Efficacy and Safety of Radiation Segmentectomy with 90Y Resin Microspheres for Hepatocellular Carcinoma.

Background Limited data are available on radiation segmentectomy (RS) for treatment of hepatocellular carcinoma (HCC) using yttrium 90 (90Y) resin microsphere doses determined by using a single-compartment medical internal radiation dosimetry (MIRD) model. Purpose To evaluate the efficacy and safety of RS treatment of HCC with 90Y resin microspheres using a single-compartment MIRD model and correlate posttreatment dose with outcomes. Materials and Methods This retrospective single-center study included adult patients with HCC who underwent RS with 90Y resin microspheres between July 2014 and December 2022. Posttreatment PET/CT and dosimetry were performed. Adverse events were assessed using the Common Terminology Criteria for Adverse Events, version 5.0. Per-lesion and overall response rates (ie, complete response [CR], objective response, disease control, and duration of response) were assessed at imaging using the Modified Response Evaluation Criteria in Solid Tumors, and overall survival (OS) was assessed using Kaplan-Meier analysis. Results Among 67 patients (median age, 69 years [IQR, 63-78 years]; 54 male patients) with HCC, median tumor absorbed dose was 232 Gy (IQR, 163-405 Gy). At 3 months, per-lesion and overall (per-patient) CR was achieved in 47 (70%) and 41 (61%) of 67 patients, respectively. At 6 months (n = 46), per-lesion rates of objective response and disease control were both 94%, and per-patient rates were both 78%. A total of 88% (95% CI: 79 99) and 72% (95% CI: 58, 90) of patients had a per-lesion and overall duration of response of 1 year or greater. At 1 month, a grade 3 clinical adverse event (abdominal pain) occurred in one of 67 (1.5%) patients. Median posttreatment OS was 26 months (95% CI: 20, not reached). Disease progression at 2 years was lower in the group that received 300 Gy or more than in the group that received less than 300 Gy (17% vs 61%; P = .047), with no local progression in the former group through the end of follow-up. Conclusion Among patients with HCC who underwent RS with 90Y resin microspheres, 88% and 72% achieved a per-lesion and overall duration of response of 1 year or greater, respectively, with one grade 3 adverse event. In patients whose tumors received 300 Gy or more according to posttreatment dosimetry, a disease progression benefit was noted. © RSNA, 2024 Supplemental material is available for this article.

Safety profile and technical success of narrow window CT-guided percutaneous biopsy with blunt needle approach in the abdomen and pelvis.

OBJECTIVE: To assess success and safety of CT-guided procedures with narrow window access for biopsy. METHODS: Three hundred ninety-six consecutive patients undergoing abdominal or pelvic CT-guided biopsy or fiducial placement between 01/2015 and 12/2018 were included (183 women, mean age 63 ±â€¯14 years). Procedures were classified into "wide window" (width of the needle path between structures > 15 mm) and "narrow window" (≤ 15 mm) based on intraprocedural images. Clinical information, complications, technical and clinical success, and outcomes were collected. The blunt needle approach is preferred by our interventional radiology team for narrow window access. RESULTS: There were 323 (81.5%) wide window procedures and 73 (18.5%) narrow window procedures with blunt needle approach. The median depth for the narrow window group was greater (97 mm, interquartile range (IQR) 82-113 mm) compared to the wide window group (84 mm, IQR 60-106 mm); p = 0.0017. Technical success was reached in 100% (73/73) of the narrow window and 99.7% (322/323) of the wide window procedures. There was no difference in clinical success rate between the two groups (narrow: 86.4%, 57/66; wide: 89.5%, 265/296; p = 0.46). There was no difference in immediate complication rate (narrow: 1.3%, 1/73; wide: 1.2%, 4/323; p = 0.73) or delayed complication rate (narrow: 1.3%, 1/73; wide: 0.6%, 1/323; p = 0.50). CONCLUSION: Narrow window (< 15 mm) access biopsy and fiducial placement with blunt needle approach under CT guidance is safe and successful. CLINICAL RELEVANCE STATEMENT: CT-guided biopsy and fiducial placement can be performed through narrow window access of less than 15 mm utilizing the blunt-tip technique. KEY POINTS: • A narrow window for CT-guided abdominal and pelvic biopsies and fiducial placements was considered when width of the needle path between vital structures was ≤ 15 mm. • Seventy-three biopsies and fiducial placements performed through a narrow window with blunt needle approach had a similar rate of technical and clinical success and complications compared to 323 procedures performed through a wide window approach, with traditional approach (> 15 mm). • This study confirmed the safety of the CT-guided percutaneous procedures through < 15 mm window with blunt-tip technique.

Highest 3-month international normalized ratio (INR): a predictor of bleeding following ultrasound-guided liver biopsy.

