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Table of Content - Volume 14 Issue 2 - May 2020

 

 

Comparison of OAE profile in individuals with normal hearing with tinnitus and individuals with normal hearing without tinnitus

 

Shiv Kumar1, Sidharth Sharma2*, Shashikant Kumawat3, Tvarita4

 

1Sr. Professor & HOD, 2IIIrd Year Resident, 3,4Resident, Department of ENT, Government Medical College Kota, Rajasthan, INDIA.

Email: sharmasidharth386@gmail.com

 

Abstract               Background: Tinnitus is an auditory sensation whose source comes from external stimulus to the body. The aim of this study was to investigate the possible role of cochlear outer hair cells function with TEOAE and DPOAE test in patient with normal hearing having tinnitus. Materials And Method: A total of 100 subjects (age range of 18-60 years) participated in the study and were catergorized into two groups(study and control). The study group included 50 individuals with normal hearing having tinnitus and control group includes 50 individuals with normal hearing without tinnitus. The TEOAE were recorded with click stimulus at 1000,2000,3000,4000 Hz and DPOAE were measured with two frequency (range 1 – 4 kHz and ratio between f1 and f2 was 1.2) and intensity of L1=55 dB-SPL and L2=65 dB-SPL. Results And Conclusion: according to our results mean amplitude of TEOAE and DPOAE in control group were greater than study group but this difference was statistically non significant. In conclusion of our results could provide that there was no evidence of an association of tinnitus and outer hair cells activities.

 

INTRODUCTION

An otoacoustic emission (OAE) is a sound which is generated from within the inner ear. Having been predicted by Thomas Gold in 1948, its existence was first demonstrated experimentally by David Kemp in 1978. OAEs are considered to be related to the amplification function of the cochlea. In the absence of external stimulation, the activity of the cochlear amplifier increases, leading to the production of sound. Several lines of evidence suggest that, in mammals, outer hair cells are the elements that enhance cochlear sensitivity and frequency selectivity and hence act as the energy sources for amplification. Broadly speaking, there are two types of otoacoustic emissions: spontaneous otoacoustic emissions (SOAEs), which can occur without external stimulation, and evoked otoacoustic emissions (EOAEs), which require an evoking stimulus.

Types

Spontaneous

Spontaneous otoacoustic emissions (SOAE)s are sounds that are emitted from the ear without external stimulation and are measurable with sensitive microphones in the external ear canal. At least one SOAE can be detected in approx. 35-50% of the population. The sounds are frequency-stable between 500 Hz and 4500 Hz to have unstable volumes between -30 dB SPL and +10 dB SPL. The majority of the people are unaware of their SOAEs; portions of 1-9% however perceive a SOAE as an annoying tinnitus.

Evoked

Evoked otoacoustic emissions are currently evoked using three different methodologies.

  • Stimulus Frequency OAEs (SFOAEs) are measured during the application of a pure-tone stimulus, and are detected by the vectorial difference between the stimulus waveform and the recorded waveform (which consists of the sum of the stimulus and the OAE).
  • Transient-evoked OAEs (TEOAEs or TrOAEs) are evoked using a click (broad frequency range) or toneburst (brief duration pure tone) stimulus. The evoked response from a click covers the frequency range up to around 4 kHz, while a toneburst will elicit a response from the region that has the same frequency as the pure tone.
  • Distortion product OAEs (DPOAEs) are evoked using a pair of primary tones and  with particular intensity (usually either 65 - 55 dBSPL or 65 for both) and ratio.

 

AIMS AND OBJECTIVES

  • To evaluate the comparison of OAE profile in individuals with normal hearing having tinnitus and individuals with normal hearing without tinnitus.
  • To study the OAE profile in tinnitus patients.
  • To evaluate the outer hair cell function in tinnitus patients.

 

MATERIALS AND METHODS

This was a case control study performed from December 2017 to March 2019 at the department of Otorhinolaryngology, Govt Medical College and attached group of medical college Kota.

Method Subjects: A total of 100 (52 males and 48 females) subjects in the age range of 18 to 60 years participated in the study. They were categorized into two groups:

    • Study group and
    • Control group.

Clinical group included 50 individuals (26 males and 24 females) with tinnitus having normal hearing.

