Characteristics of striatal changes in diabetic retinopathy and type 2 diabetes: a resting-state functional magnetic resonance imaging study

The presence of reward-related neural deficits in type 2 diabetes mellitus (T2DM) and its microvascular complications has been linked to abnormal striatal function. However, differences in striatal whole-brain functional connectivity (FC) between patients with diabetic retinopathy (DR) and those with T2DM without retinopathy remain unclear. In this study, 30 patients with DR, 30 with T2DM, and 29 healthy controls (HCs) were recruited. A seed-based FC approach was employed to analyze alterations across six predefined striatal subregions among the three groups and to examine correlations between abnormal FC patterns and clinical cognitive performance. Results revealed that, compared with the T2DM group, the DR group exhibited reduced FC between several striatal subregions and key nodes within the salience, cognitive control, visual, reward, and sensorimotor networks. Notably, in the DR group, MoCA scores showed a positive correlation with FC between the right dorsal rostral putamen and the left insula. These findings provide novel evidence for distinct striatal circuit alterations in DR and may contribute to identifying neuroimaging markers for its early detection and intervention.