THE ANATOMICAL BASIS FOR THE CEREBELLAR INFARCTS

BACKGROUND Very little can be found in the literature concerning the v ariation of the irrigation area of the cerebellar arteries, as well as the characteristics of anastomoses among these vessels. The anatomica l features may determine certain features of cerebellar infarcts. Cons equently we examined the irrigation area of and the anastomoses among the cerebellar arteries. METHODS The anatomical features of the poster ior inferior cerebellar artery (PICA), the anterior inferior cerebella r artery (AICA), and the superior cerebellar artery (SCA) were studied in 26 cerebella injected with india ink, while their irrigation areas and anastomoses were examined in 8 of these cerebella. RESULTS The PI CA, which most often (82%) arose from the vertebral artery, was found most commonly (81.3%) to supply the largest part of the occipital surf ace of the cerebellar hemisphere, the caudal or caudomedial part of th e tentorial surface, and the inferior vermis. The AICA, which usually (92%) arose from the basilar artery, commonly (68.8%) supplied most of the petrosal surface of the hemisphere and the flocculus. The SCA, wh ich divided into the medial and the lateral trunks, always irrigated m ost of the tentorial surface of the cerebellum, the superior vermis, a nd the dentate nucleus. The PICA, AICA, and SCA were always interconne cted by anastomoses, which ranged from 40 mu m to 420 mu m in diameter . CONCLUSIONS Cerebellar infarcts were documented by computed tomograp hy (CT) or magnetic resonance imaging (MRI) examinations in 10 patient s. The infarcts were located in the PICA territory (60%) or the SCA re gion (40%). The authors compared the obtained anatomic data to the fea tures of the cerebellar infarcts in these patients.