Efficacy of Dual-Wavelength Light-Emitting Diode Phototherapy for Chronic External Otitis: A Randomized Controlled Pilot Study

Chronic external otitis (CEO) is a persistent inflammatory condition of the external auditory canal characterized by pruritus, otalgia, and otorrhea and is often difficult to treat. This study evaluated the clinical efficacy and safety of a novel portable dual-wavelength light-emitting diode (LED) phototherapy device at wavelengths of 660 and 940 nm.

This prospective, randomized, controlled pilot study was conducted at a tertiary hospital between August and November 2024. Twenty-one adults with CEO persisting for more than 1 month were randomly assigned to three groups (n=7 per group). Randomization was performed using a computer-generated block randomization sequence. Group 1 received LED phototherapy alone, Group 2 received topical ofloxacin alone, and Group 3 received combined LED phototherapy and antibiotic therapy for 2 weeks. Outcomes were evaluated at baseline and after treatment using otoscopic findings, pure-tone audiometry, and visual analog scale scores for pain and discomfort.

All 21 participants completed the study. Otoscopic examination showed that Group 2 showed the highest resolution of otorrhea, with 75.0% complete resolution compared with 25.0% in Group 1 and 20.0% in Group 3 (p=0.194). No significant between-group differences were observed in erythema and edema. Regarding subjective symptoms, LED therapy (Groups 1 and 3) resulted in a marked improvement. Group 1 showed a significant reduction in discomfort from 7.00 to 3.00 (p<0.05), whereas Group 3 also showed a significant reduction from 6.43 to 2.14 (p<0.01). Group 2 had a substantially lower baseline pain score (0.60±1.34), thereby limiting meaningful comparison due to a floor effect. Pure-tone audiometry revealed no significant changes across treatment groups. No serious adverse events, photosensitivity reactions, or thermal injuries were observed.

This pilot study revealed that dual-wavelength LED phototherapy is safe and significantly reduces pain and discomfort in CEO, whereas topical antibiotics remain superior for otorrhea resolution. Collectively, LED phototherapy may serve as an adjunctive or alternative option, particularly for patients seeking non-antimicrobial treatment.