Comparative analysis of the animal model and results of the clinical research of the aneurysm inclination angle as the predisposing factor for the occurrence of rupture.

Introduction: Natural course of aneurysms that occur on blood vessels of the brain singles out the need for understanding the mechanism of the occurrence of aneurysm wall rupture and identification of anatomic characteristics as predictive factors for hemorrhage to occur.

Objective: In this study we comparatively present results of our researches and experimental models on animals.

Methods: We made a comparative analysis of anatomical characteristics of blood vessels of the brain and aneurysms obtained on the basis of digital subtraction angiography and intraoperative finding. In this article we review recent research in the anatomic characteristics of intracranial aneurysms and parent blood vessels. We present a series of 185 aneurysms (ruptured and unruptured) dissected at the Neurosurgical Clinic of Clinical Center of Serbia in Belgrade.

Results: Inclination angle may be considered as the vital predesposing factor for intracranial aneurysm rupture. In aneurysms that ruptured it was 139.748+/-27.242 degrees, while in unruptured aneurysms it was considerably smaller and amounted to 100.882+/-22.001 degrees (p<0.01).

Conclusion: Inclination angle may be regarded as the vital predisposing factor since it differs considerably in unruptured and ruptured aneurysms. Aneurysms with blood stream angle smaller than 115 degrees have very small probability of rupture, while blood stream angle bigger than 150 degrees presents a high risk of rupture.