Effect of low-level laser treatment on cochlea hair-cell recovery after acute acoustic trauma.
Dankook University, Medical Laser Research Center, Cheonan, Republic of Korea.
We investigated the effect of low-level laser radiation on rescuing hair cells of the cochlea after acute acoustic trauma and hearing loss. Nine rats were exposed to noise. Starting the following day, the left ears (NL ears) of the rats were irradiated at an energy output of 100 to 165 mW/cm(2) for 60 min for 12 days in a row. The right ears (N ears) were considered as the control group. Frequency-specific hearing levels were measured before the noise exposure and also after the 1st, 3rd to 5th, 8th to 10th and 12th irradiations. After the 12th treatment, hair cells were observed using a scanning electron microscope. Compared to initial hearing levels at all frequencies, thresholds increased markedly after noise exposure. After the 12th irradiation, hearing threshold was significantly lower for the NL ears compared to the N ears. When observed using an electron microscope, the number of hair cells in the middle turn of the NL ears was significantly larger than that of the N ears. Our findings suggest that low-level laser irradiation promotes recovery of hearing thresholds after acute acoustic trauma.
Moderate and severe sudden deafness treated with low-energy laser irradiation combined with auricular acupoint sticking.
Department of Rehabilitation Medicine, The First Affiliated Hospital of Xinxiang Medical College, Weihui 453100, Henan Province, China. email@example.com
To test the therapeutic effect on moderate and severe sudden deafness treated with low-energy laser irradiation on acupoint and external auditory canal combined with auricular point sticking (APS) and as compared with electroacupuncture.
Two hundred and fifty-eight cases of moderate and severe sudden hearing loss were randomly divided into an observation group 1, an observation group 2 and a control group, 86 cases in each group. In three groups, 10% low molecular Dextran 500 mL were used for intravenous infusion. Based on the above treatment, the observation group 1 was treated with low-energy laser irradiation on acupoint and external auditory canal (such as Ermen (TE 21), Tinggong (SI 19) and Tinghui (GB 2)), combined with APS at Gan (liver), Shen (kidney) and Neifenmi (endorine), etc. The observation group 2 was treated with electroacupuncture at the same acupoints as those point irradiation in observation group 1. Fifteen days made one session. The therapeutic effects were evaluated after one and two sessions.
After two sessions, The cured rate was 40.7% (35/86) in observation group 1 and 38.4% (33/86) in observation group 2,which were superior to 25.6% (22/86) in control group (both P < 0.05). Compared with one session, the therapeutic effects after two sessions were better in two observation groups (both P < 0.05), but there was no significant difference between two groups (both P > 0.05). In comparison of the improvements of frequency audiometry and auditory function, the two observation groups were better than those in control group (P < 0.05, P < 0.01), and the improvements after two sessions were better in two observation groups (both P < 0.01).
Both of low-energy laser irradiation on acupoint and external auditory canal combined with APS and electroacupuncture are able to decrease frequency audiometry, improve auditory function, and the therapeutic effects are better with prolongation of treatment time. The clinical efficacy of above two the rapies on moderate and severe sudden deafness is superior remarkably to that of conventional treatment. The therapy of low-energy laser irradiation on acupoint and external auditory canal combined with APS can replace the electroacupuncture therapy in treating moderate and severe sudden deafness.
Lasers Med Sci. 2011 Dec 4. [Epub ahead of print]
Effect of low-level laser therapy on cochlear hair cell recovery after gentamicin-induced ototoxicity.
Department of Otolaryngology-Head & Neck Surgery, Dankook University College of Medicine, Cheonan, Korea.
Cochlear hair cells are the sensory receptors of the auditory system. It is well established that antibiotic drugs such as gentamicin can damage hair cells and cause hearing loss. Rescuing hair cells after ototoxic injury is an important issue in hearing recovery. Although many studies have indicated a positive effect of low-level laser therapy (LLLT) on neural cell survival, there has been no study on the effects of LLLT on cochlear hair cells. Therefore, the aim of this study was to elucidate the effects of LLLT on hair cell survival following gentamicin exposure in organotypic cultures of the cochlea of rats. The cochlea cultures were then divided into a control group (n=8), a laser-only group (n=8), a gentamicin-only group (n=8) and a gentamicin plus laser group (n=7). The control cultures were allowed to grow continuously for 11 days. The laser-only cultures were irradiated with a laser with a wavelength of 810 nm at 8 mW/cm(2) for 60 min per day (0.48 J/cm(2)) for 6 days. The gentamicin groups were exposed to 1 mM gentamicin for 48 h and allowed to recover (gentamicin-only group) or allowed to recover with daily irradiation (gentamicin plus laser group). The hair cells in all groups were stained with FM1-43 and counted every 3 days. The number of hair cells was significantly larger in the gentamicin plus laser group than in the gentamicin-only group. The number of hair cells was larger in the laser-only group than in the control group, but the difference did not reach statistical significance. These results suggest that LLLT may promote hair cell survival following gentamicin damage in the cochlea. This is the first study in the literature that has demonstrated the beneficial effect of LLLT on the recovery of cochlear hair cells.
Vestn Otorinolaringol. 2011;(2):43-5.
[Intravenous laser irradiation of blood for the combined treatment of patients presenting with chronic sensorineural hearing loss].
A method for the treatment of chronic sensorineural hearing loss (CSNHL) is proposed that includes administration of trental followed by intravenous laser irradiation of blood (IVLBI). The study included 81 patients at the age from 20 to more than 60 years presenting with CSNHL. They were allocated to three groups; the patients in group 1 (n=32) were given trental intravenously followed by intravenous laser irradiation of blood, those of group 2 (n=24) were treated with IVLBI alone while patients of group 3 (n=25) received “traditional” treatment. Audiometric examination and rheoencephalography were carried out before and after therapy. The hearing improved to 18-20 dB in group 1, to 10-15 dB in group 2, and to 10 dB in group 3. The improvement of rheoencephalographic characteristics was documented in the patients of all groups but was especially pronounced in group 1. It is concluded that the proposed method significantly increases the efficiency of treatment of chronic sensorineural hearing loss.
