Variant Of Multiple System Atrophy Research Articles

Gray Matter Atrophy in Parkinson's Disease and the Parkinsonian Variant of Multiple System Atrophy: A Combined ROI- and Voxel-Based Morphometric Study

OBJECTIVES:Parkinson’s disease (PD) and the parkinsonian variant of multiple system atrophy (MSA-P) are distinct neurodegenerative disorders that share similar clinical features of parkinsonism. The morphological alterations of these diseases have yet to be understood. The purpose of this study was to evaluate gray matter atrophy in PD and MSA-P using regions of interest (ROI)-based measurements and voxel-based morphometry (VBM).METHODS:We studied 41 patients with PD, 20 patients with MSA-P, and 39 controls matched for age, sex, and handedness using an improved T1-weighted sequence that eased gray matter segmentation. The gray matter volumes were measured using ROI and VBM.RESULTS:ROI volumetric measurements showed significantly reduced bilateral putamen volumes in MSA-P patients compared with those in PD patients and controls (p<0.05), and the volumes of the bilateral caudate nucleus were significantly reduced in both MSA-P and PD patients compared with those in the controls (p<0.05). VBM analysis revealed multifocal cortical and subcortical atrophy in both MSA-P and PD patients, and the volumes of the cerebellum and temporal lobes were remarkably reduced in MSA-P patients compared with the volumes in PD patients (p<0.05).CONCLUSIONS:Both PD and MSA-P are associated with gray matter atrophy, which mainly involves the bilateral putamen, caudate nucleus, cerebellum, and temporal lobes. ROI and VBM can be used to identify these morphological alterations, and VBM is more sensitive and repeatable and less time-consuming, which may have potential diagnostic value.

Heightened risk of early vocal fold motion impairment onset and dysphagia in the parkinsonian variant of multiple system atrophy: a comparative study

ObjectiveWe compared differences in frequency and timing of onset of the following clinical events between the cerebellar and parkinsonian variants of multiple system atrophy (MSA-C and MSA-P, respectively): type of operation including tracheostomy and/or aspiration prevention surgery, vocal fold motion impairment (VFMI), sleep apnea (SA), introduction of mechanical ventilation (MV), and dysphagia. The risks of these events cooccurring with either MSA-C or MSA-P were compared. MethodsWe retrospectively assessed clinical outcomes only of patients with MSA who presented at the Department of Otolaryngology of the University of Tokyo Hospital between 2008 and 2018. The proportion and timing of onset events between MSA-C and MSA-P and risks of onset were compared using chi-square tests and Cox proportional hazard models adjusted for age, sex, and disease severity, respectively. ResultsWe identified 113 patients (median age: 60 years, 72 men [64%]). The frequency and timing of VFMI, SA, MV, dysphagia, and surgeries were 55 patients (49%) and 76 (95% CI 61–91) months after MSA onset, 85 (75%) and 41 (32–50), 36 (32%) and 100 (73–127), 77 (68%) and 43 (36–50), and 25 (22%) and 102 (84–120), respectively. Twenty-seven patients (24%) had MSA-P and higher risk of VFMI (p < .001), SA (p = .030), and dysphagia (p = .017) than did patients with MSA-C. ConclusionWhile MSA-P is less common, it may involve heightened risk of VFMI and dysphagia early onset. Thus, careful follow-up for VFMI, SA, and dysphagia may be needed for these patients. Criteria for Rating Diagnostic Accuracy StudiesClass II.

Diagnostic Potential of Multimodal MRI Markers in Atypical Parkinsonian Disorders.

