A 60-year-old diabetic has center-involving diabetic macular edema treated with monthly anti-VEGF injections. Baseline optical coherence tomography shows intact inner segment-outer segment (ellipsoid) line beneath the fovea. Another patient with identical macular thickness shows complete disruption of the ellipsoid zone. How does this difference affect prognosis?
- A Disruption of the ellipsoid zone predicts poorer final visual acuity despite anatomical resolution of edema ✓
- B Both patients have identical visual prognosis regardless of ellipsoid zone status
- C Ellipsoid zone disruption predicts better response because damaged tissue regenerates faster
- D Ellipsoid zone status matters only in retinal vein occlusion, not in diabetes
Correct answer: A. Disruption of the ellipsoid zone predicts poorer final visual acuity despite anatomical resolution of edema
Explanation
Integrity of the ellipsoid zone (inner segment-outer segment junction) on OCT reflects photoreceptor health and is one of the strongest structural predictors of final visual acuity in diabetic macular edema. Eyes with disrupted ellipsoid zone achieve poorer vision even when the edema resolves completely, because outer retinal damage is often irreversible. Central macular thickness alone correlates poorly with visual outcome once chronicity sets in.
Reference: Ryan's Retina, 6th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.