Faculty Bibliography

PURPOSE/OBJECTIVE: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/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.

Purpose: To assess the impact of muscle mass on survival in patients with hepatocellular carcinoma undergoing yttrium-90 radioembolization. Materials: The medical records of 186 patients undergoing Yttrium-90 radioembolization for hepatocellular carcinoma between April 2014 and May 2017 were retrospectively reviewed. Fifty patients with an abdominal MRI performed within 90 days prior to treatment were identified. All patients underwent standardized abdominal and liver MRI sequence protocols. Axial T2-weighted fat-suppressed sequences were used for image analysis. The paraspinal musculature was manually segmented at the level of the origin of the superior mesenteric artery using syngo.via (Siemens Healthineers, USA) and used to calculate skeletal muscle area (cm²) and skeletal muscle index (cm²/m²). Sarcopenia was defined as skeletal muscle area < 35.23 cm² for men and < 31.53 cm² for women. Medical records were reviewed to determine patient survival following treatment. Descriptive statistics, including Mann-Whitney tests and receiver operating characteristic curves, were performed.
Result(s): Fifty patients (86% male) with mean age 64 years (range, 31-83 years) met inclusion criteria. Death was reported for 49% (21/43) of male and 57% (4/7) of female patients, with average follow-up of 21 months (range, 0.7-56 months). Sarcopenia was identified in 16% (7/43) of male and 29% (2/7) of female patients. There were statistically significant differences in skeletal muscle area (48.72 +/- 12.01 cm² vs. 42.18 +/- 15.13 cm²) (P = 0.047) and skeletal muscle index (16.26 +/- 2.69 cm²/m² vs. 14.56 +/- 5.83 cm²/m²) (P = 0.024) between men who survived and died. Differences for the seven female patients included in the study did not achieve statistical significance, likely due to small sample size. Median survival was estimated as 1403 days for nonsarcopenic men (36/43) and 243 days for sarcopenic men (7/43) (P = 0.272).
Conclusion(s): Muscle mass on pre procedure MRI predicts survival in patients with hepatocellular carcinoma undergoing Yttrium-90 radioembolization. Sarcopenia may be associated with shorter survival and ongoing analysis of additional patients will improve study power to detect significant differences.
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Purpose: As interventional radiology (IR) transitions to a clinical model and reimbursement patterns change, quantifying revenue may help emphasize IR's value. This study sought to quantify the total and relative contributions of evaluation and management (E&M), diagnostic imaging, and procedural services to total revenue and work relative value units (wRVU) within an academic interventional oncology service line. Materials: This study included a retrospective review of 100 consecutive interventional oncology patients with an index procedure between July 1, 2017, and December 30, 2017. Patient charts were reviewed for the 3 months prior to the first procedure and 6 months beyond the final procedure to capture pre- and postprocedural revenue. Patient demographics and current procedural terminology (CPT) codes associated with each IR encounter were collected. The wRVU and total revenue based on the national payment amount were extracted from the 2019 Centers for Medicare and Medicaid Services (CMS) Physician Fee Schedule database.
Result(s): The 100 patients (66% male, mean age 65.6 years) underwent a total of 230 procedures, most often for treatment of hepatocellular carcinoma (71%). Procedures included radioembolization (39.1%), MAA mapping (32.6%), hepatic ablation (17.8%), TACE/bland embolization (9.1%), and renal ablation (1.3%). Of the 254 office visits generated, most were coded as level 3 (15.3%), 4 (44.9%), or 5 (39.0%). Mean office visit length was 37 min +/- 13 min. A total of 445 imaging studies were generated, including pre/postprocedural (260 MRI and 66 CT) and nuclear medicine (119) imaging. The service line generated a total of 5584 wRVU from procedures (4336, 77.6%), office visits (480, 8.6%), and imaging (767, 13.7%). Assuming CMS reimbursement, these wRVUs translated to a total of $388,665 from procedures ($225,463, 58.0%), imaging ($129,473, 33.3%), and office visits ($33,728, 8.7%). Individual patient wRVU 49.8 (25-75% IQR 30.8-72.0) and revenue $3457 ($2381-$4924) varied considerably.
Conclusion(s): In an academic interventional oncology service line, wRVU and revenue are generated primarily by procedural work. However, non-procedural work contributes a substantial portion (~40%) of the revenue.
