gms | German Medical Science

Recently, intraoperative fluorescence angiography by indocyanine green (ICG) has been introduced as a novel technique to confirm successful aneurysm clipping. The aim of the present study was to assess whether ICG video angiography is also suited to intraoperatively confirm EC-IC bypass patency.

Twenty-one patients undergoing cerebral revascularization for hemodynamic cerebral ischemia (n=6), moya-moya disease (n=10), giant aneurysms (n=4) and a large skull base meningeoma (n=1) were included. STA-MCA (superficial temporal artery-middle cerebral artery) bypass surgery was performed in 17 patients and saphenous vein high-flow bypass surgery in 4 patients. ICG was given systemically by intravenous bolus injection (25 mg; n=25) and/or selectively by injection via a small branching vessel of the superficial temporal artery (0.5 mg; n=9). A near-infrared light emitted by laser diodes was used to illuminate the operating field and the intravascular fluorescence was recorded by a optical filter equipped video camera. ICG video angiography findings were compared with postoperative digital subtraction angiography or computed tomography angiography. In selected patients (n=6) perfusion changes before and after bypass surgery have been analyzed.

In all cases excellent visualization of cerebral arteries, the bypass graft and brain perfusion could be realized. In three patients lack of adequate bypass patency was reliably identified leading to successful revision of the bypass anastomosis. In 21 of 22 cases postoperative findings correlated with ICG video angiography.

ICG video angiography allows to reliably visualize intraoperative bypass patency and brain perfusion. Thus, ICG video angiography may help to reduce the incidence of early bypass graft failure.