Seena Dehkharghani MD FAHA

All Publications

• Using Data-Driven Methods to Improve Brain Blood Flow Measurements in Cerebrovascular Disease with Dynamic Imaging. AJNR. American journal of neuroradiology Dogra, S., Wang, X., Gee, J. M., Zhu, Y., Ishida, K., Dehkharghani, S. 2025

  Abstract

  Cerebrovascular reactivity (CVR) is a widely studied biomarker of cerebral hemodynamics, commonly used in risk stratification and treatment planning in patients with steno-occlusive disease (SOD). Conventional use relies on normalization of estimates to contralateral hemisphere reference values, which is unsuitable for bilateral or indeterminate distributions of disease. We report upon a custom data-driven approach leveraging random forest classifiers (RFc) to identify candidate voxels for normalization in order to facilitate interrogation outside conditions of known unilateral SOD MATERIALS AND METHODS: We retrospectively analyzed 16 patients with unilateral SOD who underwent acetazolamide-augmented BOLD-MRI and DSC perfusion. Three RFc models were trained using leave-one-out cross-validation (LOOCV) to identify candidate voxels brain-wide whose CVR were within 10% of the normal hemispheric median: i. all voxels; ii. gray matter only; and iii. white matter only. Model input features included time-to-maximum (Tmax), mean transit time (MTT), cerebral blood flow (CBF), and cerebral blood volume (CBV) from contemporaneous DSC. The median model-predicted reference CVR (CVRref) was compared to ground-truth medians in LOOCV, and its impact on threshold-based volumetric classification of CVR reduction assessed.RFc models effectively predicted ground-truth CVR voxels, achieving median absolute percent differences of 12.8% (IQR: 5.0%-18.9%) using all voxels, 11.3% (IQR: 9.3%-16.1%) for gray matter, and 9.8% (IQR: 4.4%-16.9%) for white matter. Volumetric estimates of CVR reduction across thresholds for the models revealed excellent agreement between ground-truth and model estimates without statistically significant differences (p>0.01), excepting lowest white matter CVR thresholds. Model use in a small pilot deployment of bilateral SOD cases demonstrated the potential utility, enabling voxel-wise CVR assessment without reliance on contralateral reference.We present a novel data-driven approach for normalizing CVR maps in patients with bilateral or indeterminate SOD. Using an RFc, our method provides an individualized, brain-wide reference CVR, expanding the utility of CVR estimates beyond the typical constraints of unilateral disease, and with potential application to other, similarly constrained scenarios such as for SPECT or PET hemodynamic studies.CVR = cerebrovascular reactivity; RFc = random forest classifier; SOD = steno-occlusive disease.

  View details for DOI 10.3174/ajnr.A8813

  View details for PubMedID 40262947

• An experimental system for detection and localization of hemorrhage using ultra-wideband microwaves with deep learning COMMUNICATIONS ENGINEERING Hedayati, E., Safari, F., Verghese, G., Ciancia, V. R., Sodickson, D. K., Dehkharghani, S., Alon, L. 2024; 3 (1): 126

  Abstract

  Stroke is a leading cause of mortality and disability. Emergent diagnosis and intervention are critical, and predicated upon initial brain imaging; however, existing clinical imaging modalities are generally costly, immobile, and demand highly specialized operation and interpretation. Low-energy microwaves have been explored as a low-cost, small form factor, fast, and safe probe for tissue dielectric properties measurements, with both imaging and diagnostic potential. Nevertheless, challenges inherent to microwave reconstruction have impeded progress, hence conduction of microwave imaging remains an elusive scientific aim. Herein, we introduce a dedicated experimental framework comprising a robotic navigation system to translate blood-mimicking phantoms within a human head model. An 8-element ultra-wideband array of modified antipodal Vivaldi antennas was developed and driven by a two-port vector network analyzer spanning 0.6-9.0 GHz at an operating power of 1 mW. Complex scattering parameters were measured, and dielectric signatures of hemorrhage were learned using a dedicated deep neural network for prediction of hemorrhage classes and localization. An overall sensitivity and specificity for detection >0.99 was observed, with Rayleigh mean localization error of 1.65 mm. The study establishes the feasibility of a robust experimental model and deep learning solution for ultra-wideband microwave stroke detection.

