients), (f) decreased signal intensity in distal part of trochlear cartilage (in 28, 28, and 28 patients), (g) cartilage thinning adjacent to the anterior horn of the lateral meniscus (in 19, 19, and 21 patients), and (h) focal cartilage flattening in posterior region of femoral condyle (in 16, 16, and nine patients). Cartilage-meniscus and cartilage-synovial fluid contrast was significantly higher on fat-suppressed FSE than on fat-suppressed 3D SPGR MR images (P <.001).Fat-suppressed FSE and 3D SPGR MR images showed nonuniform signal intensity arising from articular cartilage and cartilage thinning, both of which could mimic disease.

    View details for DOI 10.1148/radiol.2311020453

    View details for Web of Science ID 000220394300006

    View details for PubMedID 15068938

  • Power Doppler ultrasound of rheumatoid synovitis: quantification of therapeutic response BRITISH JOURNAL OF RADIOLOGY Teh, J., Stevens, K., Williamson, L., Leung, J., McNally, E. G. 2003; 76 (912): 875-879


    The aim of this study is to quantify power Doppler assessment of therapeutic response in rheumatoid synovitis. 13 patients (6 male, 7 female) with rheumatoid arthritis, who had an acute exacerbation of small joint synovitis in the hands, were examined with quantitative power Doppler, before and after intravenous corticosteroid treatment. All patients were examined by a single radiologist, using an ATL HDI 5000 ultrasound machine (ATL, Boswell). The images were analysed using a specially developed software package (HDI Lab), which quantifies power Doppler signal. All patients improved clinically following treatment, which was reflected in functional disability scores, and in the C-reactive protein levels and erythrocyte sedimentation rate. In all cases, there was a significant decrease in synovial vascularity as measured by the mean amplitude of signal on quantitative power Doppler. Quantitative power Doppler may allow objective assessment of treatment in small joint synovitis.

    View details for DOI 10.1259/bjr/40466706

    View details for Web of Science ID 000188590400005

    View details for PubMedID 14711774

  • Imaging of the articular cartilage in osteoarthritis of the knee joint: 3D spatial-spectral spoiled gradient-echo vs. fat-suppressed 3D spoiled gradient-echo MR imaging JOURNAL OF MAGNETIC RESONANCE IMAGING Yoshioka, H., Alley, M., Steines, D., Stevens, K., Rubesova, E., Genovese, M., Dillingham, M. F., Lang, P. 2003; 18 (1): 66-71


    To compare three-dimensional (3D) spatial-spectral (SS) spoiled gradient-recalled acquisition in the steady state (SPGR) imaging with fat-suppressed 3D SPGR sequences in MR imaging of articular cartilage of the knee joint in patients with osteoarthritis.MR images of six patients with osteoarthritis of the knee were prospectively examined with a 1.5T MR scanner. For quantitative analyses, the signal-to-noise ratios, contrast-to-noise ratios, and contrast of cartilage and adjacent structures including meniscus, synovial fluid, muscle, fat tissue, and bone marrow were measured.In patients with osteoarthritis, 3DSS-SPGR images demonstrated higher spatial resolution and higher mean signal-to-noise (S/N) ratios (cartilage, 24.9; synovial fluid, 12.3; muscle, 20.7; meniscus, 21.6), with shorter acquisition times (7 minutes 20 seconds), when compared to fat-suppressed 3D SPGR images (cartilage, 22.3; synovial fluid, 10.8; muscle, 16.7; meniscus, 13.4).3DSS-SPGR imaging is a promising method for evaluating cartilage pathology in patients with osteoarthritis of the knee and has the potential to replace fat-suppressed 3D SPGR imaging.

