Analysis of anterior cerebral artery tortuosity: association with anterior communicating artery aneurysm rupture.

BACKGROUND: Many researchers have found correlation between tortuous arteries and development of aneurysms in cerebral arteries. However, due to our knowledge, there are no studies analysing impact of tortuosity on risk of subarachnoid haemorrhage occurrence. Therefore, we decided to determine, whether tortuosity of Anterior Cerebral Artery can be related to rupture of Anterior Communicating Artery aneurysm, as well as to severity and treatment outcome of subarachnoid haemorrhage.

METHODS: We retrospectively analyzed the Anterior Cerebral Artery anatomy of 121 patients with Anterior Communicating Artery aneurysms. From patients' medical records we obtained their history including previous and current diseases and medications. For each patient we calculated Relative Length, Sum of Angle Metrics, Triangular Index, Product of Angle Distance and Inflection Count Metrics.

RESULTS: Patients with subarachnoid hemorrhage had significantly higher Relative Length (0.70 ± 0.19 vs. 0.63 ± 0.22; p = 0.03) and significantly lower Inflection Count Metrics (0.10 ± 0.08 vs. 0.16 ± 0.19; p < 0.01). In multivariate logistic regression analysis, after adjustment of all possible confounders diabetes mellitus (OR: 0.154; 95% CI: 0.032 - 0.553; p < 0.01) and higher Inflection Count Metrics (0.604; 95% CI: 0.357 - 0.909; p = 0.042) remained independently associated with lower risk of SAH. We also found independent correlation between aneurysm dome size (R = -0.289; p = 0.02) and Triangular Index (R = 0.273; p = 0.03) and Glasgow Coma Scale score upon admission CONCLUSIONS: Higher anterior cerebral artery tortuosity might be protective factor against anterior communicating artery aneurysm rupture.