OBJECTIVES: To determine whether international normalized ratio (INR), bilirubin, and creatinine predict bleeding risk following percutaneous liver biopsy. METHODS: A total of 870 consecutive patients (age 53 ± 14 years; 53% (459/870) male) undergoing non-targeted, ultrasound-guided, percutaneous liver biopsy at a single tertiary center from 01/2016 to 12/2019 were retrospectively reviewed. Results were analyzed using descriptive statistics and logistic regression models to evaluate the relationship between individual and combined laboratory values, and post-biopsy bleeding risk. Receiver operating characteristic (ROC) curves and area under ROC (AUC) curves were constructed to evaluate predictive ability. RESULTS: Post-biopsy bleeding occurred in 2.0% (17/870) of patients, with 0.8% (7/870) requiring intervention. The highest INR within 3 months preceding biopsy demonstrated the best predictive ability for post-biopsy bleeding and was superior to the most recent INR (AUC = 0.79 vs 0.61, p = 0.003). Total bilirubin is an independent predictor of bleeding (AUC = 0.73) and better than the most recent INR (0.61). Multivariate regression analysis of the highest INR and total bilirubin together yielded no improvement in predictive performance compared to INR alone (0.80 vs 0.79). The MELD score calculated using the highest INR (AUC = 0.79) and most recent INR (AUC = 0.74) were similar in their predictive performance. Creatinine is a poor predictor of bleeding (AUC = 0.61). Threshold analyses demonstrate an INR of > 1.8 to have the highest predictive accuracy for bleeding. CONCLUSION: The highest INR in 3 months preceding ultrasound-guided percutaneous liver biopsy is associated with, and a better predictor for, post-procedural bleeding than the most recent INR and should be considered in patient risk stratification. CLINICAL RELEVANCE STATEMENT: Despite correction of coagulopathic indices, the highest international normalized ratio within the 3 months preceding percutaneous liver biopsy is associated with, and a better predictor for, bleeding and should considered in clinical decision-making and determining biopsy approach. KEY POINTS: • Bleeding occurred in 2% of patients following ultrasound-guided liver biopsy, and was non-trivial in 41% of those patients who needed additional intervention and had an associated 23% 30-day mortality rate. • The highest INR within 3 months preceding biopsy (AUC = 0.79) is a better predictor of bleeding than the most recent INR (AUC = 0.61). • The MELD score is associated with post-procedural bleeding, but with variable predictive performance largely driven by its individual laboratory components.

Percutaneous CT-Guided Cryoablation for Locally Recurrent Prostate Cancer: Technical Feasibility, Safety, and Effectiveness.

PURPOSE: To assess the feasibility and safety of using computed tomography (CT) guidance for ablation of prostate cancer in the salvage setting. MATERIALS AND METHODS: This institutional review board-approved retrospective study of consecutive patients who presented with prostate cancer recurrence and underwent percutaneous CT-guided cryoablation was conducted between July 2020 and September 2022. A total of 18 patients met the inclusion criteria, and a total of 19 procedures were performed. Demographic details; preablation and postablation urinary, rectal, and erectile function assessment; procedure details; and preoperative and postoperative imaging findings and prostate-specific antigen (PSA) values were recorded. RESULTS: The mean treated tumor size was 15.7 mm ± 6.2. Technical success was achieved in 18 of the 19 procedures (94.7%), with 1 procedure aborted due to inability to obtain a safe plane. The mean follow-up time was 10.0 months (range, 2.3-26.7 months) at the time of manuscript preparation. The mean PSA before ablation was 8.1 ng/mL ± 9.3, and postablation PSA nadir was 2.6 ng/mL ± 4.0 (P = .002). Of the 18 patients who had postoperative imaging, 16 (88.9%) had a complete response (ie, no evidence of residual disease), and 2 (11.1%) patients had residual disease. Overall, 16 (88.9%) of the 18 treated patients demonstrated a PSA and/or imaging response to ablation. Mild adverse events occurred in 4 (22%) of the 18 cases. CONCLUSIONS: CT-guided cryoablation appears to be a technically feasible, safe option for treating locally recurrent prostate cancer.

The Impact of Implementation of a Commercial Inferior Vena Cava Filter Database Program on Filter Retrieval versus Physician Tracking over a 9-Year Period: A Retrospective, Observational Study.

