ANATOMICAL AND MORPHOLOGICAL FACTORS CORRELATING WITH RUPTURE OF INTRACRANIAL ANEURYSMS IN PATIENTS REFERRED FOR ENDOVASCULAR TREATMENT

The size of intracranial aneurysms is the only characteristic shown to correlate with their rupture. However, the critical size for rupture has varied considerably among previous accounts and remains a point of controversy. Our goal was to identify statistically significant clini cal and morphological factors predictive of the occurrence of rupture and aneurysm size in patients referred for endovascular treatment. We retrospectively recorded the following factors from 74 patients who pr esented with ruptured (40) or unruptured (34) aneurysms: aneurysm morp hology (uni/multilobulated), location (anterior/posterior), maximum di ameter, diameter of the neck, and the patient's age and sex. We perfor med stepwise discriminant, and stepwise and logistic regression analys is to identify factors predicting rupture and the size of the aneurysm at rupture. The mean diameter of the ruptured aneurysms was 11.9 +/- 6.3 mm, range 3.0-33.0 mm, and that of the unruptured aneurysm 13.5 +/ - 5.8 mm, range 5.0-30 mm. Stepwise discriminant analysis identified a neurysm morphology (P < 0.001) and location in the intracranial circul ation (P < 0.001) as statistically significant factors in predicting r upture. Stepwise regression analysis revealed that aneurysm morphology and the size of the neck were predictors of aneurysm size at rupture.