Phototherapeutic keratoectomy (PTK) after keratoconjunctivitis epidemica

Background: Persistent and recurrent nummuli after epidemic keratokonjunktivitis (EKC) often lead to reduced visual acuity and increased glare. In spite of long-term topical steroid therapy nummuli often recur. We tried to treat persistent nummuli with phototherapeutic keratectomy (PTK). Patients: PTK with an excimer laser (193 nm) was performed in 13 eyes of 9 patients with nummuli. The nummuli were observed over 3–72 months (mean: 36 months). Preoperatively, the visual acuity was 0.1–0.9 (mean: 0.39 ± 0.22) and the brightness acuity test (BAT) was 0.05–0.5 (mean: 0.25 ± 0.15). Prior to PTK all eyes had been treated with local steroids several times for recurrent nummuli. Results: During the follow-up from 15 to 56 months (mean: 33 ± 11.5 ms), 11 eyes had an increase in visual acuity: 0.3–1.0 (mean: 0.63 ± 0.26). The reduction of glare was especially beneficial for the patients: 0.3–0,9 (mean: 0.55 ± 0.21). One patient had a recurrence of nummuli in both eyes 6 weeks after PTK. The subjective-induced spheric refractive change was − 2.5 D to + 2.0 D. The astigmatic error changed between − 2.0 D to + 1.5 D. Conclusion: PTK seems to be an effective method of treating persistent, recurrent nummuli after EKC. The low rate of recurrence of nummuli after PTK is remarkable.