Chronic Hyperglycemia Damages Retinal Capillaries
Placeholder: sustained high glucose injures small vessel walls.
- HbA1c: Trigger (Chronic glucose exposure)
- Endothelium: Target (Capillary wall cells)
- Years: Onset (Cumulative damage)
- Duration: Risk driver (Longer disease, more harm)
Vascular injury mechanism
Placeholder: hyperglycemia thickens basement membranes and weakens pericytes.
Placeholder: better glycemic control slows early capillary injury.
Capillary Walls Become Increasingly Permeable
Placeholder: tight junctions loosen, letting fluid escape vessels.
- Loosened: Junctions (Tight junction breakdown)
- Weakened: Barrier (Blood-retinal barrier)
- VEGF: Mediator (Vascular permeability factor)
- Rising: Trend (With poor HbA1c control)
Permeability escalation
Placeholder: VEGF upregulation drives progressive vessel leakiness.
Placeholder: permeability rises faster with higher HbA1c.
Plasma Fluid Leaks Toward the Macula
Placeholder: leaking capillaries send fluid into central retina.
- Centripetal: Direction (Toward macula)
- Plasma: Carrier (Protein-rich fluid)
- Macula: Location (Central vision zone)
- Progressive: Pace (Accumulates over time)
Fluid migration
Placeholder: leaked fluid diffuses through retinal layers toward fovea.
Placeholder: fluid accumulation tracks glycemic control closely.
Fluid Pools Into Macular Cysts
Placeholder: pooled fluid forms cystic spaces, thickening the macula.
- Cysts: Structure (Fluid-filled pockets)
- ~250 μm: Normal OCT (Baseline macular thickness)
- >400 μm: Edema OCT (Clinically significant edema)
- OCT scan: Detection (Cross-section imaging)
Edema formation
Placeholder: cystoid spaces form between retinal layers as fluid pools.
Placeholder: macular thickness rises sharply once cysts form.
Swollen Macula Distorts Central Vision
Placeholder: thickened macula blurs and warps fine central detail.
- Blur: Symptom (Central visual field)
- Metamorphopsia: Symptom (Line distortion)
- HbA1c + years: Severity link (Combined risk factors)
- Glycemic control: Management (Slows progression)
Visual consequence
Placeholder: distorted photoreceptor alignment degrades central acuity.
Placeholder: early control of HbA1c preserves central vision longest.