Vestn Otorinolaringol. 2011;(1):39-40.
The application of supravascular laser irradiation of blood for the treatment of cochleovestibular disorders.
A total of 165 patients presenting with neurosensory impairement of hearing and Meniere’s disease were treated by supravascular (extracorporeal) laser irradiation of blood. The study undertaken to evaluate the efficacy of this treatment confirmed its beneficial effect in patients with acute hearing disorders. It was equally effective as regards elimination of labyrinthine hydropsis in patients presenting with Meniere’s disease. The method proved less efficacious for the management of long-standing hearing impairement and chronic loss of hearing, but it can be used to prevent the development of these conditions.
J Res Med Sci. 2011 Jan;16(1):33-8.
Low-level laser for treatment of tinnitus: a self-controlled clinical trial.
Okhovat A, Berjis N, Okhovat H, Malekpour A, Abtahi H.
Department of Otorhinolaryngology, School of Medicine, Isfahan University of Medical Science, Isfahan, Iran.
BACKGROUND: Despite the high prevalence and morbidity, tinnitus still remains an obscure symptom. We assessed the efficacy of low-level laser for treatment of tinnitus.
METHODS: It was a self controlled clinical trial study on 61 outpatients with subjective tinnitus. The patients were irradiated with a 650-nm, 5-mW soft laser for twenty days and twenty minutes per day. The sensation of tinnitus was measured on a Visual Analog Scale (VAS) before and two weeks after treatment and they were compared by means of Wilcoxon signed ranktest.
RESULTS: Thirty-eight (62.3%) patients were men and twenty-three (37.7%) were women. Fourteen patients (31.8%) worked in noisy environment. The VAS mean difference before and after the treatment was statistically significant (p < 0.0001). The best treatment effect was in the youngest group and there were significant differences between this group and the middle age and older groups (p = 0.018 and 0.001, respectively). The mean VAS score reduction was not statistically significant between male and female patients (p = 0.23). Also, the treatment outcome according to the noise level in patient’s workplaces was not significantly different in women (p = 0.693), but it was significant in men (p = 0.029).
CONCLUSIONS: Transmeatal low-level laser irradiation is effective for the treatment of tinnitus and some variables like age and job can affect the treatment outcome.
Photomed Laser Surg. 2008 Aug;26(4):349-53.
Efficacy of low-level laser therapy in Ménière’s disease: a pilot study of 10 patients.
Teggi R, Bellini C, Fabiano B, Bussi M.
Ear, Nose, and Throat Department, IRRCS San Raffaele Hospital, Vita-Salute University, Milan, Italy. firstname.lastname@example.org
OBJECTIVE: To assess the efficacy of low-level laser therapy (LLLT) for Ménière’s disease (MD).
MATERIALS AND METHODS: Twenty patients with unilateral MD were included in the study; all presented with uncontrolled vertigo. The patients were randomly divided into two groups: group 1 patients received LLLT 20 min a day with a 5-mW soft laser for 6 mo, while group 2 received betahistine 16 mg twice a day for 6 mo. According to American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) guidelines, the main outcome for vertigo control was considered to be the number of spells per month in the 6 mo before treatment compared with the same parameter in the 6 mo of therapy. The duration of spells expressed in minutes was also considered. Moreover, a hearing test was performed before and after therapy and results were reported as the pure tone average of 500-, 1000-, 2000-, and 3000-Hz frequencies. All results were valued at baseline, and after 3 and 6 mo of therapy.
RESULTS: Compared to baseline, the number and duration of spells were significantly reduced in both groups; statistical significance was detected for the 3-mo control in both groups (p 0.05 with the multiple pair comparison test). Betahistine seems to have a faster action in spell reduction (p 0.05 comparing the 3-mo results between the two groups). Audiometric examination did not show a statistically significant difference between the two groups.
CONCLUSIONS: In our experience, LLLT seems to prevent vertigo spells in MD, although results indicate that it has a slower action than betahistine. Dose-dependent therapeutic effects could explain the last result. In our opinion, increased blood flow in the inner ear is the main mechanism leading to the therapeutic results.
J Laryngol Otol. 2008 May;122(5):447-51. Epub 2007 Jul 12.
Effectiveness of transmeatal low power laser irradiation for chronic tinnitus.
Gungor A, Dogru S, Cincik H, Erkul E, Poyrazoglu E.
Department of Otolaryngology, Haydarpasa Military Hospital, Istanbul, Turkey.
OBJECTIVE: To evaluate effectiveness of 5 mW laser irradiation in the treatment of chronic tinnitus.
STUDY DESIGN: Prospective, randomised, double-blind study.Methods:This investigation included 66 ears in 45 patients with chronic unilateral or bilateral tinnitus. A 5 mW laser with a wavelength of 650 nm, or placebo laser, was applied transmeatally for 15 minutes, once daily for a week. A questionnaire was administered which asked patients to score their symptoms on a five-point scale, before and two weeks after laser irradiation. A decrease of one scale point, regarding the loudness, duration and degree of annoyance of tinnitus, was accepted to represent an improvement.
RESULTS: The loudness, duration and degree of annoyance of tinnitus were improved, respectively, in up to 48.8, 57.7 and 55.5 per cent of the patients in the active laser group. No significant improvement was observed in the placebo laser group.
CONCLUSION: Transmeatal, low power (5 mW) laser irradiation was found to be useful for the treatment of chronic tinnitus.
EMLA Laser Health J 2007;2:46-67
European Medical Laser Association (EMLA)
Combined non-invasive laser – Egb 761 therapy of chronic tinnitus
Head of ENT Clinic of the 3rd Medical Faculty, Charles University, Prague, CZ
The treatment of patients with chronic tinnitus is very problematic and therefore otologists are trying to discover more suitable courses of therapy. In this study we wanted to evaluate the outcome of using a combination of EGb 761 and soft laser therapy.
