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    ABSTRACT: To investigate the diagnostic value of brain magnetic resonance image (MRI) and (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) in the differentiation of multiple system atrophy (MSA) from Parkinson's disease (PD). Thirty-five patients with MSA (23 MSA-P and 12 MSA-C) and 17 patients with PD were included in this study. Overall correct diagnosis rates between clinical and imaging diagnosis among MSA-P, MSA-C, and PD patients were 80% for visual MRI analysis, 88.5% for visual (18)F-FDG PET analysis, and 84.3% for SPM-supported analysis of (18)F-FDG PET. The sensitivity of brain MRI, and visual and SPM analysis of (18)F-FDG PET in differentiating MSA from PD was 72.7%, 90.9%, and 95.5%, respectively, the specificity was 100% for each imaging analysis, the positive predictive value was 100% for each imaging analysis, and the negative predictive value was 60%, 81.8%, and 90%, respectively. Our results suggest that brain MRI and (18)F-FDG PET are diagnostically useful in differentiating MSA (MSA-P and MSA-C) from PD, and indicate that (18)F-FDG PET has a tendency toward higher sensitivity compared to brain MRI, but a larger longitudinal study including pathological data will be required to confirm our findings.
    Movement Disorders 01/2008; 22(16):2352-8. · 4.56 Impact Factor
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    ABSTRACT: The rate of brain atrophy and its relationship to clinical disease progression in progressive supranuclear palsy (PSP) and multiple system atrophy (MSA) is not clear. Twenty-four patients with PSP, 11 with MSA-P (Parkinsonian variant), 12 with Parkinson's disease, and 18 healthy control subjects were recruited for serial MRI scans, clinical assessments and formal neuropsychological evaluations in order to measure brain atrophy during life and its association with disease progression in PSP and MSA-P. Serial scans were registered and rates of whole brain atrophy calculated from the brain-boundary shift integral. Regional rates of atrophy were calculated in the brainstem (midbrain and pons), the cerebellum, the lateral and third ventricles as well as frontal and posterior inferior brain regions, by locally registering to a region of interest in order to derive a local boundary shift integral (BSI). 82% of recruited subjects completed serial MRI scans (17 PSP, 9 MSA-P, 9 Parkinson's disease patients and 18 healthy controls). Mean (SD) annualized rates of whole-brain atrophy were greatest in PSP: 1.2% (1.0%), three times that in controls. Mean (SD) midbrain atrophy rates in PSP, 2.2% (1.5%), were seven times greater than in healthy controls. In MSA-P, atrophy rates were greatest in the pons: 4.5% (3.2%), over 20 times that in controls and three times the rate of pontine atrophy in PSP. Atrophy rates in Parkinson's disease were not significantly different from control rates of atrophy. Variability in the atrophy rates was lower when calculated using the BSI rather than manual measurements. Worsening motor deficit was associated with midbrain atrophy in PSP, and ponto-cerebellar atrophy in MSA-P. Worsening executive dysfunction was associated with increased rates of frontal atrophy in PSP. Cerebellar atrophy rates were better discriminators of MSA-P than cross-sectional volumes. We confirm that serial MRI can be applied to measure whole brain and regional atrophy rates in PSP and MSA-P. Regional rather than whole-brain atrophy rates better discriminate PSP and MSA-P from healthy controls. Clinico-radiological associations suggest these regional atrophy rates have potential as markers of disease progression in trials of novel therapies.
    Brain 05/2006; 129(Pt 4):1040-9. · 9.92 Impact Factor
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    ABSTRACT: Our study aimed to describe the clinical features of multiple system atrophy (MSA) in Singapore and verify its diagnosis using the consensus statement in the diagnosis of MSA. All patients suspected to have MSA between 1995 and March 2005 were identified from the Movement Disorders database and the autonomic function testing results. The medical records were reviewed using a standardised data collection form. The diagnosis of MSA was verified using the consensus statement. Disease progression was evaluated using 2 pre-determined events: aid-requiring walking and wheelchair use. Seventy-two per cent (33/46) fulfilled the consensus statement. There were 85% Chinese, 9% Malays, and 6% Indians. The mean age at onset of the disease was 60 +/- 10 years. We found a predominance of males (M:F = 1.5:1) as well as MSA-C cases (67%). The most common initial presenting features were parkinsonism and cerebellar signs (27% each). Abnormal neuroimaging was seen in 29 patients (91%). Autonomic function testing was abnormal in 58% (7/12). The risk for aid-requiring walking and wheelchair use at 3 years from onset of the disease was 31% and 17%, respectively. By 5 years, this had increased to 45% and 30%, respectively. There was no difference in the events rate between MSA subtypes. The clinical characteristics of MSA in Singapore are presented. Our study revealed a predominance of MSA-C patients as well as a later age at onset of disease and longer median time to aid-requiring walking and wheelchair use compared to Japanese patients.
    Annals of the Academy of Medicine, Singapore 11/2005; 34(9):553-7. · 1.36 Impact Factor