Transcranial Doppler ultrasonography in patients with moyamoya disease.

This study included 17 patients (five men and 12 women) with clinical diagnosis of Moyamoya disease from conventional angiograms. Bilateral basal arteries were measured by the transtemporal approach with a 2 MHz pulsed Doppler instrument (TC-2 64B EME). In 28 out of the 34 basal arteries (82.4%), reliable recordings were obtained. These transcranial Doppler ultrasonography (TCD) findings were classified into three patterns: (1) High-high pattern; the mean cerebral blood flow velocity (CBFV) was increased throughout the basal arteries by over 70 cm/s (seven arteries, 25.0%); (2) high-low pattern; the mean CBFV was fastest (over 70 cm/s) at the ICA or proximal MCA and the mean CBFV decreased remarkably distally (15 arteries, 53.6%); and (3) low-low pattern; the mean CBFV was less than 40 cm/s throughout the basal arteries (arteries, 15.4%). These CBFV patterns as assessed by TCD are compared with the patients age, clinical symptoms and angiographical stagings (Suzuki's criteria). The high-high pattern on TCD was predominantly seen in the younger patients and in the earlier stages of the disease. The high-low pattern was the most common pattern of CBFV as assessed by TCD in Moyamoya patients. The low-low pattern on TCD was more common in the later stages following angiographic evaluation by Suzuki's criteria. The above patterns based on TCD findings show a good correlation with the age of the patient and the clinical diagnosis at the onset. TCD appears to be very useful in the evaluation of patients with Moyamoya disease.