ScienceWeek

HEARING LOSS

SELECTED ABSTRACTS AND TITLES 2004

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Audiol Neurootol. 2004 Aug 13;9(5):274-281.
  
Bone-Anchored Hearing Aid in Unilateral Inner Ear Deafness: A
Study of 20 Patients.

Hol MK, Bosman AJ, Snik AF, Mylanus EA, Cremers CW.

Department of Otorhinolaryngology, University Medical Centre St.
Radboud, Nijmegen, The Netherlands.

Objective: To evaluate the benefit of a bone-anchored hearing aid
(BAHA) contralateral routing of sound (CROS) in 20 patients with
unilateral inner ear deafness. Subjects: 21 patients were
recruited; 15 had undergone acoustic neuroma surgery and 6
patients had unilateral profound hearing loss due to other
causes; 1 patient was excluded. Only patients with thresholds of
better than 25 dB HL (500-2000 Hz) and an air-bone gap of less
than 10 dB in the best ear were included. Methods: Evaluation
involved audiometric measurements before intervention, when
fitted with a conventional CROS and after implementation and
quantification of the patients' subjective benefit with a hearing
aid-specific instrument: the Abbreviated Profile of Hearing Aid
Benefit (APHAB). Results: Lateralization scores were not
significantly different from chance (50%) in any of the three
conditions. Measurements of speech perception in noise showed an
increase in the signal to noise ratio (S/N ratio) with the
conventional CROS (p = 0.001) and with the BAHA CROS compared to
the unaided condition when speech was presented at the front with
noise on the poor hearing side. On the other hand, a lower S/N
ratio was seen with the BAHA CROS (p = 0.003) compared to the
unaided situation when noise was presented at the front with
speech on the poor hearing side. The patient outcome measure
(APHAB) showed improvement, particularly with the BAHA CROS.
Conclusions: The poor sound localization results illustrate the
inability of patients with unilateral inner ear deafness to
localize sounds. The speech-in-noise measurements reflect the
benefit of a BAHA CROS in lifting the head shadow while avoiding
some of the disadvantages of a conventional CROS. The benefit of
the BAHA CROS was most clearly reflected in the patients' opinion
measured with the APHAB. Copyright 2004 S. Karger AG, Basel

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2: Neurotoxicol Teratol. 2004 Sep-Oct;26(5):629-37.
  
In utero exposure to polychlorinated biphenyls and sensorineural
hearing loss in 8-year-old children.

Longnecker MP, Hoffman HJ, Klebanoff MA, Brock JW, Zhou H,
Needham L, Adera T, Guo X, Gray KA.

Epidemiology Branch, National Institute of Environmental Health
Sciences, National Institutes of Health, Department of Health and
Human Services, P.O. Box 12233, MD A3-05, Research Triangle Park,
NC 27709, USA.

Early-life exposure to polychlorinated biphenyls (PCBs), a
ubiquitous environmental contaminant, increases the hearing
threshold at selected frequencies in rats. Among humans from the
Faroe Islands with unusually high early-life PCB exposure,
exposure was directly associated with increased hearing
thresholds at two frequencies, although the deficits were present
in the left ear but not the right. We examined PCB levels in
maternal pregnancy serum in relation with audiometrically
determined hearing thresholds among offspring when they were of
school age. Complete data were available for 195 children with
sensorineural hearing loss (SNHL) and 615 children selected at
random, all of whom were born in 1959-1966 in the Collaborative
Perinatal Project (CPP) U.S. cohort. The median exposure among
those selected at random, as reflected by the mother's third
trimester serum total PCB concentration, was 2.8 microg/l, about
twofold higher than recent background levels in the United
States. Based on the average hearing threshold across the
frequencies essential for speech recognition in the "worst ear,"
the maternal serum PCB level was unrelated to the adjusted odds
of SNHL or to adjusted mean hearing threshold. Overall, an
adverse effect of early-life, background-level PCB exposure on
SNHL was not supported by these data.

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Ann Univ Mariae Curie Sklodowska [Med]. 2003;58(1):33-7.

Bone and air conduction after stapedectomy.

Morshed K, Siwiec H, Szymanski M, Golabek W.

Otolaryngology Department, Medical University of Lublin, Lublin,
Poland.

