Surgical anatomy of the anterior choroidal artery: Complex morphometry and morphological analysis of its origin and relations

Background The anterior choroidal artery (AChA) and posterior communicating artery (PComA) are critical vessels with significant anatomical variations. Detailed knowledge of their morphometry and origin is essential for neurovascular surgery and understanding cerebrovascular pathology. Methods This study was conducted on 62 fresh cadavers (124 hemispheres). The external diameters of the internal carotid artery (ICA) and PComA were measured. The AChA was clas sified based on its origin: Type 1 (from the ICA), Type 2 (from the ICA bifurcation), or Type 3 (from the PComA). The distance from the AChA origin to the PComA origin was measured for each type. The circumferential origin of the AChA from the ICA was also documented. Results The mean external diameter of the ICA was 3.77±0.77 mm. The proximal, middle, and distal external diameters of the PComA were 1.01±0.49 mm, 0.97±0.48 mm, and 0.90±0.45 mm, respec tively, with a mean length of 14.82±4.74 mm. The AChA originated from the ICA (Type 1) in 76.9% of hemispheres, from the ICA bifurcation (Type 2) in 21.4%, and from the PComA (Type 3) in 1.7%. The distance between the AChA and PComA origins differed significantly between types, being greatest for Type 2 (4.73±1.16 mm) compared to Type 1 (3.98±1.23 mm) (p=0.001). The AChA most commonly arose from the posterior wall of the ICA (84.68%). Conclusion This study provides detailed morphometric data on the AChA and PComA in a Turkish/Caucasian population, revealing a notably high prevalence of the AChA originating from the ICA bifurcation. The significant difference in the AChA-PComA distance based on the origin type may have important implications for surgical planning and hemodynamic modeling, underscoring the clinical relevance of these anatomical variations.