    View details for DOI 10.1002/jmri.10320

    View details for PubMedID 12815641

  • Subchondral fractures in osteonecrosis of the femoral head: Comparison of radiography, CT, and MR imaging AMERICAN JOURNAL OF ROENTGENOLOGY Stevens, K., Tao, C., Lee, S. U., Salem, N., Vandevenne, J., Cheng, C., Neumann, G., Alexandre-Valentrin-Opran, Lang, P. 2003; 180 (2): 363-368


    Our objective was to compare the sensitivity of unenhanced radiography, CT, and MR imaging in revealing subchondral fractures.Forty-five subjects with stage I and stage II osteonecrosis of the femoral head were included in the study as part of a multicenter clinical trial to evaluate the effectiveness of recombinant human bone morphogenetic protein as an adjuvant treatment to core decompression. Patients were evaluated with radiography, CT, and MR imaging 6 and 12 months after surgery.At 6 months, 18 fractures were shown on CT scans, but only 12 were detected on radiographs and six, on MR images. At 12 months, 20 subchondral fractures were detected on CT scans, but only 17 were seen on radiographs and 11, on MR images. Compared with CT, MR imaging has a sensitivity and specificity of 38% and 100%, and unenhanced radiography has a sensitivity and specificity of 71% and 97%, respectively. On T2-weighted MR images, the subchondral fractures were visualized as crescentic high-signal-intensity lines, and in all patients, on the corresponding CT scans, the fracture clearly breached the femoral cortex.CT reveals more subchondral fractures in osteonecrosis of the femoral head than unenhanced radiography or MR imaging. The high-signal-intensity line seen on T2-weighted MR images appears to represent fluid accumulating in the subchondral fracture, which may indicate a breach in the overlying articular cartilage.

    View details for PubMedID 12540435

  • Gd-labeled liposomes for monitoring liposome-encapsulated chemotherapy: Quantification of regional uptake in tumor and effect on drug delivery Contrast Media Research Conference Rubesova, E., Berger, F., Wendland, M. F., Hong, K. L., Stevens, K. J., Gooding, C. A., Lang, P. ELSEVIER SCIENCE INC. 2002: S525–S527

    View details for PubMedID 12188328

  • Tumoral enthesopathy in psoriasis RHEUMATOLOGY Stevens, K. J., Smith, S. L., Preston, B. J., Deighton, C. 2001; 40 (3): 342-344

    View details for Web of Science ID 000167965200017

    View details for PubMedID 11285385

  • Imaging of plant-thorn synovitis SKELETAL RADIOLOGY Stevens, K. J., Theologis, T., McNally, E. G. 2000; 29 (10): 605-608


    We describe a case of plant-thorn synovitis of the elbow resulting from a thorn injury. This caused recurrent pain and swelling of the elbow over a 3-month period. A magnetic resonance imaging examination was initially requested to exclude septic arthritis, and demonstrated a joint effusion, synovitis, and a 2-cm linear opacity embedded in the synovium. Ultrasound was performed prior to surgery to confirm these findings and provide accurate localization of the thorn fragment, later removed at surgery. To our knowledge this is the first example of this condition that has been confirmed by radiological imaging prior to surgery.

    View details for Web of Science ID 000165478400010

    View details for PubMedID 11127686

  • Bilateral fractures of the middle phalanx of the middle finger in an adolescent climber AMERICAN JOURNAL OF SPORTS MEDICINE Chell, J., Stevens, K., Preston, B., Davis, T. R. 1999; 27 (6): 817-819

    View details for Web of Science ID 000083719300023

    View details for PubMedID 10569373

  • Pneumothorax post transthoracic biopsy: Incidence, detection and management J Diag Radiogr Imag Smith S, Stevens KJ, Manhire AR 1999; 2: 89 - 93
  • Is mammography of value in women with disseminated cancer of unknown origin? CLINICAL ONCOLOGY Stevens, K. J., Smith, S. L., Denley, H., Pinder, S. E., Evans, A. J., Chan, S. Y. 1999; 11 (2): 90-92


