The Impact of Virtual Residency Interviews on the Geographic Distribution of Integrated Interventional and Diagnostic Radiology Residency Matches.

PURPOSE: To characterize how the adoption of virtual residency interviews (2020-2021 cycle) has impacted the geographic distribution of radiology resident matches. METHODS: University-based interventional (IR) and diagnostic radiology (DR) residency programs from 2017 to 2021 were identified using a national residency database (FRIEDA). Public applicant data were obtained from official residency program websites. Medical schools and residency programs were categorized by US census regions. Geographic applicant distribution before and after the initiation of virtual interviews was statistically assessed using Chi-square tests. The effect of virtual interviews on the probability of matching within the same geographic region as one's medical school was evaluated with multivariate logistic regression. RESULTS: 4358 radiology residents (88% diagnostic, 12% interventional) matched at 102 radiology programs during the study period. 71% (n = 3115 residents) had data available for analysis. 56.3% of DR and 49.3% of IR residents matched in the same geographic region as their medical school. The geographic distribution of applicants who matched at Southern IR residency programs significantly changed after implementation of virtual interviews (p < 0.0001). Virtual interviews did not increase the odds of matching in the same region as one's medical school for IR (OR 1.11, p = 0.08) or DR (OR 1.01, p = 0.58) applicants. Top-20 ranked DR programs had lower odds of in-region matches (OR 0.87, p < 0.001). CONCLUSION: With few exceptions, shifting to virtual residency interviews did not significantly affect the geographic distribution of IR or DR residency matches. Top-ranked DR programs match more regionally diverse applicants.

Genicular Artery Embolization: A Review of Essential Anatomic Considerations.

Genicular artery embolization is increasingly recognized as a safe and effective treatment option for symptomatic knee osteoarthritis and recurrent hemarthrosis after total knee arthroplasty. Genicular arteries are an essential contributor to vascular supply for the knee joint and demonstrate considerable variability. Familiarity with the anatomy and common variations is critical for preprocedural planning, accurate target selection, and minimizing adverse events in transarterial embolization procedures. This review aimed to provide a detailed discussion of the genicular artery anatomy that is relevant to interventional radiologists performing genicular artery embolization.

Genicular Artery Embolization for Treatment of Knee Osteoarthritis: Interim Analysis of a Prospective Pilot Trial Including Effect on Serum Osteoarthritis-Associated Biomarkers.

PURPOSE: To characterize the safety, efficacy, and potential role of genicular artery embolization (GAE) as a disease-modifying treatment for symptomatic knee osteoarthritis (OA). MATERIALS AND METHODS: This is an interim analysis of a prospective, single-arm clinical trial of patients with symptomatic knee OA who failed conservative therapy for greater than 3 months. Sixteen patients who underwent GAE using 250-µm microspheres and had at least 1 month of follow-up were included. Six patients completed the 12-month follow-up, and 10 patients remain enrolled. Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) was evaluated at baseline and at 1, 3, and 12 months. Serum and plasma samples were collected for biomarker analysis. The primary end point was the percentage of patients who achieved the minimal clinically important difference (MCID) for WOMAC pain score at 12 months. Baseline and follow-up outcomes were analyzed using the Wilcoxon matched-pairs signed-rank test. RESULTS: Technical success of the procedure was 100%, with no major adverse events. The MCID was achieved in 5 of the 6 (83%) patients at 12 months. The mean WOMAC pain score decreased from 8.6 ± 2.7 at baseline to 4.9 ± 2.7 (P = .001), 4.4 ± 2.8 (P < .001), and 4.7 ± 2.7 (P = .094) at 1, 3, and 12 months, respectively. There was a statistically significant decrease in nerve growth factor (NGF) levels at 12 months. The remaining 8 biomarkers showed no significant change at 12 months. CONCLUSIONS: GAE is a safe and efficacious treatment for symptomatic knee OA. Decreased NGF levels after GAE may contribute to pain reduction and slowing of cartilage degeneration.

