Open AccessComprehensive morphometry of subcortical grey matter structures in early‐stage Parkinson's disease
Author(s) -
Menke Ricarda A.L.,
SzewczykKrolikowski Konrad,
Jbabdi Saad,
Jenkinson Mark,
Talbot Kevin,
Mackay Clare E.,
Hu Michele
Publication year - 2014
Publication title -
human brain mapping
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.005
H-Index - 191
eISSN - 1097-0193
pISSN - 1065-9471
DOI - 10.1002/hbm.22282
Subject(s) - grey matter , subthalamic nucleus , thalamus , voxel based morphometry , globus pallidus , psychology , neuroscience , voxel , tractography , basal ganglia , diffusion mri , pedunculopontine nucleus , putamen , frontal lobe , midbrain , white matter , brain morphometry , parkinson's disease , pathology , magnetic resonance imaging , medicine , central nervous system , disease , radiology , deep brain stimulation
Previous imaging studies that investigated morphometric group differences of subcortical regions outside the substantia nigra between non‐demented Parkinson's patients and controls either did not find any significant differences, or reported contradictory results. Here, we performed a comprehensive morphometric analysis of 20 cognitively normal, early‐stage PD patients and 19 matched control subjects. In addition to relatively standard analyses of whole‐brain grey matter volume and overall regional volumes, we examined subtle localized surface shape differences in striatal and limbic grey matter structures and tested their utility as a diagnostic marker. Voxel‐based morphometry and volumetric comparisons did not reveal significant group differences. Shape analysis, on the other hand, demonstrated significant between‐group shape differences for the right pallidum. Careful diffusion tractography analysis showed that the affected parts of the pallidum are connected subcortically with the subthalamic nucleus, the pedunculopontine nucleus, and the thalamus and cortically with the frontal lobe. Additionally, microstructural measurements along these pathways, but not along other pallidal connections, were significantly different between the two groups. Vertex‐wise linear discriminant analysis, however, revealed limited accuracy of pallidal shape for the discrimination between patients and controls. We conclude that localized disease‐related changes in the right pallidum in early Parkinson's disease, undetectable using standard voxel‐based morphometry or volumetry, are evident using sensitive shape analysis. However, the subtle nature of these changes makes it unlikely that shape analysis alone will be useful for early diagnosis. Hum Brain Mapp 35:1681–1690, 2014 . © 2013 Wiley Periodicals, Inc.