PURPOSE: To compare the impact of a commercial tracking database on inferior vena cava filter retrievals with that of physician tracking and no tracking. MATERIALS AND METHODS: From January 2013 to December 2021, 532 filters were placed at a single institution and followed in 3 phases: (a) Phase 1, pretracking (January 1, 2013, to February 28, 2015); (b) Phase 2, commercial database tracking (March 1, 2015, to June 30, 2019); and (c) Phase 3, commercial database tracking with separate tracking by an interventional radiologist (July 1, 2019, to December 31, 2021). Patients excluded from the commercial database due to human error served as a control group. Outcomes of commercial database entry, 2-year filter retrieval rates, dwell times, and factors contributing to retrieval candidacy were collected. RESULTS: Two-year retrieval rates in Phases 1, 2 and 3 were 20%, 31%, and 46%, respectively (Phase 1 vs 2, P = .04; Phase 2 vs 3, P = .009). Median dwell times across Phases 1, 2, and 3 were 168 days (4-1,313 days), 140 days (3-1,988 days), and 188 days (13-734 days) (P = .33), respectively. There was no difference in retrieval rates (P = .86) and dwell times (P = .50) between patients enrolled in the database group and those enrolled in the control group. Across all phases, 48% of patients enrolled in the database were not successfully contacted, and only 6% were categorized as "likely to consult" filter retrieval. During Phase 3, 100% of patients achieved a retrieval disposition. CONCLUSIONS: A commercial tracking database had low success rates of contacting patients and did not increase filter retrieval rates relative to those in the control group; however, physician tracking increased retrieval rates.

Utility of Intraoperative Neuromonitoring to Protect Against Adjacent Nerve Injury in Musculoskeletal and Lymph Nodal Cryoablation.

PURPOSE: To demonstrate the utility of intraoperative neuromonitoring (IONM) as an effective method of passive thermoprotection against cryogenic injury of neural structures during musculoskeletal and lymph node cryoablation. MATERIAL AND METHODS: 29 patients (16 male, mean age and range, M: 68.6 and 45-90, F: 62.6 and 28-88) underwent 33 cryoablations of musculoskeletal and lymph node lesions. Transcranial electrical motor evoked potentials (MEPs) and somatosensory evoked potentials (SSEPs) of target nerves were recorded throughout the ablations. Significant change was defined as waveform amplitude reduction greater than 30% (MEP) and 50% (SSEP). The primary outcomes of this study were immediate post-procedural neurological deficits and frequency of significant MEP and SSEP amplitude reductions. RESULTS: Significant amplitude reductions were detected in 54.5% (18/33) of MEP tracings and 0% (0/33) of SSEP tracings. Following each occurrence of significant amplitude reductions, freeze cycles were promptly terminated. Intra-procedurally, 13 patients had full recovery of amplitudes to baseline, 11 of which had additional freeze cycles completed. In 5/33 (15.2%) of cryoablations, there were immediate post-procedure neurological deficits (Moderate Adverse Events). Unrecovered MEPs conferred a relative risk for neurological sequela of 23.2 (95% confidence interval [CI], 3.22-167.21; P=0.0009) vs. those with recovered MEPs. All five patients had complete neurologic recovery by twelve months. CONCLUSION: IONM is a reliable, safe method of passive thermoprotection of neurological structures during cryoablation. It provides early detection of changes in nerve conduction, which when addressed quickly, may result in complete restoration of MEP signals within the procedure and minimize risk of cryogenic neural injury.

Association between Patient Experience Scores and Low Utilization of Hepatocellular Carcinoma Treatment in the United States: A Surveillance, Epidemiology, and End Results-Consumer Assessment of Healthcare Providers and Systems Analysis (SEER-CAHPS).

PURPOSE: To study the experiences of patients with hepatocellular carcinoma (HCC) contributing to treatment discrepancy in the United States. MATERIALS AND METHODS: Using Surveillance, Epidemiology, and End Results data from National Cancer Institute (NCI), Medicare (2002-2015) beneficiaries with HCC who completed a Consumer Assessment of Healthcare Providers and Systems (CAHPS) survey were included. Six CAHPS items (3 global scores: global care rating [GCR], primary doctor rating [PDR], and specialist rating [SR]; 3 composite scores: getting needed care [GNC], getting care quickly [GCQ], and doctor communication [DC]) assessed patient experience. Covariates assessed between treated and nontreated groups included patient, disease, hospital, and CAHPS items. RESULTS: Among 548 patients with HCC, 211 (39%) received treatment and 337 (61%) did not receive treatment. Forty-two percent (GCR), 29% (PDR), 30% (SR), 36% (GNC), 78% (GCQ), and 35% (DC) of patients reported less-than-excellent experiences on the respective CAHPS items. Chronic liver disease (CLD) was present in 52% and liver decompensation (LD) in 60%. A minority of the hospitals were NCI-designated cancer centers (47%), transplant centers (27%), and referral centers (9%). On univariable analysis, patients with at least a high school degree (odds ratio [OR], 1.9), admittance to a ≥400-bed hospital (OR, 2.7), CLD (OR, 3.0), or LD (OR, 1.7) were more likely to receive treatment, whereas older patients (≥75 years) (OR, 0.5) were less likely to receive treatment. On multivariable, patients with CLD (OR, 6.8) and an excellent experience in GNC with a specialist (OR, 10.6) were more likely to receive treatment. CONCLUSIONS: HCC treatment discrepancy may be associated with patient-related factors, such as lack of specialist care (GNC), and disease-related factors, such as absence of underlying CLD.