Pulmonary Cryoablation Outcomes in Octogenarians and Nonagenarians with Primary Lung Cancer.

PURPOSE: To characterize the effectiveness, safety, and length of stay (LOS) associated with pulmonary cryoablation for management of primary lung malignancies in patients aged ≥80 years. MATERIALS AND METHODS: A retrospective single-center database was compiled of all consecutive patients aged ≥80 years who underwent percutaneous computed tomography-guided cryoablation using modified triple-freeze protocol (1-3 ablation probes) for Stage IA-IIB primary lung malignancies between March 2017 and March 2020 (n = 19; 53% women; mean age, 85 years ± 3.5; range, 80-94 years). Follow-up imaging was assessed for local recurrence. Adverse events and LOS were recorded from chart review. Kaplan-Meier analysis was performed to assess both overall and local recurrence-free survival. RESULTS: Mean patient follow-up period was 21.6 months ± 10.8, and mean imaging follow-up period was 19.2 months ± 9.6. Overall survival at 3 years was 94% (95% CI, 81%-100%). Local recurrence-free survival was 100% throughout the imaging follow-up period. Intraprocedural pneumothorax occurred in 37% (7 of 19) of patients; pneumothorax risk was significantly associated with increased tumor distance from pleura (odds ratio, 1.2; P = .018). Sixty-three percent (12 of 19) of patients were discharged on the day of the procedure, with a mean LOS of 7.7 hours ± 1.6, whereas 37% of patients required overnight observation (2 of 19) or admission (5 of 19), with a mean LOS of 48.1 hours ± 19.4. Overall LOS for all patients was 22.6 hours ± 22.9. CONCLUSIONS: Percutaneous cryoablation of primary pulmonary malignancies can be performed in select octogenarians and nonagenarians with high 3-year overall and recurrence-free survival. Despite nonnegligible risk of pneumothorax, most patients are discharged on the day of the procedure.

Genicular artery embolization for treatment of knee osteoarthritis pain: Systematic review and meta-analysis.

Objective: Genicular artery embolization (GAE) is a novel, minimally invasive procedure for treatment of knee osteoarthritis (OA). This meta-analysis investigated the safety and effectiveness of this procedure. Design: Outcomes of this systematic review with meta-analysis were technical success, knee pain visual analog scale (VAS; 0-100 scale), WOMAC Total Score (0-100 scale), retreatment rate, and adverse events. Continuous outcomes were calculated as the weighted mean difference (WMD) versus baseline. Minimal clinically important difference (MCID) and substantial clinical benefit (SCB) rates were estimated in Monte Carlo simulations. Rates of total knee replacement and repeat GAE were calculated using life-table methods. Results: In 10 groups (9 studies; 270 patients; 339 knees), GAE technical success was 99.7%. Over 12 months, the WMD ranged from -34 to -39 at each follow-up for VAS score and -28 to -34 for WOMAC Total score (all p â€‹< â€‹0.001). At 12 months, 78% met the MCID for VAS score; 92% met the MCID for WOMAC Total score, and 78% met the SCB for WOMAC Total score. Higher baseline knee pain severity was associated with greater improvements in knee pain. Over 2 years, 5.2% of patients underwent total knee replacement and 8.3% received repeat GAE. Adverse events were minor, with transient skin discoloration as the most common (11.6%). Conclusions: Limited evidence suggests that GAE is a safe procedure that confers improvement in knee OA symptoms at established MCID thresholds. Patients with greater knee pain severity may be more responsive to GAE.

Predictors of need for endovascular intervention in hepatic trauma.

