The purpose of this study was to evaluate the low-power laser on the treatm
ent of tinnitus. In a randomized, prospective, double-blind, placebo-contro
lled trial, either active or placebo low-power laser irradiation was given
through the external acoustic meatus of the affected ear towards the cochle
a. The active laser applied 50mW (cw, 830 nm) over a period of 10 min per s
ession. Forty-nine patients with severe, chronic uni- or bilateral tinnitus
were studied. The main outcome was measured using psychoacoustical match o
f tinnitus loudness and pitch, Visual Analogue Scale (VAS) ratings of subje
ctive loudness, annoyance and attention involved, scores on the Tinnitus Ha
ndicap Inventory (THI), the Tinnitus Coping Style Questionnaire (TCSQ), and
a number of psychosocial questionnaires. The results showed only moderate
(18%) subjective improvement with no statistically significant differences
between the effects of the active laser and placebo treatments. Also, there
were no statistically significant differences in prepost measurements of t
innitus loudness, VAS scores, THI scores, or TCSQ scores for patients treat
ed with active laser compared with those treated with placebo. We conclude
that low-power laser treatment is not indicated in the treatment of tinnitu
s. Reports of significant benefits of this treatment in previous, mostly un
controlled or single-blinded studies may be explained by the placebo effect
.