Angiography with cone-beam CT versus contrast-enhanced MRI for living donor transplant imaging: Is MRI enough?

The purpose of this study is to compare the subjective and objective quality and confidence between conventional angiography with cone-beam computed tomography (CBCT) and magnetic resonance imaging (MRI) for the preoperative evaluation of potential donors for living donor liver transplant. Seventeen patients undergoing preoperative donor evaluation for living donor liver transplantation that underwent angiography with CBCT and contrast-enhanced MRI for evaluation of hepatic vascular anatomy were included in the study. Four attending radiologists interpreted anonymized, randomized angiography with CBCT images and MRIs, rating the diagnostic quality and confidence of their interpretation (on a 3-point scale) for each element, as well as clinically relevant measurements. Overall, the readers rated the quality of angiography with CBCT to be higher than that of MRI (median [interquartile range] = 3 (2, 3) vs. 2 (1-3), p < 0.001) across all patients. Readers of angiography with CBCT had more confidence in their interpretations as an average of all elements evaluated than the MRI readers (3 (3) vs. 3 (2, 3), p < 0.001). When the same reader interpreted both MRI and CBCT, the right hepatic artery diameter (3.8 mm ± 0.72 mm vs. 4.5 mm ± 1.2 mm, p < 0.005) and proper hepatic artery diameter (4.43 mm ± 0.98 mm vs. 5.4 mm ± 1.05 mm, p < 0.003) were significantly different between MRI and CBCT. There was poor interrater reliability for determining segment IV arterial supply for both modalities (κ < 0.2). Angiography with CBCT provides higher subjective diagnostic quality and greater radiologist confidence than MRI. The difference in measurements between CBCT and MRI when the same reader reads both studies suggests CBCT adds additional information over MRI evaluation alone.

Routine radiology-pathology concordance evaluation of CT-guided percutaneous lung biopsies increases the number of cancers identified.

BACKGROUND: Routine concordance evaluation between pathology and imaging findings was introduced for CT-guided biopsies. PURPOSE: To analyze malignancy rate in concordant, discordant, and indeterminate non-malignant results of CT-guided lung biopsies. METHODS: Concordance between pathology results and imaging findings of consecutive patients undergoing CT-guided lung biopsy between 7/1/2016 and 9/30/2021 was assessed during routine meetings by procedural radiologists. Concordant was defined as pathology consistent with imaging findings; discordant was used when pathology could not explain imaging findings; indeterminate when pathology could explain imaging findings but there was concern for malignancy. Recommendations for discordant and indeterminate were provided. All the malignant results were concordant. Pathology of repeated biopsy, surgical sample, or follow-up was considered reference standard. RESULTS: Consecutive 828 CT-guided lung biopsies were performed on 795 patients (median age 70 years, IQR 61-77), 423/828 (51%) women. On pathology, 224/828 (27%) were non-malignant. Among the non-malignant, radiology-pathology concordance determined 138/224 (62%) to be concordant with imaging findings, 54/224 (24%) discordant, and 32/224 (14%) indeterminate. When compared to the reference standard, 33/54 (61%) discordant results, 6/30 (20%) indeterminate, and 3/133 (2%) concordant were malignant. The prevalence of malignancy in the three groups was significantly different (p < 0.001). Time to diagnosis was significantly different between patients who reached the diagnosis with imaging follow-up (median 114 days, IQR 69-206) compared to repeat biopsy (33 days, IQR 18-133) (p = 0.01). CONCLUSION: Routine radiology-pathology concordance evaluation of CT-guided lung biopsy correctly identifies patients at high risk for missed diagnosis of malignancy. Repeat biopsy is the fastest method to reach diagnosis. CLINICAL RELEVANCE STATEMENT: A routine radiology-pathology concordance assessment identifies patients with non-malignant CT-guided lung biopsy result who are at greater risk of missed diagnosis of malignancy. KEY POINTS: • A routine radiology-pathology concordance evaluation of CT-guided lung biopsies classified 224 non-malignant results as concordant, discordant, or indeterminate. • The percentage of malignancy on follow-up was significantly different in concordant (2%), discordant (61%), and indeterminate (20%) (p < 0.001). • Time to definitive diagnosis was significantly shorter with repeat biopsy (33 days), compared to imaging follow-up (114 days), p = 0.01.

Evaluation of an Artificial Intelligence Chatbot for Delivery of IR Patient Education Material: A Comparison with Societal Website Content.

