Transmeatal cochlear laser (TCL) treatment of cochlear dysfunction: a feasibility study for chronic tinnitus

Area of Science:

• Oto-rhino-laryngology
• Biomedical Engineering
• Photomedicine

Background:

• Low-level laser therapy (LLLT) is explored for inner ear conditions like tinnitus and sensorineural hearing loss.
• Previous LLLT studies show dose-dependent effects on nerve recovery, relevant to cochlear dysfunction.
• Current mastoidal and transmeatal irradiation for tinnitus lacks systematic dosimetric assessment.

Purpose of the Study:

• To present a novel laser application system for dose-controlled transmeatal cochlear laser-irradiation (TCL).
• To evaluate preliminary clinical outcomes of TCL in patients with chronic tinnitus and sensorineural hearing loss.

Main Methods:

• Developed a TCL system with four diode lasers (635 nm-830 nm) and a headset applicator based on dosimetric data.
• Conducted a preliminary study on 35 patients with chronic tinnitus/hearing loss unresponsive to standard treatments.
• Administered five single diode laser treatments with a specific irradiation dose (4 J/cm²) to the cochlear injury site.

Main Results:

• The TCL system was well-tolerated with no side effects or observable ear damage.
• Tinnitus loudness reduction was reported in 13 of 35 patients.
• Two patients reported complete absence of tinnitus after six months; hearing thresholds remained unchanged.

Conclusions:

• The developed TCL system is safe for treating chronic tinnitus.
• Preliminary results suggest TCL may attenuate tinnitus loudness, warranting further investigation.
• Large-scale, double-blind, placebo-controlled studies are necessary to confirm therapeutic effectiveness.