While control group: This group had 50 individuals (26 males and 24 females) with normal hearing, without tinnitus.  All subjects in the clinical group had tinnitus either in one ear or both the ears. Subjects in both the group had pure tone thresholds within 15 dB HL in octave frequencies from 250 Hz to 8 kHz for air conduction. They had no history of exposure to noise or ototoxicity which might cause hearing loss. No observable neurological symptoms or any other general body weakness noticed or reported. None of them reported to have any history of ear pain, ear discharge and giddiness. Subjects in the clinical group had “A‟ type tympanogram with presence or absence of acoustic reflexes. While in the control group subjects had “A‟ type tympanogram with presence of acoustic reflexes. All Audiological evaluations and recording of OAEs were carried out in a sound treated room. The ambient noise was within the permissible limits as recommended by ANSI (S3.1, 1991).

PROCEDURE

To obtain the data from both the clinical and control group, the whole study was carried out in two phases.

Phase 1 included physiological assessment which was done in both clinical and control group participated.

Phase 2 included psychoacoustic assessment of tinnitus which involved pschocoustic tinnitus evaluation (pitch matching and loudness matching) and was done only in the clinical group.

INCLUSION CRITERIA: Patient having confirm diagnosis of tinnitus for >3 months with normal hearing levels.(<25dB). Patients having normal A type of tympanogram. Patient age from 18-60 years. Patients having normal anatomy of ear and tympanic membrane

EXCLUSION CRITERIA: Patients having tinnitus for < 3 months. Patients age <18 years and > 60 years. Patients with conductive or sensineural hearing loss (>25dB). Patients having ontological diseases (otitis media,fluid in middle ear,otosclerosis,tumors of external ear etc). Patients having congenital abnormality of ear (anotia,microtia,congenital absence of ossicles etc). Patients having tympanogram other than A type (like As type , Ad type , B type, C type). Patients having any systemic and chronic diseases              (diabetes,HTN,carcinoma etc)

OBSERVATIONS AND RESULTS

 

Table 1: GENDER WISE DISTRIBUTION

Subject

No. of Subject who had tinnitus in one year

No. of Subject who had tinnitus in both Ear

Male

22

4

Female

18

6

Total

40

10

 

 

Table 2: Tinnitus Frequencies (Pitch Matching)

Frequencies of tinnitus by pitch matching

No.of ear (%)

8 kHz

27 (45%)

4-8 kHz

20 (34%)

< 4 kHz

13 (21%)

 

Table 3: Loudess of tinnitus (loudness matching)

Loudness matching(dB) and degree

No. of ears(%)

0-15 dB (mild)

15

16-30 dB (moderate)

40

31-45 dB (severe)

5

 

Table 4: No. and Percentage of Ear that have reffer and pass TEOAE in Study group and Control Group

Group

Total Ear

TEOAE (PASS)

TEOAE (Reffer)

P Value

Study Group

60

46 (76%)

14 (24%)

0.0672

Control Group

100

94 (94%)

6 (6%)

 

Table 5: No. and Percentage of Ear that have reffer and pass DPOAE in Study group and Control Group

Group

Total Ear

DPOAE (PASS)

DPOAE (Reffer)

P Value

Study Group

60

38 (64%)

22 (36%)

0.0997

Control Group

100

88 (88%)

12 (12%)

 

Table 6: Mean and SD of TEOAE with patient tinnitus in right ear in study group and control group

TEOAE and Ferqence

GROUP

MEAN

SD

P Value

TEOAE 1000 HZ

Study Group

4.1

5.63

0.0253

Control Group

6.84

4.68

TEOAE 2000 HZ

Study Group

4.77

5.54

0.7785

Control Group

4.37

6.75

TEOAE 3000 HZ

Study Group

4.07

6.23

0.9187

Control Group

4.22

6.76

TEOAE 4000 HZ

Study Group

0.88

8.2

0.0757

Control Group

4.09

7.68

 

Table.7: Mean and SD of TEOAE in patient tinnitus in Left ear in study group and control group

