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INVESTIGATIVE PROFILE OF PATIENTS WITH A PROFOUND SENSORINEURAL HEARING LO S S Sandra

De

sa Souza

•

Christopher

Lobe

•

Pramod

ti............................... iiiiiiiiiiiiiiiiiiiii!iiiiiiiiiiiiiii i ~ 8~::,o:!!~:.~i<'::i::"": ~i~:;i~i~i~::;i~:#: :~i i~i<: fO~£::: ~:::::~:~i::~ ~ rorn:~:~ :~ ::: : ~ : ~: S:Ri ~!::~:: :were , : : ~::i:::::!:.su~ ~:: e : e t e d ::go: a : detade~L:h,.~:~:: ::: : ':~::to ases of bilateral profound sensori-neural loss in which the deafness was prelingual, perilingual or postlingual, were subjected to several investigations. A detailed history was first taken to dgtect the cause of dearness and a pure tone audiogram was carried out to assess the degree of hearing loss. Brain Stem Evoked R e s p o n s e Audiometry and Electrocochle0graphy were done to verily objectively the hearing threshold and the site of the lesion. These tests were followed by coronal polytomography of the temporal bones to assess the development of the external auditory canal, ossicles, semicircular canals and the

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Sandra De sa Souza, Hen. Consultant Christopher Lobe, Registrar Promad Sarode, Registrar

I

cochlea. Cases were also subjected to an aided audiogram using a powerful hearing aid and a cochlear nerve test to assess the function of the cochlear nerve as the patients were also subjects for cochlear implant selection. M a t e r i a l s & Methods 285 patients presenting with a profound bilateral sensori-neural hearing loss were investigated at Jaslok Hospital and Research Centre, Bombay from 1987 to 1989. The results of each test were recorded and tabulated after alloting each test a specific code. (Table No. I & I1).

We are grateful to Dr. Vijay Shah of the Audiology Dept., Dr. Mrs. P. N. Wadia of the Clinical Neurophysiology Dept. of Jaslok Hospital and research Centre, Bombay, and Dr. Pesi Unwalla, Consultant Radiologist for their assistance in this study.

By pure tone audiometry H T L was tested upto 120 dB as per A N S I 1969 calibration, a,nd this was followed by an aided audiogram using a powerful hearing aid to note any i m p r o v e m e n t in the threshold and speech discrimination. B E R A was done on a D I S A 1500 + recorder using square pulse waves at 10 clicks per sec and averaging 4000 responses. E e o c h G was carried out with st transtympanic needle electrode and square pulses of 10 per sec. with rarefaction and alternate clicks and averaging 256 responses. A series of coronal t o m o g r a m s of the temporal bones was subsequently performed.

H i s t . - - H i s t o r y - C o d e s - (Table I1) Lg. - - Lingual - Pre/Post - -

Address for reprints Dr. Sandra DesaSouza

Acknowledgements

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Department of Otorhinola~ngolo#, Jaslok Hospital & Research Cemre Bombay.

Desa's Hospital, 15, Dadyseth Road, Chowpatty, Bombay---400 007

Sarode

- llcaring

Thresholds

! 1/2!

A

--

Audiogram

at K h z - d B

B

--

BERA

E

Present Threshold to Wave V - - Electrocochleogram CMs Absent Sparse

dB 0 1

l'rcscnt Absent

2 0

- Absent

i I

0

AP C

- - (2 N T 45Hz, 55Hz G r a d e s - -

T

- - T o m o g r a m - - (OSS) Ossicles - (CT) Cochlear Turns-(WDW) Window-

180 -- hjdian Journal of Otolaryngology, Volume 43, No. 4, December 1991

i

Present Thresholds 1,2,3,4,5

dB

Normal/Abnormal--

1/0

Normal/Abnormal-Normal/Abnormal--

I/0 I/0

htvestigative Profile o f Patients with a Profound Sensorineural ltearing loss - - Souza et al,

