Recommendation 12/6 - 25/4 : Unilateral Hearing loss assesment and councelling after newborn hearing screening (UNHS)

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:

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

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

 

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:

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

 

 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:

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

Then, it will be necessary to recommend:

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

 

Literature:

 

 

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