The diagnostic potential of multimodal MRI approaches to discriminate among progressive supranuclear palsy (PSP), Parkinson variant of multiple system atrophy (MSA-P) and Parkinson's disease (PD) has not been well investigated. To identify disease-specific neurodegenerative patterns and evaluate the diagnostic accuracy of dedicated MRI, iron concentration (R2*), microstructural integrity (mean diffusivity; MD and fractional anisotropy; FA) as well as volumes were analyzed in patients with PSP, MSA-P and PD. 3T MRI of 18 PSP and 16 MSA-P patients were compared with 16 PD patients matched for age and disease duration as well as 21 healthy controls. Statistical parametric mapping (SPM) was applied to objectively identify focal MRI changes throughout the whole-brain. Following dimensionality reduction of significant and multiple comparison-corrected SPM clusters through principal component analysis (PCA), stepwise receiver-operating characteristic curve analysis (ROC) was applied to determine the diagnostic potential of multimodal MRI parameters. PCA revealed two components involving multiple regions identified from SPM analysis. The first component was primarily composed of the mean MD value of the thalamus and the mean MD and FA values of the dentatorubrothalamic tract and the corpus callosum. The second component mainly consisted of mean MD and FA values of the middle cerebellar peduncle. ROC analysis showed 92% of PSP patients were differentiated correctly from MSA-P and PD and 80% of MSA-P patients could be distinguished from PD. Multimodal MRI improved the detection of disease-specific neurodegenerative patterns in PSP and MSA-P and highlights its potential to improve the diagnostic accuracy of atypical parkinsonian disorders.

Physiotherapy improves motor function in patients with the Parkinson variant of multiple system atrophy: A prospective trial

Background and objectivesGait impairment and reduced mobility are disabling symptoms of multiple system atrophy. While physiotherapy is increasingly recognized as a valuable supplement to pharmacotherapy for patients with Parkinson's disease, data on the efficacy of physiotherapy for multiple system atrophy are lacking. This study aimed to explore the feasibility of two consecutive exercise-based interventions in patients with multiple system atrophy. Subjects and MethodsWe included 10 patients with the parkinsonian variant of multiple system atrophy and 10 patients with Parkinson's disease, matched for gender and Hoehn & Yahr stage (≤3). Interventions consisted of a five-day inpatient physiotherapy program followed by a five-week unsupervised home-based exercise program. Outcomes included instrumented gait analysis, patient questionnaires, clinical rating scales and physical tests. Patients were examined at baseline, after the first inpatient treatment and again after the home-based intervention. Additionally, a structured telephone interview was performed immediately after the second intervention period. ResultsBoth patient groups exhibited a similar improvement of gait after the interventions, as measured by instrumented gait analysis. These effects reached their maximum level after inpatient physiotherapy and remained stable following the home-based exercise program. Patient questionnaires also showed improvements after the interventions, but motor clinical rating scales did not. ConclusionOur pilot results suggest that a short-term bout of physiotherapy is feasible, safe and improves gait performance in patients with multiple system atrophy. This highlights the potential of physiotherapy for this disabling condition where pharmacotherapy typically achieves poor effects. The present findings warrant a larger controlled study.

Altered functional connectivity of dentate nucleus in parkinsonian and cerebellar variants of multiple system atrophy.

The cerebellum is known to influence cerebral cortical activity via cerebello-thalamo-cortical (CTC) circuits and thereby may be implicated in the pathophysiology of multiple system atrophy (MSA). As the aim of this study, we investigated the abnormalities of corticocerebellar functional connectivity (FC) in patients with two variants of MSA. Resting-state functional magnetic resonance imaging (rs-fMRI) studies were obtained from 55 patients with MSA, including Parkinsonian (MSAp, n = 29) and cerebellar (MSAc, n = 26) variants. We also examined a similar number of healthy controls (HC, n = 51). Seed-based connectivity analysis was performed to assess alterations in CTC circuits. Relations between FC and clinical scores were assessed as well. Compared with the HC group, diminished FC was evident from bilateral dentate nucleus (DN) to motor cortex, bilateral basal ganglia, right cerebellum, default mode network (DMN), and limbic system in patients with MSAc. Patients with MSAp (vs HC subjects) showed less FC from left DN to right putamen, DMN, and limbic systems. Reduced FC was also demonstrated from left DN to DMN in patients with MSAc (vs MSAp), as well as from right DN to right cerebellum, DMN, basal ganglia, motor cortex, and limbic systems. In addition, the extent of FC from right DN to right cerebellum negatively correlated with Unified Parkinson's Disease Rating Scale-III scores in patients with MSA, while showing a positive association with Montreal Cognitive Assessment scores. The FC of DN was similarly altered in patients with MSAc and MSAp, although right cerebellar and motor cortical changes were more widespread in the MSAc group. There may be differing mechanisms of cerebellar functional activity responsible for motor and cognitive impairment, which should be further investigated.

