Transmeatal low-level laser therapy for chronic tinnitus with cochlear dysfunction.

Objectives: To establish the efficacy of low-level laser therapy for tinnitus.

Methods: We performed a prospective, randomized double-blind study on 60 outpatients with tinnitus presenting sensorineural hearing loss in the affected ear. They were randomly divided into two groups, the first performing active laser therapy 20 min a day for 3 months with a 650-nm, 5-mW soft laser (group L), the second using a dummy device which duplicated all aspects of active laser therapy except for the activation of the laser beam (group C). One subject in both groups dropped out due to an increase in tinnitus loudness. Two more patients in each group ceased to comply with the protocol due to familiar problems.

Results: The Tinnitus Handicap Inventory (THI) was considered the main outcome measure; no statistical difference was detected between the 2 groups in the THI total score (p = 0.97), and its functional (p = 0.89), emotional (p = 0.89) and catastrophic (p = 0.89) subscales. Moreover, a visual analog scale for self-perceived loudness of the tinnitus showed no difference between the groups (p = 0.69). Regarding psychoacoustic parameters, the minimum masking level showed no difference (p = 0.42), while loudness expressed in sensation level exhibited lower values in group L (p = 0.0127). Group L subjects also presented a decreased rate of hyperacusis (p = 0.02). No changes were detected in the audiometric threshold in both groups.

Conclusions: Soft laser therapy demonstrated no efficacy as a therapeutic measure for tinnitus.