The confluence of several technologic advances has led to a significant decrease in morbidity and mortality related to aortic aneurysms. Rapid developments in diagnostic CT Angiography (CTA), advances in endovascular techniques, commercially available devices and hybrid operating rooms have happened in parallel. Similar technologic advancements in the field of augmented reality (AR) have made intraoperative navigation a possibility. AR technologies require 3D CAD file format to display patient-specific 3D data overlayed with accurate spatial positioning. Current 3D radiographic datasets are displayed using surface shaded displays limiting their use to a 2D screens. Our aim was to build an ecosystem for improved aortic segmentation, 3D CAD file generation, and AR projection of patient matched aortic segmentation via the cloud.

After IRB approval, CTA of a patient with an infrarenal abdominal aortic aneurysm requiring treatment between 2019 and 2020 was identified. The CT data was anonymized, segmented, a .STL file was created, and imported into 3-Matic Software for CAD optimization. The CAD file was exported in .OBJ file format and imported into MedReality AR system. A 3D printed model of the patient's skin surface and spine with a central viewing window to assure accuracy of AR coregistration was created using an Ultimaker 5S printer. The 3D segmented data set was then coregistered to the 3D printed model using surface fiducials as coregistration markers. Display of the 3D data sets in device neutral mobile platforms were then performed.

CTA data was segmented into 4 parts using Materialise Mimics including, skin, bone, cartilage, and arterial vasculature. The .obj file format was uploaded to MedReality platform and distributed to 4 separate devices, HoloLens 2, iPhone 12, Samsung Galaxy phone and tablet, and iPad (8th Edition). All AR devices were able to accurate display the .OBJ in spatial and non spatial Augmented reality conditions (Figure 1). The segmented 3D Data set was coregistered to the 3D printed patient model (Figure 2) demonstrating preliminary acceptable accuracy rates. MedReality cloud-based distribution system was able to deploy the data on several mobile devices simultaneously.

Integration of AR into vascular surgery has great promise. Use of cloud-based device neutral AR for patient education, treatment planning and endovascular treatment of aortic aneurysms may be paradigm to shortening a steep learning curves, reduced intraoperative radiation and improved outcomes.