Structural atrophy and functional disturbance in the thalamic nuclei of patients with amyotrophic lateral sclerosis.

Objective: This study investigated the structural and functional impairments in thalamic nuclei in amyotrophic lateral sclerosis (ALS) and evaluated their associations with disease severity and diagnostic value.

Methods: This study was conducted on T1-weighted and resting-state functional magnetic resonance images from 71 ALS patients and 61 healthy controls. In each hemisphere, the thalamus was parcellated into 25 nuclei and subsequently grouped into 6 subregions. The volume and amplitude of low-frequency fluctuation (ALFF, reflecting spontaneous neural activity) in each thalamic subregion were measured and compared between groups. These metrics were then used for correlation and diagnostic analyses.

Results: A volumetric reduction was observed in the bilateral anterior, intralaminar, ventral, and left medial thalamic subregions in the ALS patients (FWE-corrected P < 0.05). A decreased ALFF was observed in the right anterior and ventral thalamic subregions of patients with ALS (FWE-corrected P < 0.05). The volumes of the bilateral intralaminar (left: r = 0.304, P = 0.011; right: r = 0.281, P = 0.018) and ventral (left: r = 0.355, P = 0.003; right: r = 0.335, P = 0.005) thalamic subregions were correlated with disease severity. Compared with the whole-thalamic measurements, the volumetric and ALFF measurements of thalamic subregion demonstrated greater diagnostic performance. The combined volumetric and ALFF measurements in the thalamic subregions further resulted in a significantly increased AUC (0.865, P < 0.001).

Conclusions: Selective structural and functional damage to thalamic subregions is a feature of ALS and could potentially contribute to future diagnostic approaches and assessments of disease severity.