Rose Bengal Photodynamic Antimicrobial Therapy: A Review of the Intermediate-Term Clinical and Surgical Outcomes

center dot PURPOSE: To evaluate the intermediate-term clinical outcomes of Rose Bengal Photodynamic Antimicrobial Therapy (RB-PDAT) for infectious keratitis; secondar-ily, to evaluate the surgical outcomes of individuals who underwent optical keratoplasty after RB-PDAT.center dot DESIGN: Retrospective cohort study.center dot METHOD: A retrospective chart review was performed of 31 eyes from 30 consecutive individuals with infec-tious keratitis refractory to standard medical therapy who underwent RB-PDAT at the Bascom Palmer Eye Insti-tute between January 2016 and July 2020. Data collected included demographics, risk factors for infectious kerati-tis, microbiological diagnosis, best spectacle-corrected vi-sual acuity (BCVA), clinical outcomes after RB-PDAT, and complication rates post-keratoplasty. RB-PDAT was performed as described in previous studies. Graft sur-vival was evaluated using Kaplan-Meier curves with log-ranks in individuals who underwent keratoplasty after RB-PDAT.center dot RESULTS: The mean age of the study population was 53 +/- 18.0 years. In all, 70% were female; 53.3% self-identified as non-Hispanic White and 43.3% as His-panic. Mean follow-up time was 28.0 +/- 14.4 months. Risk factors included contact lens use (80.6%), history of infectious keratitis (19.3%), and ocular surface dis-ease (16.1%). Cultures were positive for Acanthamoeba (51.6%), Fusarium (12.9%), and Pseudomonas (6.5%). Of the individuals with Acanthamoeba infection, 22.5% were treated with concomitant Miltefosine. Clinical reso-lution was achieved in 77.4% of patients on average 2.72 +/- 1.85 months after RB-PDAT, with 22.5% requiring therapeutic penetrating keratoplasties and 54.8% subse-quently requiring optical penetrating keratoplasties. At 2 years, the overall probability of graft survival was 78.7%, and the graft failure rate was 21.3%.center dot CONCLUSION: RB-PDAT is a potential adjunct ther-apy for infectious keratitis that may reduce the need for a therapeutic penetrating keratoplasty. Patients who un-dergo keratoplasty after RB-PDAT may have a higher probability of graft survival at 1 year postoperatively. (Am J Ophthalmol 2022;243: 125-134.(c) 2022 Else -vier Inc. All rights reserved.)