[email protected] (1).pdf

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1/5

ABR

thresholds

in

infants born

with

CLP

and

OME

and

infants

with

OME

H. Sundman a, T. Flynn b,*, B. Tengrotha, A. Lohmander b

aHearing and Balance Clinic, Karolinska University Hospital, Stockholm, SwedenbDivision of Speech and Language Pathology, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden

1. Introduction

Children born with cleft palate and/or lip (CP L) present with a

higher

prevalence

of

otitis

media

with

effusion

(OME)

than

children

born without CP L. Prevalence of OME has been reported to range

from 76 and 97 percent in children with CP L between the ages of

two and 24 months [1–11]. This high prevalence of OME is most likely

due

to

Eustachian

tube

dysfunction.

The

tensor

veli

palatini

and

the

levator veli palatini muscles are not able to contract properly and

open the Eustachian tube [1,12,13]. Therefore, the Eustachian tube is

unable to equalize pressure and leads to negative pressure in the

middle

ear.

This

negative

pressure

results

in

a

retracted

tympanic

membrane

and

secretion

of

mucous

from

the

tissues

through

osmosis

into the middle ear cavity [2,7].

OME is associated with a mild to moderate, fluctuating

conductive

hearing

impairment

across

the

speech

frequencies

[14].

A

few

studies

have

investigated

this

association

in

young

children [15–17]. Gravel and Wallace [15] demonstrated infants at

one year of age with an average of four episodes of bilateral OME

presented

with

elevated

thresholds

(37.8

dB

nHL)

as

compared

to

a

group of infants (20.3 dB nHL) with an average of less than one

episode. Other studies have investigated OME and the associated

hearing loss in relation to universal newborn hearing screening

(UNHS).

Aithal

and

colleagues

[17]

demonstrated

68

percent

of

newborns (average of 47.5 days), which had OME also had a

hearing loss. For those infants who presented with OME and a

hearing loss, an average threshold of 50 dBnHL was recorded when

the

infant

was

49

days

old

[16]. Second,

Boudewyns

and

colleagues

[16] demonstrated 55 percent of the newborns (average 49 days)

who failed screening had a hearing loss associated with OME

ranging between 40 and 60 dBnHL in both ears. These infants were

followed

longitudinally

and

presented

with

normal

hearing

by

4.8

months

of

age.

Five

of

the

64

infants

presented

with

a

CP L.

Furthermore, there have been several studies focusing on OME

and an associated hearing loss in children with CP L. Four studies

have

reported

young

children

with

CP L exhibit a higher prevalence

of

hearing

impairment

than

children

without

CP L. Broen et al. [2]

demonstrated young children with CP L were more likely to fail a

hearing screening between 9 and 30 months of age. The other three

studies

reported

a

range

between

55

and

93

percent

of

ears

of

infants

and

young

children

with

CP L and OME to demonstrate a mild to

moderate hearing loss [9,10,18]. On the contrary, Jocelyn et al. [6]

reported fewer children with CP L (25 percent) which exhibited

mild

to

moderate

hearing

impairment

at

12

and

24

months

of

age

as

International Journal of Pediatric Otorhinolaryngology 81 (2016) 21–25

A R T I C L E I N F O

Article history:Received 30 August 2015

Received in revised form 2 November 2015

Accepted 30 November 2015

Available online 12 December 2015

Keywords:

Auditory brain stem response

Cleft palate

Hearing loss

Otitis media with effusion

A B S T R A C T

Objectives:

The aim of this study was to investigate and compare auditory brainstem response (ABR)thresholds related to otitismediawith effusion (OME) in infants with andwithoutcleft palateand/or lip

(CP L).

Methods: Forty-seven infants with CP L

and 67

infants

with

OME

participated

in the

study.

Hearing

thresholds

of

ears

of

infants

with

OME

were

compared

between

groups

andwithin

the

group

with

CP

L.

Results: Infants with CP L and OME presented with similar hearing thresholds as infants with OME and

not

CP L. Within the cleft group, infants with isolated cleft palate and OME demonstrated significantly

higher hearing thresholds than infants with unilateral cleft lip and palate and OME.

Conclusion: A high prevalence of infantswith CP L

present

with

OME

early

in

life.

Hearing

thresholds

of

these infants are similar to infants without CP L, but with OME. The ear status and hearing thresholds of

infants

with

CP L needs to be monitored to be able to provide the best access to hearing in order to fully

allow

speech

and

language

development.

