Identification of Hearing Loss in Pediatric Patients With Down Syndrome

Original ResearchPediatric Otolaryngology

Identification of Hearing Loss in PediatricPatients with Down Syndrome

OtolaryngologyHead and Neck Surgery146(1) 135140 American Academy ofOtolaryngologyHead and NeckSurgery Foundation 2012Reprints and permission:sagepub.com/journalsPermissions.navDOI: 10.1177/0194599811425156http://otojournal.org

Albert H. Park, MD1, Matt A. Wilson, MD1, Paul T. Stevens2,Richard Harward, AuD3, and Nancy Hohler, AuD4

No sponsorships or competing interests have been disclosed for this article.

Abstract

Objective. To determine the type of hearing loss, incidence ofthe lost to follow-up rate, and the time to diagnose sensori-neural hearing loss (SNHL) in children with Down syn-drome (DS) identified from a statewide database.

Study Design. Case series with chart review.

Setting. Pediatric referral center.

Subjects and Methods. Three hundred forty-four patientswith DS born in Utah between January 2002 and December2006 were identified using the Utah Department of HealthsNewborn Hearing Screening database and birth defectsregistry.

Results. Three hundred thirty-two patients were included inthe study. Eighty-seven infants (26.2%) did not pass theirnewborn hearing screening (NBS). Thirty-three of thesechildren (37.9%) had a conductive hearing loss attributed toserous otitis media. Five infants had SNHL; 3 children werediagnosed with a mixed hearing loss (MHL). The averagetime to diagnose a sensorineural hearing loss was 485 6601 days. One child who passed his NBS was subsequentlyfound to have an SNHL. More than 43% of the newbornswith DS who passed their NBS developed a conductivehearing loss requiring insertion of ventilation tubes. Eighty-four percent of newborns with DS who did not undergoNBS did not have any apparent subsequent audiologictesting.

Conclusion. Patients with DS present with a relatively highincidence of conductive hearing loss, MHL, and SNHL and ahigher lost to follow-up rate compared to patients withoutDS. The authors were not able to diagnose SNHL withinthe 90-day period recommended by the Joint Committeeon Infant Hearing.

Keywords

newborn hearing screening, Down syndrome, sensorineuralhearing loss

Received September 20, 2010; revised August 25, 2011; accepted

September 9, 2011.

Down syndrome (DS) is estimated to occur in 1 in

700 to 1 in 1000 live births, making it one of the

most common genetic syndromes.1 Common mani-

festations of this syndrome include external ear canal steno-

sis, chronic ear disease, and hearing loss, conditions many

otolaryngologists, audiologists, and primary care physicians

regularly face.2 Stenotic ear canals occur in up to 50% of

newborns with DS, making the diagnosis of otitis media

with effusion challenging.3 Several studies have cited the

increased incidence of chronic ear disease in this popula-

tion.3,4 Estimates of hearing loss range from 38% to 78% of

all DS patients.5-9

Much of this information had been presented before the

advent of universal newborn hearing screening. Because

many of these cited articles reporting the relatively high

incidence of conductive and sensorineural hearing loss

(SNHL) have been in the literature for several decades, it

would be informative to determine whether universal new-

born screening programs have been successful in diagnosing

these patients expeditiously. The purpose of this study is to

determine whether a statewide newborn screening program

provides identification of sensorineural hearing loss by 3

months of age, the distribution of hearing loss type in this

program, and the lost to follow-up rate. We hypothesize that

the time to diagnosis of DS infants with sensorineural hear-

ing loss will not be within the guidelines mandated by the

Joint Committee on Infant Hearing (JCIH) and that the inci-

dence of conductive hearing loss, SNHL, mixed hearing

loss, and indeterminant loss, as well as the lost to follow-up

rate, is high.10

1Division of OtolaryngologyHead and Neck Surgery, University of Utah,

Salt Lake City, Utah, USA2University of Utah School of Medicine, Salt Lake City, Utah, USA3Utah Department of Health, Salt Lake City, Utah, USA4Audiology, Primary Childrens Medical Center, Salt Lake City, Utah, USA

This article was presented at the 2010 AAO-HNSF Annual Meeting & OTO

EXPO; September 26-29, 2010; Boston, Massachusetts.

