Ophthopedia: OCT layers predict DME response

A scoping review published in *Survey of Ophthalmology* on May 22 examined whether two optical coherence tomography findings — disorganization of retinal inner layers, or DRIL, and disruption of retinal outer layers — can predict how eyes with diabetic macular edema respond to anti-VEGF therapy. The review said the literature points to both markers as signals of variable treatment response, including differences in retinal anatomy after injections and in visual acuity outcomes. The paper arrives as retina clinics continue to use OCT not only to confirm edema, but to decide whether repeated injections are likely to deliver meaningful gains. ### What exactly did the review look at? The authors said they used a scoping review framework to give “a broad overview” of the role of DRIL versus disruption of retinal outer layers in predicting anti-VEGF response in diabetic macular edema. The article was published online in *Survey of Ophthalmology* and mirrored on ScienceDirect on May 22, 2026. The review’s framing matters because DRIL and outer retinal disruption are not new observations on OCT. (surveyophthalmol.com) What the authors set out to do was organize how those findings have been used across studies as prognostic markers before and during treatment, rather than test a new drug or a single retreatment protocol. ### Why do DRIL and outer retinal defects draw so much attention? DRIL refers to loss of clear boundaries among the inner retinal layers on OCT, while outer retinal disruption generally points to damage involving structures such as the ellipsoid zone or external limiting membrane. (surveyophthalmol.com) Prior literature has linked both categories of abnormalities to worse visual function in diabetic macular edema and diabetic retinopathy. A 2025 systematic review and meta-analysis summarized by *Ophthalmology Advisor* found that disrupted ellipsoid zone or external limiting membrane and DRIL were associated with poorer visual outcomes at 6 and 12 months in center-involving diabetic macular edema. That analysis reported effect sizes of about 9.7 fewer ETDRS letters for disrupted EZ/ELM and 6.0 fewer letters for DRIL at 6 months. (retinatoday.com) ### What does this add for anti-VEGF treatment decisions? The new scoping review pulls together evidence that these layer-level OCT changes may help explain why some eyes dry out anatomically but do not gain much vision, while others show limited anatomic response from the outset. That is the practical question anti-VEGF clinics face when deciding whether to continue, extend, or reconsider a regimen after the loading phase. (ophthalmologyadvisor.com) A separate 2025 report in *Retinal Physician*, citing a British Journal of Ophthalmology study, described baseline OCT biomarkers associated with switching away from anti-VEGF in 275 eyes with diabetic macular edema. That report listed DRIL and disorganization of outer layers among the evaluated markers, though other features such as subretinal fluid, hyperreflective cystoid walls and vitreomacular interface abnormalities showed the strongest associations with switching. (surveyophthalmol.com) ### Does this mean OCT can now tell doctors who will fail treatment? The evidence does not support a single yes-or-no OCT rule. The available studies instead suggest that DRIL and outer retinal disruption are part of a broader prognostic picture that includes baseline vision, central retinal thickness, fluid pattern and follow-up interval. The review’s value is that it narrows attention to biomarkers already visible on routine scans. (retinalphysician.com) In high-volume diabetic retina practice, that could make these findings useful for triage, expectation-setting and earlier discussion of alternative strategies when repeated anti-VEGF injections are producing limited gains, according to the published literature the review maps. ### What should readers watch next? (ophthalmologyadvisor.com) The next step is likely to be prospective validation and more standardized grading of DRIL and outer retinal disruption across devices and readers. A 2022 reliability study in OCT grading showed that subjective assessment of DRIL and disorganization of outer retinal layers can be challenging in routine practice, a point that matters if clinics want to use these markers consistently. (surveyophthalmol.com) The May 22 *Survey of Ophthalmology* paper is now the main reference point for that discussion, and the full review on the journal and ScienceDirect sites lays out the studies behind the proposed OCT-based predictors. (surveyophthalmol.com) (pmc.ncbi.nlm.nih.gov)