Differential diagnosis of multiple system atrophy with predominant parkinsonism and Parkinson's disease using neural networks

Differential diagnosis between Parkinson's disease (PD) and atypical parkinsonism, such as multiple system atrophy (MSA), can be difficult, especially in the early stages of the disease. Deep learning using neural networks (NNs) makes possible the prediction of the diagnosis using various types of biomarkers, unlike conventional linear statistics. We aimed to differentiate the Parkinson's variant of MSA (MSA-P) from PD both in the early stages by clinical utilization of NN analyses before the hot cross-bun and putaminal rim imaging features of MSA appeared. Analysis by NN involved the data of voxel-based morphometry (VBM) that indicate morphological changes and magnetic resonance spectroscopy (MRS) that indicate qualitative changes. VBM analysis showed that compared with PD patients, MSA-P patients showed atrophy in the superior cerebellar peduncle, middle cerebellar peduncle, cerebellar hemisphere, pons, midbrain, and putamen, but not in the globus pallidus. Proton MRS on the globus pallidus in the diseased hemisphere, lacking atrophy as observed with VBM, revealed decreased neurons and gliosis in both groups. Clinical differentiation of MSA-P from PD using NN analysis, involved measuring the prediction potential using the area under the receiver operator characteristic (ROC) curves (AUC). Using both VBM and MRS data, NNs contributed adequately to the clinical diagnosis.

Morphometric MRI profiles of multiple system atrophy variants and implications for differential diagnosis.

BackgroundManual width measurements of the middle cerebellar peduncle on MRI were shown to improve the accuracy of an imaging‐guided diagnosis of multiple system atrophy (MSA). Recently, automated volume segmentation algorithms were able to reliably differentiate patients with Parkinson's disease (PD) and the parkinsonian variant of MSA. The objective of the current study was to integrate probabilistic information of the middle cerebellar peduncle into an existing MRI atlas for automated subcortical segmentation and to evaluate the diagnostic properties of the novel atlas for the differential diagnosis of MSA (parkinsonian and cerebellar variant) versus PD.MethodsThree Tesla MRI scans of 48 healthy individuals were used to establish an automated whole‐brain segmentation procedure that includes the volumes of the putamen, cerebellar gray and white matter, and the middle cerebellar peduncles. Classification accuracy of segmented volumes were tested in early‐stage MSA patients (18 MSA‐parkinsonism, 13 MSA‐cerebellar) and 19 PD patients using a C4.5 classifier.ResultsPutaminal and infratentorial atrophy were present in 77.8% and 61.1% of MSA‐parkinsonian patients, respectively. Four of 18 MSA‐parkinsonian patients (22.2%) had infratentorial atrophy without evidence of putaminal atrophy. Infratentorial atrophy was present in all MSA‐cerebellar patients, with concomitant putaminal atrophy in 46.2% of these cases. The diagnostic algorithm using putaminal and infratentorial volumetric information correctly classified all PD patients and 96.8% of MSA patients.ConclusionsThe middle cerebellar peduncle was successfully integrated into a subcortical segmentation atlas, and its excellent diagnostic accuracy outperformed existing volumetric MRI processing strategies in differentiating MSA patients with variable atrophy patterns from PD patients. © 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

Distinctive speech signature in cerebellar and parkinsonian subtypes of multiple system atrophy.

