Dr. Fukaya practices Vascular Medicine at the Stanford Vascular Clinics and Advanced Wound Care Center. She received her medical education in Tokyo and completed her medical training both in the US and Japan. She joined Stanford in 2015.
Vascular Medicine covers a wide range of vascular disorders including chronic venous insufficiency, varicose veins, deep vein thrombosis, post thrombotic syndrome, peripheral artery disease, carotid artery disease, cardiovascular risk evaluation, fibromuscular dysplasia, rare vascular disease, lymphedema, arterial/venous/diabetic ulcers, and wound care.
Dr. Fukaya has a special interest in venous disease and started the Stanford Vascular and Vein Clinic in 2016.
Board Certified in Vascular Medicine
Board Certified in Internal Medicine
Board Certified in Internal Medicine (Japan)
Board Certified in Plastic and Reconstructive Surgery (Japan)
- Vascular Medicine
- Venous Disease
- Varicose Veins
- Wound Healing
- Peripheral Artery Disease
- Deep Vein Thrombosis
- Fibromuscular Dysplasia
- Internal Medicine
MD, Tokyo Women's Medical University
PhD, Tokyo Women's Medical University
Fellowship, University of Pennsylvania, Vascular Medicine
Residency, Beth Israel Medical Center, Lankenau Medical Center, Internal Medicine
Residency, Tokyo Women's Medical University, Plastic and Reconstructive Surgery
An international, multicenter, randomized, double-blind, placebo-controlled phase 3 trial investigating the efficacy and safety of rivaroxaban to reduce the risk of major thrombotic vascular events in patients with symptomatic peripheral artery disease undergoing lower extremity revascularization procedures. Phase III, Sponsor: Bayer. Co-investigator
Genetics of Peripheral Vascular Disease
Study on the genetic underpinnings of peripheral vascular disease. GWAS meta-analysis. Principal Investigator.
Er:YAG Laser versus Sharp Debridement in Management of Chronic Wounds: Effects on Pain and Bacterial Load.
Wound repair and regeneration : official publication of the Wound Healing Society [and] the European Tissue Repair Society
Chronic wounds affect roughly 6.5 million patients in the United States annually. Current standard of therapy entails weekly sharp debridement. However, the sharp technique is associated with significant pain, while having minimal impact on the bioburden. Our study proposes the Er:YAG laser as an alternative method of debridement that may decrease procedural pain, reduce bioburden, and potentially improve overall healing. This pilot study was performed as a prospective, randomized, controlled, crossover clinical trial, containing two groups: 1) one group underwent single laser debridement session first, followed by single sharp debridement session one week later; 2) the other group underwent single sharp debridement session first, followed by single laser debridement session one week later. Variables analyzed included pain during debridement, pre- and post-debridement wound sizes, pre- and post-debridement bacterial loads and patient preference. Twenty-two patients were enrolled (12 patients in Group 1, plus 10 patients in Group 2). The mean pain score for patients undergoing laser debridement was 3.0 ±1.7 versus 4.8 ±2.6 for those undergoing sharp debridement (p=0.003). The mean percent change in wound size one-week post-laser debridement was -20.8% ±80.1%, as compared with -36.7% ±54.3% one-week post-sharp debridement (p=0.6). The percentage of patients who had a bacterial load in the Low/Negative category increased from 27.3% to 59.1% immediately after laser debridement (p=0.04), versus 54.5% to 68.2% immediately after sharp debridement (p=0.38). Moreover, there was a sustained decrease in bacterial load one-week post-laser debridement, as compared with no sustained decrease one-week post-sharp debridement (p <0.02). Overall, 52.9% of patients preferred laser debridement versus 35.3% for sharp debridement. We believe that Er:YAG laser serves as a promising technology in chronic wounds, functioning as a potentially superior alternative to sharp debridement, the current standard of therapy. This article is protected by copyright. All rights reserved.
View details for DOI 10.1111/wrr.12764
View details for PubMedID 31587431
- Clinical and Genetic Determinants of Varicose Veins Prospective, Community-Based Study of approximate to 500 000 Individuals CIRCULATION 2018; 138 (25): 2869–80
Clinical and Genetic Determinants of Varicose Veins.
