Fully automatic volume segmentation using deep learning approaches to assess aneurysmal sac evolution after infrarenal endovascular aortic repair.

OBJECTIVE: Endovascular aortic repair (EVAR) surveillance relies on serial measurements of the maximal diameter despite significant inter- and intraobserver variability. Volumetric measurements are more sensitive; however, their general use has been hampered by the time required for their implementation. An innovative, fully automated software (PRAEVAorta; Nurea, Bordeaux, France), using artificial intelligence, had previously demonstrated fast and robust detection of the characteristics of infrarenal abdominal aortic aneurysms on preoperative imaging studies. In the present study, we assessed the robustness of these data on post-EVAR computed tomography (CT) scans. METHODS: We compared fully automatic and semiautomatic segmentation manually corrected by a senior surgeon (E.D.) using a dataset of 48 patients (48 early post-EVAR CT scans with 6466 slices and 101 follow-up CT scans with 13,708 slices). RESULTS: The analyses confirmed the excellent correlation of the post-EVAR volumes and surfaces and the proximal neck and maximum aneurysm diameters measured using the fully automatic and manually corrected segmentation methods (Pearson's coefficient correlation, >0.99; P < .0001). A comparison between the fully automatic and manually corrected segmentation methods revealed a mean Dice similarity coefficient of 0.950 ± 0.015, Jaccard index of 0.906 ± 0.028, sensitivity of 0.929 ± 0.028, specificity of 0.965 ± 0.016, volumetric similarity of 0.973 ± 0.018, and mean Hausdorff distance/slice of 8.7 ± 10.8 mm. The mean volumetric similarity reached 0.873 ± 0.100 for the lumen and 0.903 ± 0.091 for the thrombus. The segmentation time was nine times faster with the fully automatic method (2.5 minutes vs 22 minutes per patient with the manually corrected method; P < .0001). A preliminary analysis also demonstrated that a diameter increase of 2 mm can actually represent a >5% volume increase. CONCLUSIONS: PRAEVAorta enabled a fast, reproducible, and fully automated analysis of post-EVAR abdominal aortic aneurysm sac and neck characteristics, with a comparison between different time points. It could become a crucial adjunct for EVAR follow-up through the early detection of sac evolution, which might reduce the risk of secondary rupture.

Systematic review and updated meta-analysis of the use of drug-coated balloon angioplasty versus plain old balloon angioplasty for femoropopliteal arterial disease.

OBJECTIVE: An endovascular-first approach is usually recommended in femoropopliteal occlusive disease. However, despite high technical success, plain old balloon angioplasty (POBA) is burdened with high restenosis rates. To reduce this phenomenon, local delivery of drugs has been proposed by way of drug-coated balloons (DCBs). Our goal was to review the evidence for the use of DCBs in the management of femoropopliteal disease and to determine whether it is associated with improved outcomes compared with POBA. METHODS: Electronic searches of PubMed (MEDLINE), Embase, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, and proceedings of international conferences were performed to identify randomized controlled trials (RCTs) and observational registries evaluating the use of DCBs for femoropopliteal arterial occlusive disease. RESULTS: This meta-analysis included 13 RCTs, 6 global registries, and 3 global registries focusing on long lesions. They all used paclitaxel in the DCB arm. There was heterogeneity between trials, and the frequency of stent deployment and duration of dual antiplatelet therapy differed. At 2 years, there were significantly better outcomes for DCBs in terms of target lesion revascularization (odds ratio [OR], 0.29; 95% confidence interval [CI], 0.20-0.40), primary patency (OR, 0.38; 95% CI, 0.27-0.54), late lumen loss (mean diameter, -0.80 mm; 95% CI, -1.44 to -0.16), and Rutherford category (OR, 0.82; 95% CI, 0.57-1.19). There was no significant difference between DCBs and POBA in amputation or change in ankle-brachial index. A subgroup analysis revealed that male patients treated with DCBs performed significantly better than female patients and that diabetics, heavily calcified lesions, and popliteal lesions performed significantly worse than nondiabetics, noncalcified and mild to moderately calcified lesions, and exclusive superficial femoral artery lesions, respectively. Secondarily stented and nonpredilated lesions did not perform significantly worse, but standard-dose (3 µg/mm2) DCBs were significantly more effective than low-dose (2 µg/mm2) DCBs in reducing binary restenosis. In addition, in a low-dose DCB, the polyethylene glycol excipient performed significantly better than polysorbate and sorbitol, whereas binary restenosis was significantly less frequent with the urea excipient, associated with a standard-dose DCB, compared with the polysorbate and sorbitol excipient, associated with a low-dose DCB. CONCLUSIONS: DCB angioplasty is an effective treatment associated with high procedural success. In a meta-analysis of industry-sponsored trials, it consistently reduced late lumen loss, binary restenosis, and target lesion revascularization compared with POBA alone in the treatment of femoropopliteal disease. Further independent, non-industry-sponsored RCTs are necessary to better delineate the role of DCBs in the treatment of infrainguinal occlusive disease.

Surgical Explantation of a Fenestrated Endovascular Abdominal Aortic Aneurysm Repair Device Complicated by Aorto-Enteric Fistula.

INTRODUCTION: Alarming outcomes have been reported following infected endovascular aortic aneurysm repair (EVAR) device explantation. Infected fenestrated EVAR (FEVAR) exposes patients to even worse procedural risks. REPORT: A 67 year old man with a prior history of FEVAR presented with impaired general condition, abdominal and back pain, and increased C reactive protein. Computed tomography angiography revealed a collection around the aortic graft bifurcation and 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) revealed increased FDG uptake at this level, confirmed by labelled white blood cells, all favouring graft infection. A thoracophrenolumbotomy was performed and revealed an aorto-enteric fistula which was treated by small bowel resection. The left renal artery was transected at the distal end of the bridging stent and a thoracorenal bypass was performed. The thoracic aorta was cross clamped above the coeliac trunk for complete graft excision. Meanwhile, the right kidney was perfused with 4°C Ringer lactate solution. In situ reconstruction was accomplished with a bifurcated antimicrobial graft sutured below the superior mesenteric artery with re-implantation of the right renal artery. The patient was left with a laparostomy for definitive abdominal closure, restoration of the digestive tract, and omental wrap 72 hours later. Broad spectrum antibiotic therapy was initiated peri-operatively and reduced to sulfamethoxazole/trimethoprim for a total duration of six weeks after one sample was positive for Moraxella osloensis. Eleven months later, the patient was free from re-infection, with no fever or inflammatory syndrome. DISCUSSION: Total explantation of stent grafts with tissue debridement and post-operative antibiotic therapy is the gold standard when dealing with infected EVAR. As with type IV thoraco-abdominal aneurysm open repair, FEVAR device explantation requires additional protective measures to prevent visceral ischaemia and renal impairment. In agreement with the European Society for Vascular Surgery guidelines, such patients should be referred to dedicated vascular centres with expertise in surgical repair, anaesthetics, and post-operative intensive care.