AUDIOMETRISCHE CLASSIFICATIE VAN GEHOORSTOORNISSEN

 

Gehoorstoornissen zijn meestal gekoppeld aan een verminderde perceptie van geluiden, meer

bepaald van spraakklanken. Spraak bestaat uit hoge en lage frequenties waarvan de

akoestische energie varieert en bijgevolg niet kan herleid worden tot één gemiddeld

akoestisch niveau.

Na een klinisch onderzoek wordt een audiometrisch onderzoek uitgevoerd in aanvaardbare

akoestische omstandigheden. Dit toont een verlies in decibel ten opzichte van het normaal

gehoor (dB HL) volgens de ISO-normen.

Het gemiddelde gehoorverlies wordt berekend op basis van het verlies in dB voor de

frequenties 500 Hz,1000 Hz, 2000 Hz en 4000 Hz. Een niet waargenomen frequentie wordt

beschouwd als een verlies van 120dB. De som wordt gedeeld door 4 en naar boven afgerond.

In geval van asymmetrisch gehoorverlies wordt het gemiddelde gehoorverlies in dB

vermenigvuldigd met 7 voor het beste oor en met 3 voor het slechtste oor. De som wordt

gedeeld door 10.

 

I.  Normaal of subnormaal gehoor

Het gemiddelde tonaal verlies bedraagt niet meer dan 20 dB.

Het gaat eventueel om een discreet gehoorverlies zonder sociale weerslag.

 

II. Licht gehoorverlies

Gemiddeld tonaal verlies tussen 21 dB en 40 dB.

De normale spreekstem wordt waargenomen; de zachte stem of een spreker die zich veraf

bevindt wordt moeilijk waargenomen.

Het merendeel van de vertrouwde geluiden wordt waargenomen.

 

III. Matig gehoorverlies

Eerste graad : gemiddeld tonaal verlies tussen 41 dB en 55 dB.

Tweede graad : gemiddeld tonaal verlies tussen 56 dB en 70 dB.

De spraak wordt waargenomen indien men de stem verheft. Men verstaat beter als men ziet

spreken. Enkele vertrouwde geluiden worden nog waargenomen.

 

IV. Ernstig gehoorverlies

Eerste graad : gemiddeld tonaal verlies tussen 71 dB en 80 dB.

Tweede graad : gemiddeld tonaal verlies tussen 81 dB en 90 dB.

De spraak met luide stem vlakbij het oor wordt waargenomen.

Sterke geluiden worden waargenomen.

 

V. Doofheid

Eerste graad : gemiddeld tonaal verlies tussen 91 dB en 100 dB.

Tweede graad : gemiddeld tonaal verlies tussen 101 dB en 110 dB.

Derde graad : gemiddeld tonaal verlies tussen 111 dB en 119 dB.

Geen enkele waarneming van de spraak.

Enkel zeer sterke geluiden worden waargenomen.

 

VI. Totaal gehoorverlies – anakoesie

Gemiddeld tonaal verlies van 120 dB.

Er wordt niets waargenomen.

 

1 mei 1997, Lissabon (Portugal)

 

  • Hits: 20714

Introduction

Until recently most children with a unilateral hearing loss were diagnosed well beyond the age of 6 years and already attending school. With a universal newborn hearing screening program in place using a bilateral up to date hearing screening technique, bilateral as well as unilateral hearing losses are diagnosed within the first few months of life. This requires new and different concepts for the assessment, counselling and rehabilitation of those with a unilateral hearing loss.

Effects of a unilateral hearing loss

Neither audiologists or otolaryngologists nor paediatricians were usually concerned over unilateral hearing losses, other than to identify its aetiology. They also were assuring the parents that there was no handicap. According to their experience a unilateral hearing loss had no effect on the speech and language development of these children.

In contrast to this opinion several studies between 1986 and 1988 show that children with an unilateral hearing loss bear a more than ten times higher risk to fail at least one grade in school. These failures are related to the fact that these children do experience problems in their directional hearing and consequently in their ability to understand speech in noisy situations, as in a regular classroom. These studies additionally name attention and concentration deficits, getting tired in demanding listening situations and a loss of self confidence due to insecurity. Because of the difficulties in directional hearing safety problems for example in the traffic can not be ruled out.

From a neurophysiological standpoint it’s also well documented for bilateral hearing losses that if one ear is not integrated in the hearing process because only one ear is fitted with an hearing aid, that may lead to deprivation of the unfitted ear. 

Epidemiology

In various publications one can find different prevalence numbers of unilateral hearing losses at the time of birth. Different hearing screening projects in Germany show that around a quarter of the hearing impaired babies identified through NHS have unilateral hearing losses

There are also estimates that between 5-10% of unilateral hearing losses are progressive and some of them also turning into a bilateral loss.

