Rose Bengal Photodynamic Antimicrobial Therapy as an Adjuvant Treatment for Infectious Keratitis

Abstract

Purpose : To report the clinical outcomes of Rose Bengal Photodynamic Antimicrobial Therapy (RB-PDAT) as an adjuvant treatment for severe infectious keratitis, and evaluate the success rate in avoiding the need for therapeutic keratoplasty.

Methods : We conducted a retrospective study. We reviewed the charts of all patients with severe infectious keratitis non-responsive to medical treatment who underwent RB-PDAT at Institute of Ophthalmology “Conde de Valenciana” between March 2023 and August 2023. Data collected included demographics, risk factors for infectious keratitis, microbiological diagnosis, Best Corrected Visual Acuity (BCVA) and clinical outcomes after RB-PDAT. RB-PDAT was performed by applying a solution of Rose Bengal (0.1%) to the 8 mm de-epithelized cornea for 30 minutes followed by irradiation with a 6mW/cm2 green LED source for a total energy exposure of 5.4J/cm2. All patients continued their standard medical treatment.

Results : The current study included 13 patients (10 females and 3 males) with a mean age of 52.53 ± 21.25 years old. The main risk factor for infectious keratitis was contact lens wear (30.76%), followed by ocular trauma (23.07%). The most common systemic comorbidity was diabetes mellitus (30.76%) and arterial hypertension (23.07%). Fusarium was the most frequent microorganism (46.15%), followed by Pseudomonas aeruginosa (15.38%) and Staphylococcus epidermidis (15.38%). Successful RB-PDAT defined by avoidance of therapeutic keratoplasty was achieved in 61.53% of the cases, with an average time of clinical resolution of 44.5 ±23.05 days after RB-PDAT.

Conclusions : RB-PDAT as an adjunct treatment for severe progressive non-responsive infectious keratitis may decrease the time for clinical resolution and reduce the need for a therapeutic penetrating keratoplasty.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.