    Mammography is often requested to try to identify occult primary breast carcinoma in women with metastatic cancer of unknown primary site. This study aimed to investigate whether mammography is of use in these patients in identifying the breast as the origin of the metastatic disease. Thirty-one women with a working diagnosis of metastatic cancer underwent mammography in an attempt to determine the primary site. None of these women had a palpable breast mass. The site of presentation, pathological type of tumour, site of origin, and benefit of mammography and mammography-provoked biopsy were clarified for each patient. The patients were also followed up to determine survival. The commonest sites of presentation were lung (45%), lymph nodes (19%) and abdomen (16%). The primary sites of these cancers were identified with confidence in 27 patients (87%). The commonest known primary tumour sites were lung (45%), breast (16%) and ovary (16%). Abnormal mammograms were detected in four patients (13%), but three of these did not have breast cancer. In one, the site of origin remained indeterminate, as either breast or lung. Five (16%) had a confident diagnosis of breast carcinoma; all of these women had normal mammograms. We conclude that mammography in women presenting with metastatic disease from an unknown primary site is unhelpful and is not recommended. Furthermore, we could not demonstrate its value in women presenting with axillary lymphadenopathy.

    View details for Web of Science ID 000083698700005

    View details for PubMedID 10378633

  • Magnetic resonance imaging to customize lower limb modelling in cerebral palsy. Gait and Posture Harrington M, Stevens K, Thompson N, O'Connor J, Theologic T. 1999; 10: 84 - 85
  • CT imaging and three-dimensional reconstructions of shoulders with anterior glenohumeral instability CLINICAL ANATOMY Stevens, K. J., Preston, B. J., Wallace, W. A., Kerslake, R. W. 1999; 12 (5): 326-336


    Glenohumeral instability is a common occurrence following anterior dislocation of the shoulder joint, particularly in young men. The bony abnormalities encountered in patients with glenohumeral instability can be difficult to detect with conventional radiography, even with special views. The aim of our study was to evaluate the bony abnormalities associated with glenohumeral instability using CT imaging with 3-D reconstruction images. We scanned 11 patients with glenohumeral instability, one with bilateral symptoms; 10 were male, one female, and their ages ranged from 18-66 years. Contiguous 3 mm axial slices of the glenohumeral joint were taken at 2 mm intervals using a Siemens Somatom CT scanner. In the 12 shoulders imaged, we identified four main abnormalities. A humeral-head defect or Hill-Sachs deformity was seen in 83% cases, fractures of the anterior glenoid rim in 50%, periosteal new bone formation secondary to capsular stripping in 42%, and loose bone fragments in 25%. Manipulation of the 3-D images enabled the abnormalities to be well seen in all cases, giving a graphic visualization of the joint, and only two 3-D images were needed to demonstrate all the necessary information. We feel that CT is the imaging modality most likely to show all the bone abnormalities associated with glenohumeral instability. These bony changes may lead to the correct inference of soft tissue abnormalities making more invasive examinations such as arthrography unnecessary.

    View details for Web of Science ID 000082326600003

    View details for PubMedID 10462730

  • Magnetic resonance imaging of elephantiasis neuromatosa SKELETAL RADIOLOGY Stevens, K. J., Ludman, C. N., Sully, L., Preston, B. J. 1998; 27 (12): 696-701


    We present the case of a 43-year-old man with neurofibromatosis type 1 who developed elephantiasis neuromatosa of his left leg. The gross limb enlargement was extremely disfiguring, and resulted in such severe disability that he was only able to walk a very short distance using crutches. Previous debulking procedures had resulted in massive blood loss, and prior to attempting further surgical intervention MRI studies were requested. Taking advantage of the excellent tissue characterisation and multiplanar imaging capabilities of MRI, we were able to assess the extent of soft tissue and osseous involvement. The use of recently developed MR angiographic sequences enabled us to non-invasively provide detailed images to assess the relationship of the lesions to the major vessels, as well as the vascular supply and angiographic features of the lesions themselves. This article describes our MRI-based findings, which precluded debulking surgery in this unusual manifestation of neurofibromatosis.

