Faculty Bibliography

Renal vein thrombosis is the most common non-catheter-associated venous thromboembolism event in neonates, accounting for up to 20% of cases. Although mortality rates are lower than a variety of other forms of pediatric thrombosis, renal vein thrombi are associated with significant short-term and long-term sequelae. This report presents the case of a full-term neonate presenting with bilateral renal vein thrombosis with inferior vena cava involvement treated with catheter-directed thrombolysis. This case report intends to highlight the value of a multidisciplinary approach to pediatric venous thromboembolism and to outline relevant procedural details and current laboratory and imaging monitoring of catheter-directed thrombolysis.

PURPOSE/OBJECTIVE:To evaluate the feasibility and benefits of performing yttrium-90 radioembolization in an office-based lab (OBL) compared to a hospital setting. MATERIALS AND METHODS/METHODS:A radioembolization program was established in March 2019 in an OBL that is managed by the radiology department of a tertiary care center. Mapping and treatment angiograms performed in the OBL from March 2019 through January 2020 were compared to mapping and treatment angiograms performed in the hospital during the same time period. RESULTS:One hundred seventy-six mapping and treatment angiograms were evaluated. There was no difference in the proportion of mapping versus treatment angiograms performed at each site, the proportion of lobar versus selective dose vial administrations, or the mean number of dose vials administered per treatment procedure. Procedure start delays were longer in the hospital than in the OBL (28.6 minutes vs 0.8 minutes; P < .0001), particularly for procedures that were not scheduled as the first case of the day (hospital later case delay, 38.8 minutes vs OBL later case delay, 0.5 minutes; P < .0001). Procedures performed in the hospital took longer on average than procedures performed in the OBL (2 hours, 1.8 minutes vs 1 hour, 44.4 minutes; P = .0004), particularly for procedures that were not scheduled as the first case of the day (hospital later case duration, 2 hours, 7.4 minutes vs OBL later case duration, 1 hour, 43 minutes; P = .0006). CONCLUSIONS:Establishing a radioembolization program within an OBL is feasible and might provide more efficient procedure scheduling than the hospital setting.

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 evaluate the effect of active inpatient and outpatient interventional radiology (IR) drainage catheter management on drain dwell time and percentage of drains removed by IR. Materials: Retrospective review was performed of drains placed by IR at a tertiary medical center. Exclusion criteria were no documentation of removal, dwell time less than 1 day, and pediatric, seroma, urinoma, or enteric fistula drains. Data collected for the 283 eligible drains included dwell time, IR versus referrer removal, and IR documentation. Statistical analysis was used to compare IR drain management across three phases: passive (January - June 2016), active inpatient/passive outpatient (July 2016 - February 2017) and active all patients (March 2017 - June 2019). Management was still considered passive after June 2016 if drains were lost to IR follow-up or referrer removed without IR involvement.
Result(s): Active inpatient drain management during phase 2 led to a significant 5.6 day decrease in drain dwell time compared to passive management (mean, 12.8 vs. 21.1 days, P <0.01). However, only 43% of drains were actively managed by IR. As a result, there was no significant change in the overall percentage of IR-removed drains compared to phase 1 (31 vs. 25%, P = 0.42). The inclusion of outpatients during phase 3 significantly increased overall active IR drain management (68% vs. 43%, P <0.01) and percentage of IR-removed drains (61% vs. 31%, P <0.01) compared to phase 2. There was also no significant adverse effect on dwell time with the addition of outpatients when compared to phase 2 (mean, 14.1 vs. 12.8 days, P = 0.51). For the entire 42 month analysis period, active IR drain management reduced mean drain dwell time by 4 days (13.7 vs. 17.7 days, P = 0.01) and more than doubled the percentage of IR-removed drains (61 vs. 25%, P <0.01).
Conclusion(s): Active IR drainage catheter management significantly decreases drain dwell time and increases the number of drains removed by IR. Reduction of dwell time has clear value for patients but further study is required to determine if this dwell time reduction and increased IR removal of drains have additional clinical benefits such as avoidance of surgery or recurrent infection.
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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.