2015

Elsevier Ireland Ltd. All rights reserved.

* Corresponding author.

E-mail address: [email protected] (T. Flynn).

Contents

lists

available

at

ScienceDirect

International Journal of Pediatric Otorhinolaryngology

jo urn al hom ep ag e: www.els evier . c om/locat e/ i jp o r l

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0165-5876/ 2015 Elsevier Ireland Ltd. All rights reserved.

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2/5

compared to zero and six percent in the children without CP L. This

lower

percentage

of

children

with

hearing

impairment

may

be

due

to

the significantly higher number of children with ventilation tubes in

the group of children with CP L [6].

This contradicting evidence is also seen in the hearing screening

of

newborns

with

CP L. Three studies reported a range of 12 and

28

percent

of

newborns

with

CP L which failed their newborn

hearing screen [19–21]. On the contrary, four other studies described

a higher percentage of hearing impairment, between 70 and

84

percent,

in

newborns

with

CP L with a mild to moderate

conductive

hearing

loss

[10,22–24]. This

discrepancy

may

be

to

audiometry methodology. Newborn hearing screening was con-

ducted either with otoacoustic emission (OAEs) or automated

auditory

brainstem

response

(AABR)

[19–21].

These

methods,

which

utilized

a

pass/fail

criteria,

were

used

in

the

studies

reporting

a

lower

incidence of abnormal hearing. The other studies obtained a threshold

of hearing via an auditory brainstem response (ABR) [10,22,23]. De-

termining

a

threshold

is

a

more

detailed

definition

of

hearing

sensitivity

and

includes

newborns

with

mild

hearing

loss,

which

may

have been missed via screening or pass/fail methods. Another factor

which may have contributed to the discrepancy is age of the newborn.

In

the

studies

with

a

lower

rate

of

abnormal

hearing,

the

infants

were

screened

at

birth;

while

the

studies

with

a

higher

rate

of

abnormal

hearing, the infants were tested when they were older, rangingbetween an average of 43 days up to 14 months of age.

Furthermore,

these

studies

do

not

compare

the

hearing

in

newborns

with

CP L to newborns without CP L, but with OME.

Children with CP L and OME have been shown to present with

higher thresholds than children without CP L, but with OME

[7].

Flynn

et

al.

[7]

demonstrated

children

with

unilateral

cleft

lip

and

palate

(UCLP)

with

OME

and

a

hearing

impairment

exhibited

significantly higher hearing thresholds than children without UCLP,

but with OME and a hearing impairment [7]. Therefore, it is critical to

investigate

when

this

significant

difference

may

occur

as

this

is

a

sensitive period for the development of auditory, speech, and

language skills.

There

is

insufficient

data

to

conclude

the

timing

and

possible

long-term benefits of the placement of ventilation tubes [25]. TheNICE guidelines specify, ventilation tubes should only be placed at

palatal closure after careful otological and audiological assess-

ment,

not

prophylactically

[26].

However,

Klockars

and

Rautio

[11]

demonstrated

the

majority

of

infants

with

ventilation

tubes

placed

at four months of age during time of soft palate repair resulted in a

lower prevalence of OME at 12 months of age as compared to

infants

who

received

ventilation

tubes

at

four

months

of

age

but

with

soft

palate

repair

at

12

months

of

age

[11].

It

was

hypothesized that the earlier repair of the soft palate aided the

Eustachian tube to function effectively and allow the ventilation

tubes

to

not

become

occluded.

Ventilation

tubes

were

placed

either

following

the

diagnosis

of

OME

by

otomicroscopy

or

paracentesis during surgery or prophylactically. Hearing levels

were

not

reported.As

it

is

controversial

when

to

place

ventilation

tubes,

it

is

crucial

to

define

the

possible

prevalence

of

an

associated

hearing

impairment in newborns with and without CP L. This may lead

to changes in protocol for the placement of ventilation tubes.

Therefore,

the

aim

of

this

study

was

to

investigate

and

compare

auditory

brainstem

response

(ABR)

thresholds

related

to

otitis

media

with effusion (OME) in infants with and without CP L.

2.

Materials

and

methods

2.1. Materials

The

study

was

a

retrospective

chart

review

at

a

single

hospital

(Karolinska

University

Hospital,

Sweden).

