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OLECULAR MEDICINE OFFERS PROMISE FOR THE preventionofvisionlosscausedbyocularneovascularization in diabetic retinopathy and exudative age-related macular degeneration (ARMD). During the past decade, significant advances have been made in angiogenesis research, such that the understanding about new vessel formation in disease has increased considerably. This knowledge has led to the development of numerous inhibitors of angiogenesis. Among a host of novel therapeutics for ocular neovascularization, 2 inhibitorsoftheangiogenicagentvascularendothelialgrowth factor (VEGF)—pegaptanib sodium and ranibizumab— are poised for imminent clinical application. However, the need for repeated intraocular injection of these agents and thepotentialforlocalandsystemicadverseeffectsmaypose hurdles for these emerging therapies. Conventional Treatments Have Limitations

• One hundred thirty-two penetrating keratoplasties (91 patients) for herpetic keratoplasty were reviewed retrospectively. The overall survival rate of clear keratoplasties to two years was 64% and to five years was 62%. The significant prognostic factors were preoperative ocular inflammatory status and degree of corneal vascularization. The two-year survival rate of a clear keratoplasty was 69% where eyes were inflamed at the time of surgery, compared with 44% in actively inflamed eyes. Allograft rejection, the major cause of a clouded herpetic keratoplasty, increased in frequency with increasing corneal vascularization. Antiviral cover was not used with routine postoperative steroids or with steroid intensive therapy for rejection. Epithelial herpetic recurrences occurred in 32% of eyes undergoing allograft rejection within four months of initiation of treatment for rejection. This is compared with otherwise uncomplicated keratoplasties where the epithelial recurrence rate was 6% at four months, on high-dose postoperative corticosteroid therapy without antiviral cover.

• A model of bacterial keratitis in rats was developed to quantify the effect of antibiotics and corticosteroid on the infective process. Corneas were inoculated with Staphylococcus aureus, Pseudomonas aeruginosa , or Streptococcus pneumoniae . The natural history of infection with these organisms was determined. Groups of animals received topical antibiotics and prednisolone acetate. The effect of treatment on the number of leukocytes and viable bacteria in the corneas was determined. Prednisolone did not influence the effect of the antibiotics; however, steroid treatment alone increased the pseudomonad count as much as 20-fold above the count in untreated eyes. In general, both the antibiotic and steroid treatments were more successful when begun eight hours after infection than when begun at 24 hours. A 1% gentamicin sulfate preparation proved effective against each of the infections, including a pneumococcal strain considered resistant on the basis of in vitro tests.

• Clinical features of 152 patients with herpetic keratitis after a five-year observation period were analyzed. When compared with dendritic ulceration, geographic ulcers that had been symptomatically present for a longer time were more likely to have been treated with a topical steroid and took longer to heal. After treatment of the corneal ulceration, 40% of the patients experienced a recurrent herpetic ulcer, 25% experienced disciform or irregular stromal keratouveitis, 5% experienced ocular hypertension, and 6% had a decrease in visual acuity caused by corneal scarring. Recurrent ulcerative herpetic keratitis occurred more frequently in men and in patients who entered the study with a history of previous herpetic ulceration.