    View details for Web of Science ID 000077909100009

    View details for PubMedID 9921933

  • Brown-Sequard syndrome due to traumatic brachial plexus root avulsion INJURY-INTERNATIONAL JOURNAL OF THE CARE OF THE INJURED Stephen, A. B., Stevens, K., Craigen, M. A., Kerslake, R. W. 1997; 28 (8): 557-558

    View details for Web of Science ID 000072481800016

    View details for PubMedID 9616398

  • Pseudomyxoma extraperitonei: A lethal complication of mucinous adenocarcinoma of the appendix AMERICAN JOURNAL OF GASTROENTEROLOGY Stevens, K. J., Dunn, W. K., Balfour, T. 1997; 92 (10): 1920-1922


    We report the unusual case of a 56-yr-old man who presented with an appendix abscess. This abscess failed to respond to standard treatment, and recurred despite operative intervention. A colocutaneous fistula developed, which initially discharged frank pus, then began discharging mucus via two cutaneous sinuses. No evidence of malignancy was detected from either repeat curettings or a diagnostic laparotomy. One and a half years after the initial presentation, histologic examination finally revealed mucinous adenocarcinoma of the appendix. We postulate that this malignancy in a retrocecal appendix resulted in a mucocele, which ruptured into the retroperitoneal space and drained via cutaneous sinuses, so-called pseudomyxoma extraperitonei. The patient declined further surgical intervention, and despite initial control by radiotherapy, the tumor spread locally to involve the entire right lower quadrant of the abdomen. The patient eventually died 39 months after the initial presentation.

    View details for Web of Science ID A1997XZ84800035

    View details for PubMedID 9382067

  • Bilateral fracture dislocation of the sacroiliac joint SKELETAL RADIOLOGY Stevens, K. J., Preston, B. J., Hahn, D. M. 1997; 26 (9): 556-558


    We present a rare case of a 27-year-old man sustaining a bilateral fracture dislocation of the sacroiliac joints without disruption of the anterior pelvis, following a fall from a height. Reconstructed images in the coronal plane and three-dimensional CT images were invaluable in the diagnosis and assessment of this injury.

    View details for Web of Science ID A1997XY82100010

    View details for PubMedID 9342818

  • The ultrasound appearances of galactocoeles BRITISH JOURNAL OF RADIOLOGY Stevens, K., Burrell, H. C., Evans, A. J., Sibbering, D. M. 1997; 70: 239-241


    Galactocoeles are an uncommon cause of breast masses, usually occurring in lactating women. The purpose of this study was to review the ultrasound (US) features of galactocoeles presenting to the Nottingham Breast Unit. Eight women with galactocoeles were scanned during 1994 and 1995. All the scans were abnormal, 50% of lesions were cystic or multicystic, 37% mixed cystic/solid and 13% appeared solid. A fat-fluid level was seen in only one case. Two of the cystic/solid lesions had ill defined solid components, raising the possibility of an intracystic carcinoma. All cases were confirmed by the aspiration of milk and clinical resolution following aspiration.

    View details for Web of Science ID A1997WP55800003

    View details for PubMedID 9166046

  • Diagnostic echographique d'une galactocele Journal Francais d'Echographie Stevens KJ, Burrell HC, Evans A, Sibbering DM 1997; 5: 47 - 48
  • False aneurysm of a lumbar artery following vertebral biopsy. European spine journal Stevens, K. J., Gregson, R. H., Kerslake, R. W. 1997; 6 (3): 205-207


    Vertebral body biopsy is regarded as a simple and relatively safe technique, with a low complication rate. We report the case of an 80-year-old man who developed a false aneurysm of a lumbar artery following biopsy of the fourth lumbar vertebra.

