Name : Morteza
Family : Sanei Taheri
Affiliation :Radiology Department,Shohada Tajrish Hospital,SBMU
Academic Degree : Associate Professor of Radiology
Resident : Afarin sadeghian
Gender : Male
Age : 58
58-year-old patient with ataxia from 3 years ago
The imagings show cerebellum with normal structure in a posterior fossa with normal size which displays enlarged fissures(interfolial spaces) in comparison to the foliae,secoundry to loss of tissue.Middle cerebellar peduncle width is smaller than normal.Volume loss of pons,more in ventral part(olivery eminences),with pontine cruciform hyperintensity on T2 and FLAIR sequences due to selective degeneration of pontocerebellar tracts( hot cross bun sign)(fig.2,3) are seen.Some degrees of midbrain atrophy as reduction of AP midbrain diameter(penguin or hummingbird sign)(fig.9) and midbrain tectum atrophy(mickey mouse sign)(fig.5) are also noted.
The DDx of cerebellar atrophy:1.PSP(Progressive Supranuclear Pulsy),2.PD(Parkinson Disease),3.MSA(Multiple-System Atrophy) of striatonigral type The average MCP(Middle cerebellar peduncle) is significantly smaller in patients with MSA than those with PD. The DDx of “hot cross bun” sign:1. Multiple-system atrophy, 2.Spinocerebellar atrophy types 2 and 3,3.Parkinsonism secondary to vasculitis,4. Variant Creutzfeldt-Jakob disease (vCJD) The DDx of midbrain atrophy:1.PSP,2.PD,3.MSA,4.Corticobasal degeneration
Discussion (Related Text)
MSA is a neurodegenerative disorder that involves, to varying degrees, the basal ganglia, the olivopontocerebellar complex and the autonomic system. MSA is synonymous with striatonigral degeneration when parkinsonism predominates (MSA-p), with olivoponto cerebellar atrophy (OPCA) when MSA-c signs predominate, and with Shy-Drager syndrome when autonomic failure is dominant. In MSA-p, the degenerative changes predominantly affect the basal ganglia, particularly the putamen. On T2-weighted MR images, a hyperintense rim at the putaminal edge, putaminal atrophy, and intrinsic signal intensity change are seen. In MSA-c, the changes predominantly affect the infratentorial structures. On T2-weighted MR images, atrophy and increased signal intensity within the pons, cerebellum, and middle cerebellar peduncles are seen.Over the last few years a number of MRI studies have been focused on the identification of diagnostic markers helpful in the differential diagnosis of parkinsonian syndromes such as MSA, PSP and Parkinson’s disease. In the present DWI study we show that ADC values are increased in the MCP of MSA-P patients and that ADC measurement of MCP can distinguish PSP and Parkinson’s disease from MSA-P patients with 100% sensitivity and 100% specificity.
Radiology 2007; 245:606–607