PURPOSE: Non-operative management of hepatic trauma with adjunctive hepatic arterial embolization (HAE) is widely accepted. Despite careful patient selection utilizing CTA, a substantial proportion of angiograms are negative for arterial injury and no HAE is performed. This study aims to determine which CT imaging findings and clinical factors are associated with the presence of active extravasation on subsequent angiography in patients with hepatic trauma. MATERIALS AND METHODS: The charts of 243 adults who presented with abdominal trauma and underwent abdominal CTA followed by conventional angiography were retrospectively reviewed. Of these patients, 49 had hepatic injuries on CTA. Hepatic injuries were graded using the American association for the surgery of trauma (AAST) CT classification, and CT images were assessed for active contrast extravasation, arterial pseudoaneurysm, sentinel clot, hemoperitoneum, laceration in-volving more than 2 segments, and laceration involving specific anatomic landmarks (porta hepatis, hepatic veins, and gallbladder fossa). Medical records were reviewed for pre- and post-angiography blood pressures, hemoglobin levels, and transfusion requirements. Angiographic images and reports were reviewed for hepatic arterial injury and performance of HAE. RESULTS: In multivariate analysis, AAST hepatic injury grade was significantly associated with increased odds of HAE (Odds ratio: 2.5, 95% CI 1.1, 7.1, p = 0.049). Univariate analyses demonstrated no significant association between CT liver injury grade, CT characteristics of liver injury, or pre-angiographic clinical data with need for HAE. CONCLUSION: In patients with hepatic trauma, prediction of need for HAE based on CT findings alone is challenging; such patients require consideration of both clinical factors and imaging findings.

Venous Malformations.

Venous malformations, the most common type of vascular malformation, are slow-flow lesions resulting from disorganized angiogenesis. The International Society for the Study of Vascular Anomalies (ISSVA) classification offers a categorization scheme for venous malformations based on their genetic landscapes and association with congenital overgrowth syndromes. Venous malformations present as congenital lesions and can have broad physiologic and psychosocial sequelae depending on their size, location, growth trajectory, and tissue involvement. Diagnostic evaluation is centered around clinical examination, imaging evaluation with ultrasound and time-resolved magnetic resonance imaging, and genetic testing for more complex malformations. Interventional radiology has emerged as first-line management of venous malformations through endovascular treatment with embolization, while surgery and targeted molecular therapies offer additional therapeutic options. In this review, an updated overview of the genetics and clinical presentation of venous malformations in conjunction with key aspects of diagnostic imaging and treatment are discussed.

Computed Tomography Evaluation of In Vivo Pulmonary Cryoablation Zone Sizes.

PURPOSE: To evaluate ablation zone sizes in patients undergoing pulmonary tumor cryoablation with 14-gauge cryoablation probes. MATERIALS AND METHODS: A single-center retrospective analysis of all consecutive patients who underwent cryoablation of pulmonary tumors with 1 or more 14-gauge probes (August 2017 to June 2020) was performed. Intraprocedural and 1-2-month postprocedural chest computed tomography (CT) scans were evaluated to characterize pulmonary lesions, ice balls, and ablation zones. Single-probe 14-gauge ablation zone volumes were compared with manufacturer reference isotherms and single- and 2-probe ablation zones from a prior investigation of 17-gauge probes. Overall survival and local recurrence-free survival were calculated to 3 years. RESULTS: Forty-seven pulmonary malignancies in 42 patients (women, 50%; mean age, 75.2 years ± 11.5) underwent cryoablation with 1 (n = 35), 2 (n = 10), or 3 (n = 2) cryoablation probes. One- to 2-month follow-up CT images were available for 30 of the 42 patients. The mean cryoablation zone volumes at 1-2 months when 1 (n = 21), 2 (n = 8), and 3 (n = 1) probes were used were 5.0 cm3 ± 2.3, 37.5 cm3 ± 20.5, and 28.4 cm3, respectively. The mean single-probe follow-up ablation zone volume was larger than that previously reported for 17-gauge probes (3.0 cm3 ± 0.3) (P < .001) but smaller than manufacturer-reported isotherms (11.6 cm3 for -40 °C isotherm) and the 2-probe ablation zone volume with 17-gauge devices (12.9 cm3 ± 2.4) (for all, P < 001). The 3-year overall survival and local recurrence-free survival were 69% (95% confidence interval [CI], 53%-89%) and 87% (95% CI, 74%-100%), respectively. CONCLUSIONS: Fourteen-gauge probes generate larger ablation volumes than those generated by 17-gauge probes. Manufacturer-reported isotherms are significantly larger than actual cryoablation zones. Cryoablation can attain low rates of local recurrence.

