Overview

The term "non-proliferative diabetic retinopathy" (NPDR) is used when a patient with diabetes has funduscopic signs including one or more of the following lesions (in the absence of neovascularisation or pre-retinal/vitreous haemorrhage): microaneurysms, intraretinal (dot/blot/flame) haemorrhages, cotton wool spots, intraretinal microvascular abnormalities (IRMA) and/or venous beading.

Within this general classification, sub-classifications exist that reflect the relative severity of the retinal changes and correlate with the risk of vision loss.

Using the International Clinical Diabetic Retinopathy Severity Scale, the levels of NPDR are as follows:
- Mild NPDR: presence of microaneurysms only.
- Moderate NPDR: more changes than just microaneurysms, but the criteria for severe NPDR (below) is not met.
- Severe NPDR (4-2-1 rule): any of the following changes WITHOUT any signs of proliferative diabetic retinopathy:
1. More than 20 intraretinal haemorrhages in each of the four quadrants
2. Definite venous beading in 2 or more quadrants
3. Prominent IRMA in 1 or more quadrant

It is important to note that macular oedema may be present at any stage of diabetic retinopathy, from mild NPDR through to PDR. The grading of macular oedema is discussed in further detail elsewhere in this Atlas (please click the link at the bottom of this page).

Some examples of each stage of NPDR are below.

Case Examples

Differential Diagnosis

References

Alam, M, Zhang, Y, Lim, JI, Chan, R. Yang, M, Yao, X, (2020) Quantative optical coherence tomorgraphy angiography features for objective classification and staging of diabetic retinopathy. Retina: February 2020 - Volume 40 - Issue 2 - p 322-332

Duh, E. J., Sun, J. K., & Stitt, A. W. (2017). Diabetic retinopathy: current understanding, mechanisms, and treatment strategies. JCI insight, 2(14).

Proposed international clinical diabetic retinopathy and diabetic macular edema disease severity scales. Ophthalmology, Volume 110, Issue 9 - p 1677-1682

Johannesen, SK., Viken, JN., Vergmann, AS. and Grauslund, J. (2019), Optical coherence tomography angiography and microvascular changes in diabetic retinopathy: a systematic review. Acta Ophthalmol, 97: 7-14.

Tran, K. Pakzad-Vaezi, K (2018) Multimodal imaging of diabetic retinopathy, Current Opinion in Ophthalmology: November - Volume