Otosclerosis causes loss of air conduction (AC) but also bone
conduction (BC) may be deteriorated. It is reported that also BC
may improve after surgical treatment of otosclerosis. The
investigation was carried out in a group of 50 patients treated
due to otosclerosis in our institution. The group included 34
women and 16 men, at the age 24 to 55 years. Pure-tone audiometry
for bone and air conduction threshold was performed in all the
patients. Hearing tests were carried out before and 2-4 months
after the operation by the same technician Partial. Only patients
with air-bone gap closure were included in the study. Sapedectomy
was performed under local anaesthesia. RESULTS: Significant
improvement of AC was obtained after stapedectomy. There was also
significant improvement of BC at all the frequencies examined of
6-12 dB and it depended on BC threshold before surgery. In the
group of 37 patients with BC threshold before surgery > or = 30
dB a significant improvement of BC after stapedectomy developed.
In the group of 14 patients with BC threshold before surgery < 30
dB the change of BC after stapedectomy was not significant.
Successful stapedectomy improves bone conduction. It means that
in patients with otosclerosis there is a reversible BC pseudo
hearing loss and it is related to BC threshold before the
operation.

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J Deaf Stud Deaf Educ. 2004 Summer;9(4):459-61.
  
Relative Earnings of Deaf and Hard-of-hearing Individuals.

Jones DD.

Economic Consulting Services, 528 Marshall Avenue, St. Paul, MN
55102. DDJ44@ComCast.net

Much has been written, over several decades, about the economic
damage done by hearing loss. This article compares earnings of
male and female deaf or hard-of-hearing college graduates to
those of the general population with the same levels of
education. Although those hard of hearing appear to reach lower
levels of education, with education there is little or no
evidence of an earnings lag relative to those without hearing
loss.

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J Deaf Stud Deaf Educ. 2004 Summer;9(4):427-41.
  
Students with an undisclosed hearing loss: a challenge for
academic access, progress, and success?

Richardson JT, Long GL, Woodley A.

Institute of Educational Technology, The Open University, Walton
Hall, Milton Keynes MK7 6AA, United Kingdom.
J.T.E.Richardson@open.ac.uk

It has been suggested that only 8% of postsecondary students in
the United States who have a hearing loss have disclosed that
hearing loss to their institutions. Consistent with this
suggestion, two anonymous surveys of students enrolled in courses
with the Open University in the United Kingdom suggested that
there were roughly 9,000 students in the Open University itself
and over 42,000 students in higher education across the United
Kingdom as a whole who had a hearing loss that they had not
disclosed to their institutions. These students tended to be
older people with a relatively mild hearing loss that did not
disrupt their communication with other students or their active
engagement with learning activities. The impact of the students'
hearing loss upon their approaches to studying seemed to be
relatively slight, but it was associated with an increase in the
students' perceived academic workload.

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Am J Perinatol. 2004 Aug;21(6):329-32.
  
Use of furosemide and hearing loss in neonatal intensive care
survivors.

Rais-Bahrami K, Majd M, Veszelovszky E, Short BL.

Department of Neonatology, Children's National Medical Center,
and The George Washington University School of Medicine,
Washington, District of Columbia.

Hearing loss is a significant morbidity in survivors of the
neonatal intensive care unit (NICU). The overall prevalence of
hearing loss in neonates is 0.93 per 1000 live births, whereas in
neonates weighing less than 2000 g, it is as high as 15.5 per
1000 live births. The increased incidence of hearing loss in NICU
graduates has been attributed to their underlying disease process
as well as exposure to ototoxic drugs including furosemide. A
retrospective chart review of all neonatal intensive care
survivors was done to evaluate the potential effect of furosemide
on hearing loss. From July 2000 to January 2002, there were 57
neonates who received and 207 neonates who did not receive
furosemide. The incidence of abnormal hearing screen was 15.5% in
the furosemide group and 15.9% in the nonfurosemide group ( p =
0.9). Although the incidence of hearing loss is significantly
higher in NICU graduates in comparison with the general neonatal
population, it does not seem to be directly related to the use of
furosemide.

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Brain Res. 2004 Sep 3;1019(1-2):201-9.
  
Delayed production of free radicals following noise exposure.

Yamashita D, Jiang HY, Schacht J, Miller JM.

Kresge Hearing Research Institute, University of Michigan, Ann
Arbor, MI, USA.