Comparison of Non-Tumoral Portal Vein Thrombosis Management in Cirrhotic Patients: TIPS Versus Anticoagulation Versus No Treatment.

BACKGROUND: There is a lack of consensus in optimal management of portal vein thrombosis (PVT) in patients with cirrhosis. The purpose of this study is to compare the safety and thrombosis burden change for cirrhotic patients with non-tumoral PVT managed by transjugular intrahepatic portosystemic shunt (TIPS) only, anticoagulation only, or no treatment. METHODS: This single-center retrospective study evaluated 52 patients with cirrhosis and non-tumoral PVT managed by TIPS only (14), anticoagulation only (11), or no treatment (27). The demographic, clinical, and imaging data for patients were collected. The portomesenteric thrombosis burden and liver function tests at early follow-up (6-9 months) and late follow-up (9-16 months) were compared to the baseline. Adverse events including bleeding and encephalopathy were recorded. RESULTS: The overall portomesenteric thrombosis burden improved in eight (72%) TIPS patients, three (27%) anticoagulated patients, and two (10%) untreated patients at early follow-up (p = 0.001) and in seven (78%) TIPS patients, two (29%) anticoagulated patients, and three (17%) untreated patients in late follow-up (p = 0.007). No bleeding complications attributable to anticoagulation were observed. CONCLUSION: TIPS decreased portomesenteric thrombus burden compared to anticoagulation or no treatment for cirrhotic patients with PVT. Both TIPS and anticoagulation were safe therapies.

MRI-Derived Sarcopenia Associated with Increased Mortality Following Yttrium-90 Radioembolization of Hepatocellular Carcinoma.

PURPOSE: To evaluate the influence of sarcopenia on survival in patients with hepatocellular carcinoma (HCC) treated with 90Y radioembolization. MATERIALS AND METHODS: This single-center retrospective cohort study analyzed 82 consecutive patients (65 men and 17 women, mean age 65 years, range 31-83 years) with HCC treated with 90Y radioembolization between December 2013 and December 2017. Sarcopenia was assessed on pre-procedure MRI performed within 100 days prior to 90Y radioembolization by segmenting the paraspinal musculature at the level of the superior mesenteric artery origin and subtracting fat-intensity pixels to yield fat-free muscle area (FFMA). Sarcopenia was defined as FFMA ≤31.97 cm2 for men and ≤28.95 cm2 for women. Survival at 90 days, 180 days, 1 year, and 3 years following initial treatment was assessed using medical and public obituary records. RESULTS: Sarcopenia was identified in 30% (25/82) of patients. Death was reported for 49% (32/65) of males and 71% (8/17) of females (mean follow-up 19.6 months, range 21 days-58 months). Patients with sarcopenia were found to have increased mortality at 180 days (31.8% vs. 8.9%) and 1 year (68.2% vs. 21.2%). Sarcopenia was an independent predictor of mortality adjusted for BCLC stage and sub-analysis demonstrated that sarcopenia independently predicted increased mortality for patients with BCLC stage B disease. CONCLUSION: Sarcopenia was associated with increased 180-day and 1-year mortality in HCC patients undergoing 90Y radioembolization. Sarcopenia was an independent predictor of survival adjusted for BCLC stage with significant deviation in the survival curves of BCLC stage B patients with and without sarcopenia.

Essentials of Insulinoma Localization with Selective Arterial Calcium Stimulation and Hepatic Venous Sampling.

