Magnetic resonance imaging abnormalities as a marker of multiple system atrophy in isolated rapid eye movement sleep...

Area of Science:

• Neurology
• Radiology
• Sleep Medicine

Background:

• Patients with isolated rapid eye movement sleep behavior disorder (IRBD) have a high risk of developing neurodegenerative diseases such as Parkinson disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA).
• Specific neuroimaging findings on magnetic resonance imaging (MRI) are characteristic of manifest MSA, involving abnormalities in the putamen, cerebellum, and brainstem.

Purpose of the Study:

• To evaluate the utility of conventional brain MRI in detecting specific abnormalities in IRBD patients.
• To determine if these MRI findings can predict the future development of MSA, distinguishing it from PD and DLB.

Main Methods:

• Retrospective analysis of MRI scans from 61 IRBD patients who later developed PD, DLB, or MSA.
• Comparison of the frequency of MSA-specific MRI changes (e.g., hot cross-bun sign, putaminal rim, cerebellar atrophy) among patient groups.
• Assessment of the predictive value of these MRI changes for MSA conversion.

Main Results:

• MRI changes typical of MSA were identified in 80% of patients who converted to MSA (4 out of 5).
• These specific MRI changes were found in only 5.4% of patients who developed PD or DLB (3 out of 56).
• The MRI findings demonstrated high sensitivity (80.0%) and specificity (94.6%) for predicting MSA development.

Conclusions:

• Conventional brain MRI is a valuable tool for predicting the conversion to MSA in patients with IRBD.
• Characteristic MRI abnormalities associated with manifest MSA can be detected during its premotor stage, aiding in early diagnosis and prediction.