  View details for DOI 10.1038/s44172-024-00259-4

  View details for Web of Science ID 001478563600001

  View details for PubMedID 39242634

  View details for PubMedCentralID PMC11379885

• Correspondence on: 'Viz LVO versus Rapid LVO in detection of large vessel occlusion on CT angiography for acute stroke' by Delora <i>et al</i> JOURNAL OF NEUROINTERVENTIONAL SURGERY Yedavalli, V. S., Dehkharghani, S., Clemente, J. 2025; 17 (3): 334

  View details for DOI 10.1136/jnis-2024-022342

  View details for Web of Science ID 001309606400001

  View details for PubMedID 39237155

• Performance of RAPID noncontrast CT stroke platform in large vessel occlusion and intracranial hemorrhage detection. Frontiers in neurology Yedavalli, V., Heit, J. J., Dehkharghani, S., Haerian, H., Mcmenamy, J., Honce, J., Timpone, V. M., Harnain, C., Kesselman, A., Filly, A., Beardsley, A., Sakamoto, B., Song, C., Montuori, J., Navot, B., Mena, F. V., Giurgiutiu, D. V., Kitamura, F., Lima, F. O., Silva, H., Mont'Alverne, F. J., Albers, G. 2023; 14: 1324088

  Abstract

  Noncontrast CT (NCCT) is used to evaluate for intracerebral hemorrhage (ICH) and ischemia in acute ischemic stroke (AIS). Large vessel occlusions (LVOs) are a major cause of AIS, but challenging to detect on NCCT.The purpose of this study is to evaluate an AI software called RAPID NCCT Stroke (RAPID, iSchemaView, Menlo Park, CA) for ICH and LVO detection compared to expert readers.In this IRB approved retrospective, multicenter study, stand-alone performance of the software was assessed based on the consensus of 3 neuroradiologists and sensitivity and specificity were determined. The platform's performance was then compared to interpretation by readers comprised of eight general radiologists (GR) and three neuroradiologists (NR) in detecting ICH and hyperdense vessel sign (HVS) indicating LVO.A total of 244 cases were included. Of the 244, 115 were LVOs and 26 were ICHs. One hundred three cases did not have LVO nor ICH. Stand-alone performance of the software demonstrated sensitivities and specificities of 96.2 and 99.5% for ICH and 63.5 and 95.1% for LVO detection. Compared to all 11 readers and eight GR readers only respectively, the software demonstrated superiority, achieving significantly higher sensitivities (63.5% versus 43.6%, p < 0.0001 and 63.5% versus 40.9%, p = 0.001).The RAPID NCCT Stroke platform demonstrates superior performance to radiologists for detecting LVO from a NCCT. Use of this software platform could lead to earlier LVO detection and expedited transfer of these patients to a thrombectomy capable center.

  View details for DOI 10.3389/fneur.2023.1324088

  View details for PubMedID 38156093

  View details for PubMedCentralID PMC10753184

• Decreasing false-positive detection of intracranial hemorrhage (ICH) using RAPID ICH 3. Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association Sreekrishnan, A., Giurgiutiu, D., Kitamura, F., Martinelli, C., Abdala, N., Haerian, H., Dehkharghani, S., Kwok, K., Yedavalli, V., Heit, J. J. 2023; 32 (12): 107396

  Abstract

  INTRODUCTION: The prompt detection of intracranial hemorrhage (ICH) on a non-contrast head CT (NCCT) is critical for the appropriate triage of patients, particularly in high volume/high acuity settings. Several automated ICH detection tools have been introduced; however, at present, most suffer from suboptimal specificity leading to false-positive notifications.METHODS: NCCT scans from 4 large databases were evaluated for the presence of an ICH (IPH, IVH, SAH or SDH) of >0.4 ml using fully-automated RAPID ICH 3.0 as compared to consensus detection from at least two neuroradiology experts. Scans were excluded for (1) severe CT artifacts, (2) prior neurosurgical procedures, or (3) recent intravenous contrast. ICH detection accuracy, sensitivity, specificity, positive predictive value, negative predictive value, and positive and negative likelihood ratios by were determined.RESULTS: A total of 881 studies were included. The automated software correctly identified 453/463 ICH-positive cases and 416/418 ICH-negative cases, resulting in a sensitivity of 97.84% and specificity 99.52%, positive predictive value 99.56%, and negative predictive value 97.65% for ICH detection. The positive and negative likelihood ratios for ICH detection were similarly favorable at 204.49 and 0.02 respectively. Mean processing time was <40 seconds.CONCLUSIONS: In this large data set of nearly 900 patients, the automated software demonstrated high sensitivity and specificity for ICH detection, with rare false-positives.

