Recurrent Stenoses in Arteriovenous Fistula (AVF) for Dialysis Access: cuttIng ballooN angioplaSTy combined wITh paclitaxel drUg-coaTed balloon angioplasty, an observatIONal study (INSTITUTION Study).

PURPOSE: To study the safety and efficacy of cutting balloon angioplasty (CBA) followed by paclitaxel drug-coated balloon (PCB) angioplasty for recurrent venous lesions in arteriovenous fistulas (AVFs). MATERIALS AND METHODS: We conducted a prospective single-arm cohort study of CBA followed by PCB angioplasty for recurrent AVF stenoses between September 2017 and April 2019. In total, 44 participants were recruited. Target lesions were included if they had recurred within 12 months post-angioplasty, were > = 0.5 cm upstream from the arteriovenous anastomosis, and did not involve the central veins. Up to two non-target lesions per circuit/participant with the same definition were allowed. Lesions were considered separate when there was an intervening 2-cm segment of normal vessel. Technical success was defined as complete lesion effacement on angioplasty. End-points of target and circuit patency were evaluated clinically at 3, 6, and 12 months post-procedure. RESULT: Technical success was 96% (42/44): Two participants were excluded from analysis due to the need for high-pressure balloon angioplasty as the target lesions did not efface with CBA. The median follow-up duration was 337.5 days. Mean stenosis pre- and post-angioplasty was 69.0% (51.6-84.8) and 20.8% (0-44.8), respectively. The target lesion primary, primary assisted and circuit patency for the entire study population (n = 42) were 61.6 ± 7.8%, 92.7 ± 4.0%, and 54.7 ± 7.9%, respectively, at 12 months. For participants without non-target lesions (n = 22), the rates were 77.3 ± 8.9%, 90.9 ± 6.1%, and 60.7 ± 11.0%, respectively, at 12 months. CONCLUSION: CBA followed by PCB angioplasty appears safe and feasible for treatment of recurrent venous lesions in dysfunctional AVFs.

Review of Junior Resident Plain Film Reporting and Audit in Singapore.

BACKGROUND: Graduate medical education in Singapore recently underwent significant restructuring, leading to the accreditation of residency programs by the Accreditation Council for Graduate Medical Education-International (ACGME-I). In radiology, this involved a change in teaching and quality assurance of plain film (PF) reporting. PF reported by junior residents (postgraduate year 1-3) are subject to a 50% random audit. To date, national data on junior resident performance in PF reporting have not been published. OBJECTIVE: We reviewed performance in PF reporting under the current teaching and audit framework. METHODS: Retrospective review of junior resident reported PF audit data from all 3 radiology residency programs in Singapore. The number of residents audited, number of PF reported and audited, and major discrepancy rates were analyzed. RESULTS: On average, 86 440 PF were audited annually nationwide from an estimated 184 288 junior resident-reported PF. Each program trained between 4 to 24 junior residents annually (mean 15), averaging about 44 each year nationwide. A mean of 28 813 PF were audited annually in each program (range 4355-50 880). An estimated mean of 4148 PF (range 1452-9752) were reported per junior resident per year, about 346 PF per month. The major discrepancy rate ranged from 0.04% to 1.13% (mean 0.34%). One resident required remediation in the study period. CONCLUSIONS: Structured residency training in Singapore has produced a high level of junior resident competency in PF interpretation.

Recanalisation of an axillary vein occlusion jailed by a migrated cephalic arch stent-graft using the TruePath chronic total occlusion drilling device.

BACKGROUND: Stent placement in the cephalic arch is being used with increasing frequency. Late complications of bare metal and stent grafts in dialysis access, in particular stent migration, are often under-reported and can lead to compromise of future dialysis circuits. CASE PRESENTATION: A 52-year-old man developed acute arm swelling 2 days after creation of a left arm brachio-basilic arteriovenous graft. The axillary vein was found to be jailed by a previously deployed cephalic arch stent graft which had migrated into the subclavian vein. There was failure to cross through the fabric of the stent graft using conventional chronic total occlusion wires and techniques. A TruePath device was used successfully to cross through the fabric of migrated cephalic arch stent graft and recanalise the short subclavian-axillary vein occlusion. CONCLUSION: The adapted use of a drilling chronic total occlusion device to drill through the fabric of migrated stent graft was performed successfully to allow complete recanalisation of the occluded axillary vein.

Catheter-Directed Computed Tomography Hepatic Angiography for Yttrium-90 Selective Internal Radiotherapy of Hepatocellular Carcinoma Reduces Prophylactic Embolization of Extrahepatic Vessels.

