New article by Jan Tunér - Low level laser therapy of tinnitus - a case for the dentist?

Welcome to TLC - Tinnitus Laser Centre

TLC is a Swedish non-profit association with the aim of promoting the knowledge about Laser Therapy of tinnitus. Tinnitus is a very seriuos, debilitating and widespread phenomenon. Medicine has so far tried many therapies and they seem to have only one trait in common - they are not very successful. Laser therapy is not yet an established therapy for tinnitus, but taking the positive anecdotal reports into account, coupled with a number of positive clinical studies, we feel this is an area well worth of further exploration.

The cause of tinnitus is controversial, indicating that there is no absolute knowledge. In our experience there are three typical situations:
  1. The tinnitus is caused by a brain damage
  2. The tinnitus is caused by an acute or chronic acoustic trauma to the inner ear
  3. The tinnitus is caused by stress and consequent muscular spasm

For no 1 there is no therapy known to us
For no 2 irradiadiation directed towards the innear ear can be performed, in order to stimulate the "tired" cells in this region. Acute injuries respond well.
For no 3 relaxation therapy, physiotherapy, adjustment of the teeth (occlusion), bite splints and laser therapy to the involved muscles is recommended

TLC in itself does not treat patients, nor does it give advice to patients. On our web site there are links to clinics performing Tinnitus Laser Therapy, but these clinics are not TLC operations.
The literature
Low level laser therapy (LLLT) has been suggested as a possible therapy for tinnitus. Several studies have used Ginkgo biloba infusions in combination with LLLT, the former being a widespread but not well documented therapy for tinnitus. The number of studies are few and they will be briefly described in the following.

Witt [3] is one of the pioneers in this field, but to the knowledge of the author his results have not been published in any peer-review journal. Witt combines infusion of Gingko biloba (Egb 761, 17.5 mg dry extract per 5 ml amouple)) and laser. This may be a favourable combination but an evaluation of the contribution of the laser is not possible. More than 500 patients have been treated since 1989 and Witt claims that more than 60% of the patients have reached a considerable or total relief . The laser used is a combination of HeNe 12 mW/GaAs 5 x 10 mW. Treatment technique not stated.

Swoboda [4] did not find any significant effect of Gingo/laser. However, the ginkgo infusion used was at a homeopathic level (D3 = 1:1000 dilution), acc. to Witt.

Partheniadis-Stumpf [5] also failed to find any effect from the combined ginkgo (6 ml Tebonin) infusion and laser. However, the laser was applied at a distance of one cm above the mastoid. The non-contact mode reduces penetration considerably and the mastoid is not ideal for reaching the inner ear.

Plath [6] treated 40 tinnitus patients with 50 mg Ginkgo biloba. 20 patients received sham laser irradiation, 20 real laser. A HeNe 12 mW/GaAs 5 x 15 mW GaAs laser was used, irradiation procedure approximately the same as for Partheniadis-Stumpf. In this study, 50% of the patients reported a reduction of the tinnitus of more than 10 dB, compared with 5% in the control group, in both self-assessment and audiometric findings.

A similar study has been performed by von Wedel [7]. 155 patients were treated with Ginkgo infusion (5 ml Syxyl D3) and laser. The outcome was negative. No information about the type of laser, treatment technique or dosage is given, making an evaluation impossible.

Shiomi [8] has investigated the effect of infrared laser applied directly into the meatus acusticus, 21 J, once a week for 10 weeks. The result of this non-controlled study is as follows: 26% of the patients reported improved duration, 58% reduced loudness and 55% reported a general reduction in annoyance.

The same author [9] has also examined the effect of light on the cochlea, using guinea pigs. Direct laser irradiation was administred to the cochlea through the round window and the amplitude of CAP was reduced to 53-83% immediately after the onset of irradiation. The amplitude then returned to the original level. The results of this investigation suggest that LLLT might lessen tinnitus by suppressing the abnormal excitation of the 8th nerve or the organ of Corti.

More or less the same parameters were used in a controled study by Mirtz [10] but in this case there was no significant effect.

Wilden [11] [12] has applied a different method where the dose has been increased considerably. A set consisting of one HeNe laser and three powerful GaAlAs lasers is used, covering a large area over and around the ear, in the non-contact mode. Doses between 3.000 and 5.000 J are given each session. Laser is applied as a monotherapy. More than 800 patients have been treated with this concept and positive effects are reported, even for vertigo. Recent injuries in "the disco generation" are more easily treated than long-term chronic conditions. In a separate study [13] Wilden reports improvment of the hearing capacity of these patients, as evaluated by audiometry.

