Tentorial Branch of the Superior Cerebellar Artery with Retrograde Flow to Partially Thrombosed Large Superior Cerebellar Artery Aneurysm

Background: Although the tentorial branch of the superior cerebellar artery (SCA) was reported to be a frequent finding in living subjects in 1 study, its clinical relevance, especially in surgery for aneurysms, has not been elucidated. We present our experience with the tentorial branch of the SCA identified during surgical intervention of a distal SCA aneurysm and discuss its clinical relevance. Case Description: A 71-year-old woman presented with cerebral infarction in the SCA area, and a partially thrombosed, large, fusiform aneurysm was found in the lateral pontomesencephalic segment of the SCA. Despite trapping of the aneurysm, arterial flow was observed on postprocedural Doppler flow examination and indocyanine green angiography. Careful inspection of the area led to the identification of a small tentorial branch of the SCA as a retrograde feeder. Coagulation of the artery led to the successful completion of the trapping. Postoperatively, the patient did not develop new neurologic deficits. Conclusions: This is the first report to our knowledge of a clinical association of the tentorial branch of the SCA with a distal SCA aneurysm, which played an important role in achieving complete obliteration of the aneurysm. The recognition of this small artery is potentially important for successful cure of distal SCA aneurysms.