Occipital-posterior cerebral artery bypass via the occipital interhemispheric approach
A 65-year-old male was admitted to our hospital due to a decreased level of consciousness, nausea, and cerebellar ataxia. Symptoms progressed along with an increase in the size of ischemic lesions in the pons, cerebellum, thalamus, and occipital lobe on DWI, despite intensive medical treatment. Angiography revealed severe stenosis of the left VA, occlusion of the mid-basilar artery, and leptomeningeal anastomosis from the MCA to the PCA []. IMP and SPECT revealed reduced rCBF in the bilateral cerebellar hemispheres and bilateral PCA territory. The patient underwent successful left OA-PICA bypass and right OA-SVG-PCA bypass []. Postoperative angiography revealed opacification of the left distal VA through the OA-PICA bypass and opacification of the upper basilar artery via the OA-PCA bypass []. No neurological deterioration was observed postoperatively. Angiography obtained 1 month postoperatively and MRA obtained 2 months postoperatively both revealed bypass patency.