We examined 120 patients with an average duration of tinnitus of 10 years. The patients underwent pure-tone audiometry, speech audiometry and objective audiometry tests. The intensity and frequency of tinnitus was also determined. EGb 761 was administered 3 weeks before starting soft laser therapy. Patients underwent 10 sessions of laser therapy, each lasting for 10 min. An improvement in tinnitus was audiometrically confirmed in 50.8% of patients.
EMLA Laser Health J 2007;2:46-67
European Medical Laser Association (EMLA)
Lasers Med Sci. 2003;18(3):154-61
Transmeatal cochlear laser (TCL) treatment of cochlear dysfunction: a feasibility study for chronic tinnitus.
Tauber S, Schorn K, Beyer W, Baumgartner R.
Department of Otolaryngology, Head and Neck Surgery, Ludwig-Maximilians-University of Munich, D-81377 Munich, FRG. email@example.com
Low-level-laser-therapy (LLLT) targeting the inner ear has been discussed as a therapeutic procedure for cochlear dysfunction such as chronic cochlear tinnitus or sensorineural hearing loss. Former studies demonstrate dose-dependent biological and physiological effects of LLLT such as enhanced recovery of peripheral nerve injuries, which could be of therapeutic interest in cochlear dysfunction. To date, in patients with chronic tinnitus mastoidal and transmeatal irradiation has been performed without systematic dosimetric assessment. However, light-dosimetric studies on human temporal bones demonstrated that controlled application of laserlight to the human cochlea depends on defined radiator position within the external auditory meatus. This feasibility study first presents a laser application system enabling dose-controlled transmeatal cochlear laser-irradiation (TCL), as well as preliminary clinical results in patients with chronic cochlear tinnitus. The novel laser TCL-system, consisting of four diode lasers (lambda=635 nm-830 nm) and a new specific head-set applicator, was developed on the basis of dosimetric data from a former light-dosimetric study. In a preliminary clinical study, the TCL-system was applied to 35 patients with chronic tinnitus and sensorineural hearing loss. The chronic symptoms persisted after standard therapeutic procedures for at least six months, while retrocochlear or middle-ear pathologies have been ruled out. The patients were randomised and received five single diode laser treatments (lambda=635 nm, 7.8 mW cw, n=17 and lambda=830 nm, 20 mW cw, n=18) with a space irradiation of 4 J/cm2 site of maximal cochlear injury. For evaluation of laser-induced effects complete otolaryngologic examinations with audiometry, tinnitus masking and matching, and a tinnitus-self-assessment were performed before, during and after the laser-irradiation. The first clinical use of the TCL-system has been well tolerated without side-effects and produced no observable damage to the external, middle or inner ear. Changes of tinnitus loudness and tinnitus matching have been described. After a follow-up period of six months tinnitus loudness was attenuated in 13 of 35 irradiated patients, while two of 35 patients reported their tinnitus as totally absent. Hearing threshold levels and middle ear function remained unchanged. Further investigations by large double-blind placebo-controlled studies are mandatory for clinical evaluation of the presented TCL-system and its therapeutic effectiveness in acute and chronic cochlear dysfunction.
Hyperacusis treatment with a combination of laser therapy, pulsed electromagnetic field therapy and reactive oxygen speciment control.
Audio Laser-Kliniken, Danderyd, Sweden
In a clinical study, at Audio Laser-Kliniken, 26 hyperacusis patients with 42 “hyperacusick” ears were measured using audiometry before and after therapy. There were 7 patients/13 ears returning by random to the clinic 4-6 months after finished therapy for a long time follow up. 10-20 treatments (twice a week) per patient were performed.
The LASER light effect per session varied between 206.7-513.6 J per ear. 810-830 and 635-650 nm wavelength was administrated via meatus. Pulsed Electromagnetic Field Therapy was also used and Reactive Oxygen Specimen were measured and controlled by an additional intake of antioxidants per os. The average pain threshold improvement was for all 245 hyperacusis observations 17.02 dB. The mean value was 16.90 dB. The average improvement was 22.84 dB for 74 long time follow up observations (4-6 months after therapy). Until now there hasn’t been any known potent therapeutic method improving hyperacusis.
Patients with grave hyperacusis seem to have the largest dB-improvements from this therapy. The combined set of therapies in this study should be a first choice therapy for all hyperacusis patients.
Lasers in Surgery and Medicine. April 16-18, 1999. Supplement 11, 1999.
Report on more than eight years of low level laser therapy in chronic inner ear diseases.
Lutz Wilden, Sabine Schübel, Germany.
The IXX Annual Meeting of The American Society for Laser Medicine and Surgery, Lake Buena Vista, Florida.
348 patients (402 ears) were treated with low level laser. Most patients had tinnitus. This study, however, only reports on the objective outcome of the audiometry, taken before and after therapy. The hearing capacity of the patients was improved in all frequency sectors (average value = 20.6%). The best db-reductions were obtained in the low frequencty sector (11.7 db) and in the high frequency sector (14.6 db). There was a close correlation between the improvement of the hearing capacity and the age of the patients and the duration of their disease. In conclusion it can be stated that if LLLT is administered in sufficiently high dosages to the inner ear (cochlea), it is possible to obtain and document significant biostimulative effects.