  View details for DOI 10.1016/j.jstrokecerebrovasdis.2023.107396

  View details for PubMedID 37883825

• Imaging Factors Associated With Poor Outcome in Patients With Basilar Artery Occlusion Treated With Endovascular Thrombectomy STROKE-VASCULAR AND INTERVENTIONAL NEUROLOGY Heit, J. J., Mlynash, M., Cereda, C. W., Yuen, N., Lansberg, M. G., Bianco, G., Christensen, S., Qureshi, A. Y., Hinduja, A., Dehkharghani, S., Goldman-Yassen, A. E., Hsieh, K., Giurgiutiu, D., Gibson, D., Carrera, E., Alemseged, F., Faizy, T. D., Fiehler, J., Pileggi, M., Campbell, B., Albers, G. W. 2023; 3 (3)

  View details for DOI 10.1161/SVIN.122.000767

  View details for Web of Science ID 001162312700023

• Cerebral Perfusion Imaging And Posterior Circulation ASPECTS Identify Stroke Patients Who Benefit From Basilar Artery Thrombectomy Heit, J. J., Bianco, G., Mlynash, M., Yuen, N., Qureshi, A. Y., Hinduja, A., Dehkharghani, S., Goldman-Yassen, A., Hsieh, K., Giurgiutiu, D., Gibson, D., Carrera, E., Alemseged, F., Faizy, T. D., Fiehler, J., Pileggi, M., Lansberg, M. G., Campbell, B., Albers, G. W., Cereda, C. W. LIPPINCOTT WILLIAMS & WILKINS. 2022

  View details for DOI 10.1161/str.53.suppl_1.126

  View details for Web of Science ID 000788100600123

• Perfusion Imaging Predicts Favorable Outcomes after Basilar Artery Thrombectomy. Annals of neurology Cereda, C. W., Bianco, G., Mlynash, M., Yuen, N., Qureshi, A. Y., Hinduja, A., Dehkharghani, S., Goldman-Yassen, A. E., Hsieh, K. L., Giurgiutiu, D., Gibson, D., Carrera, E., Alemseged, F., Faizy, T. D., Fiehler, J., Pileggi, M., Campbell, B., Albers, G. W., Heit, J. J. 2021

  Abstract

  OBJECTIVE: Perfusion imaging identifies anterior circulation stroke patients who respond favorably to endovascular thrombectomy (ET), but its role in basilar occlusion (BAO) is unknown. We hypothesized that BAO patients with limited regions of severe hypoperfusion (Time-to-maximum [Tmax] delay >10 seconds) would have a favorable response to ET compared to patients with more extensive regions involved.METHODS: We performed a multicenter retrospective cohort study of BAO patients with perfusion imaging prior to ET. We pre-specified a Critical Area Perfusion Score (CAPS; 0-6 points), which quantified severe hypoperfusion (Tmax >10s) in cerebellum (1 point/hemisphere), pons (2 points), midbrain and/or thalamus (2 points). Patients were dichotomized into favorable (CAPS≤3) and unfavorable (CAPS>3) groups. The primary outcome was a favorable functional outcome 90-days after ET (modified Rankin Scale [mRS] 0-3).RESULTS: 103 patients were included. CAPS≤3 patients (87%) had a lower median NIHSS (12.5 [IQR 7-22]) compared to CAPS>3 patients (13%) (23 [IQR 19-36]; p=0.01). Reperfusion was achieved in 84% of all patients with no difference between CAPS groups (p=0.42). 64% of reperfused CAPS≤3 patients had a favorable outcome compared to 8% of non-reperfused CAPS≤3 patients (OR=21.0 [95% CI 2.6-170]; p<0.001). No CAPS>3 patients had a favorable outcome, regardless of reperfusion. In a multivariable regression analysis, CAPS≤3 was a robust independent predictor of favorable outcome after adjustment for reperfusion, age, and pre-ET NIHSS (OR 39.25 [95% CI 1.34->999)]; p=0.04).INTERPRETATION: BAO patients with limited regions of severe hypoperfusion had a favorable response to reperfusion following ET. However, patients with more extensive regions of hypoperfusion in critical brain regions did not benefit from endovascular reperfusion. This article is protected by copyright. All rights reserved.

