Professor Neurosurgery, Ansan Hospital, Korea University Medical Center
Introduction: Although previous studies have investigated the predictors of posterior communicating artery (PCoA) aneurysm rupture with clinical and radiologic parameters, the accessibility of “small PCoA aneurysms ( < 5mm)” has rarely been reported. Here, we designed a study to identify the factors which are thought to be risky and prone to rupture in small PCoA aneurysms ( < 5mm).
Methods: A total of 114 patients diagnosed with PCoA aneurysm under 5mm in size on digital subtraction angiography were retrospectively enrolled and divided into ruptured (n=51) and unruptured (n=63) groups. Clinical variables were reviewed, and 10 radiologic parameters were obtained, including maximum diameter, height, width, neck width, aspect ratio, dome-to-neck ratio, bleb formation, size ratio, presence of fetal-type PCoA, and inflow angle. Statistical analyses were conducted to compare the groups (ruptured vs unruptured) and identify the risk factors for rupture.
Results: High rupture rate of small PCoA aneurysm is noted (51/114, 44.7%). In the comparison analysis, parameters of size ratio (P=.045), aspect ratio (P=.001), and bleb formation (P=.015) were significantly different between the 2 groups. In the regression model, the aspect ratio (P=.045) and bleb formation (P=.004) were significantly associated with the rupture of aneurysm.
Conclusion : In respect of small ( < 5mm) PCoA aneurysms of our cohort, morphologic parameters of “bleb formation” and “a high aspect ratio” are present more often in ruptured aneurysms as compared to unruptured aneurysms.
