gms | German Medical Science

Objective: The size of ruptured cerebral aneurysms differs significantly depending on its location. Aneurysms of the anterior circulation tend to be smaller than aneurysms of the posterior circulation. Since there is an anatomical difference in vessel diameter this study was conducted to investigate the relationship between diameter of aneurysm-carrying vessels and aneurysm size.

Methods: We retrospectively evaluated the digital subtraction angiography (DSA) of 69 patients (17 m;52 f; mean age 55.2 yrs) with ruptured cerebral aneurysms in 2009. In each angiogram the maximum diameter of the aneurysm was determined in millimeters (mm) obtained from 3D-DSA data. Vessel diameter directly adjacent to the aneurysm excluding aneurysm neck was measured in 4 single measurements to calculate a mean diameter of the aneurysm-bearing vessel. Fusiform or dissecting aneurysms were excluded in this study.

Results: Aneurysms of the anterior communicating artery (ACOM, N=21) and the middle cerebral artery (MCA, N=15) showed a significant difference in size (5.61mm vs. 7.61 mm; p=0.045) resulting in a constant ratio of vessel size to aneurysm size (VAR) of 3.28 (3.16 to 3.39) for ACOM and 4.15 (4.00 to 4.29) for MCA. Aspect ratio (ratio of aneurysm neck to aneurysm dome size and neck width) correlated significantly (p<0.01) with VAR.

Other aneurysms included posterior communicating artery (PCOM, N=13), basilar artery (BA, N=5), other aneurysms of the anterior circulation (N=5) and other aneurysms of the posterior circulation (N=6) but these did not reach statistical significance due to the small group size.

Conclusions: The present analysis demonstrated significant correlation between aneurysm-carrying vessel size and aneurysm size in ruptured ACOM and MCA aneurysms. As a consequence the results might have an impact on the decision making process for the treatment of unruptured aneurysms for the anterior cerebral circulation.