2018; 138 (25): 2869–80
BACKGROUND: Varicose veins are a common problem with no approved medical therapies. Although it is believed that varicose vein pathogenesis is multifactorial, there is limited understanding of the genetic and environmental factors that contribute to their formation. Large-scale studies of risk factors for varicose veins may highlight important aspects of pathophysiology and identify groups at increased risk for disease.METHODS: We applied machine learning to agnostically search for risk factors of varicose veins in 493519 individuals in the UK Biobank. Predictors were further studied with univariable and multivariable Cox regression analyses (2441 incident events). A genome-wide association study of varicose veins was also performed among 337536 unrelated individuals (9577 cases) of white British descent, followed by expression quantitative loci and pathway analyses. Because height emerged as a new candidate risk factor, we performed mendelian randomization analyses to assess a potential causal role for height in varicose vein development.RESULTS: Machine learning confirmed several known (age, sex, obesity, pregnancy, history of deep vein thrombosis) and identified several new risk factors for varicose vein disease, including height. After adjustment for traditional risk factors in Cox regression, greater height remained independently associated with varicose veins (hazard ratio for upper versus lower quartile, 1.74; 95% CI, 1.51-2.01; P<0.0001). A genome-wide association study identified 30 new genome-wide significant loci, identifying pathways involved in vascular development and skeletal/limb biology. Mendelian randomization analysis provided evidence that increased height is causally related to varicose veins (inverse-variance weighted: odds ratio, 1.26; P=2.07*10-16).CONCLUSIONS: Using data from nearly a half-million individuals, we present a comprehensive genetic and epidemiological study of varicose veins. We identified novel clinical and genetic risk factors that provide pathophysiological insights and could help future improvements of treatment of varicose vein disease.
View details for PubMedID 30566020
- Disparities as Predictors of Non-Healing in Lower Extremity Wounds ELSEVIER SCIENCE INC. 2018: E248
Bioimpedance and New-Onset Heart Failure: A Longitudinal Study of >500 000 Individuals From the General Population
JOURNAL OF THE AMERICAN HEART ASSOCIATION
2018; 7 (13)
Heart failure constitutes a high burden on patients and society, but although lifetime risk is high, it is difficult to predict without costly or invasive testing. We aimed to establish new risk factors of heart failure, which potentially could enable early diagnosis and preemptive treatment.We applied machine learning in the UK Biobank in an agnostic search of risk factors for heart failure in 500 451 individuals, excluding individuals with prior heart failure. Novel factors were then subjected to several in-depth analyses, including multivariable Cox models of incident heart failure, and assessment of discrimination and calibration. Machine learning confirmed many known and putative risk factors for heart failure and identified several novel candidates. Mean reticulocyte volume appeared as one novel factor and leg bioimpedance another, the latter appearing as the most important new marker. Leg bioimpedance was lower in those who developed heart failure during an up to 9.8-year follow-up. When adjusting for known heart failure risk factors, leg bioimpedance was inversely related to heart failure (hazard ratio [95% confidence interval], 0.60 [0.48-0.73] and 0.75 [0.59-0.94], in age- and sex-adjusted and fully adjusted models, respectively, comparing the upper versus lower quartile). A model including leg bioimpedance, age, sex, and self-reported history of myocardial infarction showed good discrimination for future heart failure hospitalization (Concordance index [C-index]=0.82) and good calibration.Leg bioimpedance is inversely associated with heart failure incidence in the general population. A simple model of exclusively noninvasive measures, combining leg bioimpedance with history of myocardial infarction, age, and sex provides accurate predictive capacity.