PURPOSE: To assess the accuracy, completeness, and readability of patient educational material produced by a machine learning model and compare the output to that provided by a societal website. MATERIALS AND METHODS: Content from the Society of Interventional Radiology Patient Center website was retrieved, categorized, and organized into discrete questions. These questions were entered into the ChatGPT platform, and the output was analyzed for word and sentence counts, readability using multiple validated scales, factual correctness, and suitability for patient education using the Patient Education Materials Assessment Tool for Printable Materials (PEMAT-P) instrument. RESULTS: A total of 21,154 words were analyzed, including 7,917 words from the website and 13,377 words representing the total output of the ChatGPT platform across 22 text passages. Compared to the societal website, output from the ChatGPT platform was longer and more difficult to read on 4 of 5 readability scales. The ChatGPT output was incorrect for 12 (11.5%) of 104 questions. When reviewed using the PEMAT-P tool, the ChatGPT content scored lower than the website material. Content from both the website and ChatGPT were significantly above the recommended fifth or sixth grade level for patient education, with a mean Flesch-Kincaid grade level of 11.1 (±1.3) for the website and 11.9 (±1.6) for the ChatGPT content. CONCLUSIONS: The ChatGPT platform may produce incomplete or inaccurate patient educational content, and providers should be familiar with the limitations of the system in its current form. Opportunities may exist to fine-tune existing large language models, which could be optimized for the delivery of patient educational content.

Technical Feasibility of Suction Thrombectomy Using a Large-Bore Aspiration System in the Portomesenteric Venous System.

PURPOSE: To assess technical feasibility and safety of portal vein thrombectomy with suction thrombectomy using a large-bore thrombectomy device for portomesenteric venous thrombosis (PMVT). MATERIALS AND METHODS: After receiving approval from institutional review board, patients undergoing PMVT treatment using a large-bore aspiration thrombectomy device (Inari FlowTriever or ClotTriever) between July 2019 and June 2021 were identified at 2 medical centers. Charts were reviewed for demographic information, imaging findings, and procedural details. PMVT was categorized using the Yerdel grading system. The thrombectomy procedure was performed via transjugular access through the existing or a new transjugular intrahepatic portosystemic shunt (TIPS) or transsplenic or transhepatic approach. Technical success was defined as successful clot reduction and restoration of portal venous flow at the conclusion of the procedure. Patient outcomes based on clinical presentation, adverse events, and thrombectomy-associated adverse events were recorded. RESULTS: Twenty patients, with a median age of 58 years (range, 23-72 years), underwent large-bore aspiration thrombectomy, which was technically successful in 19 of 20 (95%) patients. In 9 of 20 (45%) patients, 9 of 20 (45%) patients, and 2 of 20 (10%) patients, the 20-F, 16-F, and 24-F devices were used, respectively. Fourteen patients had a pre-existing TIPS, and 6 patients had a TIPS created. In 5 of 20 (25%) patients, overnight lysis was performed in conjunction with Inari thrombectomy. Thrombus resolution with restoration of flow was achieved in 19 of 20 (95%) cases. There were no thrombectomy-associated adverse events. The mean follow-up time was 70 days (±113) at which time primary patency of the portal venous system was present in 16 of 20 (80%) patients. CONCLUSIONS: Large-bore aspiration portal vein thrombectomy is feasible for PMVT.

New Frontiers in the Role of Locoregional Therapies in Breast Cancer: Proceedings from the Society of Interventional Radiology Foundation Research Consensus Panel.

Emerging evidence regarding the effectiveness of locoregional therapies (LRTs) for breast cancer has prompted investigation of the potential role of interventional radiology (IR) in the care continuum of patients with breast cancer. The Society of Interventional Radiology Foundation invited 7 key opinion leaders to develop research priorities to delineate the role of LRTs in both primary and metastatic breast cancer. The objectives of the research consensus panel were to identify knowledge gaps and opportunities pertaining to the treatment of primary and metastatic breast cancer, establish priorities for future breast cancer LRT clinical trials, and highlight lead technologies that will improve breast cancer outcomes either alone or in combination with other therapies. Potential research focus areas were proposed by individual panel members and ranked by all participants according to each focus area's overall impact. The results of this research consensus panel present the current priorities for the IR research community related to the treatment of breast cancer to investigate the clinical impact of minimally invasive therapies in the current breast cancer treatment paradigm.

Patient and Provider Perspectives of Telehealth and In-Person Interventional Radiology Clinic Visits.