Medical

files

between

January 2011 and January 2013 were reviewed for two groups of

possible

participants.

The

two

groups

included

infants

with

CP L

(cleft group) and infants without cleft, but with OME (non-cleft

group). For the non-cleft group, all infants with a medical record

containing a diagnosis of OME and ABR threshold levels were

included

in

the

study.

Infants

in

the

non-cleft

groups

were

excluded

if

they

had

a

medical

diagnosis

or

syndrome,

a

malformation,

or

a

hearing impairment not caused by OME. Infants in the cleft group

were excluded if they had an additional medical diagnosis or

malformation,

a

syndrome,

or

a

sensori-neural

hearing

impairment.

The

first

group

(non-cleft

group)

included

infants

who

failed

the

newborn hearing screening and were diagnosed with OME. Sixty-

six infants (41 males and 25 females) with a mean age of 97 days

(range:

37–197

days)

were

diagnosed

with

either

unilateral

or

bilateral

OME.

The

second

group

(cleft

group)

consisted

of

50 infants (32 males and 14 females) with a mean age of 65 days

(range: 25–145 days). Twenty-six infants presented with an

isolated

cleft

of

the

palate

(ICP),

14

infants

with

unilateral

cleft

lip

and

palate

(UCLP),

and

ten

infants

with

bilateral

cleft

lip

and

palate

(BCLP).

2.2.

Methods

Data were collected from the medical records at the time of thediagnostic ABR during clinical routine visits between January

2011

and

January

2013.

Hearing

thresholds

from

the

ABR

and

otomicroscopy

examination

were

collected.

2.2.1. Hearing sensitivity

The

click

evoked

ABR

was

obtained

while

infants

were

sleeping

using

the

Interacoustics

EP25

(Denmark).

The

click

evoked

ABR

was utilized as it is clinical protocol at the Karolinska University

Hospital following a failed OAE screen. Rarefaction pulses were

delivered

at

a

rate

of

39.1

stimuli/second

through

ER-3A

ABR

insert

earphones. The recording window was 15 ms. Initial stimuli were

presented at 50 dBnHL. Stimuli intensity was increased or

decreased

in

10

dB

increments

and

5

dB

increments

when

necessary. Thresholds were tracked using wave V. A minimumof 1700 sweeps for each waveform were obtained. Twenty dBnHL

was the lowest stimuli presented and 90 dBnHL was the maximum

level

presented.

Threshold

was

determined

when

two

recordings

were

repeated.

The click evoked ABR was performed during natural sleep on

both ears of the infant. If the infant woke during the measurement,

any

further

collection

of

data

was

discontinued

until

the

infant

went

back

to

sleep.

Fourteen

infants

in

this

study

underwent

two

ABR assessments. The second ABR was performed due to an

incomplete assessment due to lack of sleep or restlessness. The

lowest

estimated

threshold

obtained

was

used

during

the

analysis.

2.2.2. Ear status

A

pediatric

otolaryngologist

performed

otomicroscopy

on

theday

of

ABR

testing

to

determine

ear

status.

Results

were

classified

as

normal

or

abnormal

(fluid

filled

middle

ear

cavity

or

retracted

tympanic membrane).

2.3.

Statistical

description

and

analysis

Statistical analysis of the results was performed using the t -test

to compare the mean hearing thresholds between the cleft and

non-cleft

groups

and

the

ANOVA

to

compare

cleft

types

within

the

cleft

group.

Effect

size

was

analyzed

with

Cohen’s

d.

The

data

were

analyzed using SPSS for Windows (Version 22).

Data collection and analyses were carried out according to

ethical

principles

for

medical

research

involving

human

subjects

and

with

permission

from

the

Head

of

the

Clinical

Department

of

H. Sundman et al. / International Journal of Pediatric Otorhinolaryngology 81 (2016) 21–2522


3/5

Hearing and Balance at Karolinska University Hospital, Solna,

Stockholm, Sweden (Swedish Ethical Law 2003:460).

3. Results

The

data

analysis

focused

on

the

individual

ears

of

the

participating

infants.

There

are

a

total

of

116

infants

providing

232 ears for examination in the cleft and non-cleft groups. Within

the cleft group, there were 100 ears. Of those 100 ears, 88 presented

with

OME

on

the

day

of

testing.