View details for PubMedID 29959136
Clinical and genetic determinants of varicose veins: a prospective, community-based prospective study of similar to 500,000 individuals
SAGE PUBLICATIONS LTD. 2018: 300
View details for Web of Science ID 000433926000017
Incentivizing physical activity through activity monitoring interventions in PAD - a pilot study
SAGE PUBLICATIONS LTD. 2018: 313
View details for Web of Science ID 000433926000035
Impact of Pocket Ultrasound Use by Internal Medicine Housestaff in the Diagnosis of Dyspnea
JOURNAL OF HOSPITAL MEDICINE
2014; 9 (9): 594-597
Recent reports demonstrate high diagnostic accuracy of lung ultrasound for evaluation of dyspnea. We assessed the feasibility of training internal medicine residents in lung ultrasound with a pocket ultrasound device.We performed a prospective, observational trial of residents performing lung ultrasound with a pocket ultrasound. Training consisted of two 90-minute sessions of didactics and supervised bedside performance. Two residents received an additional 2 weeks of training. Residents recorded a clinical diagnosis based on admission data. Following lung ultrasound performance, an ultrasound diagnosis was recorded integrating clinical and sonographic findings. Using receiver operating curve analysis, the area under the curve was calculated for both clinical diagnosis and ultrasound diagnosis using attending physician's final discharge diagnosis as the gold standard.Five residents performed 69 exams. The AUC for ultrasound diagnosis was significantly higher than that for clinical diagnosis (0.87 vs 0.81, P < 0.01). AUCs increased using lung ultrasound for diagnoses as follows: chronic obstructive pulmonary disease (0.73-0.85, P = 0.06), acute pulmonary edema (0.85-0.89, P = 0.49), pneumonia (0.77-0.88, P = 0.01), and pleural effusions (0.76-0.96, P < 0.002).Lung ultrasound performed by residents with a pocket ultrasound improved the diagnostic accuracy of dyspnea. Two residents undergoing extended training showed a total increase in diagnostic accuracy.
View details for DOI 10.1002/jhm.2219
View details for Web of Science ID 000342679100008
View details for PubMedID 24891227
Peripheral arterial disease, prevalence and cumulative risk factor profile analysis
EUROPEAN JOURNAL OF PREVENTIVE CARDIOLOGY
2014; 21 (6): 704-711
The primary aim of the present study was to determine the cumulative effect of a set of peripheral artery disease (PAD) risk factors among age, gender and race/ethnicity groups in the United States.We examined data from a nationally representative sample of the US population (National Health and Nutrition Examination Survey [NHANES], 1999-2004). A total of 7058 subjects 40 years or older that completed the interview, medical examination and had ankle-brachial index (ABI) measurements were included in this study.The age- and sex-standardized prevalence of PAD was 4.6 % (standard error [SE] 0.3%).The highest prevalence of PAD was observed among elderly, non-Hispanic Blacks and women. In a multivariable age-, gender- and race/ethnicity-adjusted model hypertension, diabetes, chronic kidney disease, and smoking were retained as PAD risk factors (p ≤ 0.05 for each). The odds of PAD increased with each additional risk factor present from a non-significant 1.5-fold increase (O.R 1.5, 95% confidence interval [CI] 0.9-2.6) in the presence of one risk factor, to more than ten-fold (OR 10.2, 95% CI 6.4-16.3) in the presence of three or more risk factors. In stratified analysis, non-Hispanic Blacks (OR 14.7, 95% CI 2.1-104.1) and women (OR 18.6, 95% CI 7.1-48.7) were particularly sensitive to this cumulative effect.In a large nationally representative sample, an aggregate set of risk factors that included diabetes mellitus, chronic kidney disease, hypertension and smoking significantly increase the likelihood of prevalent PAD. A cumulative risk factor analysis highlights important susceptibility differences among different population groups and provides additional evidence to redefine screening strategies in PAD.
View details for DOI 10.1177/2047487312452968
View details for Web of Science ID 000337565600004
View details for PubMedID 22739687
View details for PubMedCentralID PMC4436703
- Endothelial progenitor cell mobilization following acute wound injury WOUND REPAIR AND REGENERATION 2013; 21 (6): 907-908
Approach to diagnosing lower extremity ulcers
2013; 26 (3): 181-186
Chronic leg ulcers (as differentiated from wound of the foot) are most often due to venous disease, arterial insufficiency (peripheral arterial disease), or a combination of both. Treatment modalities vary depending on the etiology of the ulcer, so it is important to make an appropriate diagnosis of the wound. Like for most medical illnesses, the determination of the etiology of these wounds is based on history, physical examination, and testing.
