Effect of local irradiation with 630 and 860 nm low-level lasers on tympanic membrane perforation repair in guinea pigs

Abstract

In this study, we evaluated the effect of low-level lasers on the healing of tympanic membrane perforation, one of the most common otological pathologies. Twenty-four guinea pigs were randomly assigned to either the experimental or control group. One day after the induction of a 2 mm diameter, centred myringotomy in all animals, the tympanic membranes in the experimental group were irradiated with 630 and 860 nm lasers for 10 days. Two weeks later, histological changes in the membranes were evaluated. Tympanic membrane thickening and inflammatory cell infiltration in the tympanic membranes and surrounding tissues were significantly less in the experimental group (p < 0.001). The distance from the external auditory canal wall to the malleus tip did not differ significantly between the two groups (p = 0.42). The results show that the combined application of 630 and 860 nm lasers had a significant effect on the healing of tympanic membrane perforation, and on the prevention of thick fibrotic or atelectatic neomembrane formation.