Beyer [14] has performed a very exact ex-vivo laser penetration study. Based on these findings it was possible to calculate the energy needed to obtain a dose of 4 J/cm2 in the cochlea itself. 30 patient were treated five times within 2 weeks. One group was irradiated with 635 nm diode laser, the other with 830 nm diode laser. By self-assessment around 40% of the patients reported a slight to significant attenuation of the tinnitus loudness of the irradiated ear. This study has been followed by a double blind study.

Prochazka [15] has evaluated the effect of combined Egb 761 Ginkgo infusion and laser in a double blind study. 37 patients were divided into three groups. One group had Egb 761 only, one Egb761 and placebo laser, one Egb761 and real laser, 830 nm. The results in the three groups were as follows: no effect 29/26/19, less than 50% relief 44/48/29, more than 50% relief 18/26/36, no more tinnitus 9/0/26. Irradiation was performed over the mastoid and over the meatus acusticus, twice a week, 8-10 sessions, total 175 J.

Rogowski [16] divided a group of 32 tinnitus patients into one group receiving LLLT and one receiving a placebo procedure. Dose, wavelength and treatment technique not stated in the available English abstract. The effect was evaluated through VAS. Within the patient group transiently evoked otoacoustic emissions (TEOAE) were measured before, during and after therapy. No significant difference between laser and placebo was found in annoyance or loudness of the tinnitus and in changes of TEOAE amplitude. These results indicate that there is no relationship between the effect of low-power laser and changes in cochlear micromechanics.

A few other indications in otorhinolaryngology have been treated with low level lasers, even with intravenous irradiation. [17-20]

It is obvious that the available literature on laser therapy of tinnitus is scarse and ambiguous. Some studies have used a combination of Ginkgo and laser, others laser as monotherapy. Differences in wavelengths, pulsing, dosage and treatment technique makes a firm evaluation impossible. However, the positive results reported in some studies do merit attention and further research. Recent clinical experience also suggests that the doses necessary for successful outcome of the therapy have to be increased considerably. Tinnitus is a grave condition, sometimes leading to suicide. It is also an increasing problem and the existing treatment modalities offered to tinnitus patients are not very effective. Young persons suffering from acoustic chocks (concerts, discos) can be more successfully treated with laser therapy. Understandably enough, a long standing condition in elderly persons is a severe condition taking 10-20 sessions to influence.

[3] Witt U, Felix C. Selektive photo-Biochemotherapie in der Kombination Laser und Ginkgo-Pflanzenextrakt nach der Methode Witt. Neue Möglichkeiten bei Innerohrstörungen. [Selective photo-biochemotherapy in the combination of laser and gingkoplan extracts acc. to the Witt method] (1989). Unpublished material.
[4] Swoboda R, Schott a. Behandlung neurotologischer Erkrankungen mit Gingko biloba Hevert, Hyperforat und Low-Power-Laser-Therapie. [Treatment of neurotologic diseases with Gingko biloba and low level laser therapy] Medizinische Akademie Erfurt. (1992)
[5] Partheniadis-Stumpf M, Maurer J, Mann W. Titel: Soft laser therapy in combination with tebonin i.v. in tinnitus. [in German)] Laryngorhinootologie 1993; 72(1):28-31
[6] Plath P, Olivier J. Results of combined low-power laser therapy and extracts of Ginkgo biloba in cases of sensorineural hearing loss and tinnitus. Adv Otorhinolaryngol.1995;49:101-4
[7] von Wedel H, Calero L, Walger M et al. Soft-laser/Ginkgo therapy in chronic tinnitus. A placebo-controlled study. Adv Otorhinolaryngol.1995;49:105-8
[8] Shiomi Y, Takahashi H, Honjo I, Kojima H, Naito Y, Fujiki N: Efficacy of transmeatal low power laser irradiation on tinnitus: a preliminary report. Auris Nasus Larynx 1997;24(1):39-42.
[9] Shiomi Y et al. [Effect of low power laser irradiation on inner ear] [in Japanese]. Pract Otol (Kyoto). 1994; 87: 1135-1140.
[10] Mirz F, Zachariae R, Andersen S E et al. The low-power laser in the treatment of tinnitus. Clin Otolaryngol 1999; 24: 346-354.
[11] Wilden L. The effect of low level laser light on innear ear diseases. In: Low Level Laser Therapy, Clinical Practice and Scientific Background. Jan Tunér and Lars Hode. Prima Books in Sweden AB (1999). ISBN 91-630-7616-0.
[12] Wilden L, Dindinger D. Treatment of chronic diseases of the inner ear with low level laser therapy (LLLT): pilot project. Laser Therapy. 1996; 8: 209-21210
[13] Wilden L, Ellerbrock D. Verbesserung der Hörkapazität durch Low-Level-Laser-Licht (LLLL). [Amelioration of the hearing capacity by low-level-laser-light (LLL)]. Lasermedizin. 1999; 14: 129-138.
[14] Beyer W et al. Light dosimetry and preliminary clinical results for low level laser therapy in cochlear dysfunction. Proc. Laser Florence '99.
[15] Prochazka M, Tejnska R. Comprehensive therapy of patients suffering from tinnitus. Proc. Laser Florence '99.
[16] Rogowski-M, Mnich-S, Gindzienska-E, Lazarczyk-B. [Low-power laser in the treatment of tinnitus - a placebo-controlled study] . Laser niskoenergetyczny w leczeniu szumow usznych-badania porownawcze z placebo. Otolaryngologia polska. [Otolaryngol-Pol]. 1999; 53 (3): 315-20
[17] Mishenkin N V et al. [Effects of helium-neon laser energy on the tissues of the middle ear in the presence of biological fluids and drug solutions]. [in Russian] Vest Otorinolaringol. 1990; 5: 18-21
[18] Bogomilskii M R et al. [Effect of low-energy laser irradiation on the functional state of the acoustic analyzer]. [in Russian] Vest Otorinolaryngol. 1989; 2: 29-34.
[19] Palchun V T et al. [Low-energy laser irradiation in the combined treatment of sensorineural hearing loss and Ménière's disease]. [in Russian] Vestnik Otorinolaryngol. 1996; 1: 23-25.
[20] Ribari O et al. [Closure of tympanic perforations with low-energy HeNe laser irradiation]. [in German] Acta Chir Academ Scient Hungariacae. 1980; 3: 229-238.