Insulinomas are the most common functional pancreatic neuroendocrine tumor. Most insulinomas can be localized non-invasively with cross-sectional and nuclear imaging. Selective arterial calcium stimulation and hepatic venous sampling is an effective and safe minimally-invasive procedure for insulinoma localization that may be utilized when non-invasive techniques are inconclusive. The procedure's technical success and proper interpretation of its results is dependent on the interventional radiologist's knowledge of normal and variant pancreatic arterial perfusion. Accurate pre-operative localization aids in successful surgical resection. Technical and anatomic considerations of insulinoma localization with selective arterial calcium stimulation and hepatic venous sampling are reviewed.

Safety and Effectiveness of Yttrium-90 Radioembolization around the Time of Immune Checkpoint Inhibitors for Unresectable Hepatic Metastases.

PURPOSE: To assess the safety and effectiveness of yttrium-90 radioembolization and checkpoint inhibitor immunotherapy within a short interval for the treatment of unresectable hepatic metastases. MATERIALS AND METHODS: This single-institution retrospective study included 22 patients (12 men; median age, 65 y ± 11) with unresectable hepatic metastases and preserved functional status (Eastern Cooperative Oncology Group performance status 0/1) who received immunotherapy and radioembolization within a 15-month period (median, 63.5 d; interquartile range, 19.7-178.2 d) from February 2013 to March 2018. Primary malignancies were uveal melanoma (12 of 22; 54.5%), soft tissue sarcoma (3; 13.6%), cutaneous melanoma (3; 14%), and others (4; 18.2%). Studies were reviewed to March 2019 to assess Common Terminology Criteria for Adverse Events grade 3/4 toxicities, disease progression, and death. RESULTS: There were no grade 4 toxicities within 6 mo of radioembolization. Grade 3 hepatobiliary toxicities occurred in 3 patients (13.6%) within 6 months, 2 from rapid disease progression and 1 from a biliary stricture. Two patients (9.1%) experienced clinical toxicities, including grade 4 colitis at 6 months and hepatic abscess at 3 months. Median overall survival (OS) from first radioembolization was 20 mo (95% confidence interval [CI], 12.5-27.5 mo), and median OS from first immunotherapy was 23 months (95% CI, 15.9-30.1 mo). Within the uveal melanoma subgroup, the median OS from first radioembolization was 17.0 months (95% CI, 14.2-19.8 mo). Median time to progression was 7.8 months (95% CI, 3.3-12.2 mo), and median progression-free survival was 7.8 mo (95% CI, 3.1-12.4 mo). CONCLUSIONS: Checkpoint immunotherapy around the time of radioembolization is safe, with a low incidence of toxicity independent of primary malignancy.

Comparative Analysis of Safety and Efficacy of Transarterial Chemoembolization for the Treatment of Hepatocellular Carcinoma in Patients with and without Pre-Existing Transjugular Intrahepatic Portosystemic Shunts.

PURPOSE: To compare the safety and efficacy of transarterial chemoembolization for hepatocellular carcinoma (HCC) in patients with and without transjugular intrahepatic portosystemic shunts (TIPS). MATERIALS AND METHODS: This single-institution study included a retrospective review of 50 patients who underwent transarterial chemoembolization for HCC between January 2010 and April 2017. Twenty-five patients had preexisting TIPS, and 25 patients were selected to control for age, sex, and target tumor size. Baseline median Model for End-Stage Liver Disease (MELD; 13 TIPS, 9 control; P < .001) and albumin-bilirubin (ALBI; 3 TIPS, 2 control; P < .001) differed between groups. Safety was assessed on the basis of Common Terminology Criteria for Adverse Events (CTCAE) and change in MELD and ALBI grade assessed between 3 and 6 months. Efficacy was assessed by tumor response and time to progression (TTP). RESULTS: There was 1 severe adverse event (CTCAE grade >2) in the TIPS group. There was no difference in the change in MELD or ALBI grade. Although there was no difference in tumor response (P = .19), more patients achieved a complete response in the control group (19/25, 76%) than in the TIPS group (13/25, 52%). There was no difference in TTP (P = .82). At 1 year, 2 patients in the control group and 3 patients in the TIPS group received a liver transplant. Seven patients died in the TIPS group. CONCLUSIONS: Transarterial chemoembolization is as safe and effective in patients with TIPS as in patients without TIPS, despite worse baseline liver function. Severe adverse events are rare and may be transient.