Corresponding Author:

Albert H. Park, MD, Division of OtolaryngologyHead and Neck Surgery,

University of Utah, 50 North Medical Drive, 3C 120, Salt Lake City, UT

84132, USA

Email: [email protected]

at IMSS on May 26, 2015oto.sagepub.comDownloaded from

Methods

Subjects

Three hundred forty-four newborns with DS born in Utah

between 2002 and 2006 were identified using the Utah Birth

Defects Registry. Several outcome measures were determined

using the Utah Department of Health Hi*Track informationmanagement system and the Intermountain Healthcare (IHC)

electronic medical record system. The Utah Newborn

Hearing Screening Program has been considered a very suc-

cessful initiative, with more than 97% of the 53,080 new-

borns delivered being screened for 2010 with an overall

initial state pass rate of 95.8%. The Utah Department of

Health is responsible for data collection and management,

follow-up, and technical assistance for the state screening

program. It helped establish several audiological diagnostic

sites throughout the state that can provide complete diagnos-

tic services to newborns and infants. The IHC is the largest

health care provider in the Intermountain West. More than 20

hospitals, including the only childrens hospital in Utah,

Primary Childrens Medical Center, are owned by the IHC. It

provides insurance to 19% of all Utah residents.

Outcome measures included newborn hearing screening

results, otoscopic examinations, behavioral audiometry, tym-

panometry/immitance, otoacoustic emissions, auditory brain-

stem response (ABR) testing thresholds, magnetic resonance

and computed tomography temporal bone imaging, time to

diagnosis of hearing loss, time to hearing loss treatment, and

surgical treatment. Institutional review board (IRB) approval

was obtained from the Utah Department of Health,

University of Utah, and Primary Childrens Medical Center.

The measures of hearing were categorized as normal hear-

ing, conductive hearing loss, sensorineural hearing loss,

mixed hearing loss, indeterminant hearing result, and lost to

follow-up. Normal hearing results included behavioral thresh-

olds at 500, 1000, 2000, and 4000 Hz better than 20 dB or

ABR thresholds better than 30 dB. Conductive hearing loss

was confirmed with the presence of an air-bone (AB) gap

greater than 10 dB based on ABR or behavior testing.

Sensorineural hearing loss was defined as a greater than a

20-dB threshold on behavioral testing at 500, 1000, 2000,

and 4000 Hz or greater than 30-dB thresholds on ABR click

and/or tone burst thresholds with no AB gap present. Mixed

hearing loss included a combination of sensorineural and con-

ductive hearing loss. Indeterminant hearing loss included sub-

jects whose hearing loss type was not determined (eg, lack of

bone conduction testing). Lost to follow-up patients were

those whose audiologic and otoscopic testing could not be

found in the medical records (or in the Hi*Track database).

ResultsNewborn Hearing Screening Data for DS and Non-DSNewborns in Utah

Of 258,289 children born in the state of Utah between 2002

and 2006, 344 (0.13%) had Down syndrome, including 199

(57.8%) males and 146 females (42.2%). Twelve (3.5%)

died during the newborn period, and no additional data were

collected on these subjects. Three hundred thirty-two chil-

dren had otoscopic and audiologic data available for analy-

sis. Two hundred thirty-two newborns (69.9%) with DS

passed their newborn hearing screening (NBS; Figure 1).This percentage is lower than the 92.8% of all infants

(234,545) who passed during this period. Eighty-seven

(26%) failed their screening, and 13 (3.9%) did not undergo

screening. The percentage of all infants not screened was

less than the DS group at 1.8% (4741 infants).

Distribution of Hearing Loss in the DS Newborns WhoDid Not Pass Their NBS

Of the 87 (26.2%) newborns with DS who did not pass their

NBS, 16 newborns with DS (18.4%) were subsequently

Newborns with DSAlive

n = 332

DS Failed NBSn = 87

DS Passed NBSn = 232

DS No NBSn = 13

Normal Hearingn = 16

(18.4%)

Conductive HLn = 33

(37.9%)

Sensorineural HLn = 5

(5.7%)

Mixed HLn = 3

(3.4%)

Indeterminantn = 8

(9.2%)

No Follow-upn = 22 (25.3%)

Figure 1. Distribution of normal and hearing loss in the Down syndrome (DS) population. HL, hearing loss; NBS, newborn hearingscreening.

