Two recent publications highlight results from a study funded by the United Kingdom’s National Health Service (NHS) with the goal of identifying strategies to increase the capacity of medical retina clinics. The NHS conducted the study, called EMERALD (Effectiveness of Multimodal imaging for the Evaluation of Retinal Edema and new vessels in Diabetic Retinopathy), in response to what the agency called an “urgent need” to decrease the burden created by the increasing prevalence of diabetes and new indications for aVEGF treatment for diabetic macular edema (DME) and proliferative diabetic retinopathy (PDR) which require frequent visits in a large, growing, and relatively young population. Overburdened clinics result in delays in the evaluation and treatment of patients and, consequently, to poor visual outcomes.
The current standard of care for the evaluation of DME and PDR is an ophthalmologist examining patients in clinic (slit-lamp exam and SD-OCT for DME; slit-lamp exam for PDR). The EMERALD study evaluated the diagnostic accuracy, cost-effectiveness, and acceptability of multimodal imaging reviewed by certified ophthalmic graders for surveillance of patients with stable DME or PDR. Investigators used SD-OCT for DME and seven-standard field (7SF) ETDRS and UWF fundus images to detect PDR.
Under the main analysis of DME (grader referring a patient to ophthalmologists due to presence of active DME or unsure or ungradable), graders had a sensitivity of 97% with a specificity of 31%. Under the main analysis of PDR (grader referring patients to Ophthalmologists due to presence of active PDR or unsure or ungradable), graders had similar sensitivity and specificity whether they used 7SF ETDRS (sensitivity 85%; specificity 48%) or UWF (sensitivity 83%; specificity 54%). UWF imaging had a slightly higher sensitivity to detect PDR with pre-retinal/vitreous hemorrhage (high-risk) and was less costly than 7SF ETDRS. Therefore, investigators considered it the preferred option. optomap UWF images also required less time for both capture and reading vs. 7SFs; allowing clinics to evaluate more patients faster without sacrificing clinical accuracy, and redirect time to the evaluation of people at high risk of visual loss.
References:
- Lois N, Cook J, Wang A, Aldington S, Mistry H, Maredza M, et al. Multimodal imaging interpreted by graders to detect re-activation of diabetic eye disease in previously treated patients: the EMERALD diagnostic accuracy study. Health Technol Assess 2021;25(32). link
- Maredza M, Mistry H, Lois N, et al. Br J Ophthalmol Epub ahead of print: [3 June 2021]. link