diabetic retinopathy

Question 1

define

Answer 1

Diabetic retinopathy results from microvascular injury due to poor glycaemic control.

Question 2

pathophysiology

Answer 2

There is
endothelial cell damage in the retinal vasculature, and associated basement membrane
thickening. This eventually leads to ischaemia in the retinal tissue, which signals vascular
endothelial growth factors to cause neo-angiogenesis. These new vessels however are weak,
friable and bleed easily. Without appropriate treatment, this pathogenic vicious cycle leads to
complications like vitreous haemorrhages, fibrosis and tractional retinal detachment.

Question 3

clinical findings

Answer 3

Clinical findings include a spectrum of ocular signs, mainly in the retina. There is an important
distinction to make between non-proliferative (NPDR) vs proliferative disease (PDR). The latter is
associated with new vessel formation (on the disc or elsewhere on the retina). Other signs can
include iris vessels termed rubeosis iridis that can cause secondary glaucoma.

Question 4

what is maculopathy?

Answer 4

If the changes occur close to the macula or involving the macula, it is termed diabetic
maculopathy. Patients with this experience central blurring of vision.

Question 5

mx

Answer 5

Treatment relies on:
1. Control of diabetes (measure HBA1c)
2. Control of modifiable risk factors like blood pressure, smoking cessation
3. Laser pan-retinal photocoagulation in severe NPDR and PDR to stop angiogenic drive by
laser burns in peripheral retina.
4. Anti-VEGF injections in diabetic maculopathy.
5. Vitrectomy and delamination vitreoretinal surgery is considered in fibrosis and tractional
retinal detachment cases

Question 6

proliferative vs non-proliferative

Answer 6

Non-proliferative diabetic retinopathy progresses to proliferative diabetic retinopathy, and
treatment initially must prioritise prevention and control of modifiable risk factors.