M. Cristina Leske

Trends in Cataract Surgery and Intraocular Lenses in the United States

Cataracts are the second leading cause of blindness in the United States. The rate of cataract surgery has greatly increased in the past several years, in part because of the extensive use of intraocular lenses for aphakic correction. It is estimated that more than 600,000 cataract operations were done in 1982. During a similar period, an estimated 496,000 intraocular lenses were implanted. Thus, more than 70% of all cataract operations in the United States involved intraocular lens implantation. Although iris fixation lenses accounted for 52% of all intraocular lenses implanted in 1978, during the six-month period from July 1982 through January 1983 57% of all implanted intraocular lenses were posterior chamber lenses and 40% were anterior chamber lenses.

Incidence of diabetic retinopathy in the Barbados Eye Studies

PURPOSE To examine the 4-year incidence and risk factors for diabetic retinopathy (DR) among black participants with diabetes in the Barbados Eye Studies (BES). DESIGN Population-based incidence study. SETTING AND PARTICIPANTS Four hundred ten persons with diabetes mellitus (DM) from the BES cohort, which was based on a simple random sample of Barbadians, 40 to 84 years of age at baseline. MAIN OUTCOME MEASURES Development of DR, assessed by independent gradings of 30 degrees color stereo fundus photographs of the disc and macula. Associations were evaluated by logistic regression analyses. RESULTS After 4 years, DR developed in 92 of 306 (30.1%; 95% confidence interval, 25.0%, 35.5%) persons unaffected at baseline. The incidence of DR was 31.9% in those with known DM at baseline and 20.9% in newly diagnosed DM. Clinically significant macular edema developed in 16 (4.5%) of 353 individuals at risk. Seven (6.9%) of the 101 persons with minimum or moderate DR at baseline progressed to proliferative DR. Age-specific incidence declined from 36.2% at age 40 to 49 years to 28.8% and 24.2% over the subsequent two decades, increasing to 38.2% among those >/=70 years. Risk factors for DR were increased systolic blood pressure (relative risk [RR], 1.16 [1.03, 1.31]/10 mmHg increase); use of oral hypoglycemics (RR, 2.4 [1.3, 4.2]); and use of insulin (RR, 6.1 [1.7, 22.1]) (vs. no treatment or diet only); and elevated glycated hemoglobin (GHb; RR, 6.4 [2.5, 16.0]); GHb >11.5% vs. GHb </=8%). CONCLUSIONS High rates of incident DR were evident in the black BES population, also known to have high rates of DM. Prevention of visual loss caused by DR in this population has high priority, including optimal glycemic and blood pressure control.

Epidemiology of Ocular Melanoma

Ocular melanomas are eye tumors composed of melanocytic cells with malignant characteristics. Most ocular melanomas arise from uveal melanocytes distributed throughout the stroma of the choroid, ciliary body, and iris; conjuctival melanocytes may also be the cells of origin for melanomas [1]. Since conjunctival and uveal melanocytes share a common embryologic origin with melanocytes of the skin from the neural crest [2], investigators have suggested the possibility of similar etiologies for ocular and cutaneous melanoma [3, 4]. While both melanomas share certain clinical and epidemiologic characteristics, other factors demonstrate no correlation. This issue needs further investigation, as discussed in this review.