Society Of Interventional Radiology Guidelines Research Articles

Real-world data to support post-market safety and performance of embolization coils: evidence generation from a medical device manufacturer and data institute partnership

BackgroundRecognizing the limitations of pre-market clinical data, regulatory authorities have embraced total product lifecycle management with post-market surveillance (PMS) data to assess medical device safety and performance. One method of proactive PMS involves the analysis of real-world data (RWD) through retrospective review of electronic health records (EHR). Because EHRs are patient-centered and focused on providing tools that clinicians use to determine care rather than collecting information on individual medical products, the process of transforming RWD into real-world evidence (RWE) can be laborious, particularly for medical devices with broad clinical use and extended clinical follow-up. This study describes a method to extract RWD from EHR to generate RWE on the safety and performance of embolization coils.MethodsThrough a partnership between a non-profit data institute and a medical device manufacturer, information on implantable embolization coils’ use was extracted, linked, and analyzed from clinical data housed in an electronic data warehouse from the state of Indiana’s largest health system. To evaluate the performance and safety of the embolization coils, technical success and safety were defined as per the Society of Interventional Radiology guidelines. A multi-prong strategy including electronic and manual review of unstructured (clinical chart notes) and structured data (International Classification of Disease codes), was developed to identify patients with relevant devices and extract data related to the endpoints.ResultsA total of 323 patients were identified as treated using Cook Medical Tornado, Nester, or MReye embolization coils between 1 January 2014 and 31 December 2018. Available clinical follow-up for these patients was 1127 ± 719 days. Indications for use, adverse events, and procedural success rates were identified via automated extraction of structured data along with review of available unstructured data. The overall technical success rate was 96.7%, and the safety events rate was 5.3% with 18 major adverse events in 17 patients. The calculated technical success and safety rates met pre-established performance goals (≥ 85% for technical success and ≤ 12% for safety), highlighting the relevance of this surveillance method.ConclusionsGenerating RWE from RWD requires careful planning and execution. The process described herein provided valuable longitudinal data for PMS of real-world device safety and performance. This cost-effective approach can be translated to other medical devices and similar RWD database systems.

Inversion of Central Venous Ports in Children Under Six Years Old: A Retrospective Analysis of 154 Oncology Patients.

Background Although some reports have evaluated the safety and efficacy of central venous port (CVP) placement in pediatric patients, the data about the inversion rate of the device and its risk factors are scarce. Therefore, this study aimed to evaluate the inversion rates of CVPs and their associated risk factors in pediatric patients. Methodology Between January 2010 and December 2021, 154 consecutive children (75 boys; median age, 28.5 months; range, 2-71 months) who underwent CVP placement at our center were included in this study. The primary outcome was the CVP inversion rate, and the secondary outcomes included technical success rate, intraoperative complications, and infectious complications. Intraoperative complications were evaluated according to the Society of Interventional Radiology guidelines. Patients under two years old were classified as the younger group and those aged ≥two years as the older group. Results The CVP inversion rate was 4.6% (n = 7/153), equivalent to 0.08 × 1,000 catheter-days. The inversion rate was significantly higher in the younger group (under two years old, 11.2%) than in the older group (≥two years old, 1.0%) according to the univariate analysis (p = 0.00576). The technical success rate was 99.4% (n = 153/154), and mild adverse events were observed during the procedure in three (1.9%) patients. Infectious complications were observed in 16 (10.5%) patients, equivalent to 0.19 × 1,000 catheter-days. Conclusions The CVP inversion rate was significantly higher in younger children (under two years old) than in older children (≥two years old).

Platelet and INR Thresholds and Bleeding Risk in Ultrasound Guided Percutaneous Liver Biopsy: A Before-After Implementation of the 2019 Society of Interventional Radiology Guidelines Observational Quality Improvement Study.

Purpose: To evaluate if implementation of the 2019 Society of Interventional Radiology (SIR) guidelines for periprocedural management of bleeding risk in patients undergoing percutaneous ultrasound guided liver biopsy is associated with increased haemorrhagic adverse events, change in pre-procedural blood product utilization, and evaluation of guideline compliance rate at a single academic institution. Methods: Ultrasound guided percutaneous liver biopsies from (January 2019-January 2023) were retrospectively reviewed (n = 504), comparing biopsies performed using the 2012 SIR pre-procedural coagulation guidelines (n = 266) to those after implementation of the 2019 SIR pre-procedural guidelines (n = 238). Demographic, preprocedural transfusion, laboratory, and clinical data were reviewed. Chart review was conducted to evaluate the incidence of major bleeding adverse events defined as those resulting in transfusion, embolization, surgery, or death. Results: Implementation of the 2019 SIR periprocedural guidelines resulted in reduced guideline non-compliance related to the administration of blood products, from 5.3% to 1.7% (P = .01). The rate of pre-procedural transfusion remained the same pre and post guidelines at 0.8%. There was no statistically significant change in the incidence of bleeding adverse events, 0.8% pre guidelines versus 0.4% post (P = 1.0). Conclusion: Implementation of the 2019 SIR guidelines for periprocedural management of bleeding risk in patients undergoing percutaneous ultrasound guided liver biopsy did not result in an increase in bleeding adverse events or pre-procedural transfusion rates. The guidelines can be safely implemented in clinical practice with no increase in major adverse events.