136 OtolaryngologyHead and Neck Surgery 146(1)


found to have normal hearing (Figure 1). Thirty-three(37.9%) newborns with DS were diagnosed with a conduc-

tive hearing loss. Twenty-five of these infants had normal

hearing following insertion of ventilation ear tubes. Seven

infants had a persistent conductive hearing loss following

ear tube insertion and following resolution of otorrhea or

middle ear effusion. Audiologic testing for 1 infant was

inconclusive following tube insertion.

Five infants (5.7%) with DS were diagnosed with sensori-

neural hearing loss. The distribution of hearing loss ranged

from moderate to profound. Three of the 5 infants had unilat-

eral loss. The time from screening to diagnosis of a hearing

loss was 485 6 601 days (range, 16-1185 days). Three of the5 infants were diagnosed within 3 months of birth. One child

diagnosed 1185 days after birth had a complicated medical his-

tory, including DiGeorge syndrome, Robertsonian translocation,

antiphospholipid syndrome, encephalopathy, stroke, seizure dis-

order, aspiration, and ventilator dependence. Presumably, the

childs numerous hospitalizations and surgical procedures

delayed the diagnosis and treatment of his sensorineural hearing

loss. The other child diagnosed with hearing loss more than 3

months after birth required repair of an esophageal atresia.

During his hospitalization in the neonatal intensive care unit, he

underwent otoacoustic emission (OAE) and ABR testing at 16

days of life. The audiologist documented a concern for a right

moderate to severe hearing loss. The child unfortunately was

not seen for subsequent testing for another 3 years.

Three infants (3.4%) with DS were diagnosed with a

mixed hearing loss. Time from screening to a diagnosis of a

mixed hearing loss was 60 6 77 days. One child was diag-nosed later than 90 days. This child had an unbalanced

atrioventricular (AV) canal requiring a pulmonary artery

banding followed by a Fontan procedure. The complex

congenital heart problems may have delayed a timely diag-

nosis for this infant. Eight children (9.2%) had an indetermi-

nant diagnosis. Twenty-two children (25.3%) were lost to

follow-up. Community otolaryngologists treated some of

these infants, and their audiograms could not be found in

the IHC electronic medical record system.

Distribution of Hearing Loss in the DS Newborns WhoPassed Their NBS

Two hundred thirty-two newborns with DS passed their NBS

(Figure 2). One hundred twenty-four children (53.4%) main-tained normal hearing. However, 101 infants developed con-

ductive hearing loss, and 97 (96%) required insertion of

ventilation ear tubes. One child (0.4%) apparently developed a

sensorineural hearing loss. This child was born at 35 weeks

gestation and required admission to the neonatal intensive care

unit shortly after birth for maternal chlamydia, dysphagia, and

cardiomegaly. The chlamydia was treated with antibiotics. His

cardiomegaly resolved following a patent ductus arteriosus

(PDA) ligation; his feedings were transitioned from enteral

feeding to oral by the time he was discharged approximately

14 days later. The mother was concerned about her sons hear-

ing as early as 6 months of age. It is unclear why she did not

obtain audiologic testing for him until he was 4 years old. She

did not know the results of his NBS. Audiologic testing

revealed a right profound and left severe sensorineural hearing

loss. He has been treated with hearing aids.

One child (0.4%) was diagnosed with an indeterminant

hearing loss. ABR testing revealed a mild to moderate bilat-

eral hearing loss. Otoscopic examination showed no evi-

dence of middle ear fluid. No bone conduction testing was

performed to help differentiate the type of hearing loss. He


n = 332

DS Failed NBSn = 87


DS No NBSn = 13

Normal Hearingn = 124(53.4%)

Conductive HLn = 101(43.5%)


(0.4%)

No Follow-upn = 5

(2.2%)

Indeterminantn = 1

(0.4%)

Figure 2. Distribution of hearing loss in patients with Down syndrome (DS) who passed their newborn hearing screening (NBS). HL, hear-ing loss.

Park et al 137


has been treated with hearing aids. Five newborns (2.2%)

with DS were lost to follow-up.

Distribution of Hearing Loss in the DS Newborns WhoDid Not Have NBS

Thirteen newborns (3.9%) with DS did not undergo new-

born hearing screening (Figure 3). Subsequent audiologictesting indicated 1 child (7.7%) with normal hearing and 1

(7.7%) with a conductive hearing loss. That child underwent

ventilation tube insertion, and a later audiogram demon-

strated normal hearing thresholds. Eleven children (84.6%)

had no follow-up audiologic data reported or available.