Twelve

ears

were

excluded

from

the

study

including

four

children

with

no

OME

bilaterally

(one

infant with BCLP and three infants with ICP). Therefore, data from

88 ears with OME was gathered for further analysis (Table 1). In thenon-cleft

group,

66

infants

providing

132

potential

ears

were

studied.

Of

the

132

possible

ears,

105

presented

with

OME

on

the

day of testing and were designated for further analysis. In total,

193 ears from infants with OME in the cleft (n = 88) and non-cleft

group

(n

=

105)

were

included.

The

data

were

analyzed

and

compared

between

the

cleft

group

and

non-cleft

group

and

within

the cleft group by type of cleft.

The non-cleft group exhibited a mean threshold of 41.4 dBnHL

(SD:

8.8)

and

the

cleft

group

exhibited

a

mean

threshold

of

40.1

dBnHL

(SD:

9.5)

(see

Fig.

1).

There

was

no

significant

difference between the cleft and non-cleft groups on hearing

sensitivity (F (1, 190) = 0.047, p = 0.829).

Within the cleft group, the mean ABR threshold value for infants

with UCLP was 37.5 dBnHL (SD: 7.9; range: 20–50), 44.2 dBnHL

(SD: 8.9; range: 30–60) for infants with ICP and 40.3 dBnHL (SD: 7.6;

range: 30–55) for infants with BCLP (see Fig. 2). There was a

significant difference within the cleft group when the group was

divided by cleft type (F (1, 84) = 5.44, p = 0.006). A significant

difference was present between the UCLP and ICP groups, with

infants with ICP presenting with worse hearing thresholds ( p = 0.005)

(see Table 2). This significant difference had a large effect size

(d = 0.796).

4. Discussion

Eight-eight

percent

of

infants

with

CP L presented with OME.

These

infants

did

not

demonstrate

significantly

worse

hearing

thresholds as compared to infants with OME. However, the infants

with ICP, exhibited significantly higher thresholds than the infants

with

UCLP.

This

has

not

been

previously

reported

in

the

literature.

The

prevalence

of

OME

in

the

cleft

group

(88

percent)

is

in

the

higher range of the previously reported prevalence of between

18 and 94 percent. However, when examining the literature, there

are

two

groups

of

results:

18

to

28

percent

and

65

to

94

percent.

This

study

has

similar

results

to

other

studies

stating

a

prevalence

of OME ranging from 65 to 94 [10,11,23,24]. In contrast, the

present results are considerably higher than the 18 to 28 percent

Table 1

Number of infants and ears with OME included in the data analysis.

Non-cleft group Cleft group

UCLP ICP BCLP

Infants Ears Infants Ears Infants Ears Infants Ears

Bilateral OME 39 (59%) 78 (74%) 12 (86%) 24 (92%) 22 (96%) 44 (98%) 8 (89%) 16 (94%)

Unilateral OME 27 (41%) 27 (26%) 2 (14%) 2 (8%) 1 (4%) 1 (2%) 1 (11%) 1 (6%)

Total number of infants and ears 66 105 14 26 23 45 9 17

Table

1

Number

of

infants

and

ears

included

in

the

data

analysis

by

group.

Unilateral

Cleft

Lip

and

Palate

(UCLP),

Isolated

Cleft

Palate

(ICP),

Bilateral

Cleft

Lip

and

Palate

(BCLP).

Fig. 1. Box plots showing maximum, median, and minimum hearing thresholds in dB nHL and first and third quartile for all ears in the cleft and non-cleft groups with otitis

media with effusion (OME).

H. Sundman et al. / International Journal of Pediatric Otorhinolaryngology 81 (2016) 21–25 23


4/5

reported when examining hearing screening results in infants with

CP L [19–21]. This discrepancy in prevalence may be due to

methodological

differences

and

aims

of

the

studies.

The

studies

reporting a lower prevalence were investigating hearing in infants

with CP L with a focus on the hearing screening results or

thresholds.

However,

OME

is

not

always

associated

with

a

hearing

loss

or

a

fail

on

a

hearing

screen.

Andrews

and

colleagues

[10]

illustrated the hearing thresholds and tympanometry results in theirstudy. Fifteen percent of ears (10/67) exhibited flat tympanometry

and

mean

hearing

levels,

which

passed

screening

(range:

25–

35

dBnHL).

In

the

present

study,

30

percent

of

ears

with

OME

exhibited mean hearing levels, which passed screening (range: 20–

35

dBnHL).