    View details for PubMedID 9258641

    View details for PubMedCentralID PMC3454612

  • FEMORAL NERVE PALSY - AN UNUSUAL COMPLICATION OF ANTERIOR LUMBAR INTERBODY FUSION SPINE Papastefanou, S. L., Stevens, K., Mulholland, R. C. 1994; 19 (24): 2842-2844


    Compression neuropathy of the femoral nerve has been reported as an uncommon complication of bleeding into the iliopsoas muscle.The authors detected anatomic reasons of direct injury to the femoral nerve at the lower lumbar level.Keeping the hip in extension during the course of carrying out anterior fusion on a previously failed posterior fusion was considered another causative factor of femoral nerve injury. Anatomical dissection confirmed the likelihood of this injury being produced in this situation.Femoral nerve traction and compression can occur after prolonged compression of the nerve within the psoas muscle stretched between an immobile lower lumbar spine and the lesser trochanter when the hip is kept in extension. In the patients described no other reasons for direct or indirect injury were identified.Although uncommon, the complication should be kept in mind. It can be avoided by intraoperative hip flexion.

    View details for Web of Science ID A1994PY22600020

    View details for PubMedID 7899989

  • Sciatic nerve palsy caused by haematoma from iliac bone graft donor site. European spine journal Stevens, K. J., Banuls, M. 1994; 3 (5): 291-293


    A 27-year-old woman developed a haematoma-related compressive neuropathy of the right sciatic nerve following the harvesting of a bone graft from the posterior aspect of the right iliac crest. The nerve was compressed in an enclosed compartment between the sciatic notch and the piriformis muscle, which is thought to be involved in the piriformis syndrome. The symptoms improved once the haematoma was evacuated, and this complication stresses the importance of adequate haemostasis of the area from which the bone graft is taken.

    View details for PubMedID 7866855

  • Iliolumbar hernia following bone grafting. European spine journal Stevens, K. J., Banuls, M. 1994; 3 (2): 118-119


    A 40-year-old man developed a lumbar hernia through an iliac bone graft donor site. The defect was repaired using an autologous bone graft reinforced by titanium mesh.

    View details for PubMedID 7874549



    The incidence of abdominal aortic aneurysms (AAAs) is increasing, especially in the elderly. This trend has been observed in the United Kingdom, USA, Australia, and Sweden. The increase can be explained partly by an enhanced awareness of the condition and partly by the rising numbers of elderly in the population. In addition, improved diagnostic techniques have enabled earlier detection of aneurysms. But this does not fully explain why we are seeing such a high prevalence of the condition. Evidence for the increase can be obtained from a number of sources, such as routine mortality statistics.

    View details for Web of Science ID A1993MA78800012

    View details for PubMedID 8260341

  • A study of Peroneus Tertius British Journal of Clinical Anatomy Stevens K, Platt A, Ellis H 1992; 6 (6): 106 -110


    Saliva aldosterone concentration was measured in samples collected at hourly intervals from healthy pregnant women (approximately 26 and 36 weeks gestation) who were going about their normal daily activities, and from some women hospitalized for disorders of pregnancy. In the healthy women diurnal saliva aldosterone fluctuated considerably, the highest values being 2-22 times the lowest on a given day. Because of the known correlation between saliva and plasma aldosterone concentrations we believe that the fluctuating salivary level is indicative of fluctuating plasma levels and that this is due to the intermittent secretion of aldosterone. The rate of decline of saliva aldosterone from peak levels indicated a half life (t 1/2) of 72 (SD 31) min which was not significantly different from that in non-pregnant subjects. The temporal pattern of saliva aldosterone suggests an enhanced response of the zona glomerulosa to the factors that cause aldosterone secretion to fluctuate in non-pregnant subjects, rather than the development of a more potent stimulus to the zona glomerulosa during pregnancy. In addition to hour-to-hour variation there is also substantial day-to-day variation, so that estimation of aldosterone in a single sample of saliva or plasma is of little value during pregnancy. The mean diurnal aldosterone concentration can be estimated from five saliva samples so this measurement presents a convenient technique for the assessment of aldosterone status in pregnancy. In contrast to healthy pregnancy, a patient with pre-eclampsia at 39 weeks gestation showed no elevation of saliva aldosterone above non-pregnant levels at any time during the day.

    View details for Web of Science ID A1989T064100014

    View details for PubMedID 2923844