Guideline Compliance and Indications for Inferior Vena Cava Filter Placement at a Quaternary Care Medical Center.

This study investigated physician compliance with indications for inferior vena cava (IVC) filter placement according to the 2012 American College of Chest Physicians (ACCP) and the 2011 Society of Interventional Radiology (SIR) guidelines. A retrospective medical record review of 231 retrievable IVC filters placed between August 15, 2016, and December 28, 2017, at a large urban academic medical center. Guideline compliance to the 2012 ACCP and the 2011 SIR guidelines, and indications for IVC filter placements were assessed through an adjudication protocol. Filter retrieval and complication rates were also examined. Compliance to guidelines was low (60.2% for ACCP; 74.0% for SIR), especially for non-intensive care unit (ICU) patients (ICU 74.6% vs non-ICU 54.8%, p=0.007 for ACCP; ICU 82.5% vs non-ICU 70.8%, p=0.092 for SIR). After adjudication, 8.2% (19/231) of filters were considered non-indicated but reasonable, 17.7% (41/231) non-indicated and unreasonable, and 13.9% (32/231) SIR-indicated but not ACCP-indicated. The most common indication was venous thromboembolism with contraindication to anticoagulation. The most common reasons for non-compliance were distal deep venous thrombosis with contraindication to anticoagulation (19/60, 31.6%) and clot burden (19/60, 31.6%). One-year filter retrieval and 90-day complication rates were 32.0% (74/231) and 6.1% (14/231), respectively. Compliance to established guidelines was low. Reasons for non-compliance included limitations or discrepancies in guidelines, as well as non-evidence-based filter placements. Despite increasing utilization of inferior vena cava (IVC) filters, guideline compliance for IVC filter placement among providers is unclear. The results of this study indicate that physician compliance to established guidelines is poor, especially in non-intensive-care-unit patients. Noncompliance stems from non-evidence-based filter placement as well as differences and limitations in guidelines. Avoiding non-indicated IVC filter placement and consolidation of guidelines may significantly improve guideline compliance. The critical insights gained from this study can help promote judicious use of IVC filters and highlight the role of venous thromboembolism experts in navigating complex cases and nuances of guidelines.

Quantifying Change in Perfusion after Genicular Artery Embolization with Parametric Analysis of Intraprocedural Digital Subtraction Angiograms

PurposeTo quantify perfusion changes during genicular artery embolization (GAE) with the qualitatively described “pruning” technique using parametric analysis. Materials and MethodsA total of 12 patients underwent unilateral GAE with a total of 36 vessels embolized. Among 34 of the 36 vessels embolized, regions of interest (ROIs) were placed on parent vessels (PVs) and hyperemic target vessels (TVs) before and after GAE. For each ROI, peak intensity (PI), time to arrival (TTA), and area under the curve (AUC) were computed and compared between PV and TV. Volume of embolic administered was correlated with adverse events. ResultsNo change was seen in PI, TTA, and AUC in the PV after GAE. Reduction in AUC (1,495.7 ± 521.5 vs 1,667.4 ± 574.0; P << .01) and PI (195.1 ± 43.8 vs 224.3 ± 49.2; P << .01) with increase in TTA (3.42 s ± 1.70 vs 1.92 s ± 1.45; P << .01) within the TV were observed after GAE. Median follow-up time was 89 days (range, 21–254 days). Reduction in clinical symptoms was also noted based on the Western-Ontario and McMaster Universities Arthritis Index total and pain scale at 1 month (total, 42.9% ± 23.0; pain, 54.4% ± 9.8; P << .01) and 3 months (total, 42.5% ± 14.9; pain, 57.8% ± 10.6; P << .01). Eight total mild adverse events (minor/self-limiting) were noted per Society of Interventional Radiology guidelines. A larger volume of embolic was observed in knees with skin changes (3.4 mL ± 0.4 vs 1.7 mL ± 0.4; P << .001). Furthermore, all skin changes were seen with embolic volumes >3.0 mL. ConclusionsQuantification of intraprocedural perfusion changes with GAE demonstrated reduced flow to the TV with maintained flow in the PV and acceptable clinical outcomes. A potential relationship between embolic volume and nontarget embolization was also highlighted.