View details for DOI 10.1111/dth.12054
View details for Web of Science ID 000320034800001
View details for PubMedID 23742278
- Images in vascular medicine. Spontaneous celiac artery dissection. Vascular medicine 2013; 18 (1): 47-48
Heparin-induced thrombocytopenia: analysis of risk factors in medical inpatients
BRITISH JOURNAL OF HAEMATOLOGY
2011; 154 (3): 373-377
Heparin-induced thrombocytopenia (HIT) is an unpredictable reaction to heparin characterized by thrombocytopenia and increased risk of life-threatening venous and/or arterial thrombosis. Data are lacking regarding additional risk factors that may be associated with the development of HIT. This study aimed to identify the risk factors that may be associated with HIT in medical inpatients receiving heparin. Twenty five thousand six hundred and fifty-three patients admitted to the medicine service who received heparin product were reviewed retrospectively. The diagnosis of HIT was confirmed if the platelet count dropped >50% from baseline and there was a positive laboratory HIT assay. Fifty-five cases of in-hospital HIT were observed. Multivariate analysis identified the administration of full anticoagulation dose with unfractionated heparin or exposure to heparin products for more than 5 d with an increased risk of HIT. Moreover, patients who were on haemodialysis, carried a diagnosis of autoimmune disease, gout or heart failure were also at increased risk. The results suggest that when using heparin products in these patient cohorts, increased surveillance for HIT is necessary.
View details for DOI 10.1111/j.1365-2141.2011.08746.x
View details for Web of Science ID 000292648000011
View details for PubMedID 21615718
Imaging of the superficial inferior epigastric vascular anatomy and preoperative planning for the SIEA flap using MDCTA
JOURNAL OF PLASTIC RECONSTRUCTIVE AND AESTHETIC SURGERY
2011; 64 (1): 63-68
The superficial inferior epigastric artery (SIEA) flap consists of skin and subcutaneous fat with limited donor-site morbidity and has the potential to be very versatile - either as a thin flap without excessive fat tissue or as a voluminous flap for breast reconstruction. However, anatomical inter-individual variability often makes the choice of a free SIEA flap difficult. Imaging of small-calibre vessels is possible with the multi-detector-row computed tomography angiography (MDCTA) and to obtain the characteristics of the superficial inferior epigastric vascular anatomy, we investigated the superficial inferior epigastric system using MDCTA.We investigated 17 patients who had abdominal wall MDCTA in preparation for a free flap procedure using either the deep inferior epigastric perforator (DIEP), SIEA or the groin flap. The visibility and anatomical characteristics including the branching pattern, the diameter, course of travel and layers were noted.The SIEA was visible in 64.7% and, of these, 36.4% had a common trunk formation with the superficial circumflex iliac artery (SCIA), while 63.6% arose independently. The measured diameters were SIEA 1.6 ± 0.4mm, SCIA 1.4 ± 0.4mm, deep circumflex iliac artery (DCIA) 2.4 ± 0.4mm, DIEA 2.9 ± 0.4mm and superficial inferior epigastric vein (SIEV) 3.1 ± 0.5mm. The SIEA consistently coursed lateral to and deeper than the SIEV and also lateral to the DIEA.MDCTA provided detailed three-dimensional information of the superficial inferior epigastric vascular system including the course and size of the SIEA. The information on vascular anatomy obtained with the MDCTA is valuable in the preoperative planning of the free SIEA flap and should be performed routinely.