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Purpose: To identify clinical, procedural, and logistical factors that influence time to inpatient interventional radiology (IR) procedures. Materials: All inpatient IR procedures performed at two tertiary care academic medical centers in January 2018 were retrospectively reviewed. Procedures were included if a complete consult note (with an associated time), and procedure start time were available. Time to procedure (TTP) was defined as the interval from consult note entry to procedure start time in hours. Clinical and procedure data which may influenced TTP were analyzed, including day of week, time of consult, procedure urgency and complexity, availability of imaging and laboratory values, requesting clinical service, patient vital signs, and procedural urgency. Consult time of day was divided into four time periods: early day (08:00-12:00), late day (12:00-16:00), evening (16:00-20:00), and overnight (20:00 - 08:00).
Result(s): A total of 127 inpatient procedures were performed on 116 patients (mean age, 59 years; 43% male). Procedures performed on Wednesdays and Fridays had the longest TTP (mean, 32 and 21 hours respectively, P = 0.010). Procedures performed during the weekend and on Mondays had the shortest TTP (mean, 2.9 and 10.8 hours, respectively, P = 0.010). The time of day the consult was completed correlated significantly with TTP (P = 0.038), with the shortest TTP for consults requested in the early day (mean, 11.4 hours) and overnight (mean, 11.5 hours) and the longest TTP for those requested in the afternoon (mean, 27.4 hours). Lack of appropriate imaging resulted in longer TTP (mean, 35 vs. 17 hours, P = 0.029). High urgency procedures had significantly shorter TTP (P = 0.038). There was no significant correlation between TTP and fasting status (P = 0.073), anticoagulation (P = 0.073), availability of appropriate labs (0.225), procedure category (P = 0.086), bed location (P = 0.094), and requesting service (P = 0.100).
Conclusion(s): Overnight, early day, and urgent procedures had the shortest TTP, whereas afternoon and later week consults had the longest TTP. Examining the underlying reasons for these trends may offer opportunities to reduce TTP for inpatient IR procedures.
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Purpose: We sought to quantify the total and relative contributions of evaluation and management (E&M), diagnostic imaging, and procedural services to total revenue and work relative value units (wRVU) within an academic interventional prostate artery embolization service line. Additionally, we evaluated the fluctuations in revenue dependent on hospital compared to office-based lab (OBL) procedural setting. Materials: We performed a retrospective review of all prostate artery embolization patients at a single institution with an index procedure between May 2018 and August 2019. Patient charts were reviewed to capture pre- and postprocedural revenue. Patient demographics and current procedural terminology (CPT) codes associated with each IR encounter were collected. The wRVU and total revenue were estimated using the national payment reported in the 2019 Center for Medicare and Medicaid (CMS) Physician Fee Schedule database.
Result(s): A total of 18 patients (all male, mean age 73.7 years) underwent a total of 20 prostate artery embolization, most often for treatment of lower urinary tract symptoms related to benign prostatic hypertrophy (94.4%). Of the 27 office visits generated, most were level 3 (10, 37.0%), 4 (12, 44.4%), or 5 (5, 18.5%). Mean office visit length was 36.1 min +/- 14.6 min. A total of 16 imaging studies were generated. The service line generated a total of 611.48 wRVU from procedures (529.49, 86.6%), office visits (51.71, 8.5%), and imaging (30.28, 5.0%). The total corresponding revenue was $116,622.53, of which $110,201.44 (94.5%) was from procedures, $2870.51 (2.5%) was from imaging, and $3550.57 (3.0%) was from office visits. Of the 20 procedures, 7 were performed in an OBL (35.0%) and 13 were performed in the hospital (65.0%). OBL procedures generated $93,013.31 (84.4%), while hospital procedures generated $17,188.13 (15.6%).
Conclusion(s): In an academic interventional prostate artery embolization service line, wRVU and revenue are driven primarily by procedural work. 13% of the RVUs and 6% of the revenue came from non-procedural work. Procedural revenue was higher in the OBL setting when compared to hospital procedures.
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Purpose: To describe our experience with lung cryoablation and factors impacting procedural outcomes. Materials: We performed a retrospective review of all percutaneous lung cryoablation patients done at a single institution between August 2017 and May 2019. Procedures were performed using computed tomographic guidance and triple freeze-thaw protocol. Complications and intraprocedural imaging features of the ice balls were recorded. Tumor progression was determined via World Health Organization guidelines. Overall survival was calculated using Kaplan-Meier analysis.