The causes, the configuration and the severity of the hearing losses seem to be equally distributed comparing unilateral and bilateral hearing losses. 

Assessment

a. Anamnesis

Taking the case history, special attention should be given to:

1. Symptoms that can be primarily related to a unilateral hearing loss like:

  • being able to telephone properly only on one of the ears
  • not responding to a wake–up call if sleeping on the good ear
  • reduced directional hearing (being unable to locate a caller in a different room at home or an approaching car in the traffic)
  • problems to understand in noisy situations (family gathering, car, kindergarten, school, church)
  • turning always one specific ear towards the speaker
  • hearing especially bad when having a middle ear ventilation disorder on the good ear

2. Some more unspecific symptoms which maybe connected to unilateral losses like:

  • attention and concentration difficulties
  • school problems, missing information, distracting other pupils

3. Some causes that may lead to a unilateral hearing loss:

  • family history
  • pregnancy (CMV.. ), birth, neonatal period
  • infections during childhood (like mumps ......)
  • accidents (skull fractures)
  • malformations of the external ear
  • acoustic trauma

 

b. Examination/Hearing testing

The testing of unilateral hearing losses with young children may be especially difficult because of problems using masking procedures. With babies the diagnostic process may start with a NHS. To find unilateral losses through NHS a protocol that screens each ear separately is necessary. The subsequent audiological diagnostic procedures must follow the same strict time table as with bilateral losses, so that also unilateral losses are diagnosed within the first 6 month of age. All families with a child with a unilateral hearing loss need a thorough counseling by an expert in pediatric audiology. Regardless of further therapeutic procedures a control hearing test should be performed every 3 month during the first year of life then twice a year up to kindergarten, then once a year at least until the end of primary school. 

To assess unilateral hearing losses the audiometric testing should regard the best practice recommendations for bilateral losses and additionally it has to factor in:

  • measure the hearing threshold always separately on each side including an airconduction and a bone conduction threshold
  • using consequent masking with all the hearing test procedures (ABR, VRA, ....),
  • aided thresholds on the impaired side can only yield valid results, if the normal hearing ear is properly masked with a headphone
  • insert earphones should be preferred (because of a greater interaural attenuation)
  • in case of a progressive or newly developed unilateral hearing loss a MRI scan and a  vestibular testing is recommended

Concerning therapeutic procedures a categorization of unilateral hearing losses in the following subgroups is helpful (also see the annex on hearing aid fitting):

  • Unilateral moderate sensoneural hearing-loss or conductive hearing loss without atresia and normal hearing on the opposite ear
  • Unilateral severe and profound deafness and normal hearing on the opposite ear
  • Unilateral conductive hearing-loss (e.g. major aplasia, severe ear canal atresia) and normal hearing on the opposite ear

 

 Accompanying and Counselling of the parents

(co-operation with commission 25)

 

When the diagnosis of an unilateral deafness is established, in particular within the framework of a systematic newborn hearing screening program the BIAP recommends the installation of an early parental counselling and support by an expert in paediatric audiology. Also reassuring the parents, that almost all children will learn to listen and to peak like all other children despite their unilateral hearing loss, therefore any overprotection should be avoided.

The program of accompanying parents aims at:

  • to listen and to reassure the parents confronted with the diagnosis
  • to allow them to express their possible concerns or guilt
  • to meet their need for information

It will be necessary to explain to the parents the importance:

  • of a regular monitoring of the child’s hearing in both ears (probably at 6 month, 1year and if not progressive then at least once a year) by an ORL or paediatric audiologist
  • of a monitoring of the development of the prelinguistic communication skills and consecutively the development of speech and language (assessment during the first 3 years, see CT 24)
  • of a need to adapt their communication behaviour to the child’s needs

Then, it will be necessary to recommend:

  • an information of the teacher in kindergarten and in school
  • an evaluation of the first steps of knowledge acquisition in school
  • an information of potential risks of the practice of extreme sports (risk of head trauma, hypoxia, barotrauma ...).

Explaining the effects of a unilateral hearing loss the information for the parents and the teachers should include the following considerations:

  • Loss of directional hearing
  • Safety concerns in the traffic
  • Orientations problems when reacting to calling
  • Problems to hear and to understand in noisy situations, especially in kindergarten, school (+ entitlement for special integration services)
  • Adaptation of the acoustical environment to optimize the auditive reception in every communication situation to enhance speech understanding: e.g. to place the child well in regard to its best ear in the classroom.
  • Sound protection for the better hearing ear
  • Listening to loud music
  • Playing certain musical instruments
  • Noise at work or during leisure activities
  • Protection of the better ear against ototoxic drugs (also avoiding certain ear drops)
  • Effects of an additional conductive hearing loss (e.g. chronic otitis media with effusion)
  • 0ption of fitting technical devices (e.g. hearing aid, FM-system)

 

Literature:

 

  • BIAP Recommendation 25-1, Guidance of parents whose children suffer from hearing impairments
  • Davis A., Reeve K., Hind S.; Bamford J., 2002, Children with mild and unilateral hearing impairment, In R. Seewald and J. Gravel (eds.), A sound foundation through early amplification: Proceedings of the second international conference (pp. 179-186). Stäfa, Switzerland: Phonak
  • Ross D.S., Holstrum W.J., Mild and Unilateral Hearing Loss: Summaries of Research

 

Articles, National Center on Birth Defects and Developmental Disabilities,

http://www.cdc.gov/ncbddd/EHDI/unilateralhi.htm

 

This recommendation is based on a multidisciplinary cooperation and the cooperation of commission 12 and 25.