Limited ability of the renal ablation-specific (MC)2 risk scoring system to predict major adverse events from percutaneous renal microwave ablation

PurposeTo access if the (MC)2 scoring system can identify patients at risk for major adverse events following percutaneous microwave ablation of renal tumors. MethodsRetrospective review of all adult patients who underwent percutaneous renal microwave ablation at two centers. Patient demographics, medical histories, laboratory work, technical details of the procedure, tumor characteristics, and clinical outcomes were collected. The (MC)2 score was calculated for each patient. Patients were assigned to low-risk (<5), moderate-risk (5–8) and high-risk (>8) groups. Adverse events were graded according to the criteria from the Society of Interventional Radiology guidelines. ResultsA total of 116 patients (mean age = 67.8 [95%CI 65.5–69.9], 66 men) were included. 10 (8.6%) and 22 (19.0%) experienced major or minor adverse events, respectively. The mean (MC)2 score for patients with major adverse events (4.6 [95%CI 3.3–5.8]) was not higher than those with either minor adverse events (4.1 [95%CI 3.4–4.8], p = 0.49) or no adverse events (3.7 [95%CI 3.4–4.1], p = 0.25). However, mean tumor size was greater in those with major adverse events (3.1 cm [95%CI 2.0–4.1]) than minor adverse events (2.0 cm [95%CI 1.8–2.3], p = 0.01). Patients with central tumors were also more likely to experience major adverse events compared to those without central tumors (p = 0.02). The area under the receiver operator curve to predict major adverse events was 0.61 (p = 0.15), indicating a poor ability of the (MC)2 score to predict major adverse events. ConclusionThe (MC)2 risk scoring system does not accurately identify patients at risk for major adverse events from percutaneous microwave ablation of renal tumors. The mean tumor size and central tumor location may serve as a better indicator for risk assessment of major adverse events.

Factors Affecting Adverse Events after Venous Malformation Sclerotherapy

PurposeTo evaluate factors that contribute to adverse events (AEs) after embolization of venous malformations (VMs) using sclerosing agents. Materials and MethodsA retrospective review of patients who underwent direct puncture embolization of VMs with a sclerosing agent and adjunctive techniques, also termed as sclerotherapy, from 2016 to 2021 was performed. Three-hundred one embolizations in 137 patients (median age, 19.0 years; interquartile range, 12.8–31.5 years) were evaluated. The VM characteristics and embolization details were analyzed. Anticoagulation was also evaluated based on D-dimer levels. Cutaneous and noncutaneous AEs were analyzed. The AEs were categorized using Society of Interventional Radiology guidelines. ResultsVMs involving tissue planes were subcutaneous (n = 104), intramuscular (n = 84), and combined (n = 113). Overlying skin involvement was observed in 56% of the patients. Sodium tetradecyl sulfate was mainly used (83%). Periprocedural anticoagulation was used in 9% of the patients. Most AEs were minor (30/301, 9.7%), and only 1.7% (5/301) were major (21 cutaneous and 14 noncutaneous AEs). Age below 18 years (odds ratio, 4.4502; 95% confidence interval, 1.5607–12.6890; P = .0052) and overlying skin involvement (odds ratio, 7.1794; 95% confidence interval, 1.6226–31.7656; P = .0094) were factors associated with cutaneous AEs. All noncutaneous AEs developed in patients with intramuscular VMs; however, this association was not statistically significant. There was no severe hematologic AE or permanent consequence. ConclusionsThe overall AE rate after VM embolization was 11.6%; however, major AEs were rare (1.7%). Cutaneous AEs were associated with young age and overlying skin involvement. All noncutaneous AEs developed in patients with intramuscular VMs.

External Validation of the Percutaneous Renal Ablation Complexity Scoring System in Patients Undergoing Percutaneous Cryoablation or Microwave Ablation of Renal Tumors