PURPOSE: To assess patient and provider satisfaction with interventional radiology (IR) outpatient telehealth and in-person clinic. MATERIALS AND METHODS: This institutional review board-approved study analyzed patient satisfaction with clinic via survey after an IR outpatient telehealth or in-person visit. A physician telehealth experience survey was completed by 8 IR physicians. RESULTS: During the initial survey period, 44 (83%) of 53 patients completed a survey via telephone compared with 37 (23%) of 158 patients who were offered an electronic survey during the second survey period. Of 81 respondents, 18 (22%) were in-person and 63 (78%) were via telehealth. Of the respondents, nearly all patients (97%) in the telehealth group reported satisfaction with their telehealth clinic visit, with similar rates of high patient satisfaction between in-person and telehealth visits (P = .51). Most patients (98%) in the telehealth group strongly agreed that their physician's recommendations were clear in the telehealth visit and that their visit was private, similar to in-person visits (P = .13). A telehealth visit saved time for all patients (100%), with 78% reporting >1 hour of time-saving. All IR physicians (n = 8) reported greater efficiency with telehealth clinic than with in-person clinic and that follow-up patterns would change if telehealth was available. However, all providers (100%) found telephone visits less satisfying than in-person visits, with video visits being either equally satisfying (71%) or less satisfying (29%). CONCLUSIONS: Patient satisfaction with the in-person and telehealth outpatient IR clinic was high, with patients and providers reporting time-saving and greater efficiency with telehealth, suggesting that telehealth should remain an important component of outpatient IR clinic care.

Transjugular Intrahepatic Portosystemic Shunt and Thrombectomy (TIPS-Thrombectomy) for Symptomatic Acute Noncirrhotic Portal Vein Thrombosis.

PURPOSE: To report the safety and effectiveness of transjugular intrahepatic portosystemic shunt and mechanical thrombectomy (TIPS-thrombectomy) for symptomatic acute noncirrhotic portal vein thrombosis (NC-PVT). MATERIALS AND METHODS: Patients with acute NC-PVT who underwent TIPS-thrombectomy between 2014 and 2021 at a single academic medical center were retrospectively reviewed. Thirty-two patients were included (men, 56%; median age, 51 years [range, 39-62 years]). The causes for PVT included idiopathic (n = 12), prothrombotic disorders (n = 11), postsurgical sequelae (n = 6), pancreatitis (n = 2), and Budd-Chiari syndrome (n = 1). The indications for TIPS-thrombectomy included refractory abdominal pain (n = 14), intestinal venous ischemia (n = 9), ascites (n = 4), high-risk varices (n = 3), and variceal bleeding (n = 2). Variables studied included patient, disease, and procedure characteristics. Patients were monitored over the course of 1-year follow-up. RESULTS: Successful recanalization of occluded portal venous vessels occurred in all 32 patients (100%). Compared with pretreatment patency, recanalization with TIPS-thrombectomy resulted in an increase in patent veins (main portal vein [28% vs 97%, P < .001], superior mesenteric vein [13% vs 94%, P < .001], and splenic vein [66% vs 91%, P < .001]). Three procedure-related adverse events occurred (Society of Interventional Radiology grade 2 moderate). Hepatic encephalopathy developed in 1 (3%) of 32 patients after TIPS placement. At 1-year follow-up, return of symptoms occurred in 3 (9%) of 32 patients: (a) ascites (n = 1), (b) variceal bleeding (n = 1), and (c) intestinal venous ischemia (n = 1). The intention-to-treat 1-year portal vein and TIPS primary and secondary patency rates were 78% (25/32) and 100% (32/32), respectively. Seven patients required additional procedures, and the 1-year mortality rate was 3% (1/32). CONCLUSIONS: TIPS-thrombectomy is a safe and effective method for treating patients with symptomatic acute NC-PVT.

Evaluation of Technical Performance of Ultrasound-Guided Procedures through Hand Motion Analysis: An Exploration of Motion Metrics.

PURPOSE: To evaluate the ability of hand motion analysis using conventional and new motion metrics to differentiate between operators of varying levels of experience for central venous access (CVA) and liver biopsy (LB). MATERIALS AND METHODS: In the CVA task, 7 interventional radiologists (experts), 10 senior trainees, and 5 junior trainees performed ultrasound-guided CVA on a standardized manikin; 5 trainees were retested after 1 year. In the LB task, 4 radiologists (experts) and 7 trainees biopsied a lesion on a manikin. Conventional motion metrics (path length and task time), a refined metric (translational movements), and new metrics (rotational sum and rotational movements) were calculated. RESULTS: In the CVA task, experts outperformed trainees on all metrics (P < .02). Senior trainees required fewer rotational movements (P = .02), translational movements (P = .045), and time (P = .001) than junior trainees. Similarly, on 1-year follow-up, trainees had fewer translational (P = .02) and rotational (P = .003) movements with less task time (P = .003). The path length and rotational sum were not different between junior and senior trainees or for trainees on follow-up. Rotational and translational movements had greater area under the curve values (0.91 and 0.86, respectively) than the rotational sum (0.73) and path length (0.61). In the LB task, experts performed the task with a shorter path length (P = .04), fewer translational (P = .04) and rotational (P = .02) movements, and less time (P < .001) relative to the trainees. CONCLUSIONS: Hand motion analysis using translational and rotational movements was better at differentiating levels of experience and improvement with training than the conventional metric of path length.

