title: Symptomatic characteristics of parkinsonism and the width of substantia nigra pars compacta on MRI according to ischemic changes in the putamen and cerebral white matter: implications for the diagnosis of vascular parkinsonism.
abstract: To investigate the significance of vascular lesions as a cause of secondary parkinsonism, we analyzed the symptomatic characteristics, the width of the substantia nigra pars compacta (SNpc) on MRI and the responsiveness to L-dopa in 227 parkinsonian cases, excluding those with drug-induced parkinsonism and neurodegenerative diseases other than idiopathic Parkinson's disease (IPD). They were classified into those without a significant infarct in the basal ganglia (n = 144), those with status lacunaris in the putamen (SLP; n = 66) and those with confluent white matter hyperintensity signals (CWMH; n = 17). The 4- to 6-Hz tremor and cogwheel rigidity were significantly more frequent in cases without significant infarct (69%) than those with SLP (50%) and those with CWMH (12%; p < 0.05). Among cases with 4- to 6-Hz tremor and cogwheel rigidity, the frequency of patients with a reduced SNpc width and L-dopa responders did not significantly differ between those with SLP (73 and 83%, respectively) and those without significant infarct (83 and 86%, respectively), suggesting that the diagnosis for most of these cases would be probable IPD. In contrast, among cases without 4- to 6-Hz tremor and cogwheel rigidity, those with a reduced SNpc width or L-dopa responders were significantly less frequent among cases with SLP (25 and 38%, respectively) than among those without significant infarct (75 and 71%, respectively; p < 0.05). Patients with neither 4- to 6-Hz tremor and cogwheel rigidity nor reduction in the SNpc width, for whom the probable diagnosis was vascular parkinsonism (VP), were significantly more frequent in cases with SLP (26%) and with CWMH (40%) than those without significant infarct (8%), accounting for 10.6% of the total parkinsonian cases. These findings suggest that parkinsonian cases with SLP or CWMH consist of not only cases with vascular-lesion-related VP but also IPD in which vascular lesions are not directly related to parkinsonism. Absence of 4- to 6-Hz tremor, cogwheel rigidity and the reduction in the SNpc width could be indicators for differentiating VP from IPD.
authors.affiliation: Department of Neurology, Iwate Medical University, 19-1 Uchimaru Morioka, Iwate 020, Japan. htohgi@iwate-med.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Tohgi
authors.forename: S
authors.initials: S
authors.lastname: Takahashi
authors.forename: T
authors.initials: T
authors.lastname: Abe
authors.forename: K
authors.initials: K
authors.lastname: Utsugisawa
mesh_terms: D000368:Aged; D000978:Antiparkinson Agents / Q000627:therapeutic use; D020520:Brain Infarction / Q000473:pathology / Q000503:physiopathology; D002545:Brain Ischemia / Q000473:pathology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007980:Levodopa / Q000627:therapeutic use; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology; D009127:Muscle Rigidity / Q000503:physiopathology; D010300:Parkinson Disease / Q000188:drug therapy / Q000473:pathology* / Q000503:physiopathology*; D010302:Parkinson Disease, Secondary / Q000175:diagnosis* / Q000503:physiopathology*; D011699:Putamen / Q000098:blood supply* / Q000473:pathology* / Q000503:physiopathology; D013378:Substantia Nigra / Q000473:pathology* / Q000503:physiopathology
chemical_list: D000978:Antiparkinson Agents; D007980:Levodopa