RESUMEN
The surgical treatment strategy of ruptured vertebral artery dissecting aneurysm [VA-DA] is still controversial. We performed clinical and pathological studies based on a new angiographic classification aiming to guide for the surgical treatment of this disease. 19 patients with VA-DA and SAH, underwent surgery and/ autopsy, formed the subject of this study. We classified these patients, according to the longitudinal length of dilatation and narrowing [pearl and string sign] on the A-P view angiography into 3 groups: 1] small sized [>10 mm], 2] medium sized [11-20 mm], and 3] large sized [> 21 mm]. Outward appearance study was performed for 16 aneurysms during surgery and for 5 autopsy cases. The aneurysmal size [longitudinal length] was nearly the same in both the angiographic picture and the actual measurement, but it was difficult to anticipate the detailed shape of the aneurysm only from the angiographic picture. Two distinctive morphological types were revealed: lateral protrusion [saccular] and fusiform. The saccular type [4 cases] was present only in the small sized group and 3 cases treated by surgical clipping. The fusiform type was inspected in small, medium and large sized groups, but, surgical trapping [6 cases] was successful in the aneurysmal size less than 15 mm, while, operations in the aneurysmal size more than 15 mm, ended by proximal clipping [6 cases]. Histopathological Study, for 5 autopsy cases, examined the detailed pathological features of the saccular and fusiform types and speculated that dissection was localized to the base in the saccular type and to the dilated portion in the fusiform type. Also, there was only one entry point at the dilated portion in the fusiform type and these points are important for radical surgery. 1-When VA-DA with SAH is less than about 15 mm in the longitudinal length of the A-P view angiography, specially in the small sized group, surgical exploration is mandatory to explore the actual shape of the aneurysm and to decide radical treatment either by clipping or trapping. 2-In the aneurysmal size more than about 15 mm, the access to distal lesion is difficult and PICA and/or perforators usually come from the dilated portion, so proximal occlusion might be a resultant procedure and endovascular treatment may achieve the same and less invasive