SD-OCT is the standard for identifying macular pathology, yet color fundus photography remains the dominant imaging method in ocular telehealth programs. New research presented during ARVO’s recent virtual meeting suggests macular SD-OCT should be part of teleophthalmology visits when assessing diabetic retinopathy, as it increased macular pathology diagnoses by 62% while reducing false positives.

“Even with the use of ultra-widefield (UWF) imaging modalities, potentially eyes with visually significant macular pathology are not readily identified without SD-OCT,” the researchers wrote in their paper.

SD-OCT identified 36% of DME- and 53% of epiretinal membrane (ERM)-referable cases. Only about 27% of eyes with centrally involved DME and roughly 3% with ERM seen on SD-OCT were identified on UWF imaging.

The study included 422 eyes of 211 diabetic patients. The investigation evaluated consecutively imaged patients over a two-month period at a UWF image-based DR teleophthalmology program that used a Monaco device (Optos).

Both UWF photos and SD-OCT images were acquired using the same instrument at the same session. Mask graders evaluated the UWF photos and OCT images for DR and DME. Since OCT measures weren’t currently available through the Monaco, the SD-OCT scans were evaluated qualitatively for macular pathology, including DME, ERM, pigment epithelial detachment, neovascular macular degeneration and tractional retinal detachment. SD-OCT was used as the gold standard to calculate reliability.

Specific findings included:

• UWF grading severity for diabetic retinopathies: No DR: 57.8%, mild nonproliferative DR: 30.3%, moderate nonproliferative DR: 7.1%, severe nonproliferative DR: 1.7%, proliferative DR: 2.4%, ungradable: 0.7%.
• UWF grading severity for DME: DME: 93.4%, non-centrally involved DME: 5.2%, centrally involved: DME 0.7%, ungradable: 0.7%.
• SD-OCT was ungradable in 0.5% of cases.
• SD-OCT identified five (25%) non-centrally involved DME, nine centrally involved DME (75%) and 28 (97%) ERM eyes that were undetected on UWF.
• SD-OCT did not find 14 (56%) non-centrally involved DME, two centrally involved DME (67%) and nine (90%) ERM eyes identified on UWF.

Given the reduced effort, compact footprint and reduced overall cost of integrated SD-OCT/UWF devices, their use in large DR screening programs could substantially improve disease identification and improve visual outcomes, the investigators said.