TEOAE and Ferqence

GROUP

MEAN

SD

P Value

TEOAE 1000 HZ

Study Group

3.42

8.72

0.0199

Control Group

6.98

4.53

TEOAE 2000 HZ

Study Group

5.03

6.39

0.6095

Control Group

5.82

6.49

TEOAE 3000 HZ

Study Group

3.15

7.3

0.1038

Control Group

5.892

6.74

TEOAE 4000 HZ

Study Group

-0.33

7.56

0.8148

Control Group

0.156

9.36


Table 8: Mean and SD of DPOAE with patient tinnitus in right ear in study group and control group

DPOAE and Ferqence

GROUP

MEAN

SD

P Value

DPOAE 1.7KHZ

Study Group

4.7

6.74

0.229

Control Group

6.3

5.14

DPOAE 2.1KHZ

Study Group

3.46

7.18

0.0107

Control Group

7.26

5.93

DPOAE 3.3KHZ

Study Group

1.35

7.95

0.0021

Control Group

6.35

6.28

DPOAE 4.2KHZ

Study Group

0.73

9.01

0.0774

Control Group

3.9

6.99

 

 

Table 9: Mean and SD of DPOAE in patient tinnitus in Left ear in study group and control group

DPOAE and Ferqence

GROUP

MEAN

SD

P Value

DPOAE 1.7KHZ

Study Group

5.95

7.27

0.9497

Control Group

6.04

5.13

DPOAE 2.1KHZ

Study Group

5.41

7.67

0.2339

Control Group

7

4.03

DPOAE 3.3KHZ

Study Group

2.36

8.05

0.0188

Control Group

6.24

5.97

DPOAE 4.2KHZ

Study Group

1.8

9.45

0.7237

Control Group

2.48

7.27

 

Table 10: Mean and SD of TEOAE and DPOAE in patient tinnitus in right ear in study group and control group

OAE

GROUP

MEAN

SD

P Value

 

TEOAE Right Ear

Study Group

3.45

1.74

0.2398

Control Group

4.88

1.31

DPOAE Right Ear

Study Group

2.56

1.84

0.0273

Control Group

5.95

1.43

 

Table 11: Mean and SD of DPOAE in patient tinnitus in Left ear in study group and control group

OAE

GROUP

MEAN

SD

P Value

TEOAE Left Ear

Study Group

2.817

2.25

0.3597

Control Group

4.711

3.08

DPOAELeft Ear

Study Group

3.88

2.1

0.3253

Control Group

5.44

2.01

 

