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It is becoming increasingly difficult to learn interventional radiology (IR) skills because there are fewer “straightforward” invasive diagnostic imaging studies, a reduction in the time available for training, concerns about patient safety, and changing patient perceptions. Computer-based simulation has the potential to allow an operator to realistically perform a virtual procedure with feedback about performance and could remove at least some of the patient’s role during the learning curve. To do this effectively requires a strategy for integrating simulator models into curricula and the development of standards for their validation. [Copyright &y& Elsevier]

A 39-year-old man with Marfan syndrome underwent replacement of the aortic valve, root, and ascending aorta for acute type A dissection. Subsequently, he underwent infrarenal aortic replacement for aortic rupture and then graft repair of a thoracoabdominal aneurysm with patch-bearing intercostals. After the third procedure, massive intraperitoneal hemorrhage required three subsequent laparotomies. CT scan showed two thoracic aortic pseudoaneurysms at the patch-graft junction that were sequentially embolized with transcatheter delivery of thrombin. [Copyright &y& Elsevier]

PURPOSE: To determine aneurysm neck diameter change after endovascular repair (EVR) of abdominal aortic aneurysm (AAA) and its relationship to stent-graft diameter. MATERIALS AND METHODS: The cases of 73 patients with AAAs who underwent EVR were reviewed retrospectively: 68 had preoperative imaging available. Neck diameter was reviewed by a single observer (M.F.B.) on preoperative, immediate postoperative, annual, and most recent contrast-enhanced computed tomographic scans. Baseline and follow-up neck diameters were compared with the manufacturers'' values for unconstrained stent-graft diameters. RESULTS: Intraobserver error was 2 mm. Aneurysm neck diameter increased from 21.8 mm (range, 17–28 mm) at baseline to 22.8 mm (range, 19–30 mm) postoperatively and 25.8 mm (range, 19–31 mm; P < .001) at a mean follow-up of 25.5 months (range, 6.2–60.8 mo). Neck diameter increase was more than 2 mm in 24 patients (33%). Mean change in the first, second, third, and fourth years was +1.63 mm, +0.52 mm, +0.25 mm, and +0.33 mm, respectively. Baseline mean stent-graft oversizing was 2.9 mm (13.7%; range, +1to +8 mm), which decreased to 0.7 mm (range, +4to +6 mm) at latest follow-up. Neck diameter exceeded stent-graft diameter (mean, 1.8 mm; range, 1–4 mm) in 21 cases (28%) and by more than 2 mm in five cases (6.8%). When neck diameter change was correlated with change in sac diameter, it was found to be insignificant (P = .24); however, it was significantly correlated with baseline oversizing (P = .01). CONCLUSIONS: After EVR, the aneurysm neck dilates, mostly in the first 2 years, by greater than 2 mm in one third of patients. This is possibly related to the presence of the endograft. The associated reduction of stent-graft oversizing warrants continued vigilance for proximal endoleak. [Copyright &y& Elsevier]

Abstract: We present a simulator for guided needle puncture procedures. Our aim is to provide an effective training tool for students in interventional radiology (IR) using actual patient data and force feedback within an immersive virtual environment (VE). Training of the visual and motor skills required in IR is an apprenticeship which still consists of close supervision using the model: (i) see one, (ii) do one, and (iii) teach one. Training in patients not only has discomfort associated with it, but provides limited access to training scenarios, and makes it difficult to train in a time efficient manner. Currently, the majority of commercial products implementing a medical VE still focus on laparoscopy where eye–hand coordination and sensation are key issues. IR procedures, however, are far more reliant on the sense of touch. Needle guidance using ultrasound or computed tomography (CT) images is also widely used. Both of these are areas that have not been fully addressed by other medical VEs. This paper provides details of how we are developing an effective needle guidance simulator. The project is a multi-disciplinary collaboration involving practising interventional radiologists and computer scientists. [Copyright &y& Elsevier]