  View details for DOI 10.1002/ana.26272

  View details for PubMedID 34786756

• Penumbra Consumption Rates Based on Time-to-Maximum Delay and Reperfusion Status: A Post Hoc Analysis of the DEFUSE 3 Trial. Stroke Yaghi, S., Raz, E., Dehkharghani, S., Riina, H., McTaggart, R., Jayaraman, M., Prabhakaran, S., Liebeskind, D. S., Khatri, P., Mac Grory, B., Al-Mufti, F., Lansberg, M., Albers, G., de Havenon, A. 2021: STROKEAHA120033806

  Abstract

  BACKGROUND AND PURPOSE: In patients with acute large vessel occlusion, the natural history of penumbral tissue based on perfusion time-to-maximum (Tmax) delay is not well established in relation to late-window endovascular thrombectomy. In this study, we sought to evaluate penumbra consumption rates for Tmax delays in patients with large vessel occlusion evaluated between 6 and 16 hours from last known normal.METHODS: This is a post hoc analysis of the DEFUSE 3 trial (The Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke), which included patients with an acute ischemic stroke due to anterior circulation occlusion within 6 to 16 hours of last known normal. The primary outcome is percentage penumbra consumption, defined as (24-hour magnetic resonance imaging infarct volume-baseline core infarct volume)/(Tmax 6 or 10 s volume-baseline core volume). We stratified the cohort into 4 categories based on treatment modality and Thrombolysis in Cerebral Infarction (TICI score; untreated, TICI 0-2a, TICI 2b, and TICI3) and calculated penumbral consumption rates in each category.RESULTS: We included 141 patients, among whom 68 were untreated. In the untreated versus TICI 3 patients, a median (interquartile range) of 53.7% (21.2%-87.7%) versus 5.3% (1.1%-14.6%) of penumbral tissue was consumed based on Tmax >6 s (P<0.001). In the same comparison for Tmax>10 s, we saw a difference of 165.4% (interquartile range, 56.1%-479.8%) versus 25.7% (interquartile range, 3.2%-72.1%; P<0.001). Significant differences were not demonstrated between untreated and TICI 0-2a patients for penumbral consumption based on Tmax >6 s (P=0.52) or Tmax >10 s (P=0.92).CONCLUSIONS: Among extended window endovascular thrombectomy patients, Tmax >10-s mismatch volume may comprise large volumes of salvageable tissue, whereas nearly half the Tmax >6-s mismatch volume may remain viable in untreated patients at 24 hours.

  View details for DOI 10.1161/STROKEAHA.120.033806

  View details for PubMedID 34157865

• Prediction of Infarct Volume at the 24 Hours after Late Window Presentation with Perfusion Imaging in Patients with Anterior Circulation Large Vessel Occlusion Agarwal, S., Raz, E., Dehkharghani, S., Christensen, S., Lansberg, M., Yaghi, S., de Havenon, A. LIPPINCOTT WILLIAMS & WILKINS. 2021

  View details for Web of Science ID 000729283602208

• Prediction of Infarct Volume at the 24 Hours After Late Window Presentation With Perfusion Imaging in Patients With Anterior Circulation Large Vessel Occlusion Agarwal, S., Raz, E., Dehkharghani, S., Christensen, S., Lansberg, M. G., Albers, G., Yaghi, S., De Havenon, A. H. LIPPINCOTT WILLIAMS & WILKINS. 2021

