A comparative analysis of cognitive profiles and white matter alterations using voxel-based diffusion tensor imaging between patients with Parkinson's disease dementia and dementia with Lewy bodies
- Ji Lee, E1,
- Hae-Jeong Park2,
- BoSuk Park1,
- Sook Song, K1,
- Young Sohn, H1,
- Jong Doo Lee2,
- Phil Hyu Lee1,*
- 1 Department of Neurology and Brain Research Institute, Yonsei University College of Medicine, Korea, Republic of;
- 2 Department of Diagnostic Radiology, Nuclear Medicine and Research Institute of Radiological Science, Korea, Republic of
- Correspondence to: Phil Hyu Lee, Department of Neurology, School of Medicine, Ajou University, South Korea, Department of Neurology, Ajou University, Woncheon-dong San 5, Paldal-Ku, Suwon, Kyung Ki-Do, 442-749, Korea, Republic of; phisland{at}chol.net
- Received 28 May 2009
- Accepted 24 September 2009
- Published Online First 14 October 2009
Abstract
Background: Despite clinical and neuropsychological similarities between Parkinson's disease dementia (PDD) and dementia with Lewy bodies (DLB), recent studies have demonstrated that structural and pathological changes are more severe in DLB than in PDD.
Methods: Nineteen patients with probable PDD and 18 patients with probable DLB who had similar overall severity of dementia and demographic characteristics were examined by a standardized neuropsychological test and voxel-based analysis of fractional anisotropy (FA) using diffusion tensor imaging (DTI).
Results: The patients with DLB performed significantly worse in visual recognition memory, semantic fluency, and ideomotor praxis than those with PDD (p<0.05). Compare with controls, the FA value in patients with PDD was significantly lower in bilateral frontal, left temporal, and left parietal white matters. In patients with DLB, the pattern of FA reduction was similar to that of patients with PDD, however, white matter abnormalities were more severe and extended into bilateral insular, bilateral posterior cingular, and bilateral visual association regions. In a direct comparison between PDD and DLB, the FA value in patients with DLB was significantly decreased in bilateral posterior temporal, posterior cingular, and bilateral visual association fibers extending into occipital areas.
Conclusions: Despite global similarities in cognitive performance and white matter pathology between DLB and PDD patients, those with DLB had more severely impaired frontal and temporal area-associated cognitive subsets and more severe white matter pathology in temporal and visual association fibers. Our data suggest that difference in the underlying nature of PDD and DLB may exist with global similarities in their cognitive performance and white matter pathology.