DISCUSSION

The Present study was conducted on 100 patients divided into two groups of study and control according to their complains and hearing status selected in the Department of ENT , M.B.S Medical College , Kota. Table no.1: Shows that 40 patients had tinnitus in one ear (22 male 18 female) and 10 patients had tinnitus in both ears (4 males 6 females). Thus there is no significant difference regarding gender between the two groups. The study conducted by Maryam Emadi, Mohammad Rezaei, SirvanNajafi, Ali Faramarzi, and Farhad Farahani shows that females had greater amplitude in TEOAE and DPOAE but there was no significant difference regarding gender and age between the two group. Distribution of perceived tinnitus frequencies in 60 ears (tinnitus ear) of the study group. These frequencies were obtained from pitch matching and was calculated and seen Table no.2 which shows that 27 ears(45%) had tinnitus of frequency 8 kHz and 20 ears(34%) had tinnitus of 4-8 kHz and 13 ears(8%) had tinnitus of < 4 kHz. The result shows that all selected patients had tinnitus. Table no 3 shows loudness of tinnitus after loudness matching.The obtained results were : 15 ears (25 %) had mild degree of tinnitus (0-15 dB) 40 ears(67%) had moderate degree of tinnitus (16-30 dB) And 5 ears (8%) had severe degree of tinnitus (31-45 dB) Thus all selected patients had tinnitus. Table no. 4 and 5: Table no. 4 shows that TEOAE in 94% of the control group and 76% in study group was normal and TEOAE in 6% in control group and 24% in study group showed reffer (p=0.0672). Thus there is no significant difference between the two groups. Table no.5 shows that DPOAE in 88% of the control group and 64% of the study group was normal and DPOAE in 12% of the control group and 36% of the study group showed refer(p=0.0997),but there was no significant difference between the two groups. The study conducted by Maryam Emadi, Mohammad Rezaei, SirvanNajafi, Ali Faramarzi, and Farhad Farahani showed the same result i.e the mean amplitude of TEOAE and DPOAE in control group were greater than that of study group but this difference was statiscally non significant. Table no. 6 and 7: Table no.6 shows: Mean and SD of TEOAE in patients having tinnitus in right ear in study and control group. Table no.7 shows : Mean and SD of TEOAE in patients having tinnitus in left ear in study and control group.In Table no.6and7 TEOAE in both ear at 1000 Hz is statsically significant (p=0.0253 right ear and p=0.0199 left ear) but at the frequency 2000 ,3000,4000 Hz TEOAE in both ears showed no significant difference between the study and control groups. The study conducted by Dhanya M.1 and Barman A.2 also showed that TEOAE statistically was not significant between the two groups at various frequencies. Table no.8 and 9: Table no.8 shows : Mean and SD of DPOAE in patients having tinnitus in right ear in study and control group. Table no. 9 shows : Mean and SD of DPOAE in patients having tinnitus in left ear in study and control group. DPOAE were measured using frequency f1 and f2 and ratio between f1 and f2 is 1.2 and DPOAE was eliciated at 1.7 kHz, 2.1kHz , 3.3kHz, 4.2 kHz and DPOAE amplitutde obtained from right and left ear for both the groups showed that DPOAE at 2.1 kHz for both the groups(p=0.0107) and DPOAE at 3.3 kHz for both the groups(p=0.0021) showed statsiscally significant difference between the two groups for right ear (Table No. 8). DPOAE at 1.7 kHz and 4.2 kHz was statsiscally not significant for both the groups in right ear.DPOAE at 3.3 kHz for both the groups (p=0.0188) in left ear showed statsiscally significant difference for both the groups (Table no. 9). DPOAE at 1.7 kHz , 2.1 kHz, 4.2 kHz was statsiscally not significant for both the groups in let ear.The study conducted by Dhanya M.1 and Barman A.2 also reported same result where there was nosignificant difference for DPOAE and mean value of DPOAE if higher in control group than in study group. Table no.10 and 11 :Table no. 10 shows : mean and SD of TEOAE and DPOAE in patient tinnitus in right ear in study group and control group.Table no. 11 shows : mean and SD of TEOAE and DPOAE in patient tinnitus in left ear in study group and control group.Table no.10 : DPOAE in right ear show significant difference (p=0.0273) between the study and control group but TEOAE in both ear and DPOAE in left ear showed no significant difference between the study and control group. The study conducted by Maryam Emadi, Mohammad Rezaei, SirvanNajafi, Ali Faramarzi, and FarhadFarahani showed almost the same result where DPOAE in one ear showed significant and TEOAE for both ear and DPOAE in one ear showed no significant difference for both the study and control groups.

 

SUMMARY AND CONLUSION

The present study was conducted in dept. of Otorhinolaryngology MBS Hospital Govt. Medical College Kota Rajasthan from Dec 2017 – March 2019. After approval of study protocol by the Local Ethical Committee and obtaining fully informed consent from the patients of 18-60 years of age and do comparision of OAE profile (TEOAE and DPOAE) in the study and control group. In study group 50 patients having tinnitus in one or both the ears with normal hearing and in control group 50 normal individuals having normal hearing without tinnitus.

The study revealed following results

  1. The TEOAE in 94% control group amd 76% study group was normal with not significant difference between the two groups(p=0.672). The DPOAE in 88% control group and 64% study group was normal and the difference statistically was not significant(p=0.0997).
  2. According to our results mean amplitude of TEOAE and DPOAE in control group were greater than study group but this difference was statistically not significant.
  3. According to our results DPOAE in right ear shows significant difference (p=0.0273)between the study and control group and TEOAE in the both ear and DPOAE in the left ear shows no significant difference between the study and control group.

 conclusion of our results could provides that no evidence for an association between tinnitus and the outer hair cell activities because in our study the difference was statistically not significant for both DPOAE and TEOAE. But the mean amplitude of TEOAE and DPOAE in control group is greater than study group which show that outer hair cell of the cochlea may be involved in the generation of tinnitus. Following the possible role of OHC damage or dysfunction of the cochlear efferent system in tinnitus subject may required more than 4 (6 or 8) freqencies in the future studies.