Radiofrequency Ablation-Induced Tumor Growth Is Suppressed by MicroRNA-21 Inhibition in Murine Models of Intrahepatic Colorectal Carcinoma.

PURPOSE: To investigate the role of microRNA-21 (miR21) in radiofrequency (RF) ablation-induced tumor growth and whether miR21 inhibition suppresses tumorigenesis. MATERIAL AND METHODS: Standardized liver RF ablation was applied to 35 C57/BL6 mice. miR21 and target proteins pSTAT3, PDCD4, and PTEN were assayed 3 hours, 24 hours, and 3 days after ablation. Next, 53 Balb/c and 44 C57BL/6 mice received Antago-miR21 or scrambled Antago-nc control, followed by intrasplenic injection of 10,000 CT26 or MC38 colorectal tumor cells, respectively. Hepatic RF ablation or sham ablation was performed 24 hours later. Metastases were quantified and tumor microvascular density (MVD) and cellular proliferation were assessed at 14 or 21 days after the procedures, respectively. RESULTS: RF ablation significantly increased miR21 levels in plasma and hepatic tissue at 3 and 24 hours as well as target proteins at 3 days after ablation (P < .05, all comparisons). RF ablation nearly doubled tumor growth (CT26, 2.0 SD ± 1.0 fold change [fc]; MC38, 1.9 SD ± 0.9 fc) and increased MVD (CT26, 1.9 SD ± 1.0 fc; MC38, 1.5 ± 0.5 fc) and cellular proliferation (CT26, 1.7 SD ± 0.7 fc; MC38, 1.4 SD ± 0.5 fc) compared with sham ablation (P < .05, all comparisons). RF ablation-induced tumor growth was suppressed when Antago-miR21 was administered (CT26, 1.0 SD ± 0.7 fc; MC38, 0.9 SD ± 0.4 fc) (P < .01, both comparisons). Likewise, Antago-miR21 decreased MVD (CT26, 1.0 SD ± 0.3 fc; MC38, 1.0 SD ± 0.2 fc) and cellular proliferation (CT26, 0.9 SD ± 0.3 fc; MC38, 0.8 SD ± 0.3 fc) compared with baseline (P < .05, all comparisons). CONCLUSIONS: RF ablation upregulates protumorigenic miR21, which subsequently influences downstream tumor-promoting protein pathways. This effect can potentially be suppressed by specific inhibition of miR21, rendering this microRNA a pivotal and targetable driver of tumorigenesis after hepatic thermal ablation.

MR Imaging-Based In Vivo Macrophage Imaging to Monitor Immune Response after Radiofrequency Ablation of the Liver.

PURPOSE: To establish molecular magnetic resonance (MR) imaging instruments for in vivo characterization of the immune response to hepatic radiofrequency (RF) ablation using cell-specific immunoprobes. MATERIALS AND METHODS: Seventy-two C57BL/6 wild-type mice underwent standardized hepatic RF ablation (70 °C for 5 minutes) to generate a coagulation area measuring 6-7 mm in diameter. CD68+ macrophage periablational infiltration was characterized with immunohistochemistry 24 hours, 72 hours, 7 days, and 14 days after ablation (n = 24). Twenty-one mice were subjected to a dose-escalation study with either 10, 15, 30, or 60 mg/kg of rhodamine-labeled superparamagnetic iron oxide nanoparticles (SPIONs) or 2.4, 1.2, or 0.6 mg/kg of gadolinium-160 (160Gd)-labeled CD68 antibody for assessment of the optimal in vivo dose of contrast agent. MR imaging experiments included 9 mice, each receiving 10-mg/kg SPIONs to visualize phagocytes using T2∗-weighted imaging in a horizontal-bore 9.4-T MR imaging scanner, 160Gd-CD68 for T1-weighted MR imaging of macrophages, or 0.1-mmol/kg intravenous gadoterate (control group). Radiological-pathological correlation included Prussian blue staining, rhodamine immunofluorescence, imaging mass cytometry, and immunohistochemistry. RESULTS: RF ablation-induced periablational infiltration (206.92 µm ± 12.2) of CD68+ macrophages peaked at 7 days after ablation (P < .01) compared with the untreated lobe. T2∗-weighted MR imaging with SPION contrast demonstrated curvilinear T2∗ signal in the transitional zone (TZ) (186 µm ± 16.9), corresponsing to Iron Prussian blue staining. T1-weighted MR imaging with 160Gd-CD68 antibody showed curvilinear signal in the TZ (164 µm ± 3.6) corresponding to imaging mass cytometry. CONCLUSIONS: Both SPION-enhanced T2∗-weighted and 160Gd-enhanced T1-weighted MR imaging allow for in vivo monitoring of macrophages after RF ablation, demonstrating the feasibility of this model to investigate local immune responses.

