Computer-Assisted Visualization of Arteriovenous Malformations on the Home PC

OBJECTIVE: Arteriovenous malformations (AVMs) are difficult lesions partly because it is difficult to formulate a mental, 3D image of the nidus and of its supplying arteries, draining veins, and arteries of passage. Our purpose is to provide PC software that allows better visualization of complex, three-dimensional (3D), connected vascular anatomy for surgical planning. METHODS: Vessels are defined from magnetic resonance angiograms (MRA) and are symbolically linked to form vascular trees. The nidus of the AVM is also defined from MRA. These representations of the nidus and vasculature can be viewed together in a program that allows the user to color-code groups of vessels, or to selectively turn connected groups of vessels “off” to avoid obscuration. Structures can be viewed from any angle. The vessels can also be shown intersecting any MRA slice or superimposed upon digital subtraction angiograms obtained from the same patient. RESULTS: We show results from 2 AVM cases in which our representations were compared to the findings at surgery. Our 3D vascular trees correctly depicted the relationship of the nidus to feeding vessels in 3D. We show an additional, unoperated case in which vessel trees were created from 3D-DSA data and compared to a volume rendering of the original dataset. CONCLUSIONS: Computer-assisted, 3D visualizations of complex vascular anatomy can be helpful for planning the surgical excision of AVMs. Such programs can provide important information difficult to obtain by traditional techniques. The approach is also applicable to guidance of endovascular procedures and removal of complex tumors.