Rose Bengal Photodynamic Antimicrobial Therapy (RB-PDAT) for Fungal Keratitis:
A Pilot Case Series
Neel D. Pasricha1,2, Sankalp S. Sharma3, Tom Lietman2, Jennifer Rose-Nussbaumer2,4, Jean Marie Parel5,6, Guillermo Amescua5,6, N. Venkatesh Prajna3
1Department of Ophthalmology, University of California San Francisco, San Francisco, California, USA; 2Francis I. Proctor Foundation, University of California San Francisco, San Francisco, California, USA; 3Department of Cornea, Aravind Eye Care System, Madurai, India; 4Byers Eye Institute, Stanford University, Palo Alto, California, USA; 5Anne Bates Leach Eye Center, University of Miami Miller School of Medicine, Miami, Florida, USA; 6Ophthalmic Biophysics Center, University of Miami Miller School of Medicine, Miami, Florida, USA
Purpose: To report the safety and efficacy outcomes of Rose Bengal Photodynamic Antimicrobial Therapy (RB-PDAT) in a case series of four patients with confirmed fungal keratitis at an eye hospital in South India.
Methods: Four eyes of four patients presenting with smear-positive fungal keratitis received gold standard topical natamycin 5% at presentation plus RB-PDAT within 48 hours. RB-PDAT consisted of a 30-minute loading dose of topical Rose Bengal (0.2% RB in BSS) applied at 5-minute intervals to the de-epithelialized cornea followed by irradiation with a 6 mW/cm2 custom-made green LED source for 15 minutes (5.4 J/cm2). Repeat corneal cultures were obtained 30 minutes after the procedure.
Results: At presentation, two of the four eyes were culture-positive for Fusarium species, however, repeat corneal cultures 30 minutes after RB-PDAT was positive in only one of the two eyes. By postoperative week 1, BCVA improved from LogMAR 0.75+0.10 (Snellen equivalent 20/112) to 0.63+0.24 (Snellen equivalent 20/85; p=0.48) and infiltrate size reduced from 9.5+3.7 to 7.3+4.3 mm2 (p=0.33). There were no complications associated with the RB-PDAT procedure.
Conclusions: RB-PDAT is a promising novel therapy for fungal keratitis.*
*Postoperative week 3 data will be available by the 2022 OMIG Meeting.
Support: Supported by grants UG1EY028518 and EY031372 from the National Institutes of Health/National Eye Institute, Research to Prevent Blindness Career Development Award (Pasricha), and All May See Foundation grant. This work was made possible in part by the Research to Prevent Blindness Unrestricted Grant to the University of California San Francisco, Department of Ophthalmology.
Disclosure: N: (Pasricha, Sharma, Lietman, Rose-Nussbaumer, Prajna);
P: University of Miami (Marie-Parel, Amescua)