Changes in superficial temporal artery blood flow and cerebral hemodynamics after extracranial-intracranial bypass surgery in moyamoya disease and atherothrombotic carotid occlusion

This study included 40 consecutive patients with athrothrombotic carotid occlusive disease (A-group) and 13 consecutive patients with moyamoya disease (M-group) who had an internal carotid artery occlusion and underwent EC-IC bypass. Flow velocity and diameter of the operated STA on duplex ultrasonography (STDU), as well as regional cerebral blood flow (rCBF) on single photon emission computed tomography (SPECT) were measured before, 14 days after, and 3 months after EC-IC bypass. The postsurgical changes in the ipsilateral STA mean flow velocity (MFV) were significantly higher (p = 0.0030) and those in the rCBF in the MCA territory were relatively higher (p = 0.0936) in the M-group than the A-group patients. On 14 days after EC-IC bypass, the STA MFV (76.0 ± 22.5 vs 55.2 ± 16.5 cm/s, p = 0.0006) and the rCBF (40.0 ± 8.0 vs 34.2 ± 5.9 ml/100 g/min, p = 0.0065) were significantly higher in the M-group than in the A-group. On 3 months after EC-IC bypass, these differences in the STA MFV or the rCBF disappeared. There were no significant differences in the postsurgical STA diameter and the ACZ reactivity between both groups. Changes in the STA MFV as well as the rCBF were higher in moyamoya disease than atherothrombotic carotid occlusive disease in the early phase after EC-IC bypass. The STA MFV is highly correlated with the rCBF after EC-IC bypass.