Improvement of hypertonus after treatment for sleep disturbances in three patients with severe brain damage.

Treatment for sleep disturbance was given to three patients with severe brain damage (a 14-year-old boy, an 8-year-old girl and a 9-year-old boy), and changes in their muscle tone were estimated using F-wave analysis. In all patients, F-wave analysis was performed in the ulnar nerve before and 2 weeks after treatment with flunitrazepam or melatonin. From 16 recordings of F-waves, the mean amplitude and latency, the ratio of F-wave amplitude to M-wave amplitude (F/M ratio), the mean F-wave conduction velocity and the F-wave occurrence were evaluated. All patients showed at least one significant decrement of mean F-wave amplitude, the F-wave occurrence and mean F/M ratio, which suggests a reduction in muscle tone after treatment for sleep disturbance. It is concluded that treatment for sleep disturbance occurring in brain damage is important in view of the improvement of increased muscle tone.