Reactive oxygen and reactive nitrogen species (ROS, RNS) formed
in the inner ear in response to high-intensity noise are thought
to play an important role in noise-induced hearing loss (NIHL).
ROS appear rapidly and transiently in the inner ear during and
following noise exposure, while hair cell loss progresses over
time stabilizing two or more weeks after insult. Although the
delayed loss may, in part, reflect slowly progressing apoptotic
or necrosis pathways, an alternate hypothesis is that a continued
formation of free radicals contributes to cell death. To evaluate
this hypothesis, we measured auditory brain stem responses
(ABRs), hair cell loss, and free radical activity in the guinea
pig following noise exposure (5 h, 120 dB SPL, 1 OCB).
Nitrotyrosine (NT) and 4-hydroxy-2-noneal (4-HNE) were used as
histochemical markers of RNS and ROS formation, respectively.
Assessments were performed prior to and on Days 1, 3, 7, 10, 14
and 21 after exposure. Immunoreactivity to NT and 4-HNE was low
initially, reached a maximum at 7 to 10 days, and then declined.
ABR thresholds increased maximally immediately after exposure,
with partial recovery stabilizing at 7 to 10 days. Correlating
with the delayed formation of ROS/RNS, there was a progressive
hair cell loss, stabilizing at approximately 2 weeks. Based on
these findings, we suggest that initial hair cell damage after
noise may primarily reflect mechanical events plus transient
intense ROS formation, while continued formation of ROS/RNS
contributes to the long-term hair cell loss. The late formation
of free radicals may provide a window of opportunity for
pharmacological rescue immediately following exposure, requiring
both ROS and RNS scavengers.

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J Deaf Stud Deaf Educ. 2004 Winter;9(1):120-8.
  
Socialization experiences and coping strategies of adults raised
using spoken language.

Bain L, Scott S, Steinberg AG.

Children's Seashore House at The Children's Hospital of
Philadelphia, 3535 Market St., 9th Floor, Philadelphia, PA 19104.
drannie@mail.med.upenn.edu

This investigation concerned the socialization experiences and
coping strategies of a group of 28 deaf adults who were raised
using spoken language. Most respondents reported some level of
social isolation because of (1) limitations in communication with
hearing peers; (2) missing information in social, academic, and
work settings; and (3) a sense of being "different." Most
participants also reported strategies used to reduce isolation
and mitigate the social difficulties associated with their
hearing loss.

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J Deaf Stud Deaf Educ. 2004 Winter;9(1):68-85.
  
Academic engagement in students with a hearing loss in distance
education.

Richardson JT, Long GL, Foster SB.

Institute of Educational Technology, The Open University, Walton
Hall, Milton Keynes MK7 6AA, United Kingdom.
J.T.E.Richardson@open.ac.uk

This investigation compared 267 students with a hearing loss and
178 students with no declared form of disability who were taking
courses by distance learning in terms of their scores on an
abbreviated version of the Academic Engagement Form. Students
with a hearing loss obtained lower scores than students with no
disability with regard to communication with other students, but
some felt that communication was easier than in a traditional
academic situation. Students who were postvocationally deaf had
lower scores than students with no disability on learning from
other students, but they obtained higher scores on student
autonomy and student control. In general, the impact of a hearing
loss on engagement in distance education is relatively slight.

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Int J Pediatr Otorhinolaryngol. 2004 Sep;68(9):1193-8.

Systematic review of the etiology of bilateral sensorineural
hearing loss in children.

Morzaria S, Westerberg BD, Kozak FK.

Division of Pediatric Otolaryngology, British Columbia Children's
Hospital, 4480 Oak Street, Vancouver, BC, Canada V6H 3V4.