ON THE EFFECTIVENESS OF LOW LEVEL LASER LIGHT (LLLL) IN THE INNER EAR
Reproduced here through the kind permission of Dr. Lutz Wilden
(db = decibel; j = joule; kc = kilocycle; nm = nanometer)
A) The objective of the study was the documentation of the biostimulative effects of LLLL in high energetical dosages (measured in j) by audiometry changes of a statistically relevant number of patients. B) The energy was transmitted with 3 laser diodes with a wave length of 830 nm and 3 diodes with a wave length of 635 nm; it was administered via meatus and mastoid. The examination and therapy included 348 patients and 215 right and 187 left inner ear organs (cochlea). 171 organs were female, 231 were male. Their average age at the beginning of the therapy was 56.9 years; the average duration of their disease was 5.9 years. 97.3 % suffered from tinnitus. The examination started on 24 june 1996 and ended on 9 february 1999. The average treatment phase lasted 61.5 days. The average duration of the therapy was 11.8 hours; the average quantity of the transmitted energy was 6732 j. Before every therapy series with LLLL the patients actual hearing capacity (air and bone conductions) was examined by audiometry. At the end of each therapy series their hearing capacity was examined by the same method for a second time. The statistical analysis consisted of the arithmetical evaluation of a mean value of all test data over 12 frequencies as far as air and bone conductions were concerned, the drawing up of frequency intervals (low = 0.125, 0.25, 0.5 and 0.75 kc, middle = 1, 1.5, 2 and 3 kc, and high = 4, 6, 8 and 12 kc) and the grouping of the patients according to age, duration of the disease, quantity of the transmitted energy and the relative total reduction of the necessary sound volume in db. In cases of deafness 125 db were used as an auxiliary numeric value. C) The hearing capacity of the patients was ameliorated in all frequency sectors (average value = 20.6 %). The best db-reductions were obtained in the low frequency sector (9.3 db) and in the high frequency sector (11.2 db). There was a close (and biologically plausible) correlation as far as the amelioration of the hearing capacity and the age of the patients and the duration of their disease were concerned; this correlation was the higher, the more energy was transfered on the whole. D) If LLLL is administered in sufficiently high dosages to the inner ear (cochlea), it is possible to obtain and document medicinically significant biostimulative effects.Introduction
According to a study of the university of Cologne1) by 2030 every second German will be suffering from impairments of the inner ear. Even at the present time, the number of people all over the world, who are inflicted with long-standing impairments or acute diseases of the inner ear, amounts to millions. The basic diagnostic for the documentation of the functional quality of the cochlea is the audiometry. The correlation of organopathological examinations of the cochlea and pathological audiometry results is illustrated by scientific papers2)
The audiometry belongs to the diagnostical standard equipment of medical offices and acousticians and is universally being used as a basic diagnostic by trade operative associations and industrial medicine for the purpose of examinations and appraisements. This is why it seemed approriate to use this method, which is both economical and easy on the patient, to verify the biostimulative effects of LLLL on the inner ear.Nowadays, the prevailing measures to give therapy to patients with a reduced hearing capacity are the administration of non-specific medicaments that stimulate the blood circulation respectively the utilization of technical equipment such as sound amplifiers (hearing aids) or – in severe cases – electronically operated artificial inner ear appliances.At present, a therapy that ameliorates the biological qualitiy of the sensory cells of the cochlea and thus increases the hearing capacity is being cold-shouldered by the overwhelming majority of physicians.Although the manifold clinical and experimental studies of the international low level laser literature3)4) and the penetration capacity of LLLL into the inner ear 5), so far there was no statistical inquiry about the therapy with high dosages of LLLL, which is backed up by a sufficient amount of audiometrical data and takes into account a statistically relevant number of patients respectively inner ear organs.
include examinations of the therapy of inner ear diseases
Material and methods
|The energy was transmitted by 3 laser diodes with a wave length of 830 nm und 3 diodes with a wave length of 635 nm; it was administered via meatus and mastoid. The statistical analysis consisted of the arithmetical evaluation of a mean value of all audiometrical data over 12 frequencies as far as air and bone conductions were concerned, the drawing up of frequency intervals (low = 0.125, 0.25, 0.5 and 0.75 kc, middle = 1, 1.5, 2 and 3 kc, and high = 4, 6, 8 and 12 kc and the grouping of the patients according to age, duration of the disease, quantity of the transmitted energy and the relative total reduction of the necessary sound volume in db. In cases of deafness 125 db were used as an auxiliary numeric value.|
|In the case of the initial audiometrical results (pretherapeutical findings) the evaluation of the mean value of all readings reveals a clearly reduced average course of the hearing curves of the air and bone conductions over all frequencies, with low points in the frequency sector around 6 kc and the frequency sector around 12 kc (sensorineural hardness of hearing, oblique descension).As expected, the bone conduction is situated above the air conduction in all frequencies. Occasional intersections of the air and bone conductions are only to be found in the frequency sector between 6 and 8 kc; this phenomenon, which is known from individual audiometries and can be observed on the mean curve, is due to an increasing loss of the differentiation capacity of the cochleas sensory cells within the range of higher-grade biological quality reductions of the organ of Corti.In the case of the final audiometrical results (posttherapeutical findings) the evaluation of the mean value of all readings reveals a clearly and symmetrically ameliorated average course of the hearing curves of the air and bone conductions over all frequencies as compared with the pretherapeutical course (amelioration of the sensorineural hardness of hearing with a reduction of the oblique descension). As expected, the bone conduction is once again situated above the air conduction in all frequencies; the intersection phenomena in the frequency sector between 6 and 8 kc show a downward tendency.|
|The diagram of the average total reduction (db) of the air and bone conductions shows a significant amelioration of the hearing capacity in the low and high frequency sector and a more pronounced amelioration of the air conduction as compared with the bone conduction in the lower frequency sector.Clinically, this can be interpreted to the effect that, apart from its general therapeutical value, the LLLL also exerts a positive influence on the widespread sound conduction disturbances in this frequency sector, which are indicated by degenerative changes of the middle ear (for instance, otosclerotic processes.)The highest reduction is to be found in the low frequency sector (9.3 db when there are 0.25 kc in the air conduction; 6.4 db when there are 0.124 kc in the bone conduction) and in the high frequency sector (10.9 db when there are 12 kc in the air conduction; 11.2 db when there are 12 kc in the bone conduction).
