Heroin myelopathy.

Abstract

CT scan evidence of a mid-brain lesion.The relationship between this patient's lesion in the white matter, below the sen- sory motor cortex, and close to the roof of the lateral ventricle, and a "penduncular" tremor is difficult to explain.Cortical lesions may produce a tremor as seen in three personally studied cases where a tre- mor was associated with a small frontal tumour on or near the surface of the brain.In such cases however the tremor is Parkin- sonian in type and there is often associated rigidity.It is of course well recognised that tre- mor may respond dramatically to stereotaxic thalamotomy whether it is due to Parkinsonism, essential tremor, or the mid-brain lesion of multiple sclerosis or head injury.It is of interest that this patient's tremor associated with a deep hemisphere white matter lesion was equally responsive to thalamotomy.We are grateful to Dr EJ Thompson for CSF electrophoresis, and Dr Linda Luxon for the neuro-otological studies and to