Aberrant white-gray matter functional coupling in rhegmatogenous retinal detachment: evidence from resting-state functional MRI and machine learning.

Background: Emerging evidence suggests that blood-oxygen-level-dependent signals in white matter reflect functional activity; however, it remains unclear whether white matter function is altered in rhegmatogenous retinal detachment (RRD) and how it interacts with gray matter.

Methods: We conducted resting-state functional MRI analyses in patients with RRD and healthy controls to investigate regional white matter activity using amplitude of low-frequency fluctuations/fractional ALFF (ALFF/fALFF), and cross-tissue white matter-gray matter functional connectivity. Voxel-wise analyses were performed to identify aberrant white matter regions, and seed-based connectivity mapping was applied using affected white matter tracts. Support vector machine models were constructed to evaluate the diagnostic utility of these functional features.

Results: Patients with RRD exhibited significantly increased ALFF/fALFF in key projection fibers, including the bilateral anterior corona radiata (ACR) and anterior limb of the internal capsule (ALIC). Enhanced functional connectivity was observed between the left ACR and nonvisual gray matter regions such as the right middle temporal gyrus and medial orbitofrontal cortex. Among all features, the fALFF value of the left ALIC demonstrated the highest classification performance (area under the curve = 0.8974) in distinguishing RRD from healthy controls.

Conclusion: These findings reveal aberrant spontaneous low-frequency oscillatory activity and enhanced white matter-gray matter coupling in patients with RRD, reflecting cross-tissue functional reorganization beyond the retina. Notably, the elevated fALFF signal in the left ALIC demonstrates strong potential as a neuroimaging biomarker. This study underscores the value of white matter functional metrics in characterizing central nervous system alterations in RRD and offers novel insights into its neurobiological underpinnings.