OBJECTIVES: To determine the rate of prophylactic embolization of extrahepatic vessels in patients undergoing yttrium-90 selective internal radiotherapy (90Y SIRT) for hepatocellular carcinoma (HCC) with the use of catheter-directed computed tomography hepatic angiography (CD-CTHA). MATERIALS AND METHODS: This retrospective study included 186 HCC patients who received 90Y SIRT from May 2010 to June 2015 in a single institution. All procedures were performed in a hybrid angiography-CT suite equipped with digital subtraction angiography (DSA) and CD-CTHA capabilities. CD-CTHA was performed during pre-treatment hepatic angiography. 90Y SIRT was administered approximately 2 weeks later. Selective prophylactic embolization of extrahepatic vessels was performed if extrahepatic enhancement was seen on CD-CTHA or if an extrahepatic vessel opacified on DSA/CD-CTHA despite the final microcatheter position for 90Y microsphere delivery being beyond the origin of this vessel. RESULTS: Thirty-five patients (18.8%) required selective embolization of extrahepatic vessels. Technical success of 90Y SIRT was 99.5%. Two patients (1.1%) developed radiation-induced gastrointestinal ulceration, and one (0.54%) developed radiation-induced pneumonitis. Extrahepatic uptake of 90Y microspheres was seen in the gallbladder of one patient without significant complications. CONCLUSION: The use of CD-CTHA in 90Y SIRT of HCC was associated with a low rate of prophylactic embolization of extrahepatic vessels while maintaining a high technical success rate of treatment and low rate of complications. LEVEL OF EVIDENCE: Level 4, case series.

Hemodialysis Arteriovenous Fistula and Graft Stenoses: Randomized Trial Comparing Drug-eluting Balloon Angioplasty with Conventional Angioplasty.

Purpose To compare lesion primary patency and restenosis rates between drug-eluting balloon (DEB) percutaneous transluminal angioplasty (PTA) and conventional balloon PTA (cPTA) in the treatment of arteriovenous fistula (AVF) and arteriovenous graft (AVG) stenosis. Materials and Methods In this prospective study, 119 participants (mean age, 59.2 years; 79 men, 40 women) with failing AVFs (n = 98) or AVGs (n = 21) were randomly assigned to undergo either DEB PTA (n = 59) or cPTA (n = 60) from January 2012 to May 2013. Primary end points were lesion primary patency and restenosis rates at 6 months; secondary outcomes were anatomic and clinical success after PTA, circuit primary patency at 6 months and 1 year, and lesion primary patency at 1 year. Statistical analysis was performed by using the Kaplan-Meier product limit estimator, and hazard ratio was calculated by using Cox proportional hazards regression. Complication rates were assessed in both groups. Results Estimated lesion primary patency in the DEB PTA and cPTA arms was 0.81 and 0.61, respectively, at 6 months (P = .03) and 0.51 and 0.34, respectively, at 1 year (P = .04). Estimated circuit primary patency in the DEB PTA and cPTA arms was 0.76 and 0.56, respectively, at 6 months (P = .048) and 0.45 and 0.32, respectively, at 1 year (P = .16). Restenosis rate was 34.0% (16 of 47) for DEB PTA and 62.9% (22 of 35) for cPTA at 6 months (P = .01). No major complications were noted. Conclusion Drug-eluting balloon angioplasty was effective in prolonging lesion primary patency of dialysis access stenoses at 6 months and 1 year. © RSNA, 2018.

Phantom Study Investigating the Accuracy of Manual and Automatic Image Fusion with the GE Logiq E9: Implications for use in Percutaneous Liver Interventions.

PURPOSE: To determine the accuracy of automatic and manual co-registration methods for image fusion of three-dimensional computed tomography (CT) with real-time ultrasonography (US) for image-guided liver interventions. MATERIALS AND METHODS: CT images of a skills phantom with liver lesions were acquired and co-registered to US using GE Logiq E9 navigation software. Manual co-registration was compared to automatic and semiautomatic co-registration using an active tracker. Also, manual point registration was compared to plane registration with and without an additional translation point. Finally, comparison was made between manual and automatic selection of reference points. In each experiment, accuracy of the co-registration method was determined by measurement of the residual displacement in phantom lesions by two independent observers. RESULTS: Mean displacements for a superficial and deep liver lesion were comparable after manual and semiautomatic co-registration: 2.4 and 2.0 mm versus 2.0 and 2.5 mm, respectively. Both methods were significantly better than automatic co-registration: 5.9 and 5.2 mm residual displacement (p < 0.001; p < 0.01). The accuracy of manual point registration was higher than that of plane registration, the latter being heavily dependent on accurate matching of axial CT and US images by the operator. Automatic reference point selection resulted in significantly lower registration accuracy compared to manual point selection despite lower root-mean-square deviation (RMSD) values. CONCLUSION: The accuracy of manual and semiautomatic co-registration is better than that of automatic co-registration. For manual co-registration using a plane, choosing the correct plane orientation is an essential first step in the registration process. Automatic reference point selection based on RMSD values is error-prone.