DIABETIC RETINOPATHY

Dr Paavan Kalra

Department of Ophthalmology,

S P Medical College,

Bikaner

• Diabetic retinopathy is a disorder of the retinal vessels that eventually develops to some degree in nearly all patients with long-standing diabetes mellitus.

• Contributes 4.8% of the 37 million cases of blindness throughout the world

• Most Common cause of bilateral severe visual loss in working age group in US

• A recent study in urban population in south India estimates prevalence of DM in adult population as high as 28% & the prevalence of DR in diabetics to 18%

RISK FACTORS

• Age at diagnosis of diabetes• Duration• Poor control of diabetes• Pregnancy• Hypertension• Nephropathy• Hyperlipidemia• Obesity• Anemia• Smoking• Cataract surgery

PATHOGENESIS Hyperglycemia

Intracellular sorbitol accumulation

Free radicals

Glycated end products

Disruption of ion channel function

Protein kinase C activation

Microangiopathy (damage to

capillary wall)

Direct effect on retinal cells

Hematological & Rheological changes

Edema Exudates

Microvascular OcclusionIschemia

IRMA Neovascularization

Fibrosis

Intra retinal hemorrhages

hemorrhageTraction

• Angiogenic stimulators

Vascular Endothelial Growth Factor – A

Platelet Derived Growth Factor

Hepatocyte Growth Factor

• Angiogenesis inhibtors

Endostatin

Angiostatin

Pigment Epithelium Derived Factor

CLASSIFICATION

Acc to Kanski 7th ed ( 2011)

Background Diabetic Retinopathy

Diabetic Maculopathy

Preproliferative Diabetic Retinopathy

Proliferative Diabetic Retinopathy

Advanced Diabetic Eye Disease

Most detailed classification was given by ETDRS study

PERICYTE LOSS

MICRO ANEURYSM THROMBOSED MICRO ANEURYSM

NORMAL CAPILLARIES

MICRO ANEURYSMS

INTRARETINAL

HEMORRHAGES

NORMAL EDEMA : CYSTOID

EXUDATES(HARD)

NORMAL ISCHEMIA

COTTON WOOL SPOTS

(“SOFT EXUDATES”)

INTRA RETINAL MICROVASCULAR ABNORMALITIES

Retinal arteriole obliterationVenous Segmentation

Venous BeadingVenous Loop

PROLIFERATIVE DR

NEO VASCULARIZATION

: DISC

NEO VASCULARIZATION

: ELSEWHERE

PROLIFERATIVE DR

ADVANCED DIABETIC EYE DISEASE

• Pre retinal hemorrhage

• Vitreous hemorrhage

• Traction RD• Rubeosis

Iridis• Neovascular

Glaucoma

DIABETIC MACULOPATHY

FOCAL

DIFFUSEISCHEMIC

DIFFUSE FOCAL

ISCHEMIC MACULOPATHY

HIGH RISK PDR

NVD > 1/4 - 1/3 disc area

NVD < 1/4-1/3 disc area with pre retinal or vitreous

hemorrhage

NVE >1/2 disc area

with pre retinal or vitreous hemorrhage

CONCEPTS FROM DRS & ETDRS

CLINICALLY SIGNIFICANT MACULAR EDEMA

CONCEPTS FROM DRS & ETDRS

Work Up - History

Duration of diabetes

Past glycemic control (hemoglobin A1c)

Medications

Systemic history (e.g., obesity, renal disease, systemic hypertension, serum lipid levels, pregnancy)

Ocular history

Workup : Examination

Visual acuity

Measurement of IOP

Gonioscopy when indicated (for neovascularization of the iris or increased IOP)

Slit-lamp biomicroscopy

Dilated funduscopy including stereoscopic examination of the posterior pole

Examination of the peripheral retina and vitreous, best performed with indirect ophthalmoscopy or with slit-lamp biomicroscopy, combined with a contact lens

Work up : Ophthalmic Investigations

• Fundus Photography• Fluorescein Angiography

to guide treatment of CSME

to identify Ischemic maculopathy

IRMA vs NV

evaluation in hazy media

not a screening modality

not a routine investigation• Optical Coherence Tomography

Retinal thickening

assessment & Monitoring of edema

vitreo macular traction•USG – B scan

INTERNATIONAL CLINICAL DIABETIC RETINOPATHY

DISEASE SEVERITY SCALE

INTERNATIONAL CLINICAL DIABETIC MACULAR EDEMADISEASE SEVERITY SCALE

Treatment Modalities

• LASER Photocoagulation (ARGON)

CSME – Focal & Grid

PDR with HRC – Pan Retinal Photocoagulation•Other LASERS for CSME – Frequency doubled Nd YAG

Micro pulse Diode•INTRA VITREAL anti VEGF – Bevacizumab, Ranibizumab•INTRA VITREAL steroids – Triamcinolone acetonide•PARS PLANA VITRECTOMY

Strict Glycemic Control delays the onset and progression

Deferral of focal photocoagulation

• hypertension or fluid retention associated with heart failure, renal failure,pregnancy, or any other causes that may aggravate macular edema.

• when the center of the macula is not involved, visual acuity is excellent, and the patient understands the risks

• Treatment of lesions close to the foveal avascular zone may result in damage to central vision and with time laser scars may expand and cause further vision deterioration.

• Adjunctive treatment may be considered- intravitreal corticosteroids or antivascular endothelial growth factor agents (off-label use).

Panretinal photocoagulation • may be considered as patients approach

high-risk PDR.• The benefit of early panretinal

photocoagulation at the severe nonproliferative or worse stage of retinopathy is greater in patients with type 2 diabetes than in those with type 1.

• Other factors, such as poor compliance with follow-up, impending cataract extraction or pregnancy, and status of fellow eye will help in determining the timing of the panretinal photocoagulation.

• It is preferable to perform the focal photocoagulation first, prior to panretinal photocoagulation to prevent laser-induced exacerbation of the macular edema.

• Screening of all cases above the age of 40 years irrespective of status of diabetes

THANK YOU