Morphological differences between the aneurysmal and normal artery in patients with internal carotid–posterior communicating artery aneurysm

The aim of this study was to identify image-based morphological parameters that correlated with the formation of internal carotid artery–posterior communicating artery (ICA–PcomA) aneurysms. Morphological parameters obtained from 3-dimensional digital subtraction angiography (3D-DSA) were evaluated from nine patients with ICA–PcomA aneurysms, including the diameter of the ICA (Dica) and PcomA (Dpcom), the angle between the ICA and the origin of the PcomA (Apcom), and the angle between the ophthalmic and communicating segments of the ICA (Aica). Measurements were performed on both sides of each patient. Parameters were analyzed with a paired-samples t-test for significance. In additional, receiver operating characteristic (ROC) analysis was performed on the significant parameter. Statistically significant differences were found between the aneurysmal (45.28 ± 29.07°) and control sides (79.22 ± 17.83°) for Apcom (p = 0.020). In the ROC analysis, the area under the curve value of Apcom was 0.852, and the threshold for optimal sensitivity and specificity was 52.25°. Therefore, the Apcom parameter was correlated with the formation of an ICA–PcomA aneurysm, and seems to be a promising morphological parameter for risk assessment of aneurysm formation.