  View details for DOI 10.1161/str.52.suppl_1.P505

  View details for Web of Science ID 000670883500620

• RAPID-LVO for Automated Detection of Intracranial Large Vessel Occlusion in Ct Angiography of the Brain. Dehkharghani, S., Lansberg, M. G., Venkatsubramanian, C., Cereda, C. W., Lima, F. O., Coelho, H., Rocha, F. A., Qureshi, A. Y., Haerian, H. D., Montalverne, F., Copeland, K., Heit, J. LIPPINCOTT WILLIAMS & WILKINS. 2021

  View details for DOI 10.1161/str.52.suppl_1.P337

  View details for Web of Science ID 000670883500454

• Penumbra Consumption Rates Based on T Max Delay and Reperfusion Status: A Post-Hoc Analysis of the Defuse-3 Trial Yaghi, S., Raz, E., Dehkharghani, S., Riina, H., McTaggart, R., Jayaraman, M., Prabhakaran, S., Liebeskind, D. S., Khatri, P., Mac Grory, B. C., Lansberg, M. G., Albers, G. W., De Havenon, A. H. LIPPINCOTT WILLIAMS & WILKINS. 2021

  View details for DOI 10.1161/str.52.suppl_1.31

  View details for Web of Science ID 000670883500031

• High-Performance Automated Anterior Circulation CT Angiographic Clot Detection in Acute Stroke: A Multireader Comparison. Radiology Dehkharghani, S. n., Lansberg, M. n., Venkatsubramanian, C. n., Cereda, C. n., Lima, F. n., Coelho, H. n., Rocha, F. n., Qureshi, A. n., Haerian, H. n., Mont'Alverne, F. n., Copeland, K. n., Heit, J. n. 2021: 202734

  Abstract

  Background Identification of large vessel occlusion (LVO) is critical to the management of acute ischemic stroke and prerequisite to endovascular therapy in recent trials. Increasing volumes and data complexity compel the development of fast, reliable, and automated tools for LVO detection to facilitate acute imaging triage. Purpose To investigate the performance of an anterior circulation LVO detection platform in a large mixed sample of individuals with and without LVO at cerebrovascular CT angiography (CTA). Materials and Methods In this retrospective analysis, CTA data from recent cerebrovascular trials (CRISP [ClinicalTrials.gov NCT01622517] and DASH) were enriched with local repositories from 11 worldwide sites to balance demographic and technical variables in LVO-positive and LVO-negative examinations. CTA findings were reviewed independently by two neuroradiologists from different institutions for intracranial internal carotid artery (ICA) or middle cerebral artery (MCA) M1 LVO; these observers were blinded to all clinical variables and outcomes. An automated analysis platform was developed and tested for prediction of LVO presence and location relative to reader consensus. Discordance between readers with respect to LVO presence or location was adjudicated by a blinded tertiary reader at a third institution. Sensitivity, specificity, and receiver operating characteristics were assessed by an independent statistician, and subgroup analyses were conducted. Prespecified performance thresholds were set at a lower bound of the 95% CI of sensitivity and specificity of 0.8 or greater at mean times to notification of less than 3.5 minutes. Results A total of 217 study participants (mean age, 64 years ± 16 [standard deviation]; 116 men; 109 with positive findings of LVO) were evaluated. Prespecified performance thresholds were exceeded (sensitivity, 105 of 109 [96%; 95% CI: 91, 99]; specificity, 106 of 108 [98%; 95% CI: 94, 100]). Sensitivity and specificity estimates across age, sex, location, and vendor subgroups exceeded 90%. The area under the receiver operating characteristic curve was 99% (95% CI: 97, 100). Mean processing and notification time was 3 minutes 18 seconds. Conclusion The results confirm the feasibility of fast automated high-performance detection of intracranial internal carotid artery and middle cerebral artery M1 occlusions. © RSNA, 2021 See also the editorial by Kloska in this issue.