TLC research
Medical therapies of tinnitus have one thing in common: their effect is very limited (a survey in Swedish about various therapies is found under the link "Detta har provats"). With the positive anecdotal reports in mind and with the inspiration of the few positive studies, we feel that Laser Therapy for tinnitus is well worth investigating without prejudice. The following is a summary of TLC initiated research:

  1. Stockholm, private hospital. Finished. 15 consecutive tinnitus patients were given 200 mW 820 nm laser via a thin optical cord, very close to the ear drum and under visual control, total 24 J and 10-15 sessions. The idea was to check the studies [8] and [10] but with higher degree of dosage control. Through the small fiber the energy density was higher and the visual control close to the ear drum actually made the dosage inside the inner ear higher than in the other studies. The laser was a custom made Irradia Mid Laser, Stokholm. The outcome was negative, one reason probably the fact that no differential diagnosis of the patients were made.
  2. Stockholm, private hospital. The LEnergy 275co (Laser Evolution, Germany) is a stetoscope-like laser with red 780 nm laser light being directed into both ears simultaneously, 45 mW each. 20 patients will be treated. All patients have suspected aocustic trauma and no history of clenching or sore masticatory muscles. The idea is to pinpoint patients where the problem is likely to be centred in the inner ear, not in the muscles or in the spine. Patients will use the LEnergy 60 minutes daily, except Sundays, for one month. Study started in September 2000 and will take one year.
  3. Stockholm, Department of Odontology, Karolinska Institutet, Huddinge. Clincal examination of patients with tinnitus and temporo-mandibular-disorders. These patients have been treated rather successfully in this department through occlusal adjustment and in some cases bite splints. Laser Therapy has proved to improve and speed up the outcome of this therapy considerably. The laser used is a LASOTRONIC MED700, 820 nm, 300 mW. Ongoing for one year. Controlled study planned.
  4. Ystad, governmental dental clinic. Patients with Ménière´s disease have successfully been treated in this clinic, through TMD therapies. When the laser is used on an involved muscle, the tone of the tinnitus will change character in many cases. A "Tinnitus simulator" has been invented. The patient will adjust this "tinnitus generator" until it emits the same sound as the sound in the patient´s ear/ears. The laser will then be applied and the patient will again adjust the "TinSim" to the new sound. Theory: the TinSim will show: 1) the condition in the muscle affects the tinnutus sensation and 2) the laser affects the muscle. Start: February 2001. The laser used is a LASOTRONIC MED700, 820 nm, 300 mW.

Further research
TLC is interested in sharing its experiences with other researchers.