[Striatonigral degeneration]

Striatonigral degeneration (SND) is sporadic, middle-aged on set degenerative disease of the nervous system which etiology is unknown. SND is considered one of multiple system atrophy (MSA). Clinically parkinsonian symptom is dominant and then it is difficult to distinguish from idiopathic Parkinson's disease (PD). Pathologically neuron cell loss and gliosis are recognized principally striatum (mainly putamen) and substantia nigra. Putaminal hypointensity and slit-hyper intensity in the outer margin of putamen are often seen on T2-weighted 1.5 Tesla MRI. PET with [18 F] fluorodeoxyglucose indicates a considerably decreased glucose utilisation in the striatum of SND, whereas glucose utilisation are normal in PD. Striatal dopamine D1, D2 receptors are reduced. Response to Levodopa is poor or absent.