Duration-Dependent Decoupling of the Macular Neurovascular Unit in Type 2 Diabetes Without Retinopathy: A Topographic Analysis Using Ultra-Widefield OCT Angiography.

Longer duration was associated with progressive ganglion cell-inner plexiform layer thinning and deep-predominant deep vascular density reduction across nearly all macular zones (q<0.05); the deep vascular density deficit was most pronounced in the outer ring.

Superficial vascular density showed nasal-temporal asymmetry; selective nasal inner loss in ≥10-year group.

GCIPL-DVD coupling, present in controls, attenuated in ≥10-year group, indicating neurovascular unit decoupling.

Duration independently predicted ganglion cell-inner plexiform layer (β=-0.21) and deep vascular density (β=-0.27) after adjustment (P<0.01).