Unruptured aneurysms associated with ischaemic cerebrovascular diseases. Surgical indication.

Out of 3435 patients with ischaemic cerebrovascular disease 2540 cases were investigated using cerebral angiography. In 127 of them (5%) aneurysms were found, but without clinical evidence of subarachnoid haemorrhage (SAH). 45 cases were operated upon and 82 were treated conservatively. Five of these 82 cases (6%) suffered from SAH 3 months to 10 years (mean interval 5.6 years) after the angiographic diagnosis. Four of these 5 patients with SAH died. Among the 45 surgical cases follow-up was uneventful in 29 (64%). The other 16 cases postoperatively showed neurological deterioration (36%), which was transient in 6 but with only minor improvement in 10. Of these 10 cases 2 died from cerebral infarction related to intra-operative temporary vascular occlusion respectively myocardial infarction. Thus surgical mortality was 4% and permanent morbidity 18%. Causes of postoperative neurological deterioration were partly related to general arteriosclerotic changes and special fragility of the ischaemic brain, and partly to operative technique (excessive brain retraction, damage to cortical veins, occlusion of major vessels or damage to perforators, temporary artery occlusion). Apparently in cases with ischaemic cerebrovascular diseases operative procedures, which in other cases as a rule are well tolerated, may produce harmful effects. Therefore, in these cases, the indication for operative treatment of so far silent aneurysms should be restricted to patients who are in good general condition with longer life expectancy as far as the vascular disease is concerned, and without major neurological deficit. Furthermore, the operative technique should be especially gentle and atraumatic.