Multiple system atrophy
Citation, DOI & article data
Multiple system atrophy (MSA) is a sporadic neurodegenerative disease (one of the synucleinopathies) characterized by varying degrees of cerebellar ataxia, autonomic dysfunction, parkinsonism, and corticospinal dysfunction.
Multiple systemic atrophy is a sporadic disease, with a prevalence of 4 per 100,000 2. Symptoms typically begin between 40 and 60 years of age 2.
Clinical presentation is variable, but the disease typically presents in one of three patterns (initially described as separate entities) 1,2:
- Shy-Drager syndrome is used when autonomic symptoms predominate
- striatonigral degeneration shows predominant parkinsonian features
- olivopontocerebellar atrophy demonstrates primarily cerebellar dysfunction
In a 2007 consensus paper 6, multiple system atrophy (MSA) was divided clinically into two forms, according to the dominant non-autonomic symptoms:
- MSA-C: predominance of cerebellar symptoms (olivopontocerebellar atrophy)
- MSA-P: predominance of parkinsonian signs and symptoms (striatonigral degeneration)
Some older texts refer to MSA-A (where A stood for autonomic) to denote Shy-Drager syndrome. In the latest consensus, however, autonomic symptoms are considered part of both MSA-C and MSA-P, thus the term MSA-A is no longer used.
Like other synucleinopathies, multiple systemic atrophy results from abnormalities of alpha-synuclein metabolism, resulting in intracellular deposition. Unlike Parkinson disease and Lewy body dementia (two other synucleinopathies), these intracellular deposits are found not only in neurons but also in oligodendroglia 2.
MRI is the modality of choice for imaging patients with suspected multiple system atrophy (MSA).
- T2 hyperintensities in the pontocerebellar tracts
- abnormal putaminal signal (in MSA-P) 5:
- disproportionate atrophy
- MSA-C: in cerebellum and brainstem (especially olivary nuclei and middle cerebellar peduncles)
- MSA-P: in putamen
diffusion tensor imaging
- ADC: higher in the pons, cerebellum, and putamen compared with Parkinson disease or controls
- fractional anisotropy (FA): lower in the pons, cerebellum, and putamen compared with Parkinson disease or controls
On SPECT/CT with I-123 ioflupane, there is loss of the normal comma- or crescent-shaped tracer uptake in the striatum. Instead, a period- or oval-shaped uptake is seen within the caudate nucleus head, without tracer uptake in the putamen. Quantitative assessment reveals reduced uptake in the putamen compared with norms.
Treatment and prognosis
Unfortunately, no effective treatment is currently available. The disease progresses relentlessly, culminating in death, usually within 10 years of diagnosis 2.
- 1. Robert I. Grossman, David M. Yousem. Neuroradiology. (2003) ISBN: 9780323005081 - Google Books
- 2. Valery N. Kornienko, I.N. Pronin. Diagnostic Neuroradiology. (2008) ISBN: 9783540756521 - Google Books
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- 7. Lee W, Lee C, Shyu W, Chong P, Lin S. Hyperintense Putaminal Rim Sign is Not a Hallmark of Multiple System Atrophy at 3T. AJNR Am J Neuroradiol. 2005;26(9):2238-42. PMC7976126 - Pubmed
- 8. Naka H, Ohshita T, Murata Y, Imon Y, Mimori Y, Nakamura S. Characteristic MRI Findings in Multiple System Atrophy: Comparison of the Three Subtypes. Neuroradiology. 2002;44(3):204-9. doi:10.1007/s00234-001-0713-7 - Pubmed
- 9. Vijayan J, Sinha S, Ravishankar S, Taly A. MR Imaging in Multiple System Atrophy: Its Role in "Splitting" Parkinsonism. Ann Indian Acad Neurol. 2008;11(4):257-8. doi:10.4103/0972-2327.44565 - Pubmed