Rose Bengal Electromagnetic Activation With Green Light for Infection Reduction

Rose Bengal Electromagnetic Activation with Green light for Infection Reduction (REAGIR ) is an international, randomized, doubled masked, clinical trial. The purpose of this study is to determine differences in 6-month visual acuity between medical antimicrobial treatments alone versus antimicrobial treatment plus cross-linking with rose Bengal (RB-PDT). Patients presenting to one of the Aravind Eye Hospitals in India or to the Federal University of São Paulo ophthalmology clinic in Brazil with either smear or culture positive fungal or acanthamoeba keratitis or smear and culture negative corneal ulcers and moderate to severe vision loss, defined as Snellen visual acuity of 20/40 or worse, will be eligible for inclusion. Those who agree to participate will be randomized to one of two treatment groups: Group 4, Sham RB-PDT: topical chlorhexidine gluconate 0.02% (acanthamoeba), moxifloxacin 0.5% (smear/culture negative) or natamycin 5% (fungal keratitis) plus sham RB-PDT Group 5, RB-PDT: topical chlorhexidine gluconate 0.02% (acanthamoeba), moxifloxacin 0.5% (smear/culture negative) or natamycin 5% (fungal keratitis) plus RB-PDT.

Inclusion Criteria: * Presence of smear or culture positive fungal or acanthamoeba ulcer; smear or culture negative ulcer; or any atypical bacteria (such as Nocardia) * Moderate to severe vision loss, defined as Snellen visual acuity of 20/40 (6/12) or worse * Corneal thickness ≥350 µm, as measured on AS-OCT * Age over 18 years * Basic understanding of the study as determined by the physician * Commitment to return for follow up visits Exclusion Criteria: * Evidence of concomitant infection on exam, gram stain, or confocal microscopy (i.e. herpes, both bacteria and acanthamoeba on gram stain) * Impending or frank perforation at recruitment * Involvement of sclera at presentation * Non-infectious or autoimmune keratitis * History of corneal transplantation * History of intraocular surgery within last three months * Pinhole visual acuity worse than 20/200 in the unaffected eye * Participants who are decisionally and/or cognitively impaired * Presence of demestocele at recruitment