Abstract
Background: Extracranial-intracranial (EC-IC) bypass is a powerful tool for treating complex cerebral aneurysm. Ruptured aneurysms at the non-branching site of the internal carotid artery (ICA), the so-called blister-like aneurysm, have been treated with high flow EC-IC bypass and aneurysmal trapping, but postoperative cerebral hemodynamics following flow conversion have remained unclear.
Methods: The present study investigated six cases with ruptured blister-like ICA aneurysm, who were managed by high flow EC-IC (ECA-M2 or CCA-M2) bypass using interposed saphenous vein graft followed by microsurgical aneurysmal trapping. Postoperative cerebral blood flow (CBF) was evaluated by N-isopropyl-p-[123I]iodoamphetamine single-photon emission computed tomography (SPECT) in the acute stage. Routine magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) were also performed in the acute stage.
Results: No patient suffered from intra-operative aneurysmal rupture, and no patient manifested procedure-related ischemic complications. Postoperative SPECT in the acute stage (1‐3 days after surgery) demonstrated a mild decrease in CBF in the operated hemisphere. Postoperative MRA demonstrated apparently patent EC-IC bypass in all cases. One patient manifested a delayed vasospasm and required a diagnostic angiogram and an intra-arterial infusion of fasudil hydrochloride. The clinical outcome was as follows: GR (good recovery) in four patients, and MD (moderately disabled) in two patients.
Conclusion: High flow EC-IC bypass followed by aneurysmal trapping (ICA trapping) was found to be a safe and effective treatment for ruptured blister-like ICA aneurysm. We recommend postoperative SPECT and MRI/MRA in the acute stage to monitor cerebral hemodynamics after flow conversion.
