Reduction of the substantia nigra width and motor decline in aging and Parkinson's disease
J. Pujol, C. Junque, P. Vendrell, J. M. Grau and A. Capdevila
Department of Neurology, Sta Creu i St Pau Hospital, Autonomous University of Barcelona, Spain.
We studied the functional significance of the involutional and degenerative
changes in the substantia nigra as seen on magnetic resonance imaging. The
width of the pars compacta correlated with motor performance in both
healthy elderly subjects and idiopathic Parkinson's disease groups.
Patients exhibited significant reduction of the width of the pars compacta
and the level of this reduction correlated strongly with the clinical
status evaluated by the Unified Parkinson's Disease Rating Scale. These
results suggest that pars compacta shrinkage may account for a substantial
part of the structural substratum of motor decline in the elderly.
Moreover, an analysis of the relationship of the midbrain damage with
specific symptoms in Parkinson's disease could contribute to a better
understanding of the pathogenesis of this degenerative process.