P-030 Voxel-based calculations of intrasaccular aneurysm and device volume fill

Abstract

Introduction Various embolization techniques are available for intracranial aneurysms. The precise volume measurement of an aneurysm sac can help improve embolization techniques, such as: coils, liquid embolics, flow disruptors, and flow diverters. Aneurysm sizing and volumetric information help interventionalists assess flow and stability pre-treatment and potential remnant or recanalization risks post-treatment. Materials and Methods This research project applies voxelbased volume calculations, from CT or MRI medical imaging data, to determine accurate 3-D aneurysm volume calculations. Additionally, the application can display clinically relevant parameters, such as aneurysm neck diameter, dome height and midline-dome width (for dome:neck (D:N) ratio calculations). To develop the measurement techniques, wide-neck canine aneurysm models (n=10) were scanned with a Siemens Inveon Micro-CT scanner (University of Arizona TBIR, Tucson, AZ) and analyzed with InVesalius 3.0 software (Ministry of Health, Brazil). The software loads the imaging data, discretizes the intrasaccular aneurysm, separating the device volume from the aneurysm sac. This data was compared to physical measurements of excised aneurysms and calibrated 2-D angiographic images. Results Invesalius image processing techniques helped determine the domain of aneurysms with less than 5% volumetric error, when compared to measurements recorded during the aneurysm creation surgery. Current measurement techniques in 2-D planes have errors as high as 30%. This technique helps determine the macroscopic properties of aneurysms, as well as the volumes of abnormal aneurysm shapes. The software was also used to measure% fill of a liquid embolic (NeuroCURE) delivered to the 10 canine aneurysms. In all 10 cases the precise delivery of NeuroCURE resulted in 90100% aneurysm sac filling, versus < 30% for traditional coiling techniques. Conclusion As new aneurysm treatment devices are developed and greater% fill of the aneurysm sac is attempted, the need for precise aneurysm volume calculations will be of high priority. This project brings together clinical and engineering expertise to translate medical imaging data directly into volumetric measurements with highly precise calculations that are currently not available from 2-D angiographic images. Measuring the size and dimensional properties of aneurysms with voxel-based volume calculations provides a fast, reliable and repeatable resource for aneurysm assessment. This technique will help interventionalists appropriately assess risk and treatment options for a broad range of aneurysm morphologies. Disclosures S. Schwartz: 1; C; 5R42NS097069-03 (NIH Grant#)). B. Fennell: 1; C; 5R42NS097069-03 (NIH Grant #). C. Settanni: 1; C; 5R42NS097069-03 (NIH Grant #). N. Norris: 1; C; 5R42NS097069-03 (NIH Grant #). T. Becker: 1; C; 5R42NS097069-03 (NIH Grant #).