Abstract
The skin blood flow (periflux blood flow: PBF) in the finger tip was measured with a periflux laser doppler flowmeter (PLDF). PLDF is a new instrument for the direct, continuous and noninvasive measurement of blood flow in skin capillaries. A 2 mW He-Ne laser was used as the light source.
In the present study, the pattern of PBF was evaluated as a measure of diabetic auto nomic neuropathy.
The response upon standing was studied in 78 normal subjects and 52 diabetic patients and its pattern was classified into four types. The response time (RT) and orthostatic dysreaction ratio (ODR) were chosen as indices of the PBF response.
The results obtained were as follows.
1) Ninety-five percent of normal subjects showed a normal response pattern. On the other hand, about half of the diabetic patients showed abnormal response patterns. That is, 27%, 23% and 6 % of the diabetic patients were of the “delayed recovery type”, “incomplete recovery type”, and “other type”, respectively.
2) The RT in normal subjects was 15.3±5.7 sec (mean±S.D.). The correlation coefficient between RT and the motor conduction velocity was-0.504 (p<0.025) and that between RT and the sensory conduction velocity was-0.444 (p<0.05).
3) Significant negative correlations were found between ODR and ΔP (blood pressure fall)(r=-0.817, 0.817, p<0.001) and ΔP (change in pulse rate) on standing (r=-0.802, p<0.005).
4) The diabetic patients were divided into two groups according to the presence or absence of diabetic autonomic neuropathy, i.e. “Symptomatic” and “asymptomatic” groups. There were significant differences in RT and ODR values between the two groups (RT: p<0.005, ODR: p<0.05).
These results suggest that measurement of PBF is clinically useful for evaluating diabetic complications.
