Management of unruptured cerebral aneurysms

Abstract

A series of 62 patients treated surgically for one or several unruptured intracranial aneurysms is reported. 83 aneurysms were treated in 65 operations. The main locations of the aneurysms were: MCA 35%, ICA (posterior communicating) 22%, carotido-ophthalmic segment 12%, carotid bifurcation 11%, anterior communicating artery 11%, verterbro basilar artery 5%. The circumstances of discovery were: incidental 28%, multiple aneurysm 22%, headache 18%, ischemic episode 9%, mass effect 8%, seizures 6%. Overall, 8% of these unruptured aneurysms were certainly symptomatic, 58% were certainly asymptomatic, and for 34% the relationship with the mode of discovery was uncertain. The overall outcome of surgery was: good recovery 94%, moderately disabled 1.5%, severely disabled 1.5%, and death 3%. The post-operative complications were related to surgical technique in 2 cases, to a severe atherosclerotic state of the ICA in 1 case, and to the general arteriopathy of the patient in 1 case. The discussion reviews in the literature the various arguments developed in favor of an active treatment of the unruptured cerebral aneurysms. Three arguments are proposed. 1. The overall severity of the aneurysm rupture, with a mortality rate over 60%. 2. The cumulative risk of rupture of an unruptured aneurysm, which may be high in young patients (from 16 to 30% lifetime risk). 3. The good outcome of the surgical treatment of the unruptured aneurysm (mortality rate under 4%, morbidity rate approximately 6%). The operative risk is higher for large or giant aneurysms, for a patient with a history of ischemic cerebrovascular accident as mode of discovery, for elderly patients with arteriosclerotic thickening of ICA wall and aneurysm neck. The decision to treat or not to treat may be easier (mass-effect, multiple aneurysm, acute headache) or more difficult (chronic headache, hemorrhage of other origin, seizures, incidental discovery). The endovascular treatment with occlusion of the aneurysms sac by means of coils is more and more an alternative to surgical treatment, but requires a long follow-up to ensure the absence of reexpansion of the coil-embolized aneurysms. The screening for unruptured aneurysms, especially in cases with familial intracranial aneurysms is more and more often proposed. The authors' opinion now is surgical clipping of small and middle-sized aneurysms in young patients, without severe associated pathology, and clearly agreeing with surgery. The limit of age for surgery is usually 65 years except for those aneurysms discovered after a mass-effect. Elderly patients, giant aneurysms, patients with contra-indication for surgery, are proposed for endovascular treatment.