Although motor speech disorders represent an early and prominent clinical feature of multiple system atrophy (MSA), the potential usefulness of speech assessment as a diagnostic tool has not yet been explored. This cross-sectional study aimed to provide a comprehensive, objective description of motor speech function in the parkinsonian (MSA-P) and cerebellar (MSA-C) variants of MSA. Speech samples were acquired from 80 participants including 18 MSA-P, 22 MSA-C, 20 Parkinson's disease (PD), and 20 healthy controls. The accurate differential diagnosis of dysarthria subtypes was based on quantitative acoustic analysis of 14 speech dimensions. A mixed type of dysarthria involving hypokinetic, ataxic and spastic components was found in the majority of MSA patients independent of phenotype. MSA-P showed significantly greater speech impairment than PD, and predominantly exhibited harsh voice, imprecise consonants, articulatory decay, monopitch, excess pitch fluctuation and pitch breaks. MSA-C was dominated by prolonged phonemes, audible inspirations and voice stoppages. Inappropriate silences, irregular motion rates and overall slowness of speech were present in both MSA phenotypes. Speech features allowed discrimination between MSA-P and PD as well as between both MSA phenotypes with an area under curve up to 0.86. Hypokinetic, ataxic and spastic dysarthria components in MSA were correlated to the clinical evaluation of rigidity, cerebellar and bulbar/pseudobulbar manifestations, respectively. Distinctive speech alterations reflect underlying pathophysiology in MSA. Objective speech assessment may provide an inexpensive and widely applicable screening instrument for differentiation of MSA and PD from controls and among subtypes of MSA.

Magnetic resonance imaging in dementia

ObjectiveTo describe and illustrate the key findings on structural magnetic resonance imaging (MRI) in the most common dementias of neurodegenerative origin: Alzheimer's disease, vascular dementia, dementia with Lewy bodies, variants of frontotemporal dementia, progressive supranuclear palsy, variants of multiple system atrophy, Parkinson dementia, and corticobasal degeneration. ConclusionToday the role of MRI is no longer limited to ruling out underlying causes of cognitive deterioration. MRI can show patterns of atrophy with a predictive value for certain dementias which, although not specific or unique to each disease, can help to confirm diagnostic suspicion or to identify certain processes. For this reason, it is important for radiologists to know the characteristic findings of the most common dementias.

Resonancia magnética en las demencias

ObjectiveTo describe and illustrate the key findings on structural magnetic resonance imaging (MRI) in the most common dementias of neurodegenerative origin: Alzheimer's disease, vascular dementia, dementia with Lewy bodies, variants of frontotemporal dementia, progressive supranuclear palsy, variants of multiple system atrophy, Parkinson dementia, and corticobasal degeneration. ConclusionToday the role of MRI is no longer limited to ruling out underlying causes of cognitive deterioration. MRI can show patterns of atrophy with a predictive value for certain dementias which, although not specific or unique to each disease, can help to confirm diagnostic suspicion or to identify certain processes. For this reason, it is important for radiologists to know the characteristic findings of the most common dementias.

123I-FP-CIT SPECT Accurately Distinguishes Parkinsonian From Cerebellar Variant of Multiple System Atrophy.