View details for DOI 10.1016/j.bjps.2010.03.012
View details for Web of Science ID 000285408300020
View details for PubMedID 20392682
Granular cell tumor of the suprasternal space
JOURNAL OF DERMATOLOGY
2010; 37 (10): 900-903
A case of granular cell tumor (GCT) was reported. We encountered a 33-year-old woman with a painless, elastic, hard mass in the soft tissue of the suprasternal space. The tumor was excised with several millimeters margin of normal tissue above the deep cervical fascia and the wound was closed primarily. Histological examination on hematoxylin-eosin stain showed a tumor growth in the mid- to deep dermis and eosinophilic small granules that were consistent with granular cell tumors. Immunohistochemical studies showed positive staining for S-100 protein. We experienced a case of a granular cell tumor occurring in the suprasternal space and report the importance of including it in the differential diagnosis of subcutaneous soft tissue tumors.
View details for DOI 10.1111/j.1346-8138.2010.00907.x
View details for Web of Science ID 000282177500007
View details for PubMedID 20860741
Magnetic resonance angiography to evaluate septocutaneous perforators in free fibula flap transfer
JOURNAL OF PLASTIC RECONSTRUCTIVE AND AESTHETIC SURGERY
2010; 63 (7): 1099-1104
In harvesting free fibula composite flaps, preoperative knowledge of the lower limb vascular anatomy is essential to prevent ischaemic complications or flap failure. Magnetic resonance angiography (MRA) allows imaging of the septocutaneous perforators (< or = 1-2mm diameter) of the peroneal artery used in the free fibula flap.We investigated seven patients undergoing the free fibula flap preoperatively with high-resolution MRA images to study the following: 1) tibio-peroneal anatomy, 2) peripheral artery disease, 3) the positions of the perforator vessels on the peroneal artery and their course in the posterolateral intermuscular septum and 4) the cutaneous distribution of the perforators, and to compare them to surgical findings.MRA demonstrated tibio-peroneal anatomy in sufficient detail to exclude anatomic variants and significant peripheral vascular disease, detected septocutaneous perforators arising from the peroneal artery coursing in the posterolateral intermuscular septum and determined the skin terminus of the septocutaneous perforators. All septocutaneous perforators found during surgery were detected prospectively on high-resolution MRA.Lower leg vascular anatomy assessment with high-resolution MRA determined the location of the septocutaneous perforators of the peroneal artery preoperatively with accuracy and precision. This anatomical knowledge provides for a safer procedure and the opportunity to plan surgical details preoperatively.
View details for DOI 10.1016/j.bjps.2009.06.002
View details for Web of Science ID 000278656200005
View details for PubMedID 19577973
Monitoring Partial and Full Venous Outflow Compromise in a Rabbit Skin Flap Model
PLASTIC AND RECONSTRUCTIVE SURGERY
2009; 124 (3): 796-803
Free flap failure often results from venous thrombosis. The authors developed a rabbit flap model of partial venous obstruction and evaluated four monitoring devices in detecting partial and full venous compromise.Nine skin flaps were elevated on their arteriovenous pedicles in rabbits. The flap was assessed with quantitative Doppler of arterial inflow, transcutaneous oxygen and carbon dioxide tension, near-infrared spectroscopy tissue oxygen saturation, and scanning laser Doppler imaging. After a stable baseline was achieved, the outflow vein was subjected to partial and full venous obstruction followed by release.Pedicle arterial flow decreased significantly from baseline (5.9 +/- 3.0 ml/minute) during partial (4.1 +/- 2.4 ml/minute; 30.5 percent; p < 0.01) and full obstruction (0.3 +/- 0.4 ml/minute; 94.9 percent; p < 0.01). All other measures changed significantly with full obstruction: transcutaneous oxygen tension decreased by 79.6 percent; transcutaneous carbon dioxide tension increased by 69.0 percent; near-infrared spectroscopy tissue oxygen saturation decreased by 35.7 percent; and scanning laser Doppler imaging decreased by 78.8 percent. Laser Doppler imaging was the only noninvasive device that decreased significantly (p < 0.01) with partial obstruction, from 222.8 +/- 77.3 units to 186.5 +/- 73.2 units (16.3 percent).The authors established a venous obstruction flap model and evaluated four clinically relevant monitoring devices during partial and full venous occlusion. All devices detected full occlusion, but only scanning laser Doppler imaging and arterial Doppler detected partial occlusion. Scanning laser Doppler imaging monitoring may allow warning of impending venous obstruction. Near-infrared spectroscopy tissue oxygen saturation varied the least between flaps and therefore may be the most easily interpreted device for full venous occlusion. Both characteristics are important for clinical application.
