diabetic disease[1]

Diabetic eye disease

Dr Ho Sze Yuen

FHKAM (Ophthalmology)

Important facts

Risk of blindness is 25 times greater in diabetic than is non-diabetics

The incidence of DR is related more to the duration of diabetes than to any other factor.

In patients diagnosed as diabetic prior to the age to 30 years,

50% DR after 10 years

90% DR after 30 years

Background diabetic retinopathy

Pathogenesis

Microangiopathy affecting the arterioles, capillaries, venules

Microvascular occlusion and leakage.

Pathology of microvascular leakage breakdown of basement membrane of

capillaries

Consequences of microvascular leakage Increased vascular permeability Retinal heamorrhage and oedema

Circinate ring

Circinate ring laser

Pathology of microvascular occlsuion Ischeamia of retina Stimulate aniogenic factor Proliferation of new vessels Bleed from new vessels

Consequences of microvascular occlusion Microvascular occlusion hyopoxic retina vasoformative substnace Neovascularization

Proliferative diabetic retinopathy

Preliferatibe diabetic retinopathy

Proliferative diabetic retinopathy

Proliferative diabetic retinopathy

Pre-retinal haemorrhage

Recommendation

Annual check of retina, either by GP or ophthalmologist

When to refer

When you see pathology, not to wait until vision drops

Vision is normal in background diabetic retinopathy, until macular edema

Vision is normal in proliferative diabetic retinopathy, with new vessels until vitreous haemorrhage

Fluorescein angiography procedure

Fluorescein angiogram

Fluorescein angiogram

Pan-retinal phtocoagulation(PRP)

Laser application

Proliferative diabetic retinopathy after PRP

Tractional retinal detachment

Advanced tractional retinal detachment

Indications for laser

Macular edema Proliferative diabetic retinopathy

Circinate ring

Circinate ring laser

Effects of macular laser seal off the leaking vessels, Prevent further leakage, The existing edema needs 2-3 months to be

absorbed Since scars are induced by laser, the vision may

drop a little bit after laser, The result may sacrifice some vision, to attain a

stable vision in future

Effects of laser for new vessels,pan-retinal photocoagulation (PRP) To ablate the peripheral normal retina, and

save the central part Aim is to decrease the nutrient demand, the

residual nutrient can concentrate to the central retina

Patient may feel dim or blur of peripheral field

Pan-retinal phtocoagulation(PRP)

Conclusion

Diabetic retinopathy is more likely in patients with long history of DM, or poor control

Diabetic retinopathy is generally a downhill disease

Laser is the only treatment to decrease the rate of deterioration or stabilize the condition

Conclusion

If vitreous heamorrhage occurs, laser cannot penetrate the haemorrhage and aim on the retinal pathology, the surgery is indicated to aspirate the haemorrhage

To prevent complication is better than to treat

To treat early is better than to treat late