Society of Interventional Radiology
W Monsky, R James, S Seslar, University of Washington Medical Center, Seattle, WA, University of Washington, Seattle, WA
The purpose of this study was to demonstrate feasibility of using holographic 3D Virtual Reality (VR) to visualize an angiographic catheter with electromagnetic (EM) sensors while selecting vessels in a co-registered vascular phantom. Electrophysiologists have nearly replaced angiography with EM catheter tracking. EM needle tracking is used during tumor ablation. Interventional Radiologists have not adopted this to endovascular catheters. The novel ability to visualize the catheter in coregistered dynamic VR allows one to view the 3D vascular anatomy while steering the catheter as never before possible.
A 3D hologram of the abdominal/pelvic vasculature was created from a CTA using 3D Slicer (slicer.org) and proprietary software (pyrusmedical.com). A 3D printed model of the abdominal/pelvic vasculature was held in anatomic orientation in a scaffold, for registration of the VR holographic representation to the position of the physical model in space. A Simmons 1 catheter and microcathter with EM sensors was advance in the 3D printed vascular model. A trakSTAR tracking system (Northern Digital Inc., Ontario, Canada) was used to visualize the image of the catheter in the co- registered VR displayed holographic image as mesenteric branches were selected. The right hepatic, splenic and gastroduodenal arteries were selected 6 times each using only VR guidance, then again using only fluoroscopic guidance. The time taken to steer the catheter from the common femoral artery to the target vessels was compared and also compared to times retrospectively collected from actual clinical angiographic procedures. A survey regarding VR was then completed.
The mean time to select the GDA, splenic, and right hepatic artery using VR display versus fluoroscopic guidance was 17.6, 18.6, 22.6 versus 70.3, 66.1, 73.5 seconds, respectively (P<.05). During clinical cases the mean time to select these vessels was 171.2, 92.3, 188.4 (P<.05). Survey responses suggested improved ease, precision, confidence and efficiency.
VR with EM catheter tracking enables augmented intra-procedural guidance for catheter steering with reduced radiation exposure and procedure time.