Overall Breakdown of Hearing Loss Incidence

The overall incidence of hearing loss and hearing loss type

is shown in Figure 4. Of the 332 children with DS evalu-ated, 141 (42.5%) had normal hearing, 153 (46.1%) had a

hearing loss, and 38 (11.4%) had no audiologic data. Of the

153 with hearing loss, 135 (88.2%) had a conductive hear-

ing loss. Six children with DS (3.9%) had a sensorineural

hearing loss; 3 with DS (2.0%) had a mixed loss. Nine chil-

dren (5.9%) had an indeterminant hearing loss.

Discussion

Of the 332 children with DS evaluated, 42.5% had normal

hearing, 46.1% had a hearing loss, and 11.4% were lost to

follow-up. SNHL was detected in 3.9% of hearing loss

patients; a mixed hearing loss was less common at 2.0%.

Our reported rate of conductive hearing loss is similar to a

number of prior studies.6,11-14 Our reported rate of SNHL is

slightly lower than Davies 4% rate.14

More than 96% of all infants with DS born in Utah

between 2002 and 2006 underwent NBS. It is not clear why

13 DS infants did not undergo hearing screening. For other

infants born in Utah, we know that parental refusal and

labor and delivery staff failing to perform audiologic testing

are common reasons for missed NBS. Also, nearly 800

births per year are home births involving a midwife and

are less likely to be screened. The opportunity to obtain

NBS is crucial for these patients because our results indicate

that more than 84% of the infants who did not undergo

NBS did not obtain subsequent audiologic testing.

For the children who underwent NBS, we identified 87

(26.2%) who did not pass their hearing screen. Most were

found to have middle ear effusions requiring ear tube inser-

tions. Not all these patients, however, had normal hearing

following tube insertion. Seven children with DS (21.2%)

had a persistent conductive hearing loss after surgery. This

result is slightly lower than the 40% rate of conductive hear-

ing loss not attributable to middle ear effusion or tympanic

membrane perforation reported by Balkany et al15 but sup-

ports the need for accurate audiologic testing of all patients

with DS following tube insertion.

Every child with DS identified with a mixed hearing

loss, and all but 1 child identified with SNHL failed their

initial NBS. Unfortunately, the time from screening to diag-

nosis of an SNHL was not within the 90-day period recom-

mended by the JCIH.10 Multiple factors appear to influence

the time to diagnosis of hearing loss in this population. As

described earlier, at least 2 children had multiple medical

problems that probably delayed the hearing loss diagnosis.

The known high incidence of conductive hearing loss from

middle ear fluid may have clouded the view of some practi-

tioners. The medical records indicated that some physicians

accepted normal sound field responses as sufficient audiolo-

gic workup for a possible hearing loss. This view is contrary

to our finding that 3 of 5 patients with SNHL had a unilat-

eral hearing loss. Several studies have also reported on the

adverse effects of unilateral hearing loss on speech develop-

ment and quality of life of otherwise developmentally

normal children.16,17 Unilateral hearing loss in developmen-

tally delayed children would also be expected to adversely

affect their speech development and quality of life.

Twenty-two infants with DS (25.3%) who did not pass

their NBS were lost to follow-up or lost to documentation.


n = 332

DS Failed NBSn = 87


DS No NBSn = 13

Normal Hearingn = 1

(7.7%)

No Follow-upn = 8

(61.5%)

Conductive HLn = 4

(30.8%)

Figure 3. Distribution of hearing loss in Down syndrome (DS)patients who did not undergo newborn hearing screening (NBS).HL, hearing loss.

Newborns with DS Alive

n = 332(100%)

DS Normal Hearingn = 141(42.5%)

DS Hearing Lossn = 153(46.1%)

DS no follow-upn = 38

(11.4%)

Conductive HLn = 135(88.2%)


(3.9%)

Mixed HLn = 3

(2.0%)

Indeterminantn = 9

(5.9%)

Figure 4. Distribution of hearing loss in a population with Downsyndrome (DS). HL, hearing loss.



