However — an MRI spot sign, huh…
Magic 1.2F / Hybrid .07
Discussion: The collicular/qudrigeminal plate supply is shared between PCA and SCA. The former is usually via the Collicular Artery, which also supplies the cerebral peduncle. It has a typical course parallel to the PCA — and thus is dangerous — one can get into it during stroke or other interventions and think one is in the PCA — that can be really bad. Proximal occlusions usually result in paralysis because of the peduncle. Another supplier of tectum is the posterior medial choroidal. From SCA, supply will come from the superior vermian branch. Venous drainage of tectal plate is classically into the Precentral Cerebellar Vein — an unpaired vein of much historical importance, since its shifts were indicative of location for different masses.
In this case there is trace supply via SCA and mostly from unilateral collicular — allowing for very nice targeted nBCA closure.