Retina 1Diabetic RetinopathyProf K N Jha, MSEmail: kirtinath.jha@gmail.com

Learning Aim•Retina: Retinal topography, and Histology

•Clinical features of diabetic retinopathy

•Diabetic retinopathy and visual impairment

•Treatment of diabetic retinopathy

•Prevention of visual impairment and blindness due to diabetic retinopathy.

Development of Retina

RPE

Neurosensory retina

Subretinal space

Normal Fundus: Retinal Topography

Retina: Schematic Diagram

Diabetic RetinopathyGlobally , diabetic retinopathy accounts for about 1 % of blindness. In India, diabetic retinopathy accounts for about 0.1 % of blindness.

Diabetic Retinopathy• The best predictor of diabetic retinopathy is the

duration of the disease.

• Type I diabetes The first 5 years of type 1

diabetes has a very low risk of retinopathy. All

patients develop retinopathy in 15 years.

• Type II diabetes: Risk of retinopathy increases

with duration of diabetes , hypertension and

smoking, and renal pathology.

Diabetic RetinopathyRisk factors:

• Diabetic age and age of the patient• Glycemic control• Hypertension• Poor renal status• Smoking• Pregnancy, obesity, hyperlipidemia,

anemia

Pathogenesis DR is predominantly a microangiopathy

resulting from hyperglycemia.

Vascular Endothelial Growth Factor (VEGF)

appears to be of particular importance in

development of proliferative changes .

Pathogenesis Capillaropathy: loss of pericytes,

thickening of basement membrane , and

proliferation of endothelium.

Haematological changes

Microvascular occlusion leading to

hypoxia

Pathogenesis

Consequences of chronic leakage

Consequences of retinal ischaemia

Types

● Non-Proliferative Diabetic Retinopathy(NPDR)/background diabetic

retinopathy ( BDR)

● Proliferative Diabetic Retinopathy(PDR)

Clinical Features•Asymptomatic in the beginning

•Symptoms depend upon the retinal changes.

•Painless diminution of vision

•Dilated fundus examination shows typical

features.

Fundus FindingsFeatures of NPDR

● Microaneurysms

● Dot and blot hemorrhage

● Retinal edema and exudates

● Dilatation and beading of retinal veins

● Intra retinal Microvascular Abnormalities (IRMA)

Features of PDR

Neovascularization disc (NVD)

Neovascularization elsewhere(NVE)

In addition to other changes of NPDR

Early NPDR

Macular Edema

Proliferative Diabetic Retinopathy

Extra retinal fibrovascular proliferation extends beyond the internal limiting membrane (ILM).

• It’s the commonest cause of spontaneous vitreous hemorrhage in adults.

• About 2/3rd of Type I diabetics are likely to develop PDR over 3 decades.

Proliferative Diabetic Retinopathy

Proliferative Diabetic Retinopathy

Summary of Fundus Findings• Microaneurysms ,hemorrhage , hard

exudates

•Capillary non-perfusion , Intra Retinal

Microvascular Abnormalities (IRMA)

•Neovascularisation: NVD,NVE

•Vitreous hemorrhage , retinal detachment

Cause of Visual Impairment NPDR

● Macular edema (capillary leakage)

● Macular ischemia (capillary occlusion)

● Sequelae from ischemia related neovascularization

PDR

• Vitreous hemorrhage,

retinal detachment.

• Diabetic macular edema

• Ischemic macular changes

Diagnosis of Diabetic RetinopathyClinical Exam

•Direct ophthalmoscopy under mydriasis

•Slit lamp biomicroscopy using +90 D lens

•Fluorescein angiography

Screening Schedule•: Normal fundus , rare microaneurysms:

Annual review

•Mild NPDR: Every 9 months

•Moderate NPDR: Every 6 months

•Severe NPDR, CSME: Every 2-4 months

•PDR: Every 2-4 months

Treatment of Diabetic Macular Edema (DME)

Laser Photocoagulation• Grid laser :For diffuse retinal thickening outside FAZ.• Focal laser : microaneurysms in centre of hard

exudates.

Medical Treatment:

-intravitreal injection: Triamcinolome acetonide / anti-

VEGF

- posterior sub-tenon injection of corticosteroid

Surgery: Parsplana vitrectomy

Treatment of PDR

•Panretinal Laser photocoagulation (PRP) : For NVD And NVE

•Vitreoretinal surgery and PRP : - Severe persistent vitreous hemorrhage

- Dense, persistent premacular hemorrhage - Progressive proliferation despite laser

therapy - Retinal detachment involving macula

• Spot size (200-500 m)

• Follow-up 4 to 8 weeks

• Area covered by complete PRP• Initial treatment is 1200 + burns

Laser Panretinal Photocoagulation(PRP)

Prevention Visual Loss•Patient education and good diabetic control

•Control of hypertension, hyperlipidemia, renal

disease, anaemia, and avoidance of smoking

•Periodic dilated fundus examination

•Early treatment of macular edema and PDR

•Treatment of complications

Points to remember•Pathogenesis, types, clinical features and

diagnosis of diabetic retinopathy

•Cause of visual impairment in diabetic retinopathy

•Prevention of visual loss due to diabetic retinopathy

•Schedule of examination in diabetics

Frequently-Asked Questions

•Pathogenesis of diabetic retinopathy

•Fundus findings in diabetic retinopathy

• Diagnosis of diabetic retinopathy

•Patient education for prevention of

blindness from diabetes.