  View details for DOI 10.1148/radiol.2021202734

  View details for PubMedID 33434110

• The Effect of Hyperglycemia on Infarct Growth after Reperfusion: An Analysis of the DEFUSE 3 trial. Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association Yaghi, S., Dehkharghani, S., Raz, E., Jayaraman, M., Tanweer, O., Grory, B. M., Henninger, N., Lansberg, M. G., Albers, G. W., Havenon, A. d. 2020; 30 (1): 105380

  Abstract

  BACKGROUND AND PURPOSE: Brain infarct growth, despite successful reperfusion, decreases the likelihood of good functional outcome after ischemic stroke. In patients undergoing reperfusion, admission glucose is associated with poor outcome but the effect of glucose level on infarct growth is not well studied.MATERIALS AND METHODS: This is a secondary analysis of the DEFUSE 3 trial. The primary predictor was baseline glucose level and the primary outcome is the change of the ischemic core volume from the baseline to 24-hour follow-up imaging (∆core), transformed as a cube root to reduce right skew. We included DEFUSE 3 patients who were randomized to endovascular therapy, had perfusion imaging data at baseline, an MRI at 24 hours, and who achieved TICI 2b or 3. Linear regression models, both unadjusted and adjusted, were fit to the primary outcome and all models included the baseline core volume as a covariate to normalize ∆core.RESULTS: We identified 62 patients who met our inclusion criteria. The mean age was 68.1±13.1 (years), 48.4% (30/62) were men, and the median (IQR) cube root of ∆core was 2.8 (2.0-3.8) mL. There was an association between baseline glucose level and normalized ∆core in unadjusted analysis (beta coefficient 0.010, p = 0.01) and after adjusting for potential confounders (beta coefficient 0.008, p = 0.03).CONCLUSION: In acute ischemic stroke patients with large vessel occlusion undergoing successful endovascular reperfusion, baseline hyperglycemia is associated with infarction growth. Further study is needed to establish potential neuroprotective benefits of aggressive glycemic control prior to and after reperfusion.

  View details for DOI 10.1016/j.jstrokecerebrovasdis.2020.105380

  View details for PubMedID 33166769

• Fast Automatic Detection of Large Vessel Occlusions on CT Angiography. Stroke Amukotuwa, S. A., Straka, M., Dehkharghani, S., Bammer, R. 2019: STROKEAHA119027076

  Abstract

  Background and Purpose- Accurate and rapid detection of anterior circulation large vessel occlusion (LVO) is of paramount importance in patients with acute stroke due to the potentially rapid infarction of at-risk tissue and the limited therapeutic window for endovascular clot retrieval. Hence, the optimal threshold of a new, fully automated software-based approach for LVO detection was determined, and its diagnostic performance evaluated in a large cohort study. Methods- For this retrospective study, data were pooled from: 2 stroke trials, DEFUSE 2 (n=62; 07/08-09/11) and DEFUSE 3 (n=213; 05/17-05/18); a cohort of endovascular clot retrieval candidates (n=82; August 2, 2014-August 30, 2015) and normals (n=111; June 6, 2017-January 28, 2019) from a single quaternary center; and code stroke patients (n=501; January 1, 2017-December 31, 2018) from a single regional hospital. All CTAs were assessed by the automated algorithm. Consensus reads by 2 neuroradiologists served as the reference standard. ROC analysis was used to assess diagnostic performance of the algorithm for detection of (1) anterior circulation LVOs involving the intracranial internal carotid artery or M1 segment middle cerebral artery (M1-MCA); (2) anterior circulation LVOs and proximal M2 segment MCA (M2-MCA) occlusions; and (3) individual segment occlusions. Results- CTAs from 926 patients (median age 70 years, interquartile range: 58-80; 422 females) were analyzed. Three hundred ninety-five patients had an anterior circulation LVO or M2-MCA occlusion (National Institutes of Health Stroke Scale 14 [median], interquartile range: 9-19). Sensitivity and specificity were 97% and 74%, respectively, for LVO detection, and 95% and 79%, respectively, when M2 occlusions were included. On analysis by occlusion site, sensitivities were 90% (M2-MCA), 97% (M1-MCA), and 97% (intracranial internal carotid artery) with corresponding area-under-the-ROC-curves of 0.874 (M2), 0.962 (M1), and 0.997 (intracranial internal carotid artery). Conclusions- Intracranial anterior circulation LVOs and proximal M2 occlusions can be rapidly and reliably detected by an automated detection tool, which may facilitate intra- and inter-instutional workflows and emergent imaging triage in the care of patients with stroke.