In the prelingual group pure tone thresholds were between 80 - 90 OB in 7 patients, 90 to 100 dB in 111 patients and more than 100 dB in 116 patients. While in the post lingual group the pure tone thresholds were from 90 to 100 OB in 30 patients, I00 to ] 10 dB in 9 patients and 110 to 120 dB in 12 patients. (Table No. IV)

llistory Codes 1000 1010

Congenital Hereditary

--

1020

Familial

--

1030 1040 1050 1060 1070 1080 1090 1100 1110 1120 1130 1140 2000 2010 2020 2030 2040 2050 2060 2070 2080 2090 2100

1011Waardenburg 1012Rctinitis Pigmentosa 1013Heredo-degcnerative (Progressive deafness) 1021Consanguinous 1022Non-Consanguinous

:: : :i iii

Cause unknown Maternal rubella Neonatal jaundice Prematurity Prolonged labour / breach etc. Toxaemia Pregnancy Other infections Drugs T h r e a t e n e d abortions Cerebral Palsy Anoxia Convulsions Acquired Meningitis Mumps D r u g toxicity O t h e r fevers ( G F I ) Post-traumatic Otosclerosis Post--operative Sudden deafness Presbyaeusis Post suppurative

H o r t m a n n ' s Cochlear nerve tester was used to perform the cochlear nerve test where the sensation of sound produced by electrical stimulation of the promontary with small pulse widths from 0.125 ms to 8 ms was determined by a transtympanic needle electrode.

Pure Tone Thresholds ! I

11 patients were from the 2nd decade, 19 patients from the 3rd decade, 8 from the 4th decade and 6 from the 5th decade. Four patients were m o r e than 50 years of age. (Table No. III)

Observation

All the data was analysed and it was found that the deafness was prelingual and perilingual in 234 patients and postlingual in 51 patients. In the prelingual group there were 129 male patients and 105 female patients. Sixty five patients were below the age of 10, 112 patients were from 2nd decade, 49 patients were from 3rd decade and 8 patients were from the 4th decade. In the postlingual group, out of 51 patients 40 were males and 11 were females. 3 patients were less than 10 years of age,

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Age

Age

& Sex

80 - 90

7

190"00 100 110 110 120

111 116

0

30 9 12

--

In 91 patients of prelingual group there was no cause o f deafness detected. In 35 patients hearing loss was due to consanguinity, in 24 patients due to familial causes, in 20 patients following high fever, and prolonged labour and trauma was the cause of deafness in 10 cases. In a few cases the deafness was due to drug toxicity, maternal rubella, neonatal jaundice etc. Out of 51 patients from postlingual group in 10 cases deafness was noted following high fever and in 9 cases due to meningitis. In 5 cases it was due to otosclerosis or bilateral stapedectomy and in another 5 cases in was sudden in onset. In 4 cases it was following infection. The other causes noted were drug toxicity trauma, presbyacusis, mumps, heredodegenerative disorder etc. (Table No.V)

Distribution

Prelingual

Postlingual

65 112 49 8 ------

3 11 19 8 6 2 1 0 1

Male

129

40

Female

105

11

History - Codes 0 11 21 31 41 51 61 71 81

- 10 - 20 - 30 -40 - 50 - 60 - 70 - 80 - 90

tlistory

Prelingual

Congenital Hereditary Wardenburg Retinitis Pigmentosa Heredo-degenerative disordcr , Familial f;onsanguinous Non-consanguinous

1 1 1 0 2 35 22

Postlingual

0 0 0 3 ' 0 0 0 Ii

htdian Journal o f Otolat),~goh~&'v Volume 43, No. 4, l)cccmbcr 1991 -- 181

hwestigative Profile o f Patients with a Profound Sensorineural Hearing loss

History

Prelingual

Cause unknown Maternal rubella Neonatal jaundice Prematurity Prolonged Labour/ breach etc. Toxaemia Pregnancy Other infections Drugs Threatened abortions Cerebral Palsy Anoxia Convulsions Acquired Meningitis Mumps D r u g toxicity O t h e r fevers ( G F I ) Post - traumatic Otosclerosis Post - operative Sudden deafness Presbyacusis Post suppurative

