Early- versus late-onset infectious keratitis after radial and astigmatic keratotomy: Clinical spectrum in a referral practice

Purpose: To compare the clinical characteristics of early - versus late-ons et keratitis after radial keratotomy (RK) and astigmatic keratotomy (AK). Setting: Referral subspecialty practice. Methods: This retrospective review comprised 19 patients with infectious ke ratitis after RK and AK. Early- versus late-onset groups were analyzed for predisposing conditions; infiltrate location, size, and depth; microbiologi c data; and finale visual outcome. Results: Ten patients in the early-onset group developed keratitis within a mean of 7.4 days after surgery (range 3 to 14 days). Nine patients in the late-onset group developed keratitis a mean of 5.4 years after surgery (ran ge 1.5 to 15.0 years). Staphylococcus aureus was the predominant organism i n the early-onset group and Pseudomonas aeruginosa in the late-onset group. In the early-onset group, most infiltrates occurred in the paracentral asp ect of the RK incision and extended to the middle or posterior stroma. In t he late-onset group, most infiltrates occurred in the peripheral portion of the RK incision and were localized to the superficial stroma. A hypopyon w as present in 7 of 10 ulcers in the early group and in 1 of 9 in the late g roup. Two patients in the early group developed endophthalmitis. Most patie nts in the late-onset group had incisional pseudocysts; 2 had other risk fa ctors for keratitis. Final visual acuity ws 20/40 or better in 7 of 10 pati ents in the early group and in 8 of 9 patients in the late group. Conclusions: Early-onset corneal ulcers after incisional refractive keratot omy were usually paracentral and deep, whereas late-onset ulcers were usual ly peripheral and superficial. Despite th predominance of Staphylococcus an d Pseudomonas in the early- and late-onset groups, respectively, a variety of organisms may be responsible for infections in keratotomy incisions. J C ataract Refract Surg 1999; 25:1615-1619 (C) 1999 ASCRS and ESCRS.