The average reduction (improved hearing) of the sound pressure necessary for the perception of sounds within a given frequency totals a mean value of 7.2 db over all frequenciesair(air = 7.8 db; bones = 6.7 db). Altogether, this corresponds with an average amelioration of the hearing capacity of<20.6 %(air = 20.5%;bones = 20.6%); for further figures compare appendix, table1.
|The comparison of all pre- and posttherapeutical readings over all frequencies reveals statistically highly significant results in the case of the air and bone conductions.The values of the air conduction, which are slightly higher as those of the bone conduction, indicate that the LLLL has additional positive therapeutical effects on the sound conducting structures of the middle ear.|
|The grouping of the readings according to age groups and 3 frequency intervals results in findings that are biologically plausible as far as both the air and the bone conductions is concerned. In other words, the patient group with the highest average age (72.4 years) finds itself in the most disadvantageous starting position; the patient group with the lowest average age (37.9 years) finds itself in the most advantageous starting position.This applies to all 3 frequency intervals. The data also show that – in spite of the respective starting position – all age groups profit from the biostimulative effects of the LLLL in a relatively equal way. This holds good for both the air and the bone conduction.If one takes into consideration the energy quantity (j) transmitted in order to reach these results, it is obvious that the eldest age group needs the largest quantity of transfered energy. However, this seems to be biologically plausible as well.|
|As to the grouping of the readings according to the duration of the disease and 3 frequency intervals, the patient group with the shortest duration of the disease (0.6 years) has the best initial values and obtains the best final results with the smallest quantity of transfered energy. The patient group with the longest duration of the disease (14.5 years) has the poorest initial values and furthermore needs the largest quantity of transfered energy. This holds good for both the air and the bone conduction over all frequencies. At the same time, a detailed analysis of the data reveals that – in spite of the respective duration of the disease – all patient groups profit from the biostimulative effects of the LLLL in a relatively equal way. It has to be emphasized, though, that once again the most difficult patient group (average duration of the disease 14.5 years) needed the largest quantity of transfered energy.|
|The grouping of the readings according to energy quantities reveals a clear correlation between the total quantity of the transfered energy and the therapeutical results that were obtained. The larger the quantitity of transfered energy, the higher the db-reductions that could be observed. This applies to both the air and the bone conduction in all 3 frequency intervals.|
Fig. 6b clearly shows the correlative (parallel) connection between the total quantity of transfered energy and the total reduction.
|Even if expressed in percentages, the mean values of the respective groupings demonstrate that the smallest amount of transfered energy (6188 j) results in the lowest relative reduction (5.4 %), whereas the largest quantitity of transfered energy (9007 j) brings about the highest relative reaction (46.4 %).The highest correlation coefficient of 0.91 (relative total reduction in relation to total quantity of transfered energy) thus confirms the observations implied by the foregoing groupings according to age, duration of the disease and total quantity of transfered energy.In the whole course of the therapy no side effects whatsoever could be observed.In some of the cases, however, the LLLT of the inner ear organ presented in this paper caused specific individual reactions such as temporary vertigo respectively the disappearance of an existing otogenic vertigo, the momentary appearance respectively disappearance of a sensation of pressure in the ear and changes respectively the reduction or disappearance of a prevailing dysacusia and/or tinnitus, which had to be interpreted correctly with regard to the patient.
If LLLL is transmitted to the inner ear (cochlea) in sufficiently high dosages, it is possible to obtain and document medicinically significant biostimulative effects.
In this respect, the results of the study at hand not only refer to the fundamental working model of the cellular energy transfer6) from 1998, which was based on quantum mechanics, but confirm its conclusions as well, namely, that cellular regeneration processes do take place, if the mitochondria in question are stimulated to an increased production of adenosine triphosphate (ATP) by sufficiently large quantities of LLLL.
To what extent subsequent LLLTs lead to additional organic betterments (on average > than 20.6 %) is left up to future studies. The same applies for an augmentation of the total quantity of the transfered energy in the course of the treatment phases or per unit; in the latter case further technological developements on the part of the laser industry are indispensable, though.
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5.- Wolfgang Beyer, Reinhold Baumgartner and Stefan Tauber (1997). Dosinetric analysis for low-level-lasertherapy (LLLT) of the human inner ear at 593nm and 633nm. Munich: Forschungsbericht der Ludwig-Maximilians-Universität
6.- Lutz Wilden and Rainer Karthein (1998). Import of Radiation Phenomena of Electrons and Therapeutic Low-Level Laser in Regard to the Mitochondrial Energy Transfer. Journal of Clinical Laser in Medicine and Surgery. 16 (3), pp. 159-165
Laser therapy in the combined treatment of hyperacusis, a prospective clinical study.
© 2005, ALIR Förlag
Patients suffering from hyperacusis were treated twice a week with a combination of therapeutic laser, pulsed electromagnetic field and the control and adjustment of Reactive Oxygen Species (ROS). 245 observations in 42 ears on 26 patients were measured before therapy and after 10-20 therapeutic sessions. One group was evaluated in short-term follow-up (immediately after therapy), another group was evaluated in long-term follow-up (4-6 months after therapy). The average improvement for the pain thresholds was 17.02 dB. An average improvement of 10 dB or more was obtained in 40 ears. In the long-term follow-up group the average result was 22.84 dB and in the short-time follow-up group it was 14.50 dB. All ears improved. Between 177-504 J of laser light was administrated via meatus acusticus. The pulsed electromagnetic field applicator generated a magnetic field of a maximum of 100 µT and it was placed behind the ear, over the area of the mastoid bone. ROS were measured and controlled by administrating different sorts of antioxidants such as Ginkgo biloba.
Low-energy laser radiation in the combined treatment of sensorineural hearing loss and Meniere’s disease
[Article in Russian]
Pal’chun VT, Lapchenko AS, Kadymova MI, Kucherov AG.
59 patients with neurosensory hypoacusis and 45 with Meniere’s disease underwent helium-neon laser intra- or supravascular radiation of blood. The treatment proved effective in acute neurosensory hypoacusis and Meniere’s disease. In chronic neurosensory hypoacusis the effect was insignificant.
Lasers Surg Med. 2001;28(1):18-26.
Lightdosimetric quantitative analysis of the human petrous bone: experimental study for laser irradiation of the cochlea.
Tauber S, Baumgartner R, Schorn K, Beyer W.