President of the commission 12: Th. Wiesner (Germany)

President of the commission 25: S. Demanez (Belgium)

Members of the commission 12: M. Antoniadis-Hitoglou (Greece), A. Bohnert (Germany), P. Chapuy (France), A. Enderle (Germany), M. Delaroche (France), J.P. Demanez (Belgium) , L. Demanez (Belgium), G. Dessy (Belgium), D. Hennebert (Belgium), N. Herman (Belgium), C. van der Heyden (Belgium), A. Juarez Sanchez (Spain), V. Leflere (Belgium), J. Leman (France), Th. Lhussier (Belgium), B. Martiat (Belgium) , N. Matha (France), N. Melis (France), T. Renglet (Belgium), Ph. Samain (Belgium), M.-N. Serville (Belgium), G. Schram (Switzerland), P. Verheyden (Belgium)

Members of the commission 25:

M.-H. Chollet (France), M. Drach (Germany), M. Franzoni (France), N. Herman (Belgium), M.-F. Leman (France), S. Quertinmont (Belgium), T. Renglet (Belgium), A. Tarabbo (France), V. Touma (Lebanon)

Keywords: unilateral hearing loss, unilateral deafness, infant, neonatal screening, interdisciplinary health team, parental guidance, assessment, early intervention, early diagnosis.

 

Accepted by the general assembly, Bordeaux May 2009

 

 

  • Hits: 24239

As it is no longer a question whether a UNHS is feasible even on a national level, indicators show that a rehabilitation program including the fitting of hearing aids starting before 6 months of age can improve communication skills that are near the lower limit of a normal hearing child.

Yet the preconditions for this goal can only be achieved if UNHS interacts and is embedded in a multidisciplinary framework of audiological, medical, therapeutical and pedagogical services (14-1 bis) specialised in working with babies and their families (25-1, 25-2).

 

BIAP therefore endorses UNHS and encourages its member organisation to set up and promote a framework of multidisciplinary cooperation starting with an early identification by UNHS and continuing with a well founded early diagnosis. This will ensure an early rehabilitation before 6 months of age.

 

The multidisciplinary cooperation includes:

1. Already in the planning phase

obstetrician, pediatrician, audiologist, ENT-physicians, nurses, midwives, parents-associations, other services involved in the birth itself and its aftercare

2.The Screening itself needs

    1. In a clinical setting:
      obstetrician, pediatrician, nurses, ENT, coordinator
    2. In an outpatient setting:
      midwives, nurses, pediatrician/GP, ENT, coordinator
  1. Second stage screening for the babies, who failed or missed the first screening (as soon as possible within 2 weeks):

birthing hospital, paediatrician, ENT, paediatric audiology other services involved in the birth itself and its aftercare,

  1. Confirmation, diagnosis and inducing services
    1. Full scale hearing testing:
      paediatric audiology, audiology, ENT (preferably specialised in paediatric audiology)
    2. Establishing a “working diagnosis” (diagnosis in process) by 3 months:
      paediatric audiology, ENT specialised in paediatric audiology
    3. Family support (learning to live with the diagnosis + adapting to the new demands and new social circumstances):
      parental guidance (25/1, 25/2, 21), parent support group, early interventionist, social services
    4. further interdisciplinary assessment to determine the origin of the hearing loss and/or to rule out other disabilities:
      e.g. paediatrician, geneticist ….
  2. The rehabilitation requires a multidisciplinary approach (*) starting as soon as possible but well before 6 months of age
    1. Early intervention / early promotion of communication skills
      e.g. speech therapist, special pedagogue, early interventionist,
      psychologist ….
    2. Early fitting of technical devices (e.g. hearing aid, FM-System, Vibrator …)
      prescribed by an ENT specialised in paediatric audiology
      and fitted by a paediatric audiologist and /or specialised acoustician,
  3. Tracking and quality management

When ever possible the UNHS should work closely together with other already existing neonatal screening programs, such as the metabolic screening, as all the programs require a similar procedure and assessment of tracking patients:
Data (IT) management, public health services, quality management services

  1. Continuing the existing hearing “screening” programs especially for children at risk and for the late onset hearing losses :