Factors Associated With Complete Pathologic Necrosis of Hepatocellular Carcinoma on Explant Evaluation After Locoregional Therapy: A National Analysis Using the UNOS Database.

BACKGROUND. Complete pathologic necrosis (CPN) is associated with improved survival in patients who undergo liver transplant (LT) after locoregional therapy (LRT) for hepatocellular carcinoma (HCC). OBJECTIVE. The purpose of this article was to identify patient, HCC, and transplant center characteristics associated with rates of CPN on explant evaluation using a large national sample of patients undergoing LT after LRT for HCC measuring 3 cm or smaller. METHODS. This retrospective study used data from the United Network for Organ Sharing database. The study included 6265 adults (median age, 62 years; 1505 women, 4760 men) who underwent LT after a single type of LRT (either transarterial chemoembolization [TACE], thermal ablation, or transarterial radioembolization [TARE]) for HCCs measuring 3 cm or smaller at one of 118 U.S. transplant centers from April 12, 2012, to March 31, 2020. Patients were classified as having CPN if explant evaluation showed 100% necrosis of all HCCs. Associations with CPN were explored. Centers were categorized into tertiles on the basis of center-level CPN rates, and tertiles were compared. RESULTS. LRT was performed by TACE in 69.5% (4352/6265), thermal ablation in 19.4% (1217/6265), and TARE in 11.1% (696/6265) of patients. CPN rate was 18.5% (805/4352) after TACE, 35.8% (436/1217) after thermal ablation, 33.6% (234/696) after TARE, and 23.5% (1475/6265) overall. In multivariable analysis incorporating age, sex, model for end-stage liver disease score, α-fetoprotein level before LRT, wait list time, number of HCCs, HCC size, and the transplant center (as a random factor), use of thermal ablation (OR, 2.19; 95% CI, 1.86-2.57; p < .001) or TARE (OR, 1.92; 95% CI, 1.57-2.36; p < .001), with TACE as reference, independently predicted greater likelihood of CPN. Center-level CPN rates ranged from 0.0% to 50.0%. With centers stratified by CPN rates, ablation was performed more frequently than TACE in 5.0% of centers in the first, 15.4% in the second, and 23.1% in the third tertiles (p = .07). CONCLUSION. CPN rate on explant evaluation was low. Thermal ablation or TARE, rather than TACE, was associated with higher likelihood of CPN in patient-level and center-level analyses. CLINICAL IMPACT. Findings from this large national sample support a potential role of thermal ablation or TARE for achieving CPN of HCC measuring 3 cm or smaller.

Image-Guided Prostate Cryoablation: State-of-the-Art.

Image-guided focal therapy has increased in popularity as a treatment option for patients with primary and locally recurrent prostate cancer. This review will cover the basic indications, evaluation, treatment algorithm, and follow-up for patients undergoing image-guided ablation of the prostate. Additionally, this paper will serve as an overview of some technical approaches to cases so that physicians can familiarize themselves with working in this space. While the focus of this paper is prostate cryoablation, readers will obtain a basic literature overview of some of the additional available image-guided treatment modalities for focal prostate therapy.

Outcomes of Postprocedural Closeout Checklist Implementation to Prevent Adverse Events during Interventional Radiology Procedures: An Initiative to Improve Outcomes.

PURPOSE: To assess whether adherence to a postprocedural closeout (PPC) checklist decreases adverse events during image-guided procedures. MATERIALS AND METHODS: Based on the analysis of prior adverse events related to image-guided procedures, the Radiology Quality Committee developed a PPC checklist. The rates of serious reportable events related to image-guided procedures performed in the radiology department were recorded annually from 2015 to 2021. The rate of adverse events was normalized to the procedure volume in the corresponding periods. The number of patients requiring repeat procedures was recorded. The severity of impact was classified according to the Society of Interventional Radiology Adverse Event Classification System. The annual rates before (2015 and 2016) and after (2017-2021) the implementation of PPC were compared. RESULTS: Seventy-seven safety reports were identified in image-guided procedures over the study period, of which 43 cases were not related to the PPC, leaving 34 cases for the analysis. Radiology adverse events decreased from 0.069% (14/20,218, 7/y) before PPC implementation to 0.034% (20/58,793, 4/y) after implementation (P = .05, 43% decrease). Radiology repeat procedures decreased from 0.040% (8/20,218, 4/y) before PPC implementation to 0.007% (4/58,793, 0.8/y) after implementation (P = .0033, 80% decrease). Moreover, severity of adverse events decreased (P = .009). CONCLUSIONS: Implementation of a PPC checklist improved patient outcomes by decreasing the number of adverse events that occur from inadequate safety processes at the end of image-guided procedures by 43%, need for repeat procedures by 80%, and severity of impact of errors.