 

REFERENCES

  1. American National Standards Institute (1991). Maximum permissible ambient noise levels for audiometric test rooms. ANSI S3.1. New York: American National Standards Institute.
  2. American Speech-Language-Hearing Association. (2005). Audiology Information Series retrieved from http://www.asha.org /public/hearng /disrders/Tinnitus.
  3. Ami M, Abdullah A, Awang MA, Liyab B, Saim L (2008) Relation of distortion product otoacoustic emission with tinnitus. Laryngoscope 118(4):712–717
  4. Attias, J., Bresloff, I., and Furman, V. (1996). The Influence of the Efferent Auditory System on Otoacoustic Emissions in Noise Induced Tinnitus: Clinical Relevance .ActaOto- Laryngologica, 116(2), 534539.
  5. Axelsson, A., andRingdahl, A. (1989). Tinnitus-a study of its prevalence           and characteristics. British Journal of Audiology, 23(1), 53-62.
  6. Andersson G, Eriksson J, Lundh L-G, Lyttkens L (2000) Tinnitus and cognitive interferenceA stroop paradigm study. J Speech Lang Hear Res 43(5):1168–1173.
  7. Assaf S, Jamous NA, Hroot A, Tubishi K, Husban A, Hamasha K et al.. (2010) Otoacoustic emissions and tinnitus in normal hearing. JRMS 17(2):27–31
  8. Auris Nasus Larynx. 2010 Feb;37(1):55-60. doi: 10.1016/j.anl.2009.05.001.
  9. Epub 2009 Jun 26.DPOAE in estimation of the function of the cochlea in tinnitus patients with normal hearing.
  10. Cazals, Y., andNegrevergne, M., and Aran, J.M. (1978). Electrical stimulation of the cochlea in man: hearing induction and tinnitus suppression. Journal of the American Audiology Society, 3(5), 209-213.
  11. Ceranic, B.J., Prasher, D.K., andLuxon, L. M. (1995). Tinnitus and Otoacoustic Emissions. Clinical Otolaryngology, 20,192-200.
  12. Coles, R.R. (1981). Epidemiology of Tinnitus. In Ciba Foundation symposium. London, Pitman Books Ltd. (16–34).
  13. Davis, A. (1989). The prevalence of hearing Impairment and reported hearing disability among adults in Great Britain. International Journal of        Epidemiology, 18, 911-917.
  14. Dhanya M.1 and Barman A.2: OAE Profile in normal hearing individuals with tinnitus 53 OAE Profile in Individuals with Tinnitus having Normal Hearing Sensitivity.
  15. Emadi M,et al.. Indian Journal of otolaryngology Head and Neck Surgery 2018Comparison of the Transient Evoked Otoacoustic               Emissions (TEOAEs) and Distortion Products Otoacoustic Emissions           (DPOAEs) inNormal Hearing Subjects With and Without Tinnitus.
  16. Fernanda Gentil,Susana Meirless, Thuane Roza, Marco Parente,        Eurico Almeida, Renato Natal : comparison of OAE in pateints with tinnitus having normal hearing vs mild hearing loss.
  17. Fechter LD, Gd C, Rao D (2002) Chemical asphyxiants and noise. NoiseHealth 4(14):49
  18. Fernandes, C., and Santos, T.M. (2009).Tinnitus and normal hearing: a study on the transient otoacoustic emissions suppression. Brazil Journal Otorhinolaryngology, 75(3), 414-419.
  19. Favero, M., Sanchez, G. T., Bento, R. F., and Ferreira, N. (2006). Contralateral suppression of otoacoustic emission in patients with tinnitus. RevistaBrasileira de Otorrinolaringologia, 72(2), 8-11.
  20. Glattke, T. J., and Robinette, M. S. (2002). Transient evoked otoacoustic        emissions. In: M. S, Robinette, and T. J, Glattke. Otoacoustic emissions:        clinical applications. (2ed.) ,63-82, New York: Thieme,.
  21. Gore, G. (2006). Strategies for tinnitus evaluation. (74-94). ISHA monograph.
