Characteristics of MRI Phase Congruency Texture in Limbic Brain Regions relates to Depression in People with Comorbid MS

Motivation: Depression affects 50% of individuals with multiple sclerosis (MS) in their lifetime but mechanisms remain poorly understood. Goal(s): To investigate the nature and relationship of subtle structural changes in depression-related brain areas in MS using phase congruency texture analysis. Approach: Sum of phase congruency (sPC) and weighted mean phase (WMP) were calculated in the thalamus, hippocampus, and amygdala. These measures alongside lesion volumes were assessed as regressors of Beck's Depression Inventory scores in MS. Results: FLAIR sPC and T2 WMP were compromised in MS. The thalamic sPC in FLAIR and sPC in T2 explained the greatest variance in BDI. Impact: Non-invasive measurement of subtle structural changes in depression-relevant brain gray matter may be invaluable for improving our understanding of the underlying mechanisms in people with comorbid MS and depression, encouraging further investigations of MRI phase congruency analyses.