Over a period of 10 years (1990 - 1999) 472 surgical operations in 443 patients were performed and 611 aneurysms (AN) were treated at the Dept. Neurosurgery Ústí nad Labem and later at Dept. Neurosurgery, Charles Univ. ÚVN Střešovice. Peak age of patients quinquagenarians, females slightly prevailed. 50 % patients were treated within 3 days after their subarachnoid haemorrhage (SAH), 75 % within 10 days. Multiple AN were seen in 25 % of patients. There was a total of 81 unruptured AN, 277 surgical operations in patients in Hunt and Hess (HH) grade I-III, and 114 patients in HH IV-V. 70 % AN were at 3 typical sites (anterior communicating artery complex, posterior communicating artery and middle cerebral artery bifurcation), nearly 10 % of AN were in the vertebrobasilar area. Basic motto of management was acute surgery as soon as possible irespective of time and patients status. Only patients with destruction of vítal strnctures were not operated. Over a 10 -year period the authors lost 2 patients due to re-rnpture prior to surgery. The overall morbidity mortality rate (MM) was 19.3 %. The results from the last 2 years were evaluated separately. These resemble those of the whole series with the only exception in patients HH I-III, where the MM was 3.1 % in 1998 - 1999 as compared with the all series MM in this group which was 9 %. Technically 92.4 % of AN were eliminated by clipping, with the use of other techniques (trapping, parem artery occlusion), surgery was successful in 95 %. In the postoperative follow-up 2 patients presented with rupture of de novo AN (0.42 %). Conclusions. With the development of neurointerventional techniques the presented series mut be considered a historical one. SAH is a neurosurgical emergency and AN should be excluded from circulation as soon as possible, hnal result is determined predominantly by the initial bleeding with an assumed MM of 17 - 20 % in a surgically treated group. The best results can be expected in early surgery in good grade patients (MM 3 - 5 %). The technical success rate and long-term durability of clipping is approximately 95 %.

        Key words: aneurysm, surgery, subarachnoid haemorrhage