Objective: Identification of the etiology of sensorineural
hearing loss (SNHL) in children facilitates management and
provides important prognostic information. In recent years, the
etiology of bilateral SNHL in children has changed due to
advances in genetic testing and treatment of perinatal
infections. The objective of this study was to determine the
frequency of etiologies of moderate-profound bilateral
sensorineural hearing loss (SNHL) in children. Methods: The
English literature was searched in Medline for articles published
between 1966 and 2002. The inclusion criteria were studies
involving bilateral SNHL >/=40dB in children less than 18 years
of age. The studies were required to account for all patients,
and provide a breakdown of etiologic factors. Etiologies
investigated included genetic and non-genetic (prenatal,
perinatal, postnatal). To compare differences between the
frequencies of etiologies a two-sample t-test was performed
assuming unequal variance. Studies were stratified according to
perceived confounders: start date of study, study design, and
degree of hearing loss. Results: Seven hundred and eighty
abstracts were screened for relevancy. Forty-three studies
satisfied the inclusion criteria. The common etiologies of
bilateral SNHL were unknown (41.5%), genetic non-syndromic
(27.2%), prenatal (11.5%), perinatal (9.7%), postnatal (6.6%),
and genetic syndromic (3.5%). Unknown and Rubella were
significantly less frequent etiologies in the more recent
studies, while genetic non-syndromic, asphyxia and prematurity
were more common. Genetic non-syndromic hearing loss was more
frequent in the prospective studies compared to the population
and retrospective studies, but this difference was not
significant. Genetic non-syndromic hearing loss was more common
among patients with profound hearing loss. Conclusion: Accounting
for the recent decline in infectious etiologies, the most common
causes of bilateral SNHL are unknown (37.7%), genetic non-
syndromic (29.2%), prenatal (12%), perinatal (9.6%), postnatal
(8.2%), and genetic syndromic (3.2%).

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Int J Pediatr Otorhinolaryngol. 2004 Sep;68(9):1141-8.

Improvement of motor development and postural control following
intervention in children with sensorineural hearing loss and
vestibular impairment.

Rine RM, Braswell J, Fisher D, Joyce K, Kalar K, Shaffer M.

Department of Orthopaedics and Rehabilitation, Division of
Physical Therapy, School of Medecine, University of Miami, 5915
Ponce de Leon Blvd., 5th Floor Plumer Building, Coral Gables, FL
33146, USA.

Objective: The purpose of this study was to determine the effect
of exercise intervention on the progressive motor development
delay and postural control impairments in children with
sensorineural hearing loss and concurrent vestibular impairment.
Methods: Twenty-one children with sensorineural hearing loss and
vestibular impairment were randomly assigned to two groups
(exercise and placebo) matched for age and gross motor
development level. Exercise intervention consisted of
compensatory training, emphasizing enhancement of visual and
somatosensory function, and balance training. Placebo
intervention focused on language development activities. Each
intervention was administered three times weekly for 12 weeks.
Motor development and posturography testing was completed pre-
and post-intervention. To examine the mechanisms of change,
somatosensory, visual and vestibular functional effectiveness
ratios were calculated from posturography stability scores.
Children in the placebo group later participated in exercise
intervention, and a second post-test completed. Data were
analyzed by group, as well as merged once all had received
exercise intervention. Results: Post-intervention, motor
development scores significantly improved in the exercise, not
the placebo group ( [Formula: see text] ). Although not
significant, improvement in posturography scores were evident in
the exercise group. Once the post-exercise data from both groups
were merged ( [Formula: see text] ), improvements in these scores
were significant (<==0.02). The difference from the normative
sample was eliminated. Conclusions: Exercise intervention focused
on the enhancement of sensory integrative postural control
abilities is effective for the arrest of the progressive motor
development delay in children with sensorineural hearing loss and
vestibular impairment.

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Hum Mutat. 2004 Sep;24(3):274-5.
  
Impaired calmodulin binding of myosin-7A causes autosomal
dominant hearing loss (DFNA11).

Bolz H, Bolz SS, Schade G, Kothe C, Mohrmann G, Hess M, Gal A.

Institut fur Humangenetik, Universitatsklinikum Hamburg-
Eppendorf, Butenfeld 42, Hamburg, Germany.