PURPOSE/OBJECTIVE:To evaluate the changing use of transcatheter hemodialysis conduit procedures. METHODS:Multiple Centers for Medicare & Medicaid Services datasets were used to assess hemodialysis conduit angiography. Use was normalized per 100,000 beneficiaries and stratified by specialty and site of service. RESULTS:From 2001 to 2015, hemodialysis angiography use increased from 385 to 1,045 per 100,000 beneficiaries (compound annual growth rate [CAGR], +7.4%)]. Thrombectomy use increased from 114 to 168 (CAGR, +2.8%). Angiography and thrombectomy changed, by specialty, +1.5% and -1.3% for radiologists, +18.4% and +14.4% for surgeons, and +24.0% and +17.7% for nephrologists, respectively. By site, angiography and thrombectomy changed +29.1% and +20.7% for office settings and +0.8% and -2.4% for hospital settings, respectively. Radiologists' angiography and thrombectomy market shares decreased from 81.5% to 37.0% and from 84.2% to 47.3%, respectively. Angiography use showed the greatest growth for nephrologists in the office (from 5 to 265) and the greatest decline for radiologists in the hospital (299 to 205). Across states in 2015, there was marked variation in the use of angiography (0 [Wyoming] to 1173 [Georgia]) and thrombectomy (0 [6 states] to 275 [Rhode Island]). Radiologists' angiography and thrombectomy market shares decreased in 48 and 31 states, respectively, in some instances dramatically (eg, angiography in Nevada from 100.0% to 6.7%). CONCLUSIONS:Dialysis conduit angiography use has grown substantially, more so than thrombectomy. This growth has been accompanied by a drastic market shift from radiologists in hospitals to nephrologists and surgeons in offices. Despite wide geographic variability nationally, radiologist market share has declined in most states.

Purpose: To evaluate trends in transcatheter hemodialysis conduit procedures in the Medicare population over a recent 15-year interval. Materials: Aggregate national claims data were extracted from CMS PSPS Master Files from 2001-2015 for hemodialysis conduit angiography and thrombectomy procedures. Utilization was stratified by billing specialty and site of service. Additionally, individual claims data from 2004-2015 CMS 5% Research Identifiable Files were used to assess state-level utilization. Utilization was normalized per 100,000 Medicare fee-for-service beneficiaries. Result(s): From 2001-2015, hemodialysis conduit angiography utilization rates increased from 385 to 1,045 per 100,000 beneficiaries [compound annual growth rate (CAGR) +7.4%)], and thrombectomy rates increased from 114 to 168 (CAGR +2.8%). The CAGR for angiography was, by specialty, +1.5% for radiologists, +18.4% for surgeons, and +24.0% for nephrologists, and by site, +29.1% for office and +0.8% for hospital settings. Radiologists' overall market share of angiography decreased from 81.5% in 37.0%. By combination of specialty and site of service, angiography utilization growth was greatest for nephrologists in the office (from 5 to 265) and surgeons in the office (0 to 128). The greatest decline was for radiologists in the hospital (299 to 205). At the state level, there was marked heterogeneity in dialysis angiography utilization in 2015 [0 (Wyoming) to 1,1,73 (Georgia)], temporal change in angiography utilization from 2004-2015 [CAGR -100.0% (Wyoming) to +19.9% (Nevada)], and radiologists' 2015 market share [4.8% (Washington DC) to 100.0% (North Dakota)]. Nonetheless, radiologists' market share decreased in 49 states, and in some states dramatically (e.g., in Nevada, from 100.0% in 2004 to 6.7% in 2015). Conclusion(s): Transcatheter dialysis conduit angiography utilization has grown substantially, and more so than thrombectomy. This growth has been accompanied by a drastic market shift from radiologists in the hospital to nephrologists and surgeons in the office. Despite wide geographic heterogeneity across the U.S., decreasing radiologist market share has been observed in nearly every state.

Purpose: To evaluate the effect of free-text versus structured reporting on coding for interventional radiology procedures. Materials: Coding data from 2356 interventional radiology procedures performed in 2017 was retrospectively reviewed. Mandatory structured reports were implemented on July 1, 2017. Coding data from 1086 procedure reports from the six months prior to implementation and 1270 procedure reports from the six months after implementation were reviewed to assess changes in code usage. Result(s): Structured reporting increased the number of CPT codes per procedure (2.93 vs 3.90, p<0.01). Structured reporting increased the use of codes for fluoroscopic guidance for central venous catheter placement, ultrasound guidance for vascular access, time-based moderate sedation, and 3D rendering with interpretation (165 vs 343, 442 vs 1326, 273 vs 460, and 0 vs 10; p<0.01). Structured reporting had no significant impact on the usage of other codes like selective catheterization (120 vs 128). Conclusion(s): Implementation of mandatory structured reports for interventional radiology procedures increases the number of codes per report and increases usage of codes requiring documentation of specific criteria.

For many interventions, transradial access can be used as an alternative to transfemoral access. However, many operators who are proficient at transfemoral access may find transradial access unfamiliar and cumbersome. This Video (see Fig; available online at www.jvir.org) aims to demonstrate the basics of patient evaluation, preparation, and vascular access for transradial interventions.