Paediatrician, ENT, paediatric audiologist

When establishing an early intervention program founded on a UNHS, all the professionals involved are confronted with new challenges like further training needs as well as the need to change and adapt pre-existing service practices like:

  • Training of the screening staff/nurses
  • Training of audiologists and early interventionists
  • Adapting and refining paediatric audiometrical procedures:
    utilising the full scale of diagnostic options (e.g. including frequency specific AP, high frequency tympanometry, refined behavioural audiometry…)
  • Adapting and refining paediatric hearing aid fitting procedures:
    utilising individualised transfer functions (e.g. RECD measurements or age appropriate mean transfer values) and special age appropriate fitting algorithms
  • Adapting and refining early intervention procedures:
    informing about and providing unbiased intervention options, supporting the psychological strains of the family …

 

Services should only be provided by specialised professionals and institutions dedicated to cooperate with one another within a common protocol. Well organised ways of information exchange and feedback (including parent organisations) will help overcome initial pitfalls and will be a fundamental safeguard and keystone for an overall and long-term success of the whole UNHS and early rehabilitation program.

 

________________________________________________________

 

The recommendation was approved by the general assembly of the BIAP after the validation by the national committees, 2007 in Rhodos (Greece)

This recommendation is based on a multidisciplinary cooperation

President of the commission: Th. Wiesner (Germany)

Members of the commission: M. Antoniadis-Hitoglou (Greece), A. Bohnert (Germany), P. Chapuy (France), A. Enderle (Germany), M. Delaroche (France), J.P. Demanez (Belgium) + L. Demanez (Belgium), G. Dessy (Belgium), D. Hennebert (Belgium), N. Herman (Belgium), C. van der Heyden (Belgium), A. Juarez Sanchez (Spain), V. Leflere (Belgium), J. Leman (France), Th. Lhussier (Belgium), B. Martiat (Belgium) , N. Matha (France), N. Melis (France), R. Proença Melo (Portugal), T. Renglet (Belgium), Ph. Samain (Belgium), M.-N. Serville (Belgium), G. Schram (Switzerland), P. Verheyden (Belgium)

 

Keywords: Hearing loss, deafness, infant, neonatal screening, newborn, interdisciplinary health team, early intervention, early diagnosis


pdf Recommandation 12.5 - version française  (pdf) pdf

 

 

 

 

 

  • Hits: 22208

La complexité du processus de l'intégration ou coéducation des enfants (ou adolescents) atteints de déficience auditive dans l'enseignement ordinaire rend nécessaire un suivi minutieux de chaque enfant (ou adolescent) afin de pouvoir corriger ou adapter les différentes modalités choisies au départ et d'introduire les changements estimés nécessaires en fonction de l'évolution de l'enfant (ou adolescent), de la nature des soutiens dont il a besoin et des réactions de chacun des partenaires du programme éducatif.

Cette évaluation permanente doit se poursuivre tout au long de la scolarité de l'enfant (ou adolescent) et se fonder sur les données et observations transmises par la famille, les pédagogues et responsables de l'établissement d'accueil ainsi que par les membres de l'équipe spécialisée.



En vue d'une synthèse collective et en faisant référence au projet individualisé d'intégration, les différents partenaires réunis en séance de concertation ont à prendre en considération :



L'enfant (ou adolescent) : son adhésion au projet, sa motivation, son bien être, sa relation avec les enseignants et les autres élèves, sa participation aux activités pédagogiques, son utilisation du langage oral dans la communication, ses résultats scolaires, l'adaptation des modalités de son intégration.



Les parents : leur degré d'implication dans le projet éducatif, leur analyse de l'intégration sociale de l'enfant (ou adolescent) dans le milieu extra-scolaire et de l'incidence du processus de l'intégration ou coéducation sur le comportement.



L'enseignant : les aspects de sa relation avec l'enfant (ou l'adolescent) à l'intérieur de la classe, la qualité de son adaptation pédagogique et de sa collaboration avec la famille et avec l'équipe spécialisée.



La structure d'accueil : le degré d'implication des responsables et des personnels dans le projet d'intégration, la validité des moyens mis en œuvre pour permettre l'intégration, la coordination avec les familles et l'équipe spécialisée.



L'équipe spécialisée : la nature et la cohérence des interventions des différents spécialistes, l'adéquation de ces actions à l'objectif poursuivi, l'articulation avec le travail de l'équipe enseignante, les relations avec la famille.



Un protocole à partir duquel il est possible d'établir une évaluation quantitative et qualitative du processus d'intégration ou coéducation de chaque enfant (ou adolescent) est proposé en annexe sous la forme d'une grille d'observation.



Lisbonne (P) 05/05/1997

Annexe sur demande

  • Hits: 17735
Created by OVER IT | All rights reserved | sitemap | Status | R.O.I.