Evaluation of the pontine perforators of the basilar artery using digital subtraction angiography in high resolution and 3D rotation technique.

BACKGROUND AND PURPOSE Compromise of perforating branches of the basilar artery resulting in brain stem infarctions has been described as a major complication of intracranial stent placement for basilar artery stenosis or after implantation of endovascular flow diverters. Descriptions of pontine arteries are mainly based on examinations of injection specimens; however, there is a lack of consistent presentation of the small branches of the basilar artery in the imaging literature. Therefore, we retrospectively analyzed DSA images and 3D rotational angiography with a review of literature for an imaging definition of microvascular anatomy of the brain stem. MATERIALS AND METHODS We retrospectively analyzed 2k DSA images (detector format 32 × 32 cm; image matrix 2480 × 1920 pixels) and 3D rotational angiography reconstructions (5 second DSA, subtraction technique) obtained on Axiom Artis zee biplane neuroradiologic angiography equipment using standard protocol. RESULTS On 2D and 3D DSA images, small arterial side branches of the basilar artery can be demonstrated in each of the cases but with a wide variation in the visibility of these vessels. Compared with 2D DSA images, 3D DSA reconstructions allow superior visualization of the small branches of the basilar artery. CONCLUSIONS Our results demonstrate that 2D DSA and 3D-rotation techniques are able to reliably visualize the penetrating branches of the brain stem in vivo. No zone of basilar artery is free from important side branches. Collateral pathways between circumferential and perforating arteries are occasionally detectable. In the future, further refinement of imaging techniques is necessary to increase the reliability of small vessel angiography to use this data for risk assessment before stent placement and aneurysm treatment.