A magnetic resonance imaging study of patients with Parkinson’s disease with mild cognitive impairment and dementia using voxel-based morphometry
- 1Department of Radiology, Stavanger University Hospital, Stavanger, Norway
- 2Department of Geriatric Psychiatry, Stavanger University Hospital, Stavanger, Norway
- 3Department of Neurology, Norwegian Centre for Movement Disorders, Stavanger University Hospital, Stavanger, Norway
- 4Department of Geriatric Psychiatry, Centre for Clinical Neuroscience Research, Stavanger University Hospital, Stavanger, Norway
- Correspondence to: Dr Mona K Beyer Department of Radiology, Stavanger University Hospital, PO Box 8100, N-4068 Stavanger, Norway;
- Received 21 March 2006
- Accepted 27 September 2006
- Revised 24 August 2006
- Published Online First 6 October 2006
Background: Dementia is common in Parkinson’s disease, but the underlying brain pathology is not yet fully understood.
Aim: To examine the changes in the brain of patients with Parkinson’s disease with mild cognitive impairment (MCI) and dementia, using structural magnetic resonance imaging.
Methods: Using voxel-based morphometry, the grey matter atrophy on brain images of patients with Parkinson’s disease and dementia (PDD; n = 16) and Parkinson’s disease without dementia (PDND; n = 20), and healthy elderly subjects (n = 20) was studied. In the PDND group, 12 subjects had normal cognitive status and 8 had MCI. Standardised rating scales for motor, cognitive and psychiatric symptoms were used.
Results: Widespread areas of cortical atrophy were found in patients with PDD compared with normal controls (in both temporal and frontal lobes and in the left parietal lobe). Grey matter reductions were found in frontal, parietal, limbic and temporal lobes in patients with PDD compared with those with PDND. In patients with PDND with MCI, areas of reduced grey matter in the left frontal and both temporal lobes were found.
Conclusion: These findings show that dementia in Parkinson’s disease is associated with structural neocortical changes in the brain, and that cognitive impairment in patients with PDND may be associated with structural changes in the brain. Further studies with larger groups of patients are needed to confirm these findings.
- ANCOVA, analysis of covariance
- ANOVA, analysis of variance
- FWE, family-wise error
- MCI, mild cognitive impairment
- MMSE, Mini-Mental State Examination
- MRI, magnetic resonance imaging
- PDD, Parkinson’s disease with dementia
- PDND, Parkinson’s disease without dementia
- SPM, statistical parametric mapping
- SVC, small volume correction
- VBM, voxel-based morphometry
Published Online First 6 October 2006
Funding: This work was funded by Western Norway Regional Health Authority.
Competing interests: None.