  View details for DOI 10.1161/STROKEAHA.119.027076

  View details for PubMedID 31679501

• Automated Detection of Intracranial Large Vessel Occlusions on Computed Tomography Angiography. Stroke Amukotuwa, S. A., Straka, M., Smith, H., Chandra, R. V., Dehkharghani, S., Fischbein, N. J., Bammer, R. 2019: STROKEAHA119026259

  Abstract

  Background and Purpose- Endovascular thrombectomy is highly effective in acute ischemic stroke patients with an anterior circulation large vessel occlusion (LVO), decreasing morbidity and mortality. Accurate and prompt identification of LVOs is imperative because these patients have large volumes of tissue that are at risk of infarction without timely reperfusion, and the treatment window is limited to 24 hours. We assessed the accuracy and speed of a commercially available fully automated LVO-detection tool in a cohort of patients presenting to a regional hospital with suspected stroke. Methods- Consecutive patients who underwent multimodal computed tomography with thin-slice computed tomography angiography between January 1, 2017 and December 31, 2018 for suspected acute ischemic stroke within 24 hours of onset were retrospectively identified. The multimodal computed tomographies were assessed by 2 neuroradiologists in consensus for the presence of an intracranial anterior circulation LVO or M2-segment middle cerebral artery occlusion (the reference standard). The patients' computed tomography angiographies were then processed using an automated LVO-detection algorithm (RAPID CTA). Receiver-operating characteristic analysis was used to determine sensitivity, specificity, and negative predictive value of the algorithm for detection of (1) an LVO and (2) either an LVO or M2-segment middle cerebral artery occlusion. Results- CTAs from 477 patients were analyzed (271 men and 206 women; median age, 71; IQR, 60-80). Median processing time was 158 seconds (IQR, 150-167 seconds). Seventy-eight patients had an anterior circulation LVO, and 28 had an isolated M2-segment middle cerebral artery occlusion. The sensitivity, negative predictive value, and specificity were 0.94, 0.98, and 0.76, respectively for detection of an intracranial LVO and 0.92, 0.97, and 0.81, respectively for detection of either an intracranial LVO or M2-segment middle cerebral artery occlusion. Conclusions- The fully automated algorithm had very high sensitivity and negative predictive value for LVO detection with fast processing times, suggesting that it can be used in the emergent setting as a screening tool to alert radiologists and expedite formal diagnosis.

  View details for DOI 10.1161/STROKEAHA.119.026259

  View details for PubMedID 31495328

• CT Perfusion to Predict Response to Recanalization in Ischemic Stroke. Annals of neurology Lansberg, M. G., Christensen, S., Kemp, S., Mlynash, M., Mishra, N., Federau, C., Tsai, J. P., Kim, S., Nogueria, R. G., Jovin, T., Devlin, T. G., Akhtar, N., Yavagal, D. R., Haussen, D., Dehkharghani, S., Bammer, R., Straka, M., Zaharchuk, G., Marks, M. P., Albers, G. W. 2017

  Abstract

  To assess the utility of computed tomographic (CT) perfusion for selection of patients for endovascular therapy up to 18 hours after symptom onset.We conducted a multicenter cohort study of consecutive acute stroke patients scheduled to undergo endovascular therapy within 90 minutes after a baseline CT perfusion. Patients were classified as "target mismatch" if they had a small ischemic core and a large penumbra on their baseline CT perfusion. Reperfusion was defined as >50% reduction in critical hypoperfusion between the baseline CT perfusion and the 36-hour follow-up magnetic resonance imaging.Of the 201 patients enrolled, 190 patients with an adequate baseline CT perfusion study who underwent angiography were included (mean age = 66 years, median NIH Stroke Scale [NIHSS] = 16, median time from symptom onset to endovascular therapy = 5.2 hours). Rate of reperfusion was 89%. In patients with target mismatch (n = 131), reperfusion was associated with higher odds of favorable clinical response, defined as an improvement of ≥8 points on the NIHSS (83% vs 44%; p = 0.002, adjusted odds ratio [OR] = 6.6, 95% confidence interval [CI] = 2.1-20.9). This association did not differ between patients treated within 6 hours (OR = 6.4, 95% CI = 1.5-27.8) and those treated > 6 hours after symptom onset (OR = 13.7, 95% CI = 1.4-140).The robust association between endovascular reperfusion and good outcome among patients with the CT perfusion target mismatch profile treated up to 18 hours after symptom onset supports a randomized trial of endovascular therapy in this patient population. Ann Neurol 2017;81:849-856.