Postlingual

91 6 5 3

1 0 0 0

10 0 2

0 0 0

1 2 1 2

0 0 0 0

4 0 9 20 10 0 0 0 0 0

9 2 4 10 3 5 1 5 3 5

-

-

Souza et aL

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Ecochg Findings SIDE

CM

AP

R L

S S

A A

150

26

R L

P P

A A

28

8

R L

A A

A A

15

7

R L

P S

A A

11

7

R L

S A

A A

9

R L

P A

A A

3

3

P A

A A

3

3

S/P s~

P v

18

R L

,

R L

PRELINGUAL

POSTLINGUAL

-

-

-

-

S : Sparsel P : Present, A : Absent. 7"

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B E R A waves were absent (Fig.l) in 223 prelingual cases, while in 8 patients B E R A waves were present (Fig.2) on both sides with thresholds from 80 to 100 riB, and in 3 patients present only on one side with thresholds ranging from 80 to t00 riB. B E R A waves were absent in all cases of postlingual group, (Table No. VI)

Cz -~I!:+

Bera Findings Waves

Prelingual

Postlingual

Absent

223

51

Present

11

0

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hldian Journal of Otohm.,nt;olo,,an, Volumc 43. No. 4. l ) c c c m b e r 1991

O n E c o c h G , the action potential was absent (Fig.3) in 216 patients of the prelingual group and present (Fig.4) in 18 patients with thresholds from 80 to 100 dB. T h e cochlear microphonics were sparse bilaterally in 150 cases, present bilaterally in 28 cases, absent bilaterally in 15 cases, sparse on one side and present on the other side in 11 cases. In 9 cases the cochler microphonics were unilateral and sparse and in 3 cases unilateral but present. In 18 cases the cochlear microphonics were present, sparse or absent on either side. In the postlingual group on E c o c h G the action potentials

Investigative Profile of Patients with a Profound Sensorineural Hearing loss

-

Souza et al.

-

normal inner ear development (Fig.6) in 108 cases, bilateral cochlear dysplasia in 98 cases (Fig.7) bilateal cochlear and ossicular dysplasia i n 20 cases and unilateral cochlear dysplasia in 4 cases. In

Fig. 5. CN'F Chart the graph was in zone I on the right side and in zone II on the left side. In only one patient the graph was in zone III. (Table No. VIII).

Fig 3 : Ecochg Tracing CM Sparse, AP Absent i~~'m

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the remaining cases there was ossicular dysplasia on one s i d e and cochlear dysplasia on the other side. In the postlingual group t o m o g r a m studies of the

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Fig 6 : Tomogram Cochlea

•

l, Fig 7 : Tomogram Showing Cochlear Dysplasia temporal bones showed normal development in 31 patients, bilateral illdefined cochlea in 12 patients and unilateral illdefined cochlea in 3 patients. In 5 cases there was cochlear otosclercsis. (Table No. IX)

Fig. 4. Ecochg Tracing CM Present, AP Present were absent in all the cases. The cochlear microphonics were sparse bilaterally in 26 cases, present bilaterally in 8 cases, absent in 7 cases and sparse in one side and absent on the other side in 7 cases. T h r e e cases showed the presence of cochlear microphonics on one side. (Table No.VII) In the prelingual g r o u p after cochlear nerve test, in 191 patients the graph was in zone I (Fig.5) in 26 patinets in zone I on the right side and in zone II on the left side and in 8 patients the graph was in zone II. In 2 patients the graph was in zone I, II or III on either side. In a very few patients the graph fell in zone III and IV. In the postlingual group on cochlear nerve testing, the graph fell in zone I in 37 cases, in zone II in 5 cases. In 8 cases

