経頭蓋超音波法によるモヤモヤ病診断のクライテリア

抄録

Intra- and extra cranial hemodynamics and vascular reactivity were studied with transcranial Doppler ultrasound (TC2-64B) in patients with Moyamoya disease and the criteria for diagnosis were proposed. Studies were conducted in 15 normal subjects and 15 patients with angiographically proven Moyamoya disease. In 11 patients who received vascular reconstruction operations, such as STA-MCA anastomosis, EDAS, RDP (reversed durapexia) and EMS, studies were performed before and after the operation. We cited the following findings as criteria for diagnosis: 1) A significant decrease in flow velocity of the cerebral arteries (MCA, ACA), although coexistence of decreased and increased velocities side by side were also noticed. 2) Decrease or absence of vascular reactivity to hypocapnia. 3) Transformation of the STA flow velocity wave form from an external carotid artery pattern to internal carotid pattern. 4) A significant increase in the flow velocity of the ophthalmic artery and transformation of the wave form. These changes were seen more remarkably in cases with abundant transdural anastomosis. If we obtained findings 1) and 2), Moyamoya disease was suspected. When additional findings 3) and/or 4) were obtained, the possibility of the disease was very high. The findings of TCD post-operatively, were also useful. If the STA was patent and functioning well, the flow velocity of STA increased dramatically and the flow pattern became similar to the internal carotid pattern.
Observations of these pre- and postoperative characteristic changes in flow velocity and vascular reactivity in patients with Moyamoya disease see to be quite useful for the evaluation of the hemodynamics and should provide information for a follow-up study.