Department of Otolaryngology, Head and Neck Surgery, University of Munich, Germany. firstname.lastname@example.org
BACKGROUND AND OBJECTIVE: Application of laser irradiation targeting the inner ear has to be investigated for therapeutic effectiveness in cochlear injury and dysfunction. In vitro data demonstrate low-level laser-induced photochemical and photobiologic cell response, depending on cell type and irradiation parameters such as light dose. The aim of the presented study was to determine the light dose received by the cochlear hair cells by using different irradiation modalities for the human petrous bone.
STUDY DESIGN/MATERIALS AND METHODS: Lightdosimetric assessment was performed in human cadaver temporal bones (n = 13) after removing the cochlear membranous labyrinth. The external auditory meatus, the tympanic membrane (quadrants), and the mastoid bone were illuminated by a helium-neon laser (lambda = 593 nm) and diode lasers of different wavelengths (lambda = 635, 690, 780, and 830 nm). The spatial distribution of transmitted light in the cochlear windings was measured by means of a retrocochlearly positioned endoscopic CCD camera for image processing and was assigned to acoustic frequencies according to the tonotopic organization of the cochlea. For an estimation of the corresponding space irradiance in an intact cochlea, correction factors have been calculated by a Monte Carlo procedure on the basis of experimentally determined optical properties of skull bone.
RESULTS: The transmission of light across the tympanic cavity and the promontory depends strongly on wave-length of the laser and the position of the radiator. Transtympanal irradiation results in spatial intensity variations of a factor 4 to 10 within the cochlear windings. The space irradiance in an intact cochlea is 10 to 20 times the measured irradiance. For an irradiation of the mastoid, the light transmission within the cochlea is 10(3) to 10(5) times smaller compared with an irradiation of the tympanic membrane and is extremely variable for different specimens.
CONCLUSION: The strong dependence of the cochlear light distribution on various irradiation parameters demonstrates the impact of preclinical lightdosimetric investigations for effective individual laser irradiation of the human cochlea. Because of the observed spatial intensity variations, the optimal external light dose has to be chosen with regard to the tonotopy of the human cochlea. The obtained results are enabling us to apply defined laser light doses to different cochlear winding areas. Mastoidal irradiation leads to therapeutically insufficient light doses within reasonable treatment times, whereas transmeatal irradiation is recommendable. Further studies are mandatory for development of clinical devices for transmeatal irradiation of the cochlea.
Comprehensive therapy of patients suffering from tinnitus
Prochazka M, Tejnska R.
37 patients suffering from tinnitus (age 18-86 years) were treated in three ways: 1. Rehabilitation: mobilisation, physical training, physiotherapy. 2. Same as 1 but with placebo laser added. 3. Same as 1 but with functional laser added. Laser used was 830 nm 300 mW. 2-3 treatments per week were given, total 10 treatments. Treatment protocol: 90 J/cm2 CW on mastoideus, 45 J/cm2 5 Hz on mastoideus, 50 J/cm2 CW on acoustic duct, 25 J/cm2 5 Hz on acoustic duct. Tebokan Egb 761 ginko medication was added to treatment. Results were classified as no effect/less than 50% relief/more than 50% relief/no more tinnitus. The percentwise outcome for the three groups was: 1. 29.4/44.1/17.6/8.9 2. 25.8/48.4/25.8/0 3. 19.4/19.4/35.5/25.8
Auris Nasus Larynx. 1997; 24 (1): 39-42.
Promising results using LLLT for tinnitus and inner ear diseases
Shiomi et al. used a 40 mW GaAlAs laser in a group of 38 patients suffering from tinnitus, resistant to several medical therapies for more than six months. 21.6 J was given each time through the auditory meatus toward the cochlea. Ten treatments or more were given. Only 26% of the patients reported improved duration, but 58% had reductiont of loudness and 55% reduced annoyance. The authors conclude: ”Laser therapy seemed to be worth trying on patients with intractable tinnitus”. Editorial note: The results can be improved if much higher doses are given. Dr. Lutz Wilden of Bad Füssing, Germany reported on his 6 years of experience at a recent lecture before the members of the Swedish Laser Medical Society (Stockholm, May 1998). Dr. Wilden is using three different lasers. One is directed through the meatus, two are positioned over the mastoid. Total dosage 2000-4000 (sic) joules per treatment (60 minutes per session, 30 minutes per ear). Doses may seem very high, but the thick bone behind the ear absorbs about 95% of the energy before reaching the inner ear. For more info, see http://home.t-online.de/gbl-hc/ez.
TINNITUS AND VERTIGO – A CASE FOR THE DENTIST?
Jan Tunér DDS Grängesberg, Sweden. E-mail: email@example.com
The correlation between tinnitus/vertigo and cranomandibular disorders (CMD) has been known for quite some time, yet few dentists seem to be aware of this. It is not natural for the dentist to ask, nor for the patient to inform the dentist about such a situation since it does not appear to be a dental indication. However, quite a number of tinnitus/vertigo patients will be releived of their symptoms if a proper CMD treatment is performed. Low level lasers have been used to treat tinnitus patients with reasonable success, if sufficient energy and suitable treatment technique is used. These lasers have also proved themselves successful in the treatment of CMD. It is obvious, therefore, that low level laser therapy is an appropriate treatment modality for the yet undefined subgroup of tinnitus/vertigo patients with a CMD background. Laser therapy will reduce pain levels, ease muscular spasms and revert the vicious circle. In some cases laser therapy alone will produce astonishing results, in others it has to be combined with traditional occlusal stabilisation procedures. It is important for doctors to be aware of this subgroup of tinnitus patients since traditional therapies, and even laser therapy of the inner ears, will be ineffective if the CMD is not diagnosed and treated. This presentation will look at the literature documentation for laser therapy of tinnitus/vertigo.
Light dosimetry and preliminary clinical results for low level laser therapy in cochlear dysfunction
Beyer W et al.