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Cnt Z o n e

Prelingual

I - I

191

I - II

26

Postligual 37 8

I - II/III

2

II - II

8

4

I/II - I/II

2

1

II - Ill

1

III --

qI

1

1

- Ill I---

1

I/II - IV

1

The coronal tomography of the temporal bones in the prelingual group showed

Prelingual G r o u p : (Table No. X) A total n u m b e r of 234 patients from the prelingual group were investigated in detail and we found that there was male predominance and the m a x i m u m n u m b e r of patients were from the second decade, with age ranging from 8 to 40 years. The hearing thresholds by puretone audiometry were found to be more than 90 dB in almost all cases (97 %). F r o m the history in the majoirty of cases (38.8%) there was no cause of deafness detected. In 14.9 % cases the hearing loss

Indian Journal of OtolatyngoloK~' Volume 43, No. 4. December 1991 -- 183

Investigative Profile o f Patients with a Profound Set~sorineural Hearing loss - - Souza et al

Postlingual G r o u p : (Table No. XI) .~ii~ii~iiiii~iii~i~ii~i~iiiii~i~iii~!i~iiiii!i!ii~ii~iiii~iiiiii~iii!!~j~]~iiii~iii~iiii~iii~iiiiiiii~ii~iiiii~ii~iiiiiii~i~ii~!i~i~iii~ii~iiii !~ ~i:~i~ :i:~ ~:i~ ~i~!!ii::::i~i ~!~:ii~!~:i~i!~::ii~:::;i~;::i;~

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Tomogram Findings Development

Prelingual

Bilateral normal Bilateral cochlear dysplasia Bilateral illdefined cochlea Bilateral ossicular and cochlear dysplasia Unilateral cochlear dysplasia Unilateral illdefined cochlea Unilateral ossicular and cochlear dysplasia Bilateral ossicular dysplasia Unilateral ossicular dysplasia Cochlear otosclerosis

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Postlingual

108 98 0 20 4 0 2 1 1 0

31 0 12 0 3 0

5

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Conclusions Prelingual Sex : Age :

: :

Threshold Cause :

: Unknown Consanguinous Familial Non consanguinous O t h e r fevers Bera : Absent Present EcochG : A P absent Present C.N.T. : Zone I Z o n e II Tomogram : Normal Bilateral cochlear & ossicular dysplasia was found to be due to consanguinity while in 10.2 % it was due to familial causes. T h e B E R A showed absence of waves in all except 11 cases (4.7 %) in which thresholds were ranging from 80 to 100 riB. O n E c o c h G only 18 (7.7 %) patients showed presence of action potentials with thresholds ranging from 80 to 100 OB. T h e cochlear microphonics were absent or sparse in most of the cases and present in only 12 % cases. In 81.6 % of patients the cochlear nerve test graph was in zone I. In a few patients (14.5 %) the graph was in zone II. T h e coronal tomography of the temporal bones showed bilateral ossicular and cochlear dysplasia in 50.8 % patients while 46.1% patients showed normal ossicular and cochlear development. In a few cases there was unilateral dysplasia.

Predominantly male 0 ~ 10 11 - - 20 90dB -

27 48 97 38.8 14.9

% % % % %

10.2 % 8% 95.3 % 4.7 % 92.3 % 7.7 % 81.6 % 14.5 % 46.1%

On E c o c h G the action potentials were absent in all cases while the cochlear microphonics were absent in 13.7 %, sparse in 51% and present in 35.29% cases. T h e cochlear nerve test graph was in zone I in 72.5% cases and in zone II in 25.5 % cases. T h e coronal tomography of the temporal bones showed normal d e v e l o p m e n t of.cochlea in 60.78 % cases, unilateral or bilateral illdefined cochlea in 29.42 % cases and cochlear otosclerosis in 9.8 % cases.

