B.J.M. van de Wetering

Quantitative study of spontaneous eye blinks and eye tics in Gilles de la Tourette's syndrome

Spontaneous eye blink rate and frequency of eye tics were studied in nine Tourette patients during periods of rest, conversation, and video watching. In comparison with controls, the Tourette patients showed a significantly higher blink rate during rest and video watching. Conversation induced a significant increase in blink rate in the control group, but not in the Tourette patients, whereas video watching significantly increased blink rate in both groups. The frequency of eye tics showed a significant decrease during conversation and increased significantly during video watching in Tourette patients. In five patients, a significant positive correlation between blink rate and eye tic frequency was found, whereas one patient showed a significant negative correlation. Our results show that, even though some of our patients were on neuroleptic treatment, blink rate was about twofold to threefold increased versus healthy controls, suggesting increased central dopaminergic activity. Furthermore, these first quantitative data illustrate task specific effects on eye tic frequency and the complexity of their relation with eye blinks.

Oculomotor control in Gilles de la Tourette syndrome.

Saccadic eye movements, fixation and smooth pursuit were studied in 28 children with Gilles de la Tourette syndrome and found to be normal. A link has been postulated between Gilles de la Tourette syndrome and other movement disorders. The results obtained in the present series do not support this hypothesis.

Contingent negative variation in adults with Gilles de la Tourette syndrome.

Three deflections or waves of the Contingent Negative Variation (CNV): the Slow Negative Wave (SNW), the Terminal CNV (TCNV) and the Post Imperative Negative Variation (PINV) were studied in 18 adults with Gilles de la Tourette syndrome and in 15 controls. The patients showed a reduced SNW, a normal TCNV and an increased PINV. Moreover, at the right parietal region the patients demonstrated a decreased SNW, TCNV and PINV. The results are discussed in relation to behavioral and neuropsychological disturbances found in Gilles de la Tourette syndrome.

Cerebellar atrophy due to chronic bromisovalum abuse demonstrated by computed tomography.

Two patients with a severe cerebellar syndrome due to chronic bromisovalum usage are described. In both patients CT scan revealed severe cerebellar atrophy. The value of computed tomography in detecting irreversible cerebellar lesions due to bromisovalum is discussed.