Cerebral saccular aneurysms represent a life-threatening condition that typically requires surgical intervention, often accomplished with a clip ligation approach across the aneurysm neck. Fluorescent angiography (FA) with indocyanine green (ICG) - a technique commonly used in neurosurgery – can be utilized to ensure that the neck of the aneurysm is fully ligated, while the adjacent vessels remain patent after clip placement. However, there is currently a lack of standardized performance test methods for surgical microscopes with FA capability. We have developed a 3D-printed, biomimetic aneurysm phantom with the potential to facilitate development and evaluation of these critical surgical instruments. Digital models of the Circle of Willis vasculature, including the multimodal imaging-based detailed anatomical (MIDA) model of the head and neck and a public domain model of a basilar tip aneurysm, were combined to generate a modular aneurysm phantom system. This system includes a basilar artery aneurysm and posterior communicator artery aneurysm phantoms. Non-fluorescent phantom components representing surrounding tissue were derived from the MIDA model. A stereolithography printer was used to create a solid vascular phantom from a custom turbid photopolymer doped with ICGsimulating dye. Feature sizes of printed components were found to be within 2.5% of digital models. Using a custom fluorescence imaging system, we were able to clearly visualize vessels and aneurysms amongst non-fluorescent background structures in the model. The methods for fabrication of a biomimetic neurovascular phantom incorporating realistic pathology have the potential to facilitate development, standardized bench testing and clinical training for intraoperative FA systems.
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