Result(s): A total of 39 patients (mean age, 75.1 years; range 40-94 years), 61.5% (25/39) of whom were female, underwent a total of 45 procedures. The mean follow-up time was 398.4 days (range, 34-746). The mean pre-ablation size of the lung cancer was 19.0 x 13.4 mm. 48.9% (22/45) of tumors were ground glass or part solid. An average of 1.3 probes (range, 1-3) were used for each case (1.4 probe per cm of tumor). 5 cases were performed with a round 2.1 cm diameter ice device, while 40 were performed with an ovoid 2.1 cm diameter device. The immediate post ablation zone measured an average of 28.0 x 21.2 mm (range, 9.4-62.5 mm). At 1-month follow-up, the ablation zone measured 29.3 x 19.3 mm (range, 14.3-47.0 mm). Pneumothorax was the most common complication seen in 46.7% (21/45) of cases. Chest tube placement was required in 33.3% (15/45) of cases. Local recurrence was seen in 6.7% (3/45) of lesions during the follow-up period. There were no 30-day mortalities; however, there were 6 deaths recorded (15.3%) during the study period. 83.3% (5/6) of the deaths were patients with solid tumors. Mean tumor size in these patients was 21.8 x 17.3 mm (range, 15.0-33.0 mm). Mean overall survival probability by Kaplan-Meier was 88.8% (SE: 0.05) at 1 year and 73.2% (SE: 1.4) at 2 years.
Conclusion(s): Lung cryoablation remains a safe and effective therapy option for patients with early stage malignant lung tumors, including both ground glass and part solid tumors. Current cryoablation technologies provide adequate ablation zones for tumors up to 2.0 cm.
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Purpose: To compare the efficacy of transjugular intrahepatic portosystemic shunt (TIPS) to anticoagulation and no treatment in cirrhotic patients with portal vein thrombosis (PVT). Materials: This single-center retrospective study evaluated 64 consecutive cirrhotic patients with imaging diagnosis of PVT between November 2005 and July 2019. 15 patients were excluded due to lack of adequate follow-up imaging. Of the remaining 49 patients, 11 (22%) were female. The median age was 61.5 (range, 24-80) years. 9 (18%) patients were treated with TIPS, 12 (24%) with anticoagulation, and 28 (57%) received no treatment. Demographic and clinical data were collected by reviewing the electronic medical record. PVT was evaluated using contrast-enhanced CT or MRI. Thrombus burden in the main portal (MPV), superior mesenteric (SMV), and splenic (SV) vein was graded as follows: grade 1, < 25%; grade 2, 26-50%; grade 3, 51-75%; and grade 4, > 75% of the luminal diameter. Yerdel scoring system was also used to evaluate the extent of portomesenteric thrombus. Thrombus burden at 6 and 12 months was compared to baseline imaging. Patient survival was estimated using Kaplan-Meier analysis. The extent of baseline thrombus was compared using Kruskal-Wallis test. Treatment response was analyzed by chi square test.
Result(s): There was no statistically significant difference in baseline thrombus burden between the 3 groups (MPV, P = 0.345; SMV, P = 0.244; SV, P = 0.541; Yerdel grade, P = 0.230). At 6 months, 87.5%, 58.3%, and 4.8% patients demonstrated complete or partial recanalization in the TIPS, anticoagulation, and no treatment groups respectively (TIPS/no treatment, P <0.0001; TIPS/anticoagulation, P = 0.163). At 12 months, 100%, 57.1%, 11.1% patients demonstrated complete or partial recanalization in the TIPS, anticoagulation, and no treatment groups respectively (TIPS/no treatment, P <0.0001; TIPS/ anticoagulation, P = 0.051). The overall survival between the 3 groups was not significantly different (P = 0.788) Conclusion(s): TIPS has significantly higher recanalization rate compared to no treatment and has a trend towards higher recanalization rate than that of anticoagulation at 6 and 12 months in cirrhotic patients with PVT.

PURPOSE/OBJECTIVE:To investigate the safety of yttrium-90 radioembolization in combination with checkpoint inhibitor immunotherapy for the treatment of hepatocellular carcinoma (HCC). MATERIALS AND METHODS/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.

PURPOSE/OBJECTIVE: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/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.

Familiarity with different instruments and understanding the basics of image guidance techniques are essential for interventional radiology trainees. However, there are no structured references in the literature, and trainees are left to "pick it up as they go". Puncture needles, guidewires, sheath systems, and catheters represent some of the most commonly used daily instruments by interventional radiologists. There is a large variety of instruments, and understanding the properties of each tool will allow trainees to better assess which type is needed for each specific procedure. Along with understanding the tools required to perform various interventional radiology procedures, it is important for trainees to learn how to organize the room, procedural table, and various equipment that is used during the procedure. Minimizing clutter and improving organization leads to improved efficiency and decreased errors. In addition, having a fundamental knowledge of fluoroscopy, the most commonly used imaging modality, is an integral part of beginning training in interventional radiology.