Preliminary Study of Morphological Variability in the Circle of Willis and Its Clinical Significance in Ethiopia: A Cadaveric Study

BACKGROUND: The Circle of Willis (COW) is a vital cerebral arterial network that maintains balanced blood flow in the brain.
Despite initial insights from Thomas Willis, recent research has highlighted its complex anatomical variations.

Objective: This study aims to evaluate the anatomical variations of the COW in Ethiopian cadavers.

METHODS: We employed a descriptive observational approach on thirty-two cadavers. Detailed morphological examinations of the
COW were performed following meticulous dissection at various Ethiopian universities.

RESULTS: Significant anatomical variations were observed, particularly in the anterior divisions of the COW, with 57.14% of cases exhibiting notable differences. Variations in the anterior communicating artery (62.5%) and anterior cerebral artery (37.5%) were particularly diverse. In the posterior segment, 66.6% of anomalies involved unilateral right hypoplastic posterior communicating arteries, and bilateral hypoplastic posterior cerebral arteries were noted in two male cadavers. Essential vessels were present in all specimens.

CONCLUSION: Comparative analysis with global studies reveals both similarities and differences, highlighting genetic and methodological influences. Recognizing these variations is crucial for diagnosing cerebrovascular diseases and managing intracranial aneurysms. Further longitudinal studies using advanced imaging techniques are recommended to enhance understanding in the Ethiopian population and beyond.

KEYWORDS: Circle of Willis, anterior cerebral artery, posterior cerebral artery, anterior communicating artery, posterior communicating artery