PurposeTo assess the ability of the Percutaneous Renal Ablation Complexity (P-RAC) scoring system to predict procedural complexity or adverse events (AEs) in adult patients undergoing percutaneous thermal ablation of renal tumors. Materials and MethodsA retrospective review of 240 consecutive adult patients who underwent percutaneous thermal renal ablation from 2004 to 2018 was conducted. The P-RAC score was calculated for each renal tumor and procedural complexity recorded. A correlation coefficient was calculated for the P-RAC score and both the number of probes used and procedural duration. Receiver operating characteristic curves assessed the score’s ability to predict the use of adjunctive techniques and/or major AEs, classified according to the Society of Interventional Radiology guidelines. ResultsFor the entire cohort, there was a weak correlation between P-RAC scores and both the number of probes used (r = 0.31; P < .001) and procedural duration (r = 0.18; P = .03). When evaluating only patients treated with microwave ablation (MWA), no correlation between P-RAC scores and either the number of probes (P = .7) used or procedural duration (P = .4) was found. The area under the curve (AUC) for the P-RAC score to predict the use of adjunctive techniques was 0.55 and 0.53 for the entire cohort and MWA group, respectively. The AUC for the P-RAC score to predict major AEs was 0.70, 0.71, and 0.73 for the entire cohort, MWA group, and cryoablation group, respectively. ConclusionsThe P-RAC scoring system is limited in its ability to predict percutaneous thermal renal tumor ablation procedural complexity, especially in patients treated with MWA. The scoring system may have a role in identifying patients at risk of major AEs.

Impact of Portal Hypertension on Adverse Events after Splenic Arterial Aneurysm Embolization

PurposeTo evaluate the outcomes of splenic artery aneurysm (SAA) embolization and compare adverse event (AE) rates after embolization in patients with and without portal hypertension (PHTN). Materials and MethodsA retrospective review of all patients who underwent embolization of SAAs at 2 institutions was performed (34 patients from institution 1 and 7 patients from institution 2). Baseline demographic characteristics, preprocedural imaging, procedural techniques, and postprocedural outcomes were evaluated. Thirty-day postprocedural severe and life-threatening AEs were evaluated using the Society of Interventional Radiology guidelines. Thirty-day mortality and readmission rates were also evaluated. t test, χ2 test, and/or Fisher exact test were used for the statistical analysis. ResultsThere was no statistically significant difference between patients with and without PHTN in the location, number, and size of SAA(s). All procedures were technically successful. There were 13 (32%) patients with and 28 (68%) patients without PHTN. The 30-day mortality rate (31% vs 0%; P = .007), readmission rates (61% vs 7%; P < .001), and severe/life-threatening AE rates (69% vs 0%; P < .001) were significantly higher in patients with PHTN than in those without PHTN. ConclusionsThere was a significantly higher mortality and severe/life-threatening AE rate in patients with PHTN than in those without PHTN. SAAs in patients with PHTN need to be managed very cautiously, given the risk of severe/life-threatening AEs after embolization.

Analysis of factors affecting the diagnostic yield of image-guided percutaneous core needle biopsy for peritoneal/omental lesions.

To evaluate the diagnostic yield, safety, and factors associated with the diagnostic yield of percutaneous core needle biopsy (PNB) for peritoneal/omental lesions. Consecutive 297 patients (67 men, 230 women; median age, 64years [range 15-87]) who underwent a PNB for 311 peritoneal/omental lesions at a single center from April 2010 to March 2020 were evaluated retrospectively. The preprocedural CT findings, diagnostic yield, sensitivity, specificity, PPV, NPV, technical success rate, and adverse events were analyzed. Surgical or clinical diagnosis with follow-up was the diagnostic reference standard. Adverse events were evaluated using the Society of Interventional Radiology guidelines. The median anteroposterior (AP) diameter and CT value of the target lesion were 24mm (range 5-78) and 46 HU (range -75 to 140), respectively. Ascites was interposed on the puncture route in 106 patients (34.1%). The technical success rate was 100%. The diagnostic yield, sensitivity, specificity, PPV, and NPV were 93.9%, 93.8%, 100%, 100%, and 20.8%, respectively. Minor complications were observed following five procedures (1.6%). The diagnostic yield was lower for fat-dominant lesions than for other lesions (82.6% vs. 95.8%, p = 0.002). The diagnostic PNB group had a greater AP diameter than did the non-diagnostic PNB group (27.3 ± 13.0 vs. 20.7 ± 8.4mm, p = 0.037). PNB for peritoneal/omental lesions provided a sufficiently high diagnostic yield and minimal adverse events. Lesions with a greater AP diameter and a higher density on CT would provide more diagnostic specimens from this technique.

Adherence to the RIGHT statement in Society of Interventional Radiology guidelines.