The light distribution inside the cochlear windings produced by irradiation of the tympanic membrane was quantitatively measured ex vivo for wavelengths of 593, 612, 635, 690, 780 and 805 nm by means of video dosimetry. The transmission of light across the tympanic cavity and the promontory depends strongly on the wavelength. Spatial intensity variations of a factor of 10 and more inside the cochlear windings have been measured. The clinical study was performed with 30 patients suffering from chronic permanent tinnitus. 5 irradiations within 2 weeks each with a space irradiation of 4J/cm2 were applied at the cochlear position to be treated. Diode lasers of 635 or 830 nm, 15 patients each, were used. During and after irradiation there was no significant change of hearing. However, 40% of the patients reported a slight to significant attenuation of the tinnitus loudness of the treated ear. There was no difference between the two wavelength groups. A double blind controlled study is in preparation.
Otology & neurotology 2002; 23 (3): 296-300.
Transmeatal low-power laser irradiation for tinnitus.
Nakashima T, Ueda H, Misawa H et al.
To evaluate effectiveness of 60mW laser irradiation in the treatment of tinnitus. Prospective, randomised double-blind study. This investigation included 68 ears in 45 patients with disabling unilateral or bilateral tinnitus. The active or placebo laser treatment was administered trans-meatally once a week for 6 minutes. Laser irradiation was performed four times during a 4-week period. A questionnaire was administered to evaluate the loudness, duration, quality, and annoyance of tinnitus before and after irradiation. The loudness and pitch match for tinnitus were obtained, and distortion product otoacoustic emissions were also examined.: No significant difference was observed between the active and placebo laser groups with regard to outcome of loudness, duration, quality, and annoyance of tinnitus. In one patient who received active laser treatment, acute hearing deterioration occurred after the third irradiation. Transmeatal low-power laser irradiation with 60 mW is not effective for the treatment of tinnitus.
Used by the kind permission of the Czech Society for the Use of Laser in Medicine, www.laserpartner.org
The Role of LLLT in Treatment of Tinnitus
Laser Partner, 26.2.2002
Miroslav Prochazka, M.D.
Head doctor of the Jarov Private Rehab Clinic, Prague, CZ firstname.lastname@example.org
Comprehensive laser rehabilitation therapy of tinnitus has proven successfull and beneficial for treatment of this widespread civilization disease. Its long-term results are convincing, bringing significant relief to 36 per cent of patients and even leaving remarkable 26 per cent of patients without any symptoms (see Miroslav Prochazka, Ales Hahn: Comprehensive Laser Rehabilitation Therapy of Tinnitus: Long-Term Double Blind Study on a Group of 200 Patients in 3 Years, Laser Partner No. 51/2002). With the results mentioned above we can really speak about a breakthrough. This study brings an additional overview of the role of LLLT (Low Level Laser Therapy) in the treatment. Our results enable us to pinpoint laser as the leading element in the overall therapy of tinnitus.
Tinnitus is an auditory perception apearing without an objective sonic source from the outer environment. Tinnitus can be subjective (heard only by the patient) and objective (sound can be even heard also by others). Our study, however, deals with patients suffering from subjective tinnitus only. According to literature, fifteen per cent of entire population have experienced at least a tinitus episode some time, its incidence and severity rising with age up to approx. eighty-five per cent of population older than 60.
Our clinic has been treating tinnitus for more than 5 years. We have published three studies on this particular issue, and we are of the opinion that our results are being followed in several countries (Brasil, Cyprus, Sweden, Switzerland, Slovakia, Turkey, Japan, Germany etc.) and implemented in numerous clinics with significant results. Studies published by these clinics show results which are almost identical with our experience.
Our last study on a group of 200 patients in the course of three years was finalized in February 2002 and published in June 2002. Since there have always been efforts to evaluate an exact role of LLLT in treatment of tinnitus, apart from medication and physiotherapeutic manipulation of neck vertebra as an integral part of the comprehensive therapy, we have decided to create a separate group of patients to be treated only with laser. This was only possible thanks to our vast experience and long involvement in tinnitus treatments.
Materials and methods
Our group consisted of 72 patients, 49 males, 23 females, age ranging between 16 to 92 years. The age and sex is given in Table 1.
|SEX / AGE||16 – 20||21 – 30||31 – 40||41 – 50||51 – 60||61 +|
Prior to the application of LLLT, all the patients underwent the following pre-therapy examination:
1. Anamnesis (aimed especially at the fact whether tinnitus was caused by an acoustic trauma, as well as at genetic predisposition)
2. Subjective evaluation of suffering
3. Clinical examination (otoneurology, axial skeleton, nystagm, blood pressure)
4. Technical examination (audiogram, x-ray of neck vertebra, ENG, tinnitometry)
5. Laboratory testing
Audiograms were taken in all the patients prior to the therapy. After the therapy audiograms were taken in 62.5 per cent, i. e. 45 patients, showing a slight improvement. Audiogram provides only for numeric range of perception of frequency of sounds, however it does not give us an objective evaluation of quality of hearing. Furthermore, the patients do not see the main improvement in a wider range of frequency of sounds, this remains usually on a similar level, but the main benefit is the absence of the additional burdening sound caused by tinnitus. Therefore the patients can better analyze sounds in general, their hearing is “refreshed” as they usually describe the result of the therapy.
Typical audiograms of patients with tinnitus before and after therapy shown on Picture 1.
MAESTRO/CCM device (manufactured by MediCom, Prague) was used for the study, with an infrared laser probe (830 nm) and power output 300 mW. The following application dosages and frequency modulations were applied on the following points:
1. meatus acusticus externus – in the direction of the axis of the auditory duct – continuous beam 50 J/cm2 followed by 25 J/cm2, frequency modulation of 5 Hz (Picture 2),
2. processus mastoideus – directed on the center, the vector of the beam in the direction of counter-lateral orbit, continuous beam 90 J/cm2 , followed by 45 J/cm2 with 5 Hz pulse frequency (Picture 3).
We strictly appeal to maintain the direction of the vector of aiming the beam – in fact the target structure of the helix is a shape of several square milimeters.
