Ophthalmologic emergencies in the patient with diabetes.

Diabetes is associated with many emergent ophthalmologic conditions. The management of patients with diabetes requires careful monitoring for visual symptoms and frequent physical examination for signs of retinopathy. Randomized studies have documented a significant reduction in the development of new retinopathy and the progression of existing retinopathy with tight control of diabetes. Photocoagulation laser therapy is helpful in preserving vision in severe nonproliferative retinopathy, for proliferative retinopathy, and for clinically significant macular edema. Vascular events include arterial and venous occlusions and cranial nerve palsies; important diagnostic clues are visual symptoms and the findings of ocular and neurologic examinations. Life-threatening infections associated with diabetes include endophthalmitis and mucormycosis, which require prompt diagnosis to prevent blindness or systemic infection. Herpes zoster infection, which is common in older patients and in patients with immunosuppression, may affect the trigeminal nerve and cause anterior uveitis and keratitis. Patients with zoster and skin vesicles on the face need emergent ophthalmologic evaluation and treatment because untreated ocular infection and inflammation may lead to scarring and synechiae formation in the anterior chamber, resulting in vision loss.