The Reporting Items for Practice Guidelines inHealth Care (RIGHT) Statement was developed by a multidisciplinary team of experts to improve reporting quality and transparency in clinical practice guideline development. To assess the quality of reporting in clinical practice guidelines put forth by the Society of Interventional Radiology (SIR) and their adherence to the RIGHT statement checklist. In March 2018, using the 22 criteria listed in the RIGHT statement, two researchers independently documented adherence to each item for all eligible guidelines listed by the SIR by reading through each guideline and using the RIGHT statement elaboration and explanation document as a guide to determine if each item was appropriately addressed as listed in the checklist. To qualify for inclusion in this study, each guideline must have met the strict definition for a clinical practice guideline as set forth by the National Institute of Health and the Institute of Medicine, meaning they were informed by a systematic review of evidence and intended to direct patient care and physician decisions. Guidelines were excluded if they were identified as consensus statements, position statements, reporting standards, and training standards or guidelines. After exclusion criteria were applied, the two researchers scored each of the remaining clinical practice guidelines (CPGs) using a prespecified abstraction Google form that reflected the RIGHT statement checklist (22 criteria; 35 items inclusive of subset questions). Each item on the abstraction form consisted of a "yes/no" option; each item on the RIGHT checklist was recorded as "yes" if it was included in the guideline and "no" if it was not. Each checklist item was weighed equally. Partial adherence to checklist items was recorded as "no." Data were extracted into Microsoft Excel (Microsoft Corporation) for statistical analysis. The initial search results yielded 129 CPGs in thefollowing areas: 13 of the guidelines were in the field of interventional oncology; 16 in neurovascular disorders; five in nonvascular interventions; four in pediatrics; 25 in peripheral, arterial, and aortic disease; one in cardiac; one in portal and mesenteric vascular disease; 37 in practice development and safety; three in spine and musculoskeletal disorders; 14 in venous disease; five in renal failure/hemodialysis; and five in women's health. Of the 46 guidelines deemed eligible for evaluation by the RIGHT checklist, 12 of the checklist items showed less than 25% adherence and 13 showed more than 75% adherence. Of 35 individual RIGHT statement checklist items, adherence was found for a mean (SD) of 22.9 items (16.3). The median number of items with adherence was 21 (interquartile range, 7.5-38). The quality of reporting in interventional radiology guidelines is lacking in several key areas, including whether patient preferences were considered, whether costs and resources were considered, the strength of the recommendations, and the certainty of the body of evidence. Poor adherence to the RIGHT statement checklist in these guidelines reveals many areas for improvement in guideline reporting.

Factors Associated With Local Tumor Control and Complications After Thermal Ablation of Colorectal Cancer Liver Metastases: A 15-year Retrospective Cohort Study

IntroductionThe purpose of this study was to identify risk factors associated with local tumor progression-free survival (LTPFS) and complications after colorectal liver metastases (CLM) thermal ablation (TA). Patients and MethodsThis retrospective analysis included 286 patients with 415 CLM undergoing TA (radiofrequency and microwave ablation) in 378 procedures from January 2003 to July 2017. Prior hepatic artery infusion (HAI), bevacizumab, pre-existing biliary dilatation, ablation modality, minimal ablation margin (MM), prior hepatectomy, CLM number, and size were analyzed as factors influencing complications and LTPFS. Statistical analysis included the Kaplan-Meier method, Cox proportional hazards model, competing risk analysis, univariate/multivariate logistic/exact logistic regressions, and the Fisher exact test. Complications were reported according to modified Society of Interventional Radiology guidelines. ResultsThe median follow-up was 31 months. There was no LTP for MM > 10 mm. Smaller tumor size, increased MM, and prior hepatectomy correlated with longer LTPFS. The major complications occurred following 28 (7%) of 378 procedures. There were no biliary complications in HAI-naive patients, versus 11% in HAI patients (P < .001), of which 7% were major. Biliary complications predictors in HAI patients included biliary dilatation, bevacizumab, and MM > 10 mm. In HAI patients, ablation with 6 to 10 mm and > 10 mm MM resulted in major biliary complication rates of 4% and 21% (P = .0011), with corresponding LTP rates of 24% and 0% (P = .0033). In HAI-naive patients, the LTP rates for 6 to 10 mm and > 10 mm MM were 27% and 0%, respectively. ConclusionsNo LTP was seen for MM > 10 mm. Biliary complications occurred only in HAI patients, especially in those with biliary dilatation, bevacizumab, and MM > 10 mm. In HAI patients, MM of 6 to 10 mm resulted in 76% local tumor control and 4% major biliary complications incidence.

Caval pseudoaneurysms following complex inferior vena cava filter removal: Clinical significance and patient outcomes.

