Role of patient-specific virtual reality rehearsal in carotid artery stenting.

BACKGROUND: Recent advances in simulation science permit patient-specific rehearsal of endovascular stenting procedures. This study aimed to evaluate how effectively real interventions are replicated by patient-specific rehearsal technology, and to assess its value as a preparatory tool for the interventionalist and the operating team. METHODS: All patients deemed candidates for carotid artery stenting procedures with suitable computed tomography images were enrolled. Each team member rehearsed the virtual procedure in the laboratory, simulated operating theatre or angiography suite environment immediately before treating the real patient. Dexterity and qualitative metrics were recorded. Subjective questionnaires used a Likert scale from 1 (poor) to 5 (excellent). RESULTS: Of 18 patients, three were excluded. In 11 of 15 and 13 of 15 patients respectively endovascular tool use and fluoroscopy angles were identical during rehearsal and the real procedure. In a third of patients, the simulator did not adequately predict difficulties in cannulating the stenotic internal or common carotid arteries. The procedure realism, value in evaluating the case, increase in efficiency in tool use, and potential to increase communication, confidence and team performance were all rated highly (4 of 5). CONCLUSION: Patient-specific rehearsal was rated highly for both face and content validity. Access strategy, endovascular material use and angiographic imaging were all replicated effectively, although certain biomechanical vessel properties seemed to be replicated to a lesser degree. Patient-specific rehearsal constitutes a unique tool that may help tailor endovascular material choice, and optimize the preoperative preparation of the interventionalist and team.

Patient-specific endovascular simulation influences interventionalists performing carotid artery stenting procedures.

OBJECTIVE: The ability to perform patient-specific simulated rehearsal of complex endovascular interventions is a technological advance with potential benefits to patient outcomes. This study aimed to evaluate whether patient-specific rehearsal of a carotid artery stenting (CAS) procedure has an influence on tool selection and the use of fluoroscopy. METHODS: Following case note and computed tomography (CT) angiographic review of a real patient case, subjects performed the CAS procedure on a virtual reality simulator. Endovascular tool requirements and fluoroscopic angles were evaluated with a pre- and post-case questionnaire. Participants also rated the simulation from 1 (poor) to 5 (excellent). RESULTS: Thirty-three endovascular physicians with varying degrees of CAS experience were recruited: inexperienced (5-20 CAS procedures) n = 11, moderately (21-50 CAS procedures) n = 7 or highly experienced (>50 CAS procedures) n = 15. For all participants, 96 of a possible 363 changes (26%) were observed from pre- to post-case questionnaires. This was most notable for optimal fluoroscopy C-arm position 15/33 (46%), choice of selective catheter 13/33 (39%), choice of sheath or guiding catheter 11/33 (33%) and balloon dilatation strategy 10/33 (30%). Experience with the CAS procedure did not influence the degree of change significantly (p > 0.05), and all groups exhibited a considerable modification in tool and fluoroscopy preference. The model was considered realistic and useful as a tool to practice a real case (median score 4/5). CONCLUSION: Patient-specific simulated rehearsal of a complex endovascular procedure strongly influences tool selection and fluoroscopy preferences for the real case. Further research has to evaluate how this technology may transfer from in vitro to in vivo and if it can reduce the radiation dose and the number of endovascular tools used and improve outcomes for patients in the clinical setting.

Patient-specific simulation for endovascular procedures: qualitative evaluation of the development process.

BACKGROUND: Recent advancements in simulation permit patient-specific rehearsal of carotid artery stenting procedures. This study evaluates the feasibility of transferring patient-specific CT data into the simulator, creating a 3D reconstruction and performing a rehearsal. The face validity of the model was assessed. METHODS/RESULTS: By thematic analysis of qualitative data, an algorithm was generated, focusing on simulation set-up, time of data transfer, software/compatibility issues and problem-solving strategies. The face validity of the simulated case was evaluated by 15 expert interventionalists: realism (median 4/5), training potential (median 4/5) and pre-procedure rehearsal potential for challenging CAS cases (median 4/5) were rated highly. CONCLUSIONS: Setting up a procedure rehearsal is feasible and reproducible for different patients in different hospital settings without major software compatibility issues. The time to create a 3D reconstruction of patient-specific CT data is a major factor in the total time necessary to set up a rehearsal. The face validity is highly rated by experts.

Harlequin syndrome: two new cases and a management proposal.

The Harlequin syndrome is a rare autonomic disorder, characterized by unilateral diminished sweating and flushing of the face in response to heat or exercise. We present two new cases and evaluate the data of 83 patients described in the literature. We provide diagnostic and therapeutic guidelines.

A case of a spontaneous popliteal arteriovenous fistula.

This case report describes a 69-year-old female diagnosed with a spontaneous popliteal arteriovenous fistula of the right leg. Some deliberation is given on the aetiology of this rare condition as well as a description of the diagnostic and therapeutic options for fistula of the popliteal artery in general.