Use of low-level laser therapy for patients with chronic rhinosinusitis: a single-blind, sham-controlled clinical trial

Chronic rhinosinusitis (CRS) is one of the most common conditions all over the world. The purpose of this study was to investigate the effects of low-level laser therapy (LLLT) in patients with CRS. Fourteen adult patients with CRS participated in this single-blind, sham-controlled clinical trial (12 male, mean age 40 years). Patients received five successive sessions of sham laser followed by five successive sessions of real laser after 2 days. Ga-Al-As laser of 830 nm in a continuous mode at a power output of 30 mW and energy dose of 1 J was applied on the cheeks and the forehead for the maxillary and frontal sinuses, respectively. Laser was delivered on six points over each sinus, each point for 33 s. Four measurements were taken. The total symptom score (TSS) was calculated as the primary outcome measure. The effects of LLLT on TSS were evaluated by using repeated measure ANOVA. The percentage improvement of real laser and sham laser was compared by Wilcoxon signed ranked test. Cohen's d was used to calculate the effect size. Total symptom score significantly improved after real laser (p = 0.015, Cohen's d = 0.69). The percentage improvement for real laser (34.12 ± 46.43) was significantly better than the sham laser (5.02 ± 37.34, Z =  - 2.23, p = 0.026). No significant improvements were observed after sham laser. This study indicates that five-session active LLLT when compared with sham is effective in the treatment of CRS symptoms.