Discussion These investigations were performed initially for Cochlear Implant selection where we concluded that an aided audiogram, a cochlear nerve test and a t o m o g r a m were essential for the selection of the candidate and the type of the implant, whereas B E R A & E c o c h G were only of meclicolegal importance to

50.8 % ~;;~;~;:: ~z;~i~i~:.~~ i ~ :::::::::::::::::::::::::::::::::::::::::-

In 51 patients of the postlingual group, the age ranged from 8 - 80 yrs with male predominance. T h e hearing thresholds on p u r e t o n e audiometry were m o r e than 90 OB in all cases. In the majority of patients the hearing loss was noted following high fever (19.6 %) and meningitis (17.6 %). In 9.8 % patients the hearing loss was associated with otosclerosis or bilateral stapedectomy and 9.8% patients had a sudden loss of hearing. All cases showed the absence of B E R A waves.

~ ::: ............. ~ ; ~ i i i : : i l l iT~ie!iXl::: i::i:ii ~!:::::::ii:.:i :::::::::::::::::::::::::::::::::::::::::::::::::::: 1

Conclusions Postlingual Sex : Age :

: :

Threshold

:

Cause

:

Bera : EcochG : C.N.T. Tomogram :

Predominantly male 11-2021 - 30 - 31-40-90 - 100 dB - 100 dB - -

Other fevers : Meningitis Otosclerosis Sudden deafness Absent P/esent A. P. absent Zone I Z o n e II Normal Illdefined cochlea Cochlear otosclei'osis

184 -- h~dian Journal o f Otola~,ngolo&,v Volume 43, No. 4. December 1991

21.5 % 37.2 % 15.6 % 58.8 % 41.1% 19.6 % 17.6 % 9.8 % 9.8 % 100 % 0 % 100 % 72.5 % 2.5.5 % 60.78 % 29.42 % 9.8 %

Investigative Profile of Patients with a Profound Sensorineural lfearing loss - - Souza et aZ establish objectively the patients level o f hearing. H o w e v e r , b e c a u s e o f the large series we could t h r o w a t r e m e n d o u s a m o u n t o f light o n t h e aetiology, age and sex incidence, site a n d pathology o f the lesion causing bilateral sensorineural hearing loss. F r o m the survey in the prelingual group, we found that t h e c a u s e o f deafness could not be identified f r o m the history in the majority o f patients. W h e r e t h e r e was a positive history, the cause was mostly consangiuinous o r familial. T h e hearing loss was generally bilateral p r o f o u n d rather than a total hearing loss, B E R A and E c o c h G , however, s h o w e d that in all cases the lesion was in the cochlea. N o case o f d e a f n e s s d u e to a brain stem or central lesion was d e t e c t e d , as the group analysed w e r e all cases o f long standing bilateral p r o f o u n d sensorineural loss without any o t h e r neurological defects and aphasic patients w e r e not included. T h e t o m o g r a m s h o w e d the majority o f patient having a cochlear dysplasia. However, in a large n u m b e r o f cases the cochlear d e v e l o p m e n t was normal and these patient w e r e perilingual w h e r e the deafness m u s t h a v e o c c u r e d just after the birth o r b e f o r e t h e d e v e l o p m e n t o f the speech. In the postlingual g r o u p the most c o m m o n cause o f d e a f n e s s was high fever. The next c o m m o n c a u s e was meningitis and only in 10 % was t h e r e a s u d d e n loss o f hearing. In 10 % cases t h e r e was history o f otosclerosis o r bilateral stapedectomy. In almost all t h e cases the deafness was total. T h e B E R A a n d E c o c h G again showed all the lesions to be in the cochlea. The t o m o g r a m in the majority o f the cases showed normal d e v e l o p m e n t o f the cochlea. H o w e v e r , in the otosclerotic patients t o m o g r a m s h o w e d cochlear otosclerosis and in t h e remaining cases the

cochlea was illdefined and this p h e n o m e n o n in postlinguals can be attributed to prolonged disuse and obliteration o f t h e scala tympani.

