Impaired vibratory perception as a criterion of diabetic neuropathies

Among neurological findings in diabetics, increased vibratory perception threshold (VTP) and abnormal ankle jerks are thought to be two of the most common. This study aims to determine the diagnostic value of VPT by C128-vibrometer. Mean VPT in a reference group composed of 278 non-diabetics showed regression with age, so the normal range was determined as lying below M + 2SD for each 10 year age range in the reference group. The mean VPT in each age group of 667 diabetic subjects was found to be approximately equal to M + 1SD of the values for the non-diabetics. After 10 days on a proper diet in the hospital, VPT showed a marked improvement in well controlled cases. In a 3 year follow up study, it was found that constant impairment of vibratory perception was common in the group with a high prevalence of microangiopathies. Though impaired VPT is reversible, it is useful as a diagnostic aid for diabetes.