A study of acupuncture in Asian patients: clinical aspects and effects on cortical excitability.

OBJECTIVE

To determine the effect of acupuncture on the phosphene threshold, by transcranial magnetic stimulation (TMS), and the clinical effect of acupuncture on headache frequency, duration and severity.

METHODS

Twenty-one patients (16 women; mean age 46 years; range 23-61 years, 17 Chinese, 2 Malays, 2 Indians) underwent 10 acupuncture sessions scheduled twice a week for 5 weeks. The lowest TMS intensity to elicit phosphene perception is defined as the phosphene threshold. TMS was performed before the first and last sessions, and at 2 months' follow-up.

RESULTS

Acupuncture resulted in reduction of headache frequency, duration and severity over the course of treatment. However, this was not accompanied by a corresponding increase in the phosphene threshold over a similar time course. The baseline threshold before acupuncture treatment had no predictive value for outcome of treatment.

CONCLUSIONS

Although acupuncture was effective in treating migraine, the use of occipital cortex excitability as an adjunctive parameter to evaluate treatment response was not suitable. The relief of migraine with acupuncture may be related to separate neural pathways independent of occipital or visual processes in the human brain.