Objective
The purpose of this study was to evaluate hemodynamics for diabetes mellitus (DM) by transcranial Doppler sonography (TCD) and to evaluate the influences of risk factors to cerebral hemodynamics in DM.

Method
We examined 54 normal persons, 17 patients with DM without risk factors, and 15 patients with DM and risk factors. The risk factors were hypertension, smoking, and hyper lipidemia (total cholesterol ＞240 mg/dl, low density lipoprotein ＞160 mg/dl). Mean blood flow velocity (MBFV) was also analyzed by Angiodine 2 Doppler system operating at 2 MHz frequency from each subjects.

Results
There was a significant decrease of MBFV in the diabetes in comparison to control groups (p＜0.05). There was a significant decrease of MBFV in the diabetic risk group as compared to diabetic non-risk group (p＜0.05). There was significantly increased total cholesterol, low density lipoprotein, low density lipoprotein/high density lipoprotein ratio in the diabetic risk group as compared to diabetic non-risk group (p＜0.05). MBFV significantly decreased with increasing concentration of HbA1C and duration of DM (p＜0.05).

Conclusion
We suggest that transcranial Doppler sonography can be used as one of the useful screening tests for early detection of cerebrovascular diseases in DM.