To investigate the incidence and clinical significance of caval pseudoaneurysm and extravasation post-complex inferior vena cava filter retrieval. A total of 83 patients (70% female, average age 56) underwent complex inferior vena cava filter retrieval between January 2015 and December 2019 utilizing either rigid endobronchial forceps (n = 69, 83%) and/or excimer laser (n = 20, 24%). Procedural variables were recorded. The incidence and size of caval pseudoaneurysms and extravasation along with treatment type and clinical outcomes were analyzed. Technical success in all cases was 96% (n = 80). Average fluoroscopy time was 23 min (median: 20.2, range: 0.9-129.5). Average filter dwell time was 85 months (range: 2-316 months). Caval pseudoaneurysm was detected on post-retrieval venography in 10 patients (12%) and frank extravasation occurred in 1 case (1%). Average pseudoaneurysm length and width was 20.4 mm (range: 5-45 mm) and 12.9 mm (range: 4-24 mm), respectively. Pseudoaneurysms occurred most frequently during the removal of Optease (n = 5) and Celect (n = 2) filters. The pseudoaneurysms completely resolved with prolonged (>5 min) balloon angioplasty in all but one instance where a small portion of the pseudoaneurysm persisted. This patient was admitted and observed overnight before being discharged without complication. The solitary case of significant extravasation was effectively managed with immediate stent placement and the patient remained hemodynamically stable. Radiographically detectable caval pseudoaneurysm and extravasation is not uncommon in complex inferior vena cava filter retrieval and, despite being considered a major complication by Society of Interventional Radiology guidelines, can often be managed without stenting or other invasive treatment.

Percutaneous Image-Guided Biopsy of the Spleen: Experience at a Single Tertiary Care Center.

The purpose of this study is to assess the complication rate of percutaneous image-guided biopsy of the spleen at our institution and to evaluate for variables associated with complication rate. This is a Research Ethics Board approved retrospective study of consecutive patients who underwent image-guided biopsy of the spleen at our institution from January 2010 to November 2019. Complications, imaging findings, and pathologic diagnosis were reviewed. Complications (major and minor) were classified per Society of Interventional Radiology Guidelines, and complication rate was calculated. Logistic regression was applied to determine factors associated with complications. Diagnostic yield was calculated. In all, 55 patients (28 female) underwent splenic biopsy using ultrasound guidance. The most common indication was possible lymphoma in 41 (71.7%) patients followed by query metastasis 18 (31.5%) patients. Core biopsies (18 g/20 g) were done in 53 (92%) cases, and fine-needle aspiration (22 g) was performed in 4 (8%). The median number of samples collected was 4 (range: 2-9). The results were diagnostic in 54 cases (94.7%, 95% confidence interval [CI]: 88.7-100.0). There were 12 (21%, 95% CI: 10.1-31.9) patients with minor complications and 2 (3.5%, 95% CI: 0.0-8.4) with major complications (2 splenic bleeds requiring embolization, no splenectomy, or deaths). No variables (needle size, lesion size, and number of passes) were associated with complication rate. Percutaneous image-guided biopsy of the spleen at a single tertiary care institution demonstrates major complication rate comparable to that in the literature with no variables associated with complication rate; there were no cases of splenectomy or death.

4:03 PM Abstract No. 206 The risk factors for major bleeding following ultrasound-guided native renal biopsy: what is the “core” of the problem? A case-control study

To identify risk factors for major bleeding following ultrasound (US)-guided random renal biopsy by microscopic analysis and comparison of the cores obtained in patients with and without bleeding. A retrospective review identified 17 of 179 patients (9.50%) with major bleeding complications (per criteria determined by the Society of Interventional Radiology guidelines) post-US-guided native renal biopsy between July 2014 and June 2019. Case-control matching was accomplished by propensity score based on sex, age, body mass index (BMI), blood pressure (BP), international normalized ratio (INR), platelet (PLT), blood urea nitrogen (BUN), and creatinine (Cr) concentration, estimated glomerular filtration rate (eGFR), needle size, and core number. The cores obtained in the bleed and non-bleed patients were analyzed for total length, medullary length, cortical thickness, and number of arcuate/interlobular vessels by the pathologist. 26 controls were matched to 17 cases (with and without major hemorrhage, respectively). Conditional logistic regression was used to explore the statistical significance between core characteristics obtained from random renal biopsies and the probability of a major bleed. Analysis revealed that arcuate artery (AA) quantity per specimen exhibits a significant association with a major bleed (P = 0.0006). When 0, 1, or ≥ 2 AA were identified, the frequency of major bleeding was 13.04%, 66.67%, and 75.00%, respectively. The odds of major bleed are 6 times higher with 1 AA (95% CI, 1.28 – 32.30) and 15 times higher with ≥ 2 AAs (95% CI, 1.41 – 169.57). Despite lacking statistical significance, correlations between medullary length (P = 0.228), medulla-cortex (MC) (P = 0.089), medulla-total (MT) (P = 0.108), and cortex-total (CT) (P = 0.112) length ratios to major bleeding may require a larger population study. A strong and incremental correlation between major renal hemorrhage following native renal biopsy and the number of arcuate arteries per core specimen exists. Identification of arcuate arteries by the pathologist while assessing sample adequacy in the US suite can help predict major hemorrhage in patients undergoing random renal biopsies.