  22. Gorga, M.P., Neely, S.T., Ohlrich, B., Hoover ,B., Redner, J., and Peters,           J.(1997). From laboratory to clinic: a large scale study of distortion            product otoacoustic emissions in ears with normal hearing and ears         with       hearing loss. Ear and Hearing, 18(6), 440-455.
  23. Han, B.I., Lee, H.W.,andKim,T.Y.(2009).Tinnitus: characteristics, causes,          mechanisms,and treatments. Journal of Clinical Neurology, 5, 11-19.
  24. Gouveris H, Maurer J, Mann W (2005) DPOAE-grams in patients with acute tonal tinnitus. Otolaryngol Head Neck Surg 132(4):550–553
  25. Granjeiro RC, Kehrle HM, Bezerra RL, Almeida VF, Andre´ LS, Oliveira CA (2008) Transient and distortion product evoked otoacoustic emissions in normal hearing patients with and without tinnitus. Otolaryngol Head Neck Surg 138(4):502–506
  26. Henry, J.A., andMeikle, M. B. (2000). Psychoacoustic measures of tinnitus. Journal of American Academy of Audiology, 11, 138-155.
  27. Heller AJ (2003) Classification and epidemiology of tinnitus. Otolaryngol Clin N Am 36(2):239–248
  28. Igna CD, Schmidt LP, Smith M, Facchini L, Kang S (2004) Otoacoustic emissions in patients with tinnitus and normal hearing. Otolaryngol Head Neck Surg 131(2):P279
  29. Jastreboff P.J (1993). A neurophysiological approach to tinnitus: Clinical Implications. British Journal of Audiology, 27,7-17.
  30. Kaul, R., Mishra, S., Walmsley, S.L., Loutfy, M.R., Logue, K.J., and       Gold,     W.L.(2008). Otosyphilis in HIV- coinfected Individuals. A Case Series from Toronto, Canada. AIDS Patient Care STDS, 22(3), 213-          219. Lopes. F., and Carlos, R.C. (2005). Otoacoustic emissions. In:
  31. Kaltenbach JA (2011) Tinnitus: models and mechanisms. Hear Res 276(1):52–60
  32. Kemp DT (2002) Otoacoustic emissions, their origin in cochlear function, and use. Br Med Bull 63(1):223–241
  33. Kim JH (2006) Tinnitus in noise-induced hearing loss. Korean J Aerosp Environ Med 16(1):9–14
  34. Lopes For. O. (Ed.) Treaty of Speech. Sao Paulo.
  35. Martin, W.H, Folmer, R.L, Shi, Y., andEdlefsen, L.L. (2006). Tinnitus   sound therapy. In: Tyler RS, (Ed). Tinnitus treatment (176-186). New York: Thieme.
  36. Meikle, M.B. (1995). The interaction of central and peripheral mechanisms in tinnitus. In: J.A. Vernon, A.R. Moller. Allynand Bacon, Boston. Mechanisms of Tinnitus, (181-206).
  37. Mitchell, P., Sindhusake.,Doungkamol., Golding., and Philip (1993). Risk         Factors for Tinnitus in a Population of Older Adults: The Blue Mountains Hearing Study. Ear and Hearing, 24(6), 501-507.
  38. Morest, D., andYurgelun, T. D. (1979). Degeneration in the central auditory pathways after acoustic deprivation or over-stimulation in the cat. The Anatomical record, 193, 750.
  39. Mrena R, Savolainen S, Kuokkanen JT, Ylikoski J (2002) Characteristics of tinnitus induced by acute acoustic trauma: a long-term follow-up. Audiol Neurotol 7(2):122–130
  40. Mokrian H, Shaibanizadeh A, Farahani S, Jalaie S, Mahdi P, Amali A, Arian Nahad H: Iran J Otorhinolaryngol. 2014 Jan;26(74):19-24. Evaluation of distortion and transient evoked otoacoustic emission in tinnitus patients with normal hearing.
  41. Maryam Emadi, Mohammad Rezaei, Sirvan Najafi, Ali Faramarzi, and              Farhad Farahani: Comparison of the Transient Evoked Otoacoustic Emissions (TEOAEs) and Distortion Products Otoacoustic Emissions      (DPOAEs) in Normal Hearing Subjects With and Without Tinnitus.
  42. Noren˜a AJ, Farley BJ (2013) Tinnitus-related neural activity: theories of generation, propagation, and centralization. Hear Res 295:161–171

 

 

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