Both myosin 7A (MYO7A) and calmodulin (CaM) are required for
transduction and adaptation processes in inner ear hair cells. We
identified a novel heterozygous missense mutation (c.2557C>T;
p.R853C) in a family with autosomal dominant non-syndromic
hearing loss that changes an evolutionarily invariant residue of
the fifth IQ motif (IQ(5)), a putative calmodulin (CaM) binding
domain, of MYO7A. Functional effects of the p.R853C mutation were
investigated in a physiological cellular environment by
expressing MYO7A IQ(5)-containing peptides in smooth muscle cells
of microarteries, in which overexpression of wildtype IQ(5) (with
intact calmodulin binding) would be expected to compete with
myosin light chain kinase (MLCK) for CaM binding. Indeed,
analysis of calmodulin-dependent vasoconstriction suggests
constitutive binding of CaM to the wildtype, but not the p.R853C-
mutated IQ(5) motif at all physiologically relevant Ca(2+)
concentrations. Thus our data suggest a disturbed CaM/MYO7A
binding of the p.R853C mutant, this amino acid change may result
in impaired adaptation to environmental stimuli and progressive
deterioration of hearing transduction in heterozygotes. A defect
in CaM/MYO7A interaction represents a novel pathomechanism for
genetic hearing loss. It provides an attractive molecular target
for therapeutic interventions aimed to delay or prevent the onset
of hearing loss in families with mutations in myosin IQ domains.
Copyright 2004 Wiley-Liss, Inc.

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Z Arztl Fortbild Qualitatssich. 2004 Jun;98(4):265-70.

[Early diagnosis of hearing impairment in children]

[Article in German]

Ptok M.

Klinik und Poliklinik fur Phoniatrie und Padaudiologie,
Medizinische Hochschule Hannover, Hannover. Ptok.Martin@MH-
Hannover.de

Hearing loss can be attributed to a variety of causes. In infants
early detection of hearing loss coupled with an appropriate
intervention is critical to their speech, language, cognitive and
social development. Despite the fact that several methods exist
to uncover hearing impairment beyond any doubt, permanent hearing
loss in children is still being detected much too late in
Germany. This calls for universal new-born hearing screening and
adequate audiometric testing in children that their parents
either suspect may suffer from a hearing problem or have other
risk factors.

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Eur J Hum Genet. 2004 Aug 4 [Epub ahead of print] Related
Articles, Links  
  
Mitochondrial DNA mutations in patients with postlingual,
nonsyndromic hearing impairment.

Jacobs HT, Hutchin TP, Kappi T, Gillies G, Minkkinen K, Walker J,
Thompson K, Rovio AT, Carella M, Melchionda S, Zelante L,
Gasparini P, Pyykko I I, Shah ZH, Zeviani M, Mueller RF.

[1] 1Institute of Medical Technology & Tampere University
Hospital, Tampere, Finland [2] 2IBLS Division of Molecular
Genetics, University of Glasgow, UK.

Mitochondrial mutations have previously been reported anecdotally
in families with maternally inherited, nonsyndromic hearing
impairment. To ascertain the contribution of mitochondrial
mutations to postlingual but early-onset, nonsyndromic hearing
impairment, we screened patients collected from within two
different populations (southern Italy and UK) for previously
reported mtDNA mutations associated with hearing disorders.
Primer extension (SNP analysis) was used to screen for specific
mutations, revealing cases of heteroplasmy and its extent. The
most frequently implicated tRNA genes, Leu(UUR) and Ser(UCN),
were also sequenced in all Italian patients. All tRNA genes were
sequenced in those UK patients showing the clearest likelihood of
maternal inheritance. Causative mtDNA mutations were found in
approximately 5% of patients in both populations, representing
almost 10% of cases that were clearly familial. Age of onset,
where known, was generally before adulthood, and hearing loss was
typically progressive. Haplogroup analysis revealed a possible
excess of haplogroup cluster HV in the patients, compared with
population controls, but of borderline statistical significance.
In contrast, we did not find any of the previously reported mtDNA
mutations, nor a significant deviation from haplogroup cluster
frequencies typical of the control population, in patients with
late adult-onset hearing loss (age-related hearing impairment)
from the UK or Finland.European Journal of Human Genetics advance
online publication, 4 August 2004; doi:10.1038/sj.ejhg.5201250

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Ear Hear. 2004 Aug;25(4):388-396.

Hearing Loss Associated With Ear Infections in Nord-Trondelag,
Norway.

Tambs K, Hoffman HJ, Engdahl B, Borchgrevink HM.

Epidemiology Section, Norwegian Institute of Public Health, N-
0403 Oslo, Norway (K.T.); Epidemiology and Biostatistics,
National Institute on Deafness and Other Communication Disorders
(NIDCD), National Institutes of Health, Bethesda, Maryland
(H.J.H.); Department of Environmental Medicine, Norwegian
Institute of Public Health, N-0403 Oslo, Norway (B.E.); and
Norwegian Research Council, Oslo, Norway (H.M.B.).

