Role of Antiplatelet Therapy in Hemodialysis Arteriovenous Graft Secondary Patency Following Successful Percutaneous Thrombectomy.

PURPOSE: The purpose of this study was to elicit the relationship of antiplatelet therapy (AP) in maintaining arteriovenous graft (AVG) patency after successful percutaneous pharmacomechanical thrombectomy ("declot"). MATERIALS AND METHODS: This was an institutional review board-approved retrospective review of AVG declot procedures between July 2019 and August 2020. AVG characteristics, bleeding complications, anticoagulation and antiplatelet medication regimens, and thrombosis free survival were evaluated. Recurrent time-to-event analysis was performed using a Prentice-Williams-Peterson Gap time model was performed to evaluate AVG thrombosis free survival. RESULTS: A total of 109 declots were technically successful and performed in 63 individual patients. The majority of procedures were performed in upper arm grafts (71%, n = 45). Dual antiplatelet (DAPT) was prescribed after 52 declots (48%), single antiplatelet was prescribed after 36 declots (33%), and anticoagulation was prescribed after 31 declots (28%). Median thrombosis free survival was 37 days (range 1-412 days) in the no antiplatelet group, 84 days (range 1-427 days) in the single antiplatelet group, and 93 days (range 3-407 days) in the DAPT group. Anti-platelet medications trended towards protective of AVG thrombosis in multivariate analysis (hazard ratio 0.84, 95% confidence interval 0.60-1.19); however, this did not reach statistical significance (P = 0.33). A total of 4 major and 5 minor bleeding events occurred. CONCLUSION: The results of this study support further evaluation of AP therapy in preventing secondary rethrombosis of dialysis AVG.

Quantitative correlation of lumbar foraminal stenosis with local morphological metrics.

PURPOSE: Clinical evaluation of lumbar foraminal stenosis typically includes qualitative assessments of perineural epidural fat content around the spinal nerve root and evaluation of nerve root impingement. The present study investigates the use of several morphological MRI-derived metrics as quantitative predictors of foraminal stenosis grade. METHODS: 62 adult patients that underwent lumbar spine MRI evaluation over a 1-month duration in 2018 were included in the analysis. Radiological gradings of stenosis were captured from the existing clinical electronic medical record. Clinical gradings were recorded using a 0-5 scale: 0 = no stenosis, 1 = mild stenosis, 2 = mild-moderate stenosis, 3 = moderate stenosis, 4 = moderate-severe stenosis, 5 = severe stenosis. Quantitative measures of perineural epidural fat volume, nerve root cross-sectional area, and lumbar pedicle length were derived from T1 weighted sagittal spine MRI on each side of all lumbar levels. Spearman correlations of each measured metric at each level were then computed against the stenosis gradings. RESULTS: A total of 347 volumetric segmentation and radiological foraminal stenosis grade sets were derived from the 62-subject study cohort. Statistical analysis revealed significant correlations (p < 0.001) between the volume of perineural fat and stenosis grades for all lumbar vertebral levels. CONCLUSION: The results of the study have demonstrated that segmented volumes of perineural fat predict the severity of clinically scored foraminal stenosis. This finding motivates further development of automated perineural fat segmentation methods, which could offer a quantitative imaging biometric that yields more reproducible diagnosis, assessment, and tracking of foraminal stenosis.

A Cross-Sectional Analysis of Factors Associated with Appointment Completion and Visit Modality during Virtual Urology Visits.

INTRODUCTION: The necessary transition to telehealth during COVID-19 generated new challenges for providers and patients, with the opportunity to exacerbate or mitigate standing care inequities. To better understand virtual medicine care delivery in urology, we sought to identify factors associated with appointment completion and use of telephone or video visits. METHODS: We performed a retrospective, single-institutional cross-sectional analysis of all remote patient appointments from March 17, 2020-August 31, 2020. The primary outcome was appointment completion rate. Patients were determined to have not completed an appointment if they canceled, left before being seen or were a "no show." Secondary analysis evaluated factors associated with scheduling video vs telephone appointment. Various patient and appointment-specific factors were analyzed. Chi-squared tests and univariate logistic regression were used for analysis accordingly. RESULTS: Of 3,769 appointments, 2,996 (79.5%) were completed while 773 (20.5%) were not, with 1,544 (41.0%) completed over telephone while 2,225 (59.0%) used video. Race, age, income, insurance, location, division and appointment length showed statistical significance (p <0.05) for appointment completion and visit modality. Females were more likely to use video (62.7% vs 58.0%, p=0.01). Patients were more likely to complete afternoon visits (81.1% vs 78.3%, p=0.04), visits with physicians (81.2% vs 75.4%, p <0.01) and phone calls (83.3% vs 76.9%, p <0.01). CONCLUSIONS: Multiple factors were associated with both appointment completion rate and use of telephone or video. These factors may reflect disparities in social determinants of health and select patients may benefit from additional coordination of care to prevent missed appointments and deconstruct inequities.