  View details for DOI 10.1002/ana.24953

  View details for PubMedID 28486789

• Associations Between CTP Ischemic Core Volume, ASPECTS Scores and Clinical Outcomes After Endovascular Reperfusion Marks, M. P., Christensen, S., Tsai, J. P., Mlynash, M., Kemp, S., Mishra, N., Federau, C., Kim, S., Haussen, D. C., Dehkharghani, S., Devlin, T. G., Yavagal, D. R., Akhtar, N., Jovin, T., Nogueira, R. G., Bammer, R., Straka, M., Zaharchuk, G., Albers, G. W., Lansberg, M. G. LIPPINCOTT WILLIAMS & WILKINS. 2016

  View details for Web of Science ID 000399956103167

• Severe CT Perfusion Bolus Delays Predict Infarct Growth Despite Reperfusion Christensen, S., Tsai, J., Kemp, S., Mishra, N., Kim, S., Mlynash, M., Federau, C., Bammer, R., Frankel, M., Dehkharghani, S., Devlin, T., Yavagal, D., Straka, M., Zaharchuk, G., Akhtar, N., Haussen, D., Marks, M., Jovin, T., Nogueira, R., Albers, G., Lansberg, M. LIPPINCOTT WILLIAMS & WILKINS. 2016

  View details for Web of Science ID 000399956102139

• Arterial Occlusive Lesion Location Does Not Impact Functional Outcome in Patients with Endovascular Reperfusion Kim, S., Christensen, S., Mlynash, M., Tsai, J. P., Federau, C., Kemp, S. M., Mishra, N., Frankel, M., Dehkharghani, S., Devlin, T. G., Yavagal, D. R., Akhtar, N., Tudor, J., Nogueira, R., Bammer, R., Straka, M., Zaharchuk, G., Albers, G. W., Marks, M., Lansberg, M. LIPPINCOTT WILLIAMS & WILKINS. 2016

  View details for Web of Science ID 000399956102122

• The Malignant CTP Imaging Profile Predicts Worse Functional Outcomes Mlynash, M., Christensen, S., Kemp, S. M., Mishra, N., Federau, C., Tsai, J. P., Kim, S., Frankel, M., Dehkharghani, S., Devlin, T. G., Yavagal, D. R., Akhtar, N., Jovin, T., Nogueira, R., Bammer, R., Straka, M., Zaharchuk, G., Albers, G. W., Marks, M. P., Lansberg, M. G., CRISP Investigators LIPPINCOTT WILLIAMS & WILKINS. 2016

  View details for Web of Science ID 000399956100155

• Main Results of the CTP to Predict Response to Recanalization in Ischemic Stroke Project (CRISP) Lansberg, M. G., Christensen, S., Kemp, S., Mlynash, M., Mishra, N., Federau, C., Tsai, J. P., Kim, S., Haussen, D. C., Dehkharghani, S., Devlin, T. G., Yavagal, D. R., Akhtar, N., Jovin, T., Nogueira, R. G., Bammer, R., Straka, M., Zaharchuk, G., Marks, M. P., Albers, G. W. LIPPINCOTT WILLIAMS & WILKINS. 2016

  View details for Web of Science ID 000399956100055

• Patient Selection is a Better Predictor of Good Outcome Than Time to Reperfusion in Acute Ischemic Stroke. Tsai, J. P., Mlynash, M., Christensen, S., Kemp, S., Mishra, N., Federau, C., Kim, S., Frankel, M., Dehkharghani, S., Devlin, T. G., Yavagal, D. R., Akhtar, N., Jovin, T., Nogueira, R. G., Bammer, R., Straka, M., Zaharchuk, G., Gregory, W., Marks, M. P., Lansberg, M. G. LIPPINCOTT WILLIAMS & WILKINS. 2016

  View details for Web of Science ID 000399956100005