The quantity, origin, diameter and length of the PCA cortical branches were described in this review, as well as the branching pattern and the anomalies. Accordingly, the pilot study reported on these aspects. In the pilot study it was evident that the description of the branching pattern is not the "normal" pattern, since it was only observed in one case. This pattern was re-evaluated and three groups were described; monofurcation, bifurcation and trifurcation. Furthermore, one case of a fenestration was observed.

Aneurysms tend to form at branching points, thus knowledge of the branching pattern can aid in detection of ruptured and unruptured aneurysms in this region. This review outlined several gaps in the literature, and a pilot study was included to fill some of these gaps. Future research should especially focus on the branching pattern of the PCA. Possible sex, age and population differences may also exist. Keywords : Anomaly, Branching pattern, Cortical branch, Fenestration, Posterior cerebral artery