View details for DOI 10.1097/PRS.0b013e3181b03768
View details for Web of Science ID 000269485200013
View details for PubMedID 19730298
Monitoring the changes in intraparenchymatous venous pressure to ascertain flap viability
PLASTIC AND RECONSTRUCTIVE SURGERY
2007; 119 (7): 2111-2117
Disruption of venous outflow can lead to tissue necrosis. Thrombosis of a venous channel at the coaptation site in instances of free tissue transfer could cause death of the transplanted tissues. Although various techniques have been used to monitor the viability of transferred tissues, there has been no technique designed specifically to check the flow within and the patency of the venous channel. The authors have devised an approach with which to monitor the changes in venous pressure in a composite tissue transferred by means of microsurgical technique for bodily reconstruction.The status of the venous system in various composite tissue grafts was monitored at the time of surgery or for 3 days after the completion of surgery by placing a small-caliber catheter in the vein within the transferred tissue. A total of 52 patients participated in the study.The venous pressure noted in grafts with a patent venous channel remained constant within a range between 0 and 35 mmHg. Venous insufficiency was detected in three of the 52 cases, with unmistakable findings of an elevated venous pressure of over 50 mmHg.The technique of measuring the venous pressure by means of an indwelling venous catheter to monitor changes was found to accurately assess the patency of the venous channel and, by inference, the viability of the transferred tissue. No morbidity was associated with the technique.
View details for DOI 10.1097/01.prs.0000260594.94139.4a
View details for Web of Science ID 000246669000021
View details for PubMedID 17519709
Magnetic resonance angiography for free fibula flap transfer
JOURNAL OF RECONSTRUCTIVE MICROSURGERY
2007; 23 (4): 205-211
Recent refinements of magnetic resonance angiography (MRA) allow imaging vessels as small as the septocutaneous perforators (< or = 1 to 2 mm diameter), but a Medline review reveals no report of septocutaneous vessel imaging for free flap surgery. Challenges in fibula free flap preparation include knowledge of: (1) tibioperoneal anatomy, (2) the positions of the perforator vessels on the peroneal artery and their course in the posterolateral intermuscular septum, and (3) the cutaneous distribution of the perforators. Questioning whether high-resolution MRA could image these, we studied the lower extremities of nine healthy volunteers. MRA demonstrated tibioperoneal anatomy in sufficient detail to exclude anatomic variants and significant peripheral vascular disease and showed septocutaneous perforators arising from the peroneal artery and coursing in the posterolateral intermuscular septum to the skin. High-resolution MRA provided anatomic and clinical information that conventionally has been impossible to obtain preoperatively or has required multiple tests, often of an invasive nature.
View details for DOI 10.1055/s-2007-981501
View details for Web of Science ID 000247092000005
View details for PubMedID 17530612
HBO and gas embolism
2007; 29 (2): 142-145
Gas embolism, which occurs with the entry of gas into the circulatory system from the vein, artery or both, is a potentially serious even fatal condition. The two main causes of gas embolism are iatrogenic and diving. The site of entry and the signs and symptoms distinguish between arterial and venous embolism. The entering gas may be air, but may also be CO(2) or other gases, especially in iatrogenic embolism. Supportive care is the primary therapy for venous gas embolism, while hyperbaric oxygen therapy in addition to supportive care is the first line of treatment for arterial gas embolism. In this article, we will review the pathophysiology, etiology, diagnosis and treatment of gas embolism.
View details for DOI 10.1179/016164107X174165
View details for Web of Science ID 000246301000005
View details for PubMedID 17439698
- Divided naevus of the penis: A hypothesis on the embryological mechanism of its development ACTA DERMATO-VENEREOLOGICA 2003; 83 (2): 155-156