Dopamine transporter SPECT imaging is a valuable tool to estimate the integrity of presynaptic dopaminergic pathways in degenerative parkinsonisms. Evidence about SPECT differential pattern between parkinsonian and cerebellar forms of multiple system atrophy (MSA-P and MSA-C) is lacking. We aimed at assessing whether MSA-P and MSA-C variants have a distinct semiquantitative I-FP-CIT SPECT pattern. We studied a unicentric 13-year (2003-2016) retrospective cohort of subjects with possible or probable MSA and scanned with the same acquisition and reconstruction SPECT protocol. Age-dependent semiquantitative reference limits for striatal volumes of interest, asymmetry indices, and caudate/putamen ratio were previously established with a percentile approach on a cohort of subjects with nondegenerative conditions and normal visual scan. Thirty-four subjects with clinical MSA (28 MSA-P and 6 MSA-C) were identified (mean age, 68.2 ± 10.1 years; male/female ratio 1.00; disease duration, 2.5 ± 2.2 years; Movement Disorders Society Unified Parkinson's Disease Rating Scale III score, 33.8 ± 12.4). The MSA-P subjects exhibited lower uptake values for all volumes of interest, for example, striatal uptake on the more affected side (1.10 ± 0.51) compared with MSA-C (2.30 ± 0.41, P = 0.0005), as well as significantly higher asymmetry indices % (24.7 ± 24.8 vs 6.3 ± 4.5, P = 0.028) and caudate/putamen ratio (2.26 ± 1.23 vs 1.13 ± 0.17, P = 0.00148). The MSA-P and MSA-C subjects exhibited significantly distinct semiquantitative SPECT pattern with severe uptake impairment and high asymmetry for MSA-P and borderline uptake values for MSA-C. Clinical distinction of these 2 phenotypical entities is necessary in order to evaluate SPECT potential to discriminate between degenerative parkinsonisms.

Diffusion-weighted MRI distinguishes Parkinson disease from the parkinsonian variant of multiple system atrophy: A systematic review and meta-analysis.

BackgroundPutaminal diffusivity in brain magnetic resonance diffusion-weighted imaging (DWI) is increased in patients with the parkinsonian variant of multiple system atrophy (MSA-P) compared to Parkinson disease (PD) patients.PurposeWe performed a systematic review and meta-analysis to evaluate the diagnostic accuracy of DWI to distinguish MSA-P from PD.MethodsStudies on DWI were identified through a systematic PubMed and Clarivate Analytics® Web of Science® Core Collection search. Papers were selected based on stringent inclusion criteria; minimum requirement was the inclusion of MSA-P and PD patients and documented true positive, true negative, false positive and false negative rates or overall sample size and reported sensitivity and specificity. Meta-analysis was performed using the hierarchical summary receiver operating characteristics curve approach.ResultsThe database search yielded 1678 results of which 9 studies were deemed relevant. Diagnostic accuracy of putaminal diffusivity measurements were reported in all of these 9 studies, whereas results of other regions of interest were only reported irregularly. Therefore, a meta-analysis could only be performed for putaminal diffusivity measurements: 127 patients with MSA-P, 262 patients with PD and 70 healthy controls were included in the quantitative synthesis. The meta-analysis showed an overall sensitivity of 90% (95% confidence interval (CI): 76.7%-95.8%) and an overall specificity of 93% (95% CI: 80.0%-97.7%) to distinguish MSA-P from PD based on putaminal diffusivity.ConclusionPutaminal diffusivity yields high sensitivity and specificity to distinguish clinically diagnosed patients with MSA-P from PD. The confidence intervals indicate substantial variability. Further multicenter studies with harmonized protocols are warranted particularly in early disease stages when clinical diagnosis is less certain.

Simple linear brainstem MRI measurements in the differential diagnosis of progressive supranuclear palsy from the parkinsonian variant of multiple system atrophy.

Differential diagnosis of progressive supranuclear palsy (PSP) and the parkinsonian variant of multiple system atrophy (MSA-P) from Parkinson's disease (PD) can be difficult, particularly in atypical cases or early in the disease course. The Magnetic Resonance Parkinsonism Index (MRPI) utilizes linear and surface (planimetry) measurements and has been proposed as a dual MRI biomarker, with high values indicative of PSP and low values of MSA. The aim of this study was to examine the utility of simple linear MRI brainstem measurements, without the use of MRI planimetry, in the diagnosis of patients with Parkinsonism and compare them to the MRPI. A total of 51 patients (PSP: 24, MSA-P: 9, PD: 18) and 15 healthy controls were included. Simple linear MRI distances of brainstem structures were measured. These included midbrain and pons diameters as well as superior cerebellar peduncle (SCP) and middle cerebellar peduncle (MCP) widths. All relevant indices, including ratios and products, were also calculated. The SCP by midbrain product (SCP × midbrain) provided improved sensitivity (100 vs. 91%) and identical specificity (98%) for the diagnosis of PSP, compared to the MRPI. Neither the MRPI nor any of the linear measurements were able to discriminate MSA-P from PD. The SCP by midbrain product is a novel, potent MRI biomarker for PSP.

