Hypoplasia of the Posterior Communicating Artery in Japanese American Men.

Background There are many variations of the Circle of Willis (COW). The purpose of this study was to compare the prevalence at autopsy of hypoplasticity of the posterior communicating artery (PCoA) in Japanese American men to results from studies involving other ethnic groups. Methods 703 men of the Honolulu Asia-Aging Study (HAAS) were autopsied and the COW was dissected and examined. Hypoplasticity of the PCoA was recorded and compared with previous studies. Results The prevalence of hypoplastic PCoA was found to be greater in HAAS men than in other published reports. Previous studies reported hypoplasia of the PCoA ranging from 16.7% - 81% of cases. In this series, some degree of PCoA hypoplasia was observed in 85% of decedents, including 60.2% with bilateral hypoplasia. The age at death was unassociated with the severity, side, uni-laterality or bilaterality of the hypoplasia. Conclusion A high prevalence of hypoplastic PCoA was observed in this cohort. The lack of any apparent relationship with age at death suggests that brain perfusion sufficient to sustain life was not embarassed by the hypoplasia. Additional analyses will be needed to address the likely origins of the hypoplasia, and to discern any impact on parenchymal brain structure, or relationship with infarcts, hemorrhages, or atrophy. [ABSTRACT FROM AUTHOR]