2nd Place Co-Winner: Joshua Wong – C. Frank Webber Prize Competition
ABSTRACT
Early Feasibility of Intra-Operative Positioning System (IOPS) ex vivo experience with Endovascular Aortic Repair (EVAR)
| JOSHUA WONG | McGovern Medical School at UTHealth |
Class of 2025 |
| Sponsored by: | Dr. Gustavo Oderich |
| Supported by: | Department of Cardiothoracic and Vascular Surgery |
| Key Words: | Vascular Surgery, Endovascular, Aortic Repair, EVAR |
Objective: To describe the early feasibility of a novel GPS-like surgical navigation system for EVAR procedures using a 3D-printed infrarenal aneurysmal aorta model
Methods: IOPS (Centerline Biomedical, Cleveland, OH, USA) is an FDA-approved endovascular navigation system that minimizes the dependence on fluoroscopy by using preoperative computed tomography angiography (CTA) to construct a live 3D view during endovascular interventions.
We designed and built a 3D-printed abdominal aortic aneurysmal model based on human anatomical vessel sizes (Figure 1). The model was fabricated from a thermoplastic polyurethane powder using selective laser sintering. The experiment was performed in a hybrid operating room (GE Allia IGS 7) on a free-floating angiography table (Figure 2). Continuous physiologic volumetric flow was supplied by a 7000 MDX flow pump (Sarns Inc/3M, Ann Arbor, MI USA) connected to the proximal descending thoracic aorta of the 3D model. Outflow of the system was through visceral vessels and bilateral iliac arteries. The flow rate of the pump was set to 5L/min with the mean arterial pressure within normal physiologic range throughout the entire EVAR simulation and was performed under fluoroscopy using the hybrid angiography system. Digital subtraction angiographies were performed using a power injector or manual injection.
We observed the learning curve of five participants with varying degrees of endovascular experience using three different approaches for gate cannulation. The three different approaches were standard fluoroscopic guidance and IOPS full-screen guidance with and without HoloLens 2 (Microsoft, Redmond, Washington, USA). IOPS full-screen guidance utilized the IOPS technology with real-time 3D multi-view display. IOPS HoloLens 2 guidance projected IOPS technology through the HoloLens, where the operator can see their hand manipulations and the real-time 3D catheter and wire orientation simultaneously. For each IOPS trial, the participant had the option to utilize fluoroscopy if there was difficulty cannulating with IOPS guidance alone. Each approach was conducted three times per participant.
Results: There appeared to be a learning curve with all three approaches. The third trial of each approach was completed faster than all respective first trials (Figure 3). Additionally, the IOPS approaches had less fluoroscopy time than fluoroscopic guidance alone (Figure 4). In fact, by the second trial of each IOPS approach (both full-screen and HoloLens) all participants had a fluoroscopy time of 0, suggesting that they felt comfortable using IOPS technology alone. Comparing the final trial of all three approaches, the IOPS HoloLens guidance had the shortest median gate cannulation time with 78 seconds and fluoroscopic guidance being the longest with 160 seconds. Three out of the five participants had the longest median gate cannulation duration using fluoroscopic guidance and the shortest median gate cannulation during using IOPS HoloLens (Figure 5). The most experienced participant followed this trend with a median fluoroscopic guidance duration of 115 seconds, median IOPS full-screen duration of 78 seconds and median IOPS HoloLens duration of 56 seconds.
Conclusion: This early feasibility study demonstrates successful utilization of IOPS guidance during endovascular cannulation and an achievable learning curve across various experience levels. Other models with different anatomical conditions are needed to continue evaluation and feasibility of IOPS.