Sight-threatening signs of diabetic retinopathy include macular oedema, retinal or optic disc new vessels, and vitreous haemorrhage.
Main measures to prevent visual loss include improvement in glycaemic, lipid, and hypertensive control, and the identification of sight-threatening disease before visual loss occurs.
Main therapies are intravitreal injection of anti-vascular endothelial growth factor (VEGF) agents, macular and pan-retinal laser photocoagulation, and vitrectomy surgery. Intravitreal corticosteroid therapy may be considered for patients refractory to anti-VEGF.
Diabetic retinopathy is the retinal consequence of chronic progressive diabetic microvascular leakage and occlusion. It eventually occurs to some degree in all patients with diabetes mellitus. There are two types: non-proliferative and proliferative. Non-proliferative diabetic retinopathy (NPDR) is the early stage of the disease and is less severe. Blood vessels in the eye may leak fluid into the retina, which leads to blurred vision. Proliferative diabetic retinopathy (PDR) is the more advanced form of the disease. New blood vessels start to grow in the eye (neovascularisation), which are fragile and can haemorrhage. This may cause vision loss and scarring of the retina.
History and exam
Key diagnostic factors
Other diagnostic factors
- cotton wool spots
- intraretinal haemorrhage
- lipid exudates
- macular thickening
- vision loss
- venous beading
- intraretinal microvascular abnormalities
- optic disc neovascularisation
- retinal neovascularisation
- pre-retinal or vitreous haemorrhage
- retinal detachment
- young-onset diabetes
- longer duration of diabetes
- poor glycaemic control
- renal disease
- Pima Indians
- cataract surgery
- elevated lipid levels
1st investigations to order
- photographs of the fundus
- optical coherence tomography scanning
- fluorescein angiography
- B scan ultrasonography
PDR: high-risk/iris neovascularisation
Jonathan Dowler, MD, FRCS, FRCOphth
Consultant Ophthalmic Surgeon
The London Clinic
JD declares that he has no competing interests.
Dr Jonathan Dowler would like to gratefully acknowledge Dr Robin Hamilton, a previous contributor to this monograph. RH declares that he has no competing interests.
Zachary Bloomgarden, MD
Diabetes and Bone Disease
Mount Sinai School of Medicine
ZB declares that he has no competing interests.
Tien Y. Wong, MD, MPH, PhD
Head of Department of Ophthalmology
University of Melbourne
TYW declares that he has no competing interests.
Stephen Schwartz, MD
Bascom Palmer Eye Institute
Within the last 5 years, SS has received funding for organizing continuing medical education conferences from Alcon, Genentech, and Novartis; has owned shares in Pfizer; has received research funding from Genentech; and is co-holder of a patent pending on "Molecular targets for modulating intraocular pressure and differentiation of steroid responders versus nonresponders.
- Ocular ischaemic syndrome
- Radiation retinopathy
- Retinal venous occlusion
- Type 2 diabetes in adults: management
- Standards of medical care in diabetes - 2022
Diabetes type 2: should I take insulin?
Diabetes type 2: what treatments work?More Patient leaflets
- Log in or subscribe to access all of BMJ Best Practice
Use of this content is subject to our disclaimer