At the beginning, attendance was scheduled to 10 procedures in total, twice a week. Having completed the first series, patients returned after 2 – 3 months for another two series, each consisting of 5 – 6 therapies, once a week.
Level of subjective complaints was evaluated according to three scales:
- Percentage scale – complaints evaluated 100 per cent at the beginning of therapy (Blue), according to the level of relief decreased (Green) to 80, 70 etc. per cent, possible acceleration of problems (Red) goes up to 110, 120 etc. per cent, no tinnitus equals 0 per cent
- Five-grade scale – analogous to pain scales, reaching from Gr. I = No tinnitus to Gr. 5 = tinnitus interfering all activities
|Grade I = No tinnitusGrade II = No interfering sound perceived during the day, only in evenings, causing no discomfortGrade III = Interfering sound perceived during the day, interrupting drowse onlyGrade IV = Interrupting drowse and sleep, interfering sound causing discomfort during the dayGrade V = Unbearable discomfort, interfering all activities|
- Graphic scale – Patient marking 0 to 10, accompanied by a simple graphics showing face grimaces according to his/her amount of subjective hardship.
In order to simplify the effect of therapy as much as possible the results were divided in four groups:
- Patients with no effect of comprehensive therapy
- Less than 50 per cent relief
- More than 50 per cent relief
- No more tinnitus, patient free of the disease.
This evaluation is identical with our previous study, and it enabled us to compare easily the results of both studies.
The results obtained are shown in Table 2.
|Less than 50 % relief||19||26.4|
|More than 50 % relief||22||30.6|
|No more tinnitus||16||22.2|
It was interesting to compare our latest results (LLLT only) with those of our previous studies, i. e. our study made in 1998, long-term study between 1999 – 2001, and the initial study aimed at LLLT only. Comparison is contained in Table 3.
|Result||1998||1999 – 2001||LLLT only|
|No effect||19.4 %||16.0 %||20.8 %|
|Less than 50 % relief||19.4 %||15.0 %||26.4 %|
|More than 50 % relief||35.5 %||43.0 %||30.6 %|
|No more tinnitus||25.8 %||26.0 %||22.2 %|
Hippocratic Oath orders us to treat patients to the best of our knowledge and ability. Since our long-term experience in comprehensive treatment of tinnitus has been based on the triad of physiotherapeutic manipulation, medication, and LLLT, we were at a loss whether we would not harm our patients in a way, giving them only a part of the treatrment, mere LLLT. We have to declare, that we have selected patients during the introductory examination, sorting out patients whose x-ray indicated a possibility of tinnitus caused by vertebral blockades. On the other hand, this selection led to a more pure evaluation of the role of LLLT in the treatment of tinnitus, leaving out both a possible cause and a corresponding treatment.
We have been positively surprised that in general the ratio of individual four groups remained similar. The number of patients with no effect of LLLT slightly increased (by 4.8 per cent when compared to the long-term study, by 1.4 per cent in comparison to the original study of 1998). This is obviously caused by the absence of medication and physiotherapy, showing their supportive efect.
In the group evaluating improvement as less than 50 per cent the leading role of LLLT can be evidenced best. More than one-fourth of all patients (26.4) report improvement after therapy performed with LLLT only, which is a result better than those in both previous studies (19.4 and 15.0) .
Impressive results have also been obtained in the last two groups , when we imagine more than one half of all patients reporting significant and/or total relief of tinnitus (30.6 + 22.2 = 52.8 per cent).
22.2 per cent patients suffering from tinnitus never more after treatment with therapeutic laser is a great success of LLLT. It only confirms the leading role of LLLT within comprehensive laser rehabilitation therapy of tinnitus. On the other hand we must stress the necessity to apply the two remaining parts of our therapeutic triad as well, since medication and physiotherapeutic manipulation are integral parts of the general care of our patients, and we should not deprive the suffering of the means and methods capable of bringing them more relief, which we are aware of.
Literature and references
- Tejnska, R., Prochazka, M.: Non Invasive Laser in Therapy of Tinnitus, Laser Partner 4/2000, Prague 2000.
- Simunovic, Z. et al.: Lasers in medicine and dentistry, Vitagraf Rijeka, 2000. Hahn, A. et al.: Combined Laser – Egb 761 Tinnitus Therapy, Acta Otolaryngol 2001, Suppl. 545, 92-93.
- Shiomi, Y. et al.: Efficacy of Transmeatal Low Power Laser Irradiation on Tinnitus: a preliminary report, Auris Nasus Larynx, 1997, 24, 39-42.
- Chomete, G. et al.: Effect of the Laser on Gingival Tissue. I. J Biol Buccale 1987, 15, 45-49.
- Tunér, J., Hode, L.: Low Level Lasertherapie Clinical Practice and Scientific Background, Grängesberg 1999.
- Petrek, M., Hubacek, J., Ordeltova, M.: Innunomodulatory Effects of Lasertherapy in the Treatment of Chronic Tonsilitis, Acta Universitatis Palackianae Olomucensis, T. 129, 1991.
- Hubacek, J.: Experience with the Use of LLLT in ENT Medicine, Laser Partner 22/2000, Prague 2000
- Prochazka, M.: Case Histories of Patients Suffering from Tinnitus Treated by Comprehensive Rehabilitation Therapy incl. LLLT, Laser Partner 40/2001, Prague 2001.
- Prochazka, M., Hahn, A.: Comprehensive Laser Rehabilitation Therapy of Tinnitus – Long-Term Double Blind Study on a Group of 200 Patients in 3 Years, Laser Partner 51/2002, Prague 2002.
- Declaration von Helsinki des Weltarztsbundes, Pharm. ind. 52, 1990, 12, 1497 – 1498.
- Wilden, L., Dindiger, D.: Treatment of Chronic Complex Diseases of the Inner Ear, Laser Therapy 4/1996.
- Ohshiro, T., Ogata, H., Yoshida, M. et al: Penetration Depths of 830 nm Diode Laser Irradiation in the Head and Neck Assessed Using a Radiography Phantom Model and Wavelength-specific Imaging Film, Laser Therapy 8/1996