[18F]-Fludeoxyglucose Positron Emission Tomography/Computed Tomography with Radiomics Analysis in Patients Undergoing Aortic In-Situ Reconstruction with Cryopreserved Allografts.

BACKGROUND: The aim of this study was to evaluate the effectiveness of positron emission tomography/computed tomography with [18F]-fludeoxyglucose (FDG-PET/CT) and radiomics analysis in detecting differences between the native aorta and the abdominal aortic allograft after the total eradication of infection in patients undergoing infected graft removal and in situ reconstruction with cryopreserved allografts. METHODS: Between January 2008 and December 2018, 56 vascular reconstructions with allografts have been performed at our department. The present series included 12 patients undergoing abdominal aortic in situ reconstruction with cryopreserved allografts. During the follow-up, all patients underwent a total-body [18F]FDG PET/CT with subsequent radiomics analysis. In all patients, a comparative analysis between the data extracted from native aorta and cryopreserved graft for each patient was performed. RESULTS: All patients were male with a mean age of 72.8 years (range 63-84). Mean duration of follow-up was 51.3 months (range 3-120). During the follow-up, 2 patients (16.7%) needed a redo allograft-related surgical intervention. Overall, the rate of allograft dilatation was 33.3%. No patient had a redo infection during the follow-up. Radiomics analysis showed a different signature of implanted allograft and native aorta. Comparative analysis between the native aortas and cryopreserved allografts (dilated or not) showed several statistical differences for many texture features. CONCLUSIONS: The higher metabolic activity of allografts could indicate a state of immune-mediated degeneration. This theory should be proven with prospective, multicentric studies with larger sample sizes.

Definition of Proficiency Level by a Virtual Simulator as a First Step Toward a Curriculum on Fundamental Skills for Endovascular Aneurysm Repair (EVAR).

OBJECTIVE: At present, there is no proficiency-based curriculum for endovascular treatment of aortic aneurysm repair (EVAR) using virtual reality (VR) surgical simulators, whereas such curricula are available for the treatment of iliac and/or superficial femoral artery disease. The purpose of this work was to compute proficiency, defined by a benchmark level determined by the performance of experts, using a commercial VR simulator as a first step of a curriculum on EVAR. MATERIALS AND METHODS: Expert endovascular surgeons (with more than 150 EVAR cases as first operators) from 12 major Italian centers completed three cases of EVAR of increasing difficulty level 3 times each, using the Angio Mentor simulator (by Simbionix) and Gore devices. Proficiency level was based on performance of expert surgeons, as assessed by metrics from a VR simulator. RESULTS: The participating surgeons had a median of 20 years of experience and executed a median of 440 EVAR. For the 3 simulated cases, the following proficiency values were respectively obtained: total procedure time: 22 minutes 32 seconds, 23 minutes 05 seconds, and 20 minutes 32 seconds; total amount of contrast injected: 85.16 mL, 89.97 mL, and 98.01 mL total fluoroscopy time: 10 minutes 39 seconds, 12 minutes 22 seconds, and 10 minutes 17 seconds; time to contralateral gate cannulation: 5 minutes 51 seconds, 7 minutes 09 seconds, and 3 minutes 32 seconds. CONCLUSIONS: We computed proficiency levels for 3 simulated cases of EVAR using a VR simulator. Our next step is to determine whether surgical residents can reach this level. Translational research will then be required to assess the impact of such training on real patients.

Hand-assisted laparoscopic surgery versus endovascular repair in abdominal aortic aneurysm treatment.

OBJECTIVE: Hand-assisted laparoscopic surgery (HALS) for the treatment of abdominal aortic aneurysm (AAA) has shown promising initial results compared with traditional surgery, but its efficacy remains highly debated. The aim of this monocentric, retrospective study was to investigate differences in morbidity, mortality, and reintervention rates between endovascular aneurysm repair (EVAR) and HALS, in the medium- and long-term follow-up in a highly selected population. METHODS: We treated 977 patients consecutively for nonurgent AAA from January 2006 to December 2013; among them, 615 (62.9%) underwent open surgery, 173 (17.7%) HALS, and 189 (19.3%) EVAR. For this study, only patients treated with HALS or EVAR were considered. A subsequent selection process was carried out to identify the patients with clinical characteristics and aneurysm morphology amenable to either of these treatments. The final study cohort included 229 patients; 92 (40.2%) underwent HALS and 137 (69.8%) received EVAR. The two populations were homogeneous for clinical and demographic characteristics. RESULTS: The mean duration of follow-up was 57 ± 28 months (50 ± 24 months in the EVAR group and 67 ± 29 months in the HALS group; range, 2-110 months). No deaths and no statistically significant differences in severe complications or reinterventions were observed over the perioperative period (30 days). Length of stay was significantly shorter after EVAR, because the need for and length of stay in the intensive care unit were decreased. Three postoperative deaths (in-hospital mortality >30 days: HALS, 2.2%; EVAR, 0.7%; P = .7268) occurred owing to respiratory failure (two patients, one in each group) and multiorgan failure secondary to a bowel ischemia (one patient in the HALS group). Other deaths in the study population were not related to the procedure. In both groups, the major causes of death were cancer (24 cases [36.9%]), cardiovascular causes unrelated to AAA (16 [24.6%]), and chronic obstructive lung disease (10 [15.4%]). In the long-term follow-up period, there was a difference in the overall survival in favor of HALS when compared with EVAR (P = .011). CONCLUSIONS: This retrospective, single-center study shows that, within a population of similar clinical and anatomic characteristics, treatment of AAA with EVAR or HALS does not result in significant differences in early morbidity and mortality. EVAR presents significantly shorter hospital and intensive care unit length of stay, whereas HALS presents a lower aneurysm-related reintervention rate and lower perioperative cost. The strict patient selection in this trial, as is generally the case with AAA treatment, is likely the key to success for both of these techniques.