Parent artery occlusion with bypass surgery for the treatment of internal carotid artery aneurysms: Clinical and hemodynamic results

Objective: Parent artery occlusion with/without bypass surgery is one of the treatment choices for the internal carotid artery (ICA) aneurysm difficult to treat by clipping or coiling. There have been few reports regarding postoperative cerebral blood flow (CBF) changes after surgery. This study evaluated the present bypass selection strategy based on balloon test occlusion (BTO) in terms of clinical and hemodynamic outcomes. Methods: Twenty-one consecutive patients with ICA aneurysms underwent parent artery occlusion. High flow bypass (n = 9), superficial temporal artery-middle cerebral artery bypass (n = 10), or no bypass (n = 2) was performed depending on the changes in clinical symptoms and CBF during BTO. Quantitative CBF measurement with acetazolamide challenge was performed in the chronic stage. Results: Overall outcome at discharge was good recovery 18, moderate disability 2, and severe disability 1. Two patients suffered symptomatic embolic or perforator infarction associated with the surgical manipulations. Preoperative cranial nerve pareses improved completely or partially in all patients except one. CBF in the chronic stage (n = 18) demonstrated no significant difference between the surgical and non-surgical cerebral hemispheres. No cerebral ischemic event was observed during the follow-up period (mean 2.9 years). Conclusion: The present surgical strategy based on preoperative BTO provides a reliable tool to achieve acceptable clinical and hemodynamic outcomes in patients with complex ICA aneurysms to be treated by parent artery occlusion.