Safety of Combined Yttrium-90 Radioembolization and Immune Checkpoint Inhibitor Immunotherapy for Hepatocellular Carcinoma.

PURPOSE: To investigate the safety of yttrium-90 radioembolization in combination with checkpoint inhibitor immunotherapy for the treatment of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: This single-center retrospective study included 26 consecutive patients with HCC who received checkpoint inhibitor immunotherapy within 90 days of radioembolization from April 2015 to May 2018. Patients had preserved liver function (Child-Pugh scores A-B7) and either advanced HCC due to macrovascular invasion or limited extrahepatic disease (21 patients) or aggressive intermediate stage HCC that resulted in earlier incorporation of systemic immunotherapy (5 patients). Clinical documentation, laboratory results, and imaging results at 1- and 3-month follow-up intervals were reviewed to assess treatment-related adverse events and treatment responses. RESULTS: The median follow-up period after radioembolization was 7.8 months (95% confidence interval [CI], 5.6-11.8). There were no early (30-day) mortality or grades 3/4 hepatobiliary or immunotherapy-related toxicities. Delayed grades 3/4 hepatobiliary toxicities (1-3 months) occurred in 2 patients in the setting of HCC disease progression. One patient developed pneumonitis. The median overall survival from first immunotherapy was 17.2 months (95% CI, 10.9-23.4). The median overall survival from first radioembolization was 16.5 months (95% CI, 6.6-26.4). From first radioembolization, time to tumor progression was 5.7 months (95% CI, 4.2-7.2), and progression-free survival was 5.7 months (95% CI, 4.3-7.1). CONCLUSIONS: Radioembolization combined with checkpoint inhibitor immunotherapy in cases of HCC appears to be safe and causes limited treatment-related toxicity. Future prospective studies are needed to identify the optimal combination treatment protocols and evaluate the efficacy of combination therapy.

A Descriptive Revenue Analysis of a Wound-Center IR Collaboration to Treat Lower Extremity Venous Ulcers.

PURPOSE: To describe the revenue from a collaboration between a dedicated wound care center and an interventional radiology (IR) practice for venous leg ulcer (VLU) management at a tertiary care center. MATERIALS AND METHODS: This retrospective study included 36 patients with VLU referred from a wound care center to an IR division during the 10-month active study period (April 2017 to January 2018) with a 6-month surveillance period (January 2018 to June 2018). A total of 15 patients underwent endovascular therapy (intervention group), whereas 21 patients did not (nonintervention group). Work relative value units (wRVUs) and dollar revenue were calculated using the Centers for Medicare and Medicaid Services Physician Fee Schedule. RESULTS: Three sources of revenue were identified: evaluation and management (E&M), diagnostic imaging, and procedures. The pathway generated 518.15 wRVUs, translating to $37,522. Procedures contributed the most revenue (342.27 wRVUs, $18,042), followed by E&M (124.23 wRVUs, $8,881), and diagnostic imaging (51.65 wRVUs, $10,599). Intervention patients accounted for 86.7% of wRVUs (449.48) and 80.0% of the revenue ($30,010). An average of 33 minutes (38.3 hours total) and 2.06 hours (36.8 hours total) were spent on E&M visits and procedures, respectively. CONCLUSIONS: In this collaboration between the wound center and IR undertaken to treat VLU, IR and E&M visits generated revenue and enabled procedural and downstream imaging revenue.