Putaminal diffusion imaging for the differential diagnosis of the parkinsonian variant of multiple system atrophy from Parkinson’s disease: Impact of segmentation accuracy

Background: It has been shown that putaminal diffusion imaging allows an early discrimination between Parkinson's disease (PD) and the parkinsonian variant of multiple system atrophy (MSA-P). Some studies were not able to confirm the role of putaminal diffusion imaging as suitable discriminator, however heterogeneity exists in the segmentation of the putamen across different studies.

Non-motor multiple system atrophy associated with sudden death: pathological observations of autonomic nuclei

Multiple system atrophy (MSA) manifests as a combination of dysautonomia and motor symptoms/signs. However, rare cases presenting with autonomic failures in absence of motor symptoms/signs until their deaths have been reported and are referred to as non-motor MSA. To clarify pathological findings underlying non-motor MSA patients, we analyzed consecutively autopsied 161 patients with MSA. In results, four patients were identified as having non-motor MSA, who showed isolated autonomic disorders throughout their lives and had minimal pathological changes in the motor systems. We also identified two patients with pathologically minimal MSA, who had minimal pathological involvement in the motor systems and presented with definite parkinsonism and dysautonomia. Survival durations of the non-motor MSA patients were much shorter (1.3-2.0years) than those of the classical MSA patients (3.0-7.0years), and the causes of death were all sudden death. The medullary serotonergic neurons were severely involved in the non-motor MSA patients in comparison with the classical MSA patients. Also, one of the pathologically minimal MSA patients had died suddenly and exhibited marked involvement of the medullary serotonergic neurons. The involvement of the medullary catecholaminergic or cholinergic neurons did not differ in severities among the groups. We conclude that non-motor MSA may be a pathological variant of MSA that preferentially involves the medullary serotonergic neurons and autonomic systems in association with poor prognosis.

Altered Functional and Causal Connectivity of Cerebello-Cortical Circuits between Multiple System Atrophy (Parkinsonian Type) and Parkinson's Disease.

Lesions of the cerebellum lead to motor and non-motor deficits by influencing cerebral cortex activity via cerebello-cortical circuits. It remains unknown whether the cerebello-cortical “disconnection” underlies motor and non-motor impairments both in the parkinsonian variant of multiple system atrophy (MSA-P) and Parkinson’s disease (PD). In this study, we investigated both the functional and effective connectivity of the cerebello-cortical circuits from resting-state functional magnetic resonance imaging (rs-fMRI) data of three groups (26 MSA-P patients, 31 PD patients, and 30 controls). Correlation analysis was performed between the causal connectivity and clinical scores. PD patients showed a weakened cerebellar dentate nucleus (DN) functional coupling in the posterior cingulate cortex (PCC) and inferior parietal lobe compared with MSA-P or controls. MSA-P patients exhibited significantly enhanced effective connectivity from the DN to PCC compared with PD patients or controls, as well as declined causal connectivity from the left precentral gyrus to right DN compared with the controls, and this value is significantly correlated with the motor symptom scores. Our findings demonstrated a crucial role for the cerebello-cortical networks in both MSA-P and PD patients in addition to striatal-thalamo-cortical (STC) networks and indicated that different patterns of cerebello-cortical loop degeneration are involved in the development of the diseases.

