F. Knoll, D. C. Ritterband, C. Y. Shih, I. J. Udell, J. A. Seedor The authors have no financial interest in the subject matter of this poster. A Comparative Study of Phototherapeutic Keratectomy with and without Photorefractive Keratectomy for the Treatment of Recurrent Erosion Syndrome

Phototherapeutic keratectomy (PTK) is a well- documented surgical option for patients with Recurrent Erosion Syndrome (RES). (1 – 6) Occasionally, PTK and photorefractive keratectomy (PRK) are performed together which allows for concurrent treatment of both recurrent erosions and refractive error. The purpose of this study was to compare outcomes of PTK combined with PRK, PTK alone, and PRK alone as surgical treatment modalities for recurrent erosion syndrome. Purpose

A retrospective chart review of all individuals at the New York Eye and Ear Infirmary who were treated for RES with either –PTK+PRK (Group A) –PTK alone (Group B) –PRK alone (Group C) Data collected included: history of previous corneal trauma, history of corneal epithelial basement membrane dystrophy (EBMD), previous medical treatment or surgical treatment, frequency of recurrent symptoms post-operatively, length of time to resolution of symptoms, and post-operative complications Data analysis was performed using Microsoft Excel. Data analysis was performed using Microsoft Excel. Methods

Table 1: Demographics Group A N= 10 (PTK + PRK) Group B N= 7 (PTK alone) Group C N= 13 (PRK alone) Age (years)45.2 ± ± ± 10.6 Gender (female)8 (80%)4 (57%)4 (31%) History of trauma4 (40%)1 (14.3%)5 (38.5%) Epithelial Basement Membrane Dystrophy (EMBD) 8 (80%)5 (71.4%)10 (76.9%) History of trauma & EBMD2 (20%)0 (0%)2 (15.4%) Granular Dystrophy0 (0%)1 (14.3%)0 (0%) History of lubrication (tears, Muro, or lacrilube)10 (100%)7 (100%)13 (100%) History of bandage contact lens use4 (36.4%)4 (57.1%)6 (46.2%) History of previous debridement6 (60%)2 (28.6%)0 (0%) History of previous anterior stromal puncture1 (10%)3 (42.9%)0 (0%)

Table 2: Results Group A (PTK + PRK) Group B (PTK alone) Group C (PRK alone) Number of Treatments (avg.)111 Percentage of recurrences2 (20%)2 (29%)4 (31%) Complete resolution of symptoms8 (80%)5 (71%)9 (69%) Time to complete resolution of symptoms (months) 1.2 ± ± ± 0.2 Complications (total)6 (60%)1 (14%)3 (23%) Dry eyes6 (60%)1 (14%)3 (23%) Corneal Haze2 (20%)0 (0%)

All patients reported a subjective decrease in symptoms (defined as diminished pain and/or a decrease in frequency of recurrent erosions postoperatively compared to preoperatively). The average time to complete resolution of symptoms was 1.2 ± 0.8 months for patients who had PTK + PRK, 1.3 ± 0.7 months for the PTK only group, and 0.9 ± 0.2 months for the PRK only group. These results were not statistically significant between groups. Results

Recurrence of erosion symptoms occurred postoperatively in –2/10 eyes (20%) of Group A –2/7 eyes (29%) of Group B –4/13 eyes (31%) of Group C Although Group A appeared to have a lower recurrence rate, these differences were not found to be statistically significant.* * Student’s t-test between Group A and Group B (p=0.36). Student’s t-test between Group A and Group C (p=0.29). Results

Individuals who suffer from both EBMD and a traumatic corneal abrasion have been shown to be at higher risk for developing recurrences status post treatment (7). In our study, 4 eyes fell into this category – 2 in group A and 2 in Group C. Three out of the 4 eyes experienced recurrences post treatment. Our study emphasizes the benefit of excimer laser as a safe and effective treatment modality for RES which is consistent with numerous previously published articles (1- 6). This study shows that there is no statistical difference between PTK+PRK, PTK alone, or PRK alone in their ability to obtain a resolution of erosion symptoms. Discussion

1. Baryla J, Pan Y, Hodge W: Long-Term Efficacy of Phototherapeutic Keratectomy on Recurrent Corneal Erosion Syndrome. Cornea. 2006; 25: Pogorelov P, Langenbucher A, Kruse F, Seitz B: Long-Term Results of Phototherapeutic Keratectomy for Corneal Map-Dot-Fingerprint Dystrophy (Cogan- Guerry). Cornea. 2006; 25: Cavanaugh T. Lind D, Cutarelli P, Mack R, Durrie D, Hassanein K, Graham C: Phototherapeutic Keratectomy for Recurrent Erosion Syndrome in Anterior Basemenet Membrane Dystrophy. Ophthalmology. 1999; 106: Morad Y, Haviv D, Zadok D, Krakowsky D, Hefetz L, Nemet P: Excimer laser phototherapeutic keratectomy for recurrent corneal erosion. J cataract Refract Surg. 1998; 24: Lohmann C, Sachs H, Marshall J, Gabel V: Excimer Laser Phototherapeutic Keratectomy for Recurrent Erosions: A Clinical Study. Ophthalmic Surg Lasers. 1996; 27: Ho C, Tan D, Chan W: Excimer Laser Phototherapeutic Keratectomy for Recurrent Corneal Erosions. Ann Acad Med Singapore. 1999; 28: Reidy J, Paulus M, Gona S: Recurrent Erosion of the Cornea: Epidemiology and Treatment. Cornea. 2000; 19(6): References