Basal ganglia abnormalities in tardive dyskinesia. Possible relationship with duration of neuroleptic treatment.

The purpose of the present study was to investigate CT abnormalities in tardive dyskinesia (TD) and to search for possible relationships with clinical data. A group of 30 psychotic patients (15 schizophrenic and 15 affective disorder) with TD was compared to a matched group of 30 psychiatric patients without TD and a matched group of 30 healthy controls. CT data were analyzed using two multivariate statistical methods [multidimensional scaling (MDS) and step-wise discriminant analysis]. MDS clearly separated both TD and non-TD groups from the healthy control group on the basis of CT parameters. Caudate left area reduction and left temporal sulci enlargement were the most important parameters that discriminated TD from non-TD patients. Only in TD-patients did caudate left area reduction and left temporal sulci enlargement correlate significantly with cumulative duration of psychiatric hospitalizations. The data of the present study support the findings of structural abnormalities in the caudate nucleus and in the temporal lobe of patients with TD. These abnormalities were especially marked in the left hemisphere. It is assumed that some factor related to longer psychiatric hospital treatment (e.g. neuroleptic intake) could account for these abnormalities.