11. Hyde M.L.(1985 b) : The effect of cochlear lesions on the ABR. In the auditory brain stem response, edited by J.T.Jaeobson pla 133 - 146. San Diego : College 1till Press.

References

12. Jerger J.,Mauldin L.(1978) : Prediction of SN hearing level from the brain stem evoked responses. Archieves of Otolao'ngology 104 : 456 - 461.

1. Banfai K.P., Hortmann G., Karizag A., Kubik S., Luers P (1982) : Selection of patients. Acta Otolaryngol (Stockh) 1989 Suppl. 411 : 147 - 156 2. British Society of Audiology (1981) : Recommendations for pure tone audiometry. British Journal of Audiology 15 : 213 - 216 3. Davis II (1976) : Principles of Elcctric Response Audiometry. Annals of Otology Rhh+ologv & Laryngology 85 (suppl.-28):l - 96. 4. Davis II (1981): Electric Response Audiology : Past, present and future. Ear and Hearing 2 : 5-8. 5. Davis H., Ovcen J.(1985): Auditory Evoked Potentials In evoked potential testing, clinical applications. Edited by J. H. Own, H. Davis pp 55 - 108, Orlando : Grune & Stratton. 6. Eggermont J.J., Odenthal D.W., Schmidt P.H., Spoor A. (1974) : Electrocochleography : basic principles and clinical application. Acto Otolaryngolo~ca Suppl. 316. 7. Erber N., Alencewicz C. (1976): Audiological evaluation of deaf children. Journal of Speech attd Hearing disorders 4I : 256 - 267. 8. Hannley M.(1986) : Basic principles of auditory assessment. London. 9. Hecox K., Galambos R. (1974) : Brain stem auditory evoked responses in human infants and adults. Archieves of Otolaryngology 99 : 30 - 33. 10. Hyde M.L.,Blair R.L.(1981) : The auditory brain stem responses in neuro-otology, perspectives and problems. Journal of Otolaryngology 10 : 117 - 125.

13. Karger S. Cochlear implants in clinical use. Advances in Audiology Vol .II. 14. Newton U.(1985) Aetiology of bilateral SN heating loss in young children.

Journal of Laiyngology and Otolo~ Suppl. 10. 15. Picton T.W., Stapells D.R., Campbell K.B.(1981) : Auditory evoked potentials from the human cochlea and brain stem. Journal of Otolaryngolog~, 10 (suppl 9) : 1 - 41. 16. Ruben R.J.(1967) : Cochlear Potentials as a diagnostic test in deafness. In sensorineural heating process and disorders, edited by A.B. Graham pp 313 - 337. Boston. Little, Brown. 17. Schindler R.A., Kessler D.K.(1985) : Selection of patients for an experimental multi-channel implant programme. In Schindler R.A., Merzenich M.M. (EDS) : Cochlear implants. New York : Raven Press pp 407 - 410. 18. Simmons F.B., Lusted It.S., Myers T. (1985) Selection Otiteria for implant candidates. In R.A. Schindler & M.M. Me~enich (EDS) Ravan Press, New York pp 383 - 385. 19. Turner R.G., Nielsen D.W.(1984) : Application of clinical decisions analysis to audiological test. Ear andHearing 5 : 19_5- 133. 20. Turner R.G., Shepard N.T., Frazer G.L.(1984) : Clinical performance of audiological and related diagnostic tests. Ear and ltearing 5 : 187 - 194. 21. Turner ILG., Frazer G.L., Shepard N.T.(1985): Formulating and evaluating audiological test protocols. Ear and tlearing 5 : 321 - 330.

Indian Journal of Otola~.ngolog~; Volume 43, No. 4, December 19c~1 - 185