MAGNETIC-RESONANCE-IMAGING IN EXTRAPYRAMI DAL DISORDERS - PARKINSONS-DISEASE, PROGRESSIVE SUPRANUCLEAR PALSY, MULTIPLE SYSTEM ATROPHY

MR imaging of the brain, particularly with high field MR imagers, may demonstrate signal abnormalities consistent with deposits of iron or o ther paramagnetic substances in extrapyramidal disorders. The diagnosi s of Parkinson's disease and progressive supranuclear palsy can be mad e on clinical grounds in most of the cases and MR signs are of little help in the diagnosis of these diseases. In patients with parkinsonian disorders poorly responding to therapy, MR imaging may be useful in d emonstrating signal abnormalities in the putamen that may help to esta blish the diagnosis of striatonigral degeneration (component of multip le system atrophy) with a poorer prognosis than Parkinson's disease. F inally, MR imaging may be useful in the exclusion of other disease pro cesses.