title: Susceptibility-weighted MRI of extrapyramidal brain structures in Parkinsonian disorders.
abstract: Susceptibility-weighted MRI (SWI) is sensitive to T2 effects and mineralization.We investigated differences in the extrapyramidal brain structures on SWI between Parkinson disease (PD) and postural instability gait disorder (PIGD) patients and correlated the SWI values with the degree of gait dysfunction.Forty patients diagnosed with PD and PIGD underwent 3 Tesla magnetic resonance imaging (MRI) brain study. An SWI sequence (TE/TR/FA 20/33/15) was used. Ten regions of interest were placed in the midbrain and basal ganglia by 2 independent raters blinded to subject data and quantitatively evaluated.The inter-rater reliability between the raters was excellent (interclass correlation coefficient >0.8). The SWI intensity values in all regions were on average lower in PIGD than in PD patients, with the lowest results found in globus pallidus.Multivariate analysis showed a lower SWI hypointensity in the putamen and globus pallidus in PIGD compared with PD patients, with a similar trend for the other basal ganglia nuclei. Pearson correlation analysis showed a statistically significant positive correlation between SWI putaminal hypointensity and the Tinetti total score (r = 0.39, P = 0.01) in both PD and PIGD.SWI putaminal hypointensity may be a useful imaging marker in prospective evaluation for clinical progression for Parkinsonian disorders.
authors.affiliation: aDepartments of Diagnostic Radiology bClinical Research, Singapore General Hospital cDepartment of Neurology, National Neuroscience Institute dDuke-NUS Medical School, Singapore.
authors.forename: Eva
authors.initials: E
authors.lastname: Schneider
authors.forename: Kia-Min
authors.initials: KM
authors.lastname: Ng
authors.forename: Chooi-Sum
authors.initials: CS
authors.lastname: Yeoh
authors.forename: Helmut
authors.initials: H
authors.lastname: Rumpel
authors.forename: Stephanie
authors.initials: S
authors.lastname: Fook-Chong
authors.forename: Hui-Hua
authors.initials: HH
authors.lastname: Li
authors.forename: Eng-King
authors.initials: EK
authors.lastname: Tan
authors.forename: Ling-Ling
authors.initials: LL
authors.lastname: Chan
mesh_terms: D000368:Aged; D001921:Brain / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D020734:Parkinsonian Disorders / Q000000981:diagnostic imaging*