Many useful diagnostic methods such as needle EMG, motor and sensory nerve conduction velocity, F-wave, H-reflex, somatosensory evoked potential and blink reflex were used in diabetic neuropathy.

The purpose of this study was to observe the cranial nerve involvement in diabetes mellitus by using blink reflex and facial nerve conduction time. The subject was composed of 41 diabetic patients who had been admitted to Seoul National University Hospital and diagnosed to have diabetic neuropathy.

The result were as follows:

1) Total 41 cases were composed of 23 males (56%) and 18 females (44%) with mean age of 56.6 years. The mean duration of the diabetes mellitus was 11.22 years and the mean fasting blood sugar level was 186 mg/100 ml.

2) The mean latency of the blink reflex was delayed in diabetic neuropathy with statistical significance and there was cranial nerve involvement in 22 cases (54%) of total 41 diabetic neuropathies.

3) The R/D ratio in diabetic neuropathy was decreased with statistical significance, which means that the distal involvement was more severe in diabetic neuropathy.

4) There was no correlation between the blink reflex latency and the fasting blood sugar or the duration of the diabetes mellitus.

5) The abnormality of the blink reflex was correlated mostly with the abnormal motor nerve conduction velocity, followed by sensory nerve conduction velocity and somatosensory evoked potential with statistical significance.

6) The most sensitive test to diagnose the diabetic neuropathy was sensory nerve conduction velocity, follwed by motor nerve conduction velocity, somatosensory evoked potential and blink reflex.