Diabetic Retinopathy Progression, Macular Edema Predicted by Choroidal Parameters

OCT Scan
OCT scan of section through the retina.
Researchers examine the role of various choroidal vascular parameters in predicting diabetic retinopathy and diabetic macular edema.

Choriocapillaris (CC) flow deficit percentage (CC FD%) may improve the prediction of diabetic retinopathy (DR) progression and diabetic macular edema (DME) development, according to research published in the American Journal of Ophthalmology.

Researchers recruited 946 participants (eyes, 1879; mean age, 64.08±7.69 years; 60.4% women) with type 2 diabetes who either did not have diabetic retinopathy (DR) or had mild nonproliferative DR for the community-based, prospective cohort study. Patients underwent comprehensive ophthalmic examinations, which included swept-source optical coherence tomography angiography, annually over 3 consecutive years. The primary endpoints were DR progression and DME occurrence.

Overall, 16.60% of eyes experienced DR progression and 6.12% had DME onset at the study conclusion.

Multivariate model analysis revealed that DR progression was associated with lower  superficial capillary plexus (SCP) vessel density, lower SCP perfusion density, lower radial peripapillary capillary (RPC) vessel density, and elevated CC FD% (Relative Risk (RR) per standard deviation (SD) decrease, 1.30; 1.41; 1.23; and 1.62, respectively; P ≤.002 for all).

DME occurrence was also associated with elevated CC FD% (RR, 1.29 per SD increase; P <.001), lower SCP perfusion density  (RR, 1.29 per SD increase; P =.016), and lower SCP vessel density (RR, 1.35 per SD increase; P =.005).

Incorporating CC FD% improved the power to predict DR progression (change in C-statistic, 0.036; P =.002) and DME development (change in C-statistic, 0.029; P <.001), according to the report. Compared with established risk factors alone, CC FD% better predicted DR progression (area under the curve [AUC], 0.656 vs 0.692; P =.002) and DME development (AUC, 0.757 vs 0.786; P <.001).

“We found that peripapillary CC microcirculatory alterations have additional predictive value for predicting DR progression and development of DME, which is worth consideration for the development of public health policy and management of clinical DM,” according to the researchers. 

Study limitations include a single center design and short study duration.


Guo X, Chen Y, Bulloch G, et al. Parapapillary choroidal microvasculature predicts diabetic retinopathy progression and diabetic macular edema development: a three-year prospective study. Am J Ophthalmol. Published online July, 18 2022. doi:10.1016/j.ajo.2022.07.008