Deciphering the causes of sporadic late-onset cerebellar ataxias: a prospective study with implications for diagnostic work

The management of sporadic late-onset cerebellar ataxias represents a very heterogeneous group of patients and remains a challenge for neurologist in clinical practice. We aimed at describing the different causes of sporadic late-onset cerebellar ataxias that were diagnosed following standardized, exhaustive investigations and the population characteristics according to the aetiologies as well as at evaluating the relevance of these investigations. All patients consecutively referred to our centre due to sporadic, progressive cerebellar ataxia occurring after 40years of age were included in the prospective, observational study. 80 patients were included over a 2year period. A diagnosis was established for 52 patients (65%) corresponding to 18 distinct causes, the most frequent being cerebellar variant of multiple system atrophy (n=29). The second most frequent cause was inherited diseases (including spinocerebellar ataxias, late-onset Friedreich's disease, SLC20A2 mutations, FXTAS, MELAS, and other mitochondrial diseases) (n=9), followed by immune-mediated or other acquired causes. The group of patient without diagnosis showed a slower worsening of ataxia (p<0.05) than patients with multiple system atrophy. Patients with later age at onset experienced faster progression of ataxia (p=0.001) and more frequently parkinsonism (p<0.05) than patients with earlier onset. Brain MRI, DaT scan, genetic analysis and to some extent muscle biopsy, thoracic-abdominal-pelvic tomodensitometry, and cerebrospinal fluid analysis were the most relevant investigations to explore sporadic late-onset cerebellar ataxia. Sporadic late-onset cerebellar ataxias should be exhaustively investigated to identify the underlying causes that are numerous, including inherited causes, but dominated by multiple system atrophy.

Usefulness of diffusion-tensor MRI in the diagnosis of Parkinson variant of multiple system atrophy and Parkinson's disease: a valuable tool to differentiate between them?

To evaluate the differences between patients with Parkinson's disease (PD) and Parkinson variant of multiple system atrophy (MSAp) at fractional anisotropy (FA) in the white matter when using the tract-based spatial statistics (TBSS) algorithm to provide objective markers for a differential diagnosis. Diffusion-tensor imaging (DTI) data were acquired from 18 PD patients, 20 MSAp patients, and 24 healthy controls using a GE 3 T Signa HDx magnetic resonance imaging (MRI) system. The hypothesis-free whole-brain analysis (TBSS), focusing on global white matter microstructural deterioration, was adopted based on comparison among groups. Furthermore, regions of interest (ROIs) were drawn on the major fibre bundles showing abnormalities in TBSS. In the MSAp group, FA values significantly decreased in the middle cerebellar peduncle (MCP), pontine crossing tract, and corticospinal tract bilaterally. In the PD group, FA values significantly decreased in multiple supratentorial areas including the corpus callosum (CC), fornix, and left hippocampus. DTI may be an effective tool to discover pathological differences between MSAp and PD. To substantially assist the non-invasive differential diagnosis of MSAp and PD, FA measurements should not only be limited to the MCP but also the CC.

Multiple system atrophy: clinicopathological characteristics in Japanese patients.

Multiple system atrophy (MSA) is an adult-onset neurodegenerative disorder that has both clinical and pathological variants. Clinical examples include MSA with predominant cerebellar ataxia (MSA-C) and MSA with predominant parkinsonism (MSA-P), whereas olivopontocerebellar atrophy and striatonigral degeneration represent pathological variants. We performed systematic reviews of studies that addressed the relative frequencies of clinical or pathological variants of MSA in various populations to determine the clinicopathological characteristics in Japanese MSA. The results revealed that the majority of Japanese patients have MSA-C, while the majority of patients in Europe and North America have MSA-P. A comparative study of MSA pathology showed that the olivopontocerebellar-predominant pathology was more frequent in Japanese MSA than in British MSA. Demonstrated differences in pathological subtype thus appear consistent with differences in the clinical subtype of MSA demonstrated between Japan and European populations. We concluded that olivopontocerebellar-predominant pathology and MSA-C may represent clinicopathological characteristics in Japanese MSA. Factors determining predominant involvement of olivopontocerebellar regions in MSA should therefore be explored.

Causes of progressive cerebellar ataxia: prospective evaluation of 1500 patients

BackgroundCerebellar ataxias are the result of diverse disease processes that can be genetic or acquired. Establishing a diagnosis requires a methodical approach with expert clinical evaluation and investigations. We describe...