- Characterized by growth of new vessels on the surface of the retina.
- Clinical features:
- Symptoms: progressive loss of vision, particularly in those
who are not properly followed or treated.
- Fine to severe loops of new vessels that may
grow on the optic disc: neovascularization
of the disc (NVD) or elsewhere (NVE)
- In the anterior segment, PDR is manifested by neovascularization
of the iris (NVI), the angle (NVA) and may eventually complicated
with neovascular glaucoma
- These new vessels may leak and resulting in retinal edema.
They are also fragile and prone to bleed
- Opaque fibrovascular proliferation tissue often appears
on the internal limiting membrane (adjacent to the new vessels)
and becomes adherent to the vitreous
- Contraction of this fibrovascular tissue may lead to:
- Distortion or dragging of the macula
- Mild to extensive retinal detachment
- Avulsion of retinal vessels and vitreous hemorrhages
- Risk factors:
- Duration of the diabetes
- 30-34 years of diabetes increase the risk of retinopathy
- Overt albuminuria
- High level of blood total cholesterol and LDL
- Others: race, cigarette smoking, alcohol
- Strict blood glucose, blood pressure and cholesterol control.
- Photocoagulation for clinically significant macular edema prior
to scatter (panretinal) photocoagulation (PRP).
- Consider PRP in severe proliferative diabetic retinopathy.
- Consider additional PRP if incomplete regression is observed,
increasing of the extent of vitreous hemorrhage or worsening of
overall vitreoretinal condition.
- Experimental treatments; Depo steroid injection for diabetic
macular edema, systemic protein kinase-C inhibitor and aldolase