PERCUTANEOUS FLUOROSCOPICALLY-GUIDED TRANSCERVICAL RETROGRADE ACCESS FACILITATES SUCCESSFUL THORACIC DUCT EMBOLIZATION AFTER FAILED ANTEGRADE TRANSABDOMINAL ACCESS

The purpose of this study was to demonstrate the feasibility of percutaneous fluoroscopically-guided transcervical retrograde access into the thoracic duct following unsuccessful transabdominal cisterna chyli cannulation to perform thoracic duct embolization for the treatment of chylothorax. Five patients, including three (60%) women and two (40%) men, with median age of 62 years, underwent percutaneous transcervical thoracic duct access and embolization after failed transabdominal cisterna chyli cannulation for the treatment of chylothorax. In all patients, fluoroscopically-guided percutaneous transcervical retrograde access into the distal thoracic duct was achieved using a 21-gauge needle and an 0.018-inch wire. Following advancement of a microcatheter, retrograde lymphangiography was performed to identify the location of thoracic duct injury. A combination of 2:1 ethiodized oil to cyanoacrylate mixtures, platinum microcoils, or stent-grafts were used to treat the chylous leaks. Technical successes, procedure durations, fluoroscopy times, blood losses, immediate adverse events, clinical successes, and follow-up durations were recorded. Technical success was defined as cannulation of the distal thoracic duct using a transcervical approach followed by treatment of the thoracic duct injury. Adverse events were classified according to the Society of Interventional Radiology guidelines. Clinical success was defined as resolution of the presenting chylothorax. Percutaneous transcervical retrograde thoracic duct access and treatment was technically successful in all patients (n=5). Median procedure duration was 173 minutes (range: 136-347 minutes) with a median fluoroscopy time of 94.7 minutes (range: 47-125 minutes). Median blood loss was 10 mL (range: 5-20 mL). No minor or major adverse occurred. Clinical success was achieved in all patients (n=5). Median follow-up was 372 days (range: 67-661 days). Percutaneous fluoroscopically- guided transcervical retrograde thoracic duct access is an effective and safe method to perform thoracic duct embolization following unsuccessful transabdominal cisterna chyli cannulation for the treatment of chylothorax.

Role of Percutaneous Nephrostomy in Bladder Carcinoma with Obstructive Uropathy: A Story Revisited.

Objective:To evaluate the role of percutaneous nephrostomy (PCN) in patients of carcinoma bladder presenting with obstructive uropathy.Material and Methods:We evaluated medical records of 33 patients of bladder cancer with obstructive uropathy that presented to a tertiary care hospital in north India from January 2015 to December 2016. Outcome measures included technical success rates, change in blood urea and serum creatinine (measured on Day 1, 7, and 14); and complications of PCN according to Society of Interventional Radiology Guidelines for Percutaneous Nephrostomy.Results:PCN was done in 30 patients. The mean age of patients was 51 years (range 42-67). 24 patients were male and 6 patients were female. The technical success rates for PCN placement were 93.33%. In 12 patients there was no improvement after PCN insertion. Improvement in clinical condition/kidney function occurred in 18 patients. Out of these 6 patients underwent radical cystectomy with ileal conduit formation and palliative radiotherapy/chemotherapy was given to 5 cases. In the remaining 7 patients, after an initial improvement that lasted for 2 weeks after PCN progressive renal dysfunction developed due to malignancy. Minor complications of PCN were seen in 16.6% of patients and major complications were seen in 10 % of cases.Conclusion:In selected patients with bladder carcinoma with obstructive uropathy, PCN insertion may improve kidney function tests to normal levels and enable them to receive tumor-specific curative/palliative treatment.

The results of ultrasound-guided percutaneous nephrostomy tube placement for obstructive uropathy: A single-centre 10-year experience

The aim of this study was to determine the results of ultrasound-guided percutaneous nephrostomy tube placement performed solely by urologists. We present our relevant one decade experience in a tertiary care hospital. We evaluated technical success and complication rates of ultrasound-guided percutaneous nephrostomy tube placement for obstructive uropathy in our clinic, between December 2004 and January 2015. Data were retrieved retrospectively from patients' files. This procedure was performed by urologists and two different methods for renal access were employed: Seldinger technique and direct puncture technique. Percutaneous nephrostomy tube placement was considered successful if the tube was placed in the renal pelvis and drained urine spontaneously and adequately. Complications were classified according to the Guideline of Society of Interventional Radiology Guidelines for Percutaneous Nephrostomy. Four hundred and fifteen percutaneous nephrostomy tube placements were performed in 354 patients (165 men and 159 women) suffering from obstructive uropathy due to several benign (57.3%) or malign (42.7%) diseases. The mean age in this study group was 43.2 years (range 27 to 81). We were found that 228 procedures were performed by using the Seldinger technique and 187 using direct puncture technique. The overall technical success, major and minor complications rates were 96.1%, 11.1%, and 7.7%, respectively. The Seldinger technique and direct puncture technique were compared: technical success rate was 97.8% vs. 94.1% (p=0.052). There was no difference between the two techniques in terms of major and minor complication rates. Ultrasound-guided percutaneous nephrostomy tube placement is a safe, easy and effective technique for providing temporary or permanent drainage of an obstructed renal pelvi-calyceal system. This procedure can be performed effectively and safely by an urologist.

