Patterns of gray matter atrophy in atypical parkinsonism syndromes: a VBM meta‐analysis

Abstract

Background and PurposeAccurate diagnosis of Atypical Parkinsonian Syndromes (APS) is important due to differences in prognosis and management, but remains a challenge in the clinical setting. The purpose of our meta-analysis was to identify characteristic patterns of gray matter atrophy in Corticobasal Degeneration (CBD), Progressive Supranuclear Palsy (PSP), Multisystem-Atrophy Parkinsonian type (MSA-P), and Idiopathic Parkinson's Disease (IPD).Materials and MethodsWhole-brain meta-analysis was performed on 39 published voxel-based morphometry (VBM) articles (consisting of 404 IPD, 87 MSA-P, 165 CBD, and 176 PSP subjects) using the modified Anatomic Likelihood Estimation method. Based on these results, contrast analyses were then utilized to determine areas of atrophy shared by as well as unique to each disorder.ResultsCBD was characterized by asymmetric gray matter atrophy in multiple cortical regions, while the thalamus-midbrain and insula were predominantly involved in PSP. The striatum and superior cerebellum were affected in MSA-P, while IPD demonstrated an anterior cerebral pattern. Although there was a mild overlap among PSP, CBD, and MSA-P, significant regions of atrophy unique to each disorder were identified, including (1) the superior parietal lobule in CBD (2) putamen in MSA-P (3) insula and medial dorsal nucleus in PSP.ConclusionOur results suggest that there are characteristic patterns of atrophy in APS. Guided by these findings, future studies on the individual subject level may lead to the development of robust imaging biomarkers.

Diagnosis of multiple system atrophy

“…Moreover, specific longitudinal changes in MSA (early atrophy of basal ganglia followed by late cortical atrophy) have been identified with this technique (Brenneis et al, 2007). Other findings, such as degeneration of the ponto-cerebellar tract and white matter abnormalities in specific areas have been identified using VBM (Minnerop et al, 2007; Yu et al, 2015). Cognitive impairment in MSA is also associated with specific VBM changes (Fiorenzato et al, 2017).…”

Neuroimaging of Parkinson's disease: Expanding views

“…They have also involved an expanding list of advanced MRI methods, such as T2, T2*, susceptibility weighted imaging, magnetization transfer, neuromelanin sensitive imaging, etc., to image the substantia nigra and midbrain with sufficient detail to discriminate pathological changes of PD. A meta-analysis of 39 voxel-based morphometry studies of PD, MSA-P, CBD, and PSP has indicated that there are patterns of atrophy that can differentiate these disorders from each other (Yu et al, 2015). Other recent structural MRI studies not included in this meta-analysis were a volumetric study of the midbrain tegmentum to differentiate PD versus PSP (Kim et al, 2015); a support vector machine learning algorithm for classification of PD, PSP, and healthy controls using T1-weighted MRI (Salvatore et al, 2014); and susceptibility weighted imaging of the putamen to differentiate PD and MSA-P (Yoon et al, 2015).…”

Neurodegeneration and the Cerebellum

“…It presents with α-synuclein glial inclusions and gray matter atrophy in several cerebral areas, including the superior cerebellum [80]. There are 2 subtypes of MSA, MSA-P (parkinsonism) and MSA-C (cerebellar), as well as 2 clinical MSA phenotypes, OPCA (olivopontocerebellar atrophy) and SND (striatonigral degeneration).…”

“…Corticobasal (ganglionic) degeneration (CBD) is a neurodegenerative tauopathy that manifests as asymmetric motor and cortical sensory dysfunction [80]. Neural degeneration is prominent and well described in the substantia nigra and STN [83], but cerebellar involvement has also started to be explored.…”

“…Progressive supranuclear palsy (PSP) is a neurodegenerative tauopathy that clinically presents as vertical gaze palsy, bradykinesia, dementia, and postural instability [80]. PSP shares many characteristics with PD, such as reduced functional activity of the basal ganglia and cortical motor areas.…”