Caudate atrophy in irreversible tardive dyskinesia (a pneumoencephalographic study).

Pneumoencephalography done under standard conditions on 5 patients with tardive dyskinesia and 3 matched controls revealed evidence of caudate atrophy in 3 of the dyskinetic patients. The same 3 patients proved refractory to treatment of their dyskinesia. It is concluded that tardive dyskinesia is a heterogenous entity with some patients having irreversible dyskinesia and exhibiting radiologically demonstrable damage.