[Parameters of arterial occlusion during intracranial aneurysm surgery]

To evaluate parameters, owing to temporary and/or permanent intraoperative arterial occlusion, could be related to the postoperative development of ischemic injury.

During 3-year period between October 1994 and March 1997, 27 patients with intracranial aneurysm were operated on with the aid of temporary and/or permanent arterial occlusion. Continuous intraoperative monitoring lCBF of the territories undergoing occlusion was carried out using LDF. Univariate analysis was used to study the relationship between the study variable and cerebral infarction. These variables included patient age, sexuality, aneurysm size, preoperative Hunt and Hess grades, LDF baseline value, LDF value following arterial occlusion and release of occlusion, the duration of arterial occlusion, the numbers of occlusive episodes, and the degree of arterial occlusion. Student's t-test was used for comparison of continuous variable such as age, and chi-square analysis was used to test the association of categorical variables.

The LDF value following arterial occlusion or residual lCBF, the duration of arterial occlusion, the numbers of occlusive episodes, and the occlusive degree were found to be significantly related to the postoperative development of ischemic injury.

The residual lCBF and collateral circulation following arterial occlusion can be evaluated using LDF monitoring. When residual lCBF is more than 50 per cent of the baseline and the duration of arterial occlusion less than 20 minutes, temporary arterial occlusion is safe and does not develop postoperative ischemic injury.