Long-term abolition of Parkinsonian tremor following attempted ventriculography

Three patients are described who were selected for stereotactic thalamotomy to alleviate the tremor and rigidity of Parkinson's disease but in whom these symptoms were abolished whilst attempting ventriculography. Discrete deep brain lesions were seen on post-operative CT scan and the basis for their relieving the patients' symptoms is discussed. Although the tremor and rigidity was abolished in these cases and a favourable result ensued, ventriculography is an invasive and potentially dangerous procedure and it is therefore recommended that CT-derived thalamic targets should be employed for functional stereotaxy.