Evaluation for Perfusion Areas of Bypass Flow by Intraoperative Near-infrared Indocyanine Green Videoangiography in Superficial Temporal Artery-middle Cerebral Artery Bypass Surgery

Twenty-two patients with cerebrovascular occlusive disease including 6-moyamoya disease underwent superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery between February 2007 and March 2008. In atherosclerotic cases, a single bypass between the parietal branch of STA and the posterior temporal artery was performed. In cases of moyamoya disease, a double bypass between both branches of STA and MCA (M4) on both frontal and temporal lobe with indirect bypass was performed. Perfusion areas of bypass flow from STA were evaluated by intraoperative near-infrared indocyanine green (ICG) videoangiography. This allowed unprecedented direct visualization of bypass flow in detail. In most atherosclerotic cases, perfusions of bypass flow were localized on the surface within the temporal lobe. In cases of advanced moyamoya disease, local perfusion areas only around the recipient artery were observed. This is the first report of perfusion areas of bypass flow being evaluated by intraoperative direct observation. With more cases, intraoperative ICG videoangiography may help surgeons select the recipient artery or decide if supplementary indirect bypass is necessary in moyamoya disease.