OBJECTIVE:: We have assessed the effect of recurrent childhood
ear infections on adult hearing. We also examined whether adult
hearing is poorer with an early age of onset of ear infections
compared with later onset. DESIGN:: A population-based cohort of
50,398 subjects, 20 yr of age or older, were examined with air-
conduction, pure-tone audiometry and reported if they had had
recurrent ear infections (EI) in childhood (or subsequently) with
the age of onset. RESULTS:: There were poorer hearing thresholds
associated with recurrent EI for all frequency ranges from 0.25
kHz to 8 kHz, regardless of age or gender. The effect increased
with age from approximately 2 dB among younger subjects (20 to 44
yr old) to approximately 5 to 6 dB among older subjects (65 yr or
older). Among younger subjects, the effect of EI was somewhat
stronger for men, whereas among older subjects the effect was
somewhat stronger for women. Early age of onset for EI was
associated with poorer hearing thresholds than late onset. The
mean loss was close to 9 to 10 dB for all frequency ranges among
older subjects reporting onset of EI before 2 yr of age. The mean
loss was only about 4 dB among older subjects reporting onset of
EI after 7 yr of age. CONCLUSIONS:: Reported EIs are associated
with similar consequences in terms of reduced hearing across
frequencies 0.25 to 8 kHz for male and female subjects. The
observed effects are stronger among older than among younger
subjects, perhaps because effects increase with age or possibly
because EI affected the hearing more before 1940 than during
subsequent decades. Reported early age of onset of EI increases
the risk of a substantially reduced hearing level later in life.

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Occup Med (Lond). 2004 Aug;54(5):290-6.
  
Noise-induced hearing loss and hearing conservation in mining.

McBride DI.

Senior Lecturer in Occupational Health, Department of Preventive
and Social Medicine, University of Otago, PO Box 913, Dunedin,
New Zealand.

BACKGROUND: Noise exposure is prevalent in mining, and as the
prevalence of noise-induced hearing loss has not changed much in
the past two decades, hearing conservation is an important issue.
Objectives To review the literature and highlight important
developments in the field. METHODS: A review of the literature
using OVID as the primary search engine, using the search terms
as: noise, occupational; hearing loss, noise induced; ear
protective devices; and mining. RESULTS: A total of 66 articles
were found, but only 11 were in the English language and few were
published in the past 10 years. This is disappointing, because
neither noise exposure nor the consequent risk of noise-induced
hearing loss seems to have changed much in the past 20 years.
Noise is, however, a generic hazard, and this article reviews
current best practice in prevention.

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Exp Gerontol. 2004 Aug;39(8):1253-8.
  
Age-dependent modifications of expression level of VEGF and its
receptors in the inner ear.

Picciotti P, Torsello A, I Wolf F, Paludetti G, Gaetani E, Pola
R.

Institute of Otolaryngology, A. Gemelli University Hospital,
Universita Cattolica del Sacro Cuore School of Medicine, Rome,
Italy.

The mechanisms responsible for age-associated hearing loss are
still incompletely characterized. In this study, we used a murine
model of age-dependent hearing loss and evaluated whether this
condition is associated with vascular modifications of the
structures of the inner ear. We used old C57BL/6J mice that are
affected by rapid and severe age-related hearing loss, and
analyzed the expression pattern of vascular endothelial growth
factor (VEGF), a prototypical angiogenic cytokine, and its
receptors Flt-1 and Flk-1 in the inner ear. We report for the
first time morphological and quantitative data about the
expression of these crucial angiogenic molecules in the murine
cochlea. We also show that in this animal model, cochlear VEGF
expression is significantly reduced as a function of age. Our
findings provide new evidence of possible interdependent
relationships between aging, VEGF, and presbycusis, suggesting
that vascular abnormalities might play a role in aging-associated
hearing loss, with potentially important fundamental and clinical
implications.

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Genet Couns. 2004;15(2):213-8.


Hereditary gingival fibromatosis and sensorineural hearing loss
in a 42-year-old man with Jones syndrome.

Kasaboglu O, Tumer C, Balci S.