The

noted

difference

between

15

and

30

percent

may

be

due

to

methodological

methods

of

defining

OME.

Andrews

and

colleagues [10] utilized high-frequency tympanometry (flat tympa-

nograms) to indicate the presence of OME while the present study

defined

the

presence

of

OME

by

visualization

of

the

tympanic

membrane

by

an

experienced

otolaryngologist

who

performed

otomicroscopy. OME may be present with other types of tympano-

metry [27]. The inclusion of infants with syndromes does not explain

the

discrepancy,

as

studies

reporting

lower

and

higher

prevalence

of

OME

included

infants

with

syndromes

[10,19,21].In the present study, there was no significant difference in

hearing thresholds between infants with CP L and infants without

CP L. One study has reported hearing thresholds of infants with a

conductive

hearing

loss

due

to

OME

[16].

In

this

study,

an

average

hearing threshold of 50 dBnHL was reported in infants without

CP L, but with OME; while the present study demonstrated average

hearing

thresholds

of

41.4

dBnHL

and

the

cleft

group

and

40.1

dBnHL

in the non-cleft group. The differences in thresholds may be due to

inclusion criteria. In the Boudewyns et al. [16] study, 25 percent of the

infants

presented

with

a

known

risk

factor

for

hearing

loss

(6

of

them

with

craniofacial

anomalies)

while

infants

with

additional

malforma-

tions or sensorineural hearing loss were excluded in the presentstudy. Infants with CP L in the present study presented with similar

hearing

thresholds

of

infants

with

CP L in a previously reported

study

[22].

In

the

present

study,

the

infants

with

CP L exhibited an

average threshold of 41.4 dBnHL while infants in the Viswanathan

et

al.

[22]

study

presented

with

40

dBnHL

right

ear

and

39.7

dBnHL

for

left

ear.

On

the

contrary,

Andrews

and

colleagues

[10]

presented

higher thresholds for infants with CP L with thresholds of 53 dBnHL

in the left ear and 49 dBnHL in the right ear. This difference may be

due

to

the

inclusion

criteria.

The

infants

in

the

present

study

did

not

present

with

additional

malformations

and/or

syndromes

and

22 percent of the infants in the Viswanathan et al. [22] study

presented with syndromes; while 30 percent of the infants included

in

the

Andrews

et

al.

[10]

study

presented

with

syndromes.

The

elevated

thresholds

in infants

with

ICP

and

OME

in

thepresent study does not follow previous literature on hearing

thresholds in individuals with CP L. There is no other study that

compares

the hearing

thresholds

of

infants

with

different

cleft types.

However,

there

are

two

studies

which

report

typeof

cleft

in

relation to

the degree of hearing impairment [22] and hearing screening results

[20]. Both studies present similar results with infants with ICP and UCLP

presenting

withworse

hearing

than

those

with

BCLP.

Infants

with ICP

and

UCLP

exhibited

a

higher

prevalence

of

moderate

to

severe

hearing

impairment (12 and 10 percent) or failure on hearing screening

(13 percent) than infants with BCLP (5 percent). A larger difference

between

the

ICP

and

UCLP

group

may

have

been

seen

if

Viswanathan

and

colleagues [22]

and

Szabo

and

colleagues

[20]

had

compared

hearing thresholds instead of categories of hearing impairment or

failure

of

hearing

screening.

Both

studies

did

not

mention

ear status.

Fig. 2. Box plots showing maximum, median, and minimum hearing thresholds in dB nHL and first and third quartile for all ears in the cleft group with otitis media with

effusion (OME). Cleft types include: Unilateral Cleft Lip and Palate (UCLP), Isolated Cleft Palate (ICP), Bilateral Cleft Lip and Palate (BCLP).

Table 2

Comparison of hearing sensitivity within the cleft group.

Cleft groups Mean difference Standard error P value

ICP-UCLP 6.71 2.07 0.005

ICP-BCLP 3.91 2.39 0.236

BCLP-UCLP 2.79 2.61 0.535

Results from Post-doc Tukey test comparing hearing sensitivity between cleft

groups: Unilateral Cleft Lip and Palate (UCLP), Isolated Cleft Palate (ICP), Bilateral

Cleft Lip and Palate (BCLP).

H. Sundman et al. / International Journal of Pediatric Otorhinolaryngology 81 (2016) 21–2524


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