Brain Morphological Alterations in Adults with Spinal Muscular Atrophy Types 2 and 3: A CAT12-Derived Region-Based...

Area of Science:

• Neuroscience
• Neurology
• Medical Imaging

Background:

• Spinal muscular atrophy (SMA) types 2 and 3 are increasingly recognized as multisystem disorders.
• Central nervous system involvement in adult SMA patients requires further characterization.
• Brain structural alterations in adults with SMA are not well understood.

Purpose of the Study:

• To assess brain morphology in adult patients with SMA types 2 and 3.
• To utilize Computational Anatomy Toolbox 12 (CAT12) for region-based and surface-based morphometry.
• To identify specific patterns of brain structural changes in adult SMA.

Main Methods:

• Included 27 adult patients with SMA types 2 and 3 and 27 matched healthy controls.
• Utilized MRI scans acquired before or early in nusinersen treatment.
• Applied CAT12 for region-based morphometry and surface-based morphometry analysis.
• Corrected for multiple comparisons using the Benjamini-Hochberg false discovery rate.

Main Results:

• Significant reduction in left thalamus grey matter volume in SMA patients compared to controls.
• Increased sulcal depth in the left orbital sulcus was the sole significant cortical finding post-correction.
• Other cortical differences (thickness, sulcal depth) were not statistically significant after correction.

Conclusions:

• Adults with SMA types 2 and 3 exhibit specific brain structural alterations.
• Findings include reduced left thalamus grey matter and increased left orbital sulcus depth.
• These results support the concept of SMA as a multisystem disorder affecting the central nervous system.