Hacettepe University, Faculty of Dentistry, Department of Oral
and Maxillofacial Surgery, Ankara, Turkey.
okasabog@hacettepe.edu.tr

Hereditary gingival fibromatosis and sensorineural hearing loss
in a 42-year-old man with Jones syndrome: Gingival fibromatosis
is a rare disease, which can be seen as an isolated condition or
associated with some uncommon syndromes. This case report
describes the evaluation and treatment of a 42-year-old male
patient with hereditary gingival fibromatosis, sensorineural
hearing loss, undescended testis and maxillary odontogenic cyst
(Jones Syndrome). Six years follow up of the index patient after
the surgery revealed no recurrence of the gingival fibromatosis.
This report also describes the anamnestic data of the patient's
family that showed progressive deafness and gingival enlargement
in three generations.

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Hosp Med. 2004 Jul;65(7):392-5.


New aspects of inner ear research.

Brors D, Bodmer D.

Department of Otorhinolaryngology, University of Wurzburg, 97080
Wurzburg, Germany.

At birth, one in 850 babies are profoundly deaf, and hearing loss
affects more than 50% of all people over 60 years of age. While
hearing loss caused by disease of the external and/or middle ear
is treatable, hearing loss as a result of damage to and loss of
hair cells and/or auditory neurons can only be alleviated using
prosthetic devices such as hearings aids or cochlear implants.

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J Med Genet. 2004 Aug;41(8):591-5.
  
Mutations of ESPN cause autosomal recessive deafness and
vestibular dysfunction.

Naz S, Griffith AJ, Riazuddin S, Hampton LL, Battey JF Jr, Khan
SN, Riazuddin S, Wilcox ER, Friedman TB.

Section on Human Genetics, LMG, NIDCD, NIH, Rockville, MD 20850,
USA.

We mapped a human deafness locus DFNB36 to chromosome 1p36.3 in
two consanguineous families segregating recessively inherited
deafness and vestibular areflexia. This phenotype co-segregates
with either of two frameshift mutations, 1988delAGAG and
2469delGTCA, in ESPN, which encodes a calcium-insensitive actin-
bundling protein called espin. A recessive mutation of ESPN is
known to cause hearing loss and vestibular dysfunction in the
jerker mouse. Our results establish espin as an essential protein
for hearing and vestibular function in humans. The abnormal
vestibular phenotype associated with ESPN mutations will be a
useful clinical marker for refining the differential diagnosis of
non-syndromic deafness.

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J Laryngol Otol. 2004 Jun;118(6):450-2.
  
Sudden hearing loss in intralabyrinthine haemorrhage in a child.

Jang CH, Kim YH.

Department of Otolaryngology, Wonkwang Medical School, Iksan,
South Korea. chulsavio@hanmail.net

This paper reports an unusual case in which aseptic meningitis
presented with sudden sensorineural hearing loss (SSNHL)
associated with intralabyrinthine haemorrhage (ILH). A seven-
year-old girl presented with sudden right-sided hearing loss with
dizziness. She did not have a previous history of bleeding
disorders. This child was assessed using audiograms and magnetic
resonance imaging (MRI). The patient's hearing loss was
irreversible. Steroid therapy was not effective. SSNHL associated
with ILH can be one of the negative prognostic factors in
children.

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J Laryngol Otol. 2004 Jun;118(6):413-6.
  
Noise exposure in orthopaedic practice: potential health risk.

Ullah R, Bailie N, Crowther S, Cullen J.

Department of Otorhinolaryngology, Altnagelvin Hospital,
Glenshane Road, Londonderry, Northern Ireland.

Noise exposure is one of the major causes of permanent hearing
loss in society. Exposure of health service staff to intense
levels of noise in the workplace is a potential risk for the
development of temporary and permanent hearing loss. In this
prospective study, 18 members of the orthopaedic staff underwent
hearing assessment by pure tone audiometry and speech
discrimination prior to noise exposure at the workplace and
immediately following cessation of work. The number of hours of
exposure and noise levels in the workplace was also analysed.
Only minimal temporary sensorineural threshold shifts were
detected post-noise exposure. There was no change in speech
discrimination scores and no individuals complained of tinnitus.
The number of hours of exposure ranged from 1.5 to 8.5 hours
(mean 5.2 hours). Recorded sound levels for instruments ranged
from 119.6 dB at source to 73.1 decibels at 3 metres. Although
high sound levels are recorded in the orthopaedic operating
theatre, the intermittent nature exposure to the intense noise
may protect staff against hearing loss, speech discrimination
difficulties and tinnitus.

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