This rate is unfortunately consistent with many universal

newborn hearing screening and intervention programs.18,19

Shulman et al20 reported that 38% of all infants from 46

states and territories surveyed in need of a diagnostic eva-

luation did not receive one. They also noted that less than

half of all infants who failed an initial hearing screening

obtained an evaluation by 3 months of age. Improving sur-

veillance data, ensuring a medical home, increasing subspe-

cialty participation, providing family support programs, and

promoting the importance of early detection have been rec-

ommended to address this challenge.20

One hundred one infants (43.5%) with DS who initially

passed their NBS developed a conductive hearing loss from

middle ear fluid. Almost all these patients required ear tube

insertions. One can conclude from these numbers that regu-

lar otoscopic examination of these patients is critical to

avoid delays in hearing loss diagnosis. The discovery of 1

patient with SNHL following a normal NBS also supports

the need for regular audiologic testing of these children.

Davies14 reported on 1 patient with DS with progressive

SNHL over an 8-year period.

We would advocate a more aggressive and directed

approach toward the evaluation and treatment of children

with DS. Perhaps an approach advocated by Shott et al21

should be implemented. Their group recruited 48 children

with DS for serial otoscopic and audiologic examinations

over a 5-year period. Every child was seen every 6 months;

those with stenotic ear canals (approximately 40% of the

group) were seen every 3 months. Pediatricians were encour-

aged to send children for otolaryngologic microscopic ear

exams if they were unable to visualize the tympanic mem-

branes. An auditory brainstem response study was performed

at least once for every child. Biweekly phone calls were done

to track patient care. The authors noted that 83% of the

patients required ear tube insertion and that they were able to

achieve a 98% normal hearing rate in these patients. They

also reported that only 1 patient was lost to follow-up.

Primary care physicians need to be aware of the rela-

tively high incidence of hearing loss in their patients with

Down syndrome and our relatively poor success in achiev-

ing timely diagnosis and treatment. Perhaps these results are

not surprising because any earlier study by our group

reported a high degree of parental frustration and difficulty

achieving prompt evaluation and intervention in normal

children with hearing loss.18 Perhaps earlier otolaryngology

evaluation is warranted because these children commonly

have very stenotic ear canals, rendering otoscopic examina-

tion challenging, and many of these children will eventually

require insertion of tympanostomy tubes to remove chronic

middle ear effusions. The otolaryngologist can address both

conditions.

A strength of this study was the ability to identify a large

number of patients with DS from a statewide Utah registry

and the ability to use the Utah Department of Healths infor-

mation tracking and management system and IHCs elec-

tronic medical record system. An outstanding collaborative

environment with the Utah Early Hearing Detection and

Intervention (EHDI) staff, Primary Childrens Medical Center

audiology and otolaryngology personnel, made this study

possible. The existence of just 1 childrens hospital in the

state also improved our ability to minimize any lost patients

to follow-up. A limitation of this study is its retrospective

design. Not all the patient data with respect to audiology test-

ing or examinations were available. Physicians whose medi-

cal records are not kept in the IHC electronic medical record

system saw some patients. When an otolaryngologist outside

the IHC system treated a patient, we attempted to contact the

practice for audiologic and otoscopic data.

In summary, patients with Down syndrome present with

a relatively high incidence of conductive, mixed, and sen-

sorineural hearing loss. Providers caring for this particular

population need to be aware of this high rate of hearing

loss. Unfortunately, there continues to be a shortage of spe-

cialists in rural areas who are trained to work with infants

and pediatric patients, and there is a general lack of under-

standing among most parents regarding hearing screening,

follow-up, and hearing loss. Although there has been signifi-

cant improvement recently and physician knowledge and

attitudes regarding hearing loss are improving, the wait-

and-see approach is still pervasive. Therefore, it is not sur-

prising that many state systems, including Utah, have failed

in their ability to consistently meet the national EHDI goals

of screening before 1 month, diagnosis before 3 months,

and referral to appropriate intervention programs before 6

months with these or any other children with special health

care needs.

Author Contributions

Albert H. Park, involved in project conception, analyzed the data,

and rewrote the manuscript; Matt A. Wilson, obtained the data

and wrote the initial manuscript draft; Paul T. Stevens, involved

in the original concept of the project, obtained IRB approval,

obtained the initial data, and involved in reviewing the manuscript;

Richard Harward, involved in the conception of the project and

data acquisition and was instrumental in the analysis and editing of

the article; Nancy Hohler, involved in project conception, data

acquisition, and preparation of the manuscript.

Disclosures

Competing interests: None.

Sponsorships: None.

Funding source: None.

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Identification of Hearing Loss in Pediatric Patients With Down Syndrome