4:21 PM Abstract No. 370 Transfemoral transcaval core-needle liver biopsy: safety and efficacy in over 200 cases

To investigate the safety, efficacy, and outcomes of transfemoral transcaval (TFTC) core-needle liver biopsies. We previously published our results of the first 66 patients using TFTC as an alternative to transjugular liver biopsy, where hepatic tissue is directly obtained through the intrahepatic inferior vena cava via a femoral venous approach. In this retrospective study, the medical, surgical, and radiological records of patients who underwent transvenous liver biopsies at a single institution between February 2014 and August 2017 was performed. This is a follow-up study where we present the outcomes and complications of over 200 patients. Procedural complications were classified according to the Society of Interventional Radiology guidelines. 204 total TFTC liver biopsies (61.5% male; mean age 51.1 ± 15.5 years) accounted for 75.0% (204/272) of the transvenous liver biopsies. Technical success was achieved in 98.5% (201/204) of cases. Histopathologic diagnoses were made in 198 cases (97.1%). Fragmented or limited samples in which a pathological diagnosis was still made occurred in 6 cases (3.0%). Complications occurred in 4 cases (1.9%). There was one case with a small subhepatic hematoma, not requiring any transfusion and one case with delayed bleeding at the femoral puncture site requiring a blood transfusion that was successfully treated with a figure eight stitch. Venous pressure measurements were requested in 171 cases and were successfully obtained in all. TFTC core-needle liver biopsy is a safe and highly effective method of obtaining hepatic tissue samples and venous pressure measurements.

A Review of Antibiotic Prophylaxis for Interventional Radiology Procedures and Identification of Antimicrobial Stewardship Opportunities

BackgroundAntibiotics used for peri-procedural prophylaxis are dispensed by providers or nurses from automated dispensing machines in the interventional radiology (IR) suites. These antibiotics are administered without pharmacist review which skips a critical point in time for antimicrobial stewardship intervention. The purpose of this study was to evaluate antibiotic prophylaxis for IR procedures and identify opportunities for antimicrobial stewardship.MethodsAll patients who underwent an IR procedure and received antibiotic prophylaxis from April 2016 to April 2017 were identified. We performed a manual chart review to determine procedure type, antibiotic prophylaxis, concomitant systemic antibiotics, and antibiotic concordance with the Society of Interventional Radiology (SIR) guidelines.ResultsThere were 410 IR procedures where the patient received a single prophylactic antibiotic dose; 261 were inpatient procedures. See Table 1 for procedure and antibiotic data. There were 74 patients (18%) who concomitantly received systemic antibiotics. There were 126 cases (31%) discordant with the SIR guidelines. Reasons for discordance include prophylaxis not recommended, inappropriate antibiotic selection, or patient already receiving an antibiotic with similar spectrum of coverage.ConclusionAntibiotics are frequently administered as prophylaxis for IR procedures. For many IR procedures, data to support prophylaxis is limited; however, there are opportunities for antimicrobial stewardship intervention which include optimizing antibiotic selection and withholding prophylaxis when not indicated or when patients are receiving systemic antibiotics.Table 1ProcedureNo. of procedures, n = 410Routine prophylaxis recommended (y/n), antibioticAntibiotic dosesTunneled line or port placement181No consensusCFZ 162 VAN 8 LVX 6 CRO 5Genitourinary59Yes, no consensusCRO 43 LVX 14 CFZ 2Gastrointestinal or abscess drainage55Yes, no consensusCRO 36 LVX 10 CFZ 9Embolization or chemoembolization44Yes, no consensusCRO 22 CFZ 18 LVX 2 VAN 2Gastrostomy tube placement40Yes, CFZCFZ 30 CRO 7 LVX 2 VAN 1Vascular28No, noneCFZ 23 CRO 4 LVX 1Biopsy3No, noneCFZ 2 CRO 1CFZ, cefazolin; CRO, ceftriaxone; LVX, levofloxacin; VAN, vancomycin.Disclosures All authors: No reported disclosures.