Diabetes Mellitus
- Systemic disorder marked by elevated blood sugar
- Type 1 (onset in youth) autoimmune insulin deficiency
- Type 2 (onset in adulthood) insulin resistance
- Major cause of visual impairment, because...
- Retinal blood vessels leak to cause macular edema, and...
- Retinal blood vessels occlude to cause retinal ischemia, neovascular and fibrovascular proliferation, vitreous hemorrhage, retinal detachment
- Vision-reducing diabetic macular edema present in 10% within 15 years of diagnosis
- Nonproliferative retinopathy present in 25% within 15 years of diagnosis
- Other yellow-white things in retina
- Hemorrhages of systemic hypertension, blood dyscrasias, radiation, connective tissue disorders, conditions that cause microvascular incompetence
- Microaneurysms unique to diabetes mellitus, but difficult to see without special instruments
- Neovascularization distinguished from normal vascularization by their weblike density
- Fibrovascular proliferation after eye trauma, retinal detachment
- Refer patient with new visual loss with urgency depending on acuteness of visual symptoms
- Refer patients without visual symptoms to ophthalmologist non-urgently at time of diagnosis
- Critical preventive measures: tight control of blood sugar, blood pressure, lipids
- Grid laser photocoagulation treats macular edema
- Intravitreal injection of corticosteroids or anti-vascular endothelial growth factors (anti-VEGF) treats neovascular retinopathy
- Pan-retinal photocoagulation also treats neovascular retinopathy, often causing impressive regression of new vessels
- Vitrectomy treats advanced fibrovascular proliferative retinopathy
- Masked trials found that these treatments stabilize and sometimes reverse vision loss if applied early