Gabapentin in the treatment of painful diabetic neuropathy: a placebo controlled, double blind, crossover trial
days with no symptomatic eVect or objective change in his AIMS score.In April 1997 ventral thalamotomy was performed on the right side in two stages under local anaesthesia.A Bennett spheroid guide had previously been inserted under general anaesthesia using CT guidance and a Leksell frame.Details of the lesions are shown in the table.The first lesion was relatively anterior and it reduced the torticollis, neck pain, hypertonia, and the dyskinesia of the contralateral limbs and allowed him to smile and laugh.One week later a second lesion was placed posteriomedial to the first.This abolished the residual "cogwheeling" of the left upper limb and improved his dexterity.There were no surgical complications.Postoperative MRI (figure) 8 months after the procedure confirms the position of the two lesions in the right thalamus.Twelve months later the patient remains well with minimal dystonic neck movements and no evidence of abnormal posturing of the left arm and oV all medication.His AIMS score is now 8/40.Although the eYcacy of thalamotomy has long been recognised in secondary dystonia 6 we are not aware of any reports of its use in drug induced dystonia.The mechanism of drug induced dystonia is not yet known and extrapolating the surgical results for treatment of dystonia of other aetiologies may not be appropriate.The reported mortality from thalamotomy ranges from 0.4% to 6%. 2 Recent experience with pallidotomy indicates an incidence of severe clinical complications of between 2%-8%. 2 Because of the proximity of the optic tract to the globus pallidus persistent visual defects are a well known risk of pallidotomy, up to 14% in one series. 3 It is too early to be certain of long term eYcacy but 12 months after operation the patient remains well and oV all medication.We conclude that thalamotomy should also be considered in patients with medically refractory drug induced tardive dystonia and dyskinesia.