Research Articles:

Articles included in this section describe clinical studies and reviews of research on various topics related to cochlear implants, hearing aids and assistive technologies. Many of these articles have informative abstracts that are available in the Medline Database produced by the National Library of Medicine. These abstracts provide more in depth information on each article. For those articles where abstracts are available, click on the underlined title of the article.

• Cochlear Implants
  
  • Benefits of Cochlear Implants
    
  • Candidacy
    
  • Educational Programs
    
  • Language Development/Literacy
    
  • Music Appreciation
    
  • Psychological/Social Issues
    
  • Speech Intelligibility
    
  • Speech Perception
    
  • Implantation in Very Young Children
    
  • Implantation in the Elderly
    
• Cholesteatomas
  
  • Overview
    
  • Pediatric Cholesteatomas
    
    • Overview
      
    • Causes
      
    • Diagnosis
      
    • Surgery
      
    • Recurrence
      
  • Adult Cholesteatomas
    
  • Chronic Otitis Media and Cholesteatomas
    
  • Labyrinthine fistulas and cholesteatomas s
    
  • Cellular Biology of Cholesteatomas
    
• Hearing Loss in Children
  
• Hearing Aids and Other Assistive Technology
  
• Related Topics
  
  • Motor and Nonverbal Skills in Deaf Children
    
  • Genetic Factors
    

Cochlear Implants:

Benefits of cochlear implants

Chee GH, Goldring JE, Shipp DB, et al. “Benefits of cochlear implantation in early-deafened adults: the Toronto experience.” Journal of Otolaryngology. 33(1):26-31, 2004 Feb.

Cochlear implant use and benefits were evaluated in 42 early-deafened adult cochlear implant users. The majority of patients use their cochlear implant all their waking hours and continue to depend on lip-reading and hearing as their main mode of communication (although they reported improved lip-reading skills with their cochlear implant). Patients reported greater independence, a greater sense of safety in their environment, and an improved social life. Twenty-nine patients (96.7%) said that they were satisfied with their implant, 28 (93.3%) said that they would go through the same process again, and 27 (90%) said that they would recommend it to a friend in a similar situation. Twenty-nine patients (96.7%) stated that the cochlear implant has had a positive effect on their quality of life.

Cochlear implants have dramatically changed the treatment and outcomes for patients with profound sensorineural hearing loss. Deaf adults and children can be successfully re-integrated into the hearing world through an approach that involves otolaryngologists, audiologists, and speech/language pathologists. As the technology of the cochlear implant advances, the candidacy for these devices continues to broaden. This review addresses the basic technology, candidacy criteria, and important issues in the fields of adult and pediatric cochlear implantation. Cost and future directions in the treatment of the profoundly hearing impaired are discussed.

Cochlear implantation is a valuable procedure with important implications for speech perception and verbal language in children with severe to profound hearing impairment. Auditory rehabilitation, language intervention, and close coordination between parents, schools, and the implant center are necessary for maximum effectiveness. Early identification of hearing loss, early hearing aid use and language intervention, and cochlear implantation by 2 years of age were positive factors for the development of language skills that can approach the levels of normal-hearing children.

Candidacy

This paper reviews the many changes in cochlear implant candidacy. The use and safety of chochlear implantation has advanced. Most devices are now approved for use in patients with severe to profound hearing loss rather than the prior requirement of bilateral profound loss. Surgical techniques have also improved, leading to a decrease in complications. The resulting improvements in safety and effectiveness have further encouraged the use of these devices.

Cochlear implantation is an effective approach for adult patients with severe to profound sensorineural hearing loss. This study describes the outcomes of patients with substantial residual hearing who have undergone cochlear implantation. All 12 patients ultimately surpassed their preoperative aided performance level after implantation and gained significant benefit from their cochlear implant, although progress was slow for many patients. Six months after implantation, scores were 93%, 78%, and 48% on three tests in the implant ear alone.

Previous research suggests that children with pure-tone averages of greater than 90 dB hearing level and/or open-set sentence perception of less than 30% may gain significant benefit from cochlear implantation. In this study 16 children who obtained 30% or greater on preimplant open-set sentence material were selected to participate. Preimplant pure-tone averages ranged from 73 to 110 dB in the better aided ear. Fourteen of 16 subjects had improved speech perception scores across all test materials after implantation. The results of this study suggest that, with appropriate counseling and management, some children with significant residual hearing benefit from cochlear implantation.

Cochlear implants (CI) represent the current treatment for patients affected by profound sensorineural hearing loss (SNHL). Initially only deaf adult patients were considered to be candidates for a CI. In recent years, the criteria for cochlear implantation in children and adults have expanded. A number of patients who do not completely fulfill the current criteria are still potential candidates for CI. The duration of deafness and residual hearing affect the success of cochlear implantation. Cochlear ossification, cochlear malformation and chronic otitis media are still reasons for some surgeons not to do cochlear implantation. The experience of CI surgeons and the use of auditory brainstem implants have changed the approach to these patients, who may still benefit from hearing rehabilitation. This paper reviews the results obtained in these groups of patients, who were not initially considered to be candidates for cochlear implantation.

Educational Programs

This study examined the relationship between the teaching method, oral (focus on development of spoken language) or total communication (focus on both signed and spoken language), and children’s consonant-production accuracy and vocabulary development over time. The 147 children who participated in the study had profound sensorineural hearing loss and used cochlear implants between 6 months and 10 years. As they used their implants the children showed improved consonant-production accuracy and expressive and receptive vocabulary over time, regardless of which teaching method was used. Other considerations, such as the age at which children receive implants, may be more important than the educational program used. Ensuring that children receive the devices as early as possible, with the newest technology and in such a way as to achieve a complete active electrode array, offers the best opportunity for success in terms of speech and vocabulary, regardless of school program. Many factors including rehabilitation can affect children’s long-term outcomes.

This study consisted of a review of 83 implanted patients and their parents. Of the 30 children who were in nonmainstream school programs at implantation, 50% moved toward mainstream, with 30% reaching mainstream placement. Of the 34 children who were preschool at implantation, 70% were placed or planned to be placed in mainstream after implantation. The rate of