Morphometry and anatomical variations of posterior cerebral artery in northeast Brazil

Background: The posterior cerebral artery (PCA) is a vessel of the Circle of Willis. Variations are observed in the first segments of the PCA and its branches, especially in the thalamoperforating arteries (TPAs) and in the artery of Percheron (AP). Anatomical presentation of these arteries is of relevant clinical importance for safer neurosurgical approaches. Objective: To identify the most frequent PCA and TPA patterns and the morphometry of P1 and P2 branches in human brains from the Northeastern region of Brazil. Methods: Specimens of human cadavers from Northeast Brazil were isolated. PCAmorphology, TPAs classification and prevalence of APwere evaluated. The length and diameter of the P1 and P2 segments of the PCA were measured. Values of p <0.05 were considered significant. Results: The adult pattern was the most frequent. There were two (22.22%) cases of unilateral PCA trifurcation. No vascular fenestration or bifurcation was found. The type of TPA was mainly bilateral multiple (36,3%). The prevalence of AP was 18,2%. No differences were observed between the right and left sides in themorphometric variables (p> 0.05). Conclusion: In this study, the adult pattern of PCA was the most frequent and trifurcation of PCA, a rare anomaly, was found in 22,2% of specimens. TPAsweremostly bilateral multiple type. No differences between sides in the length and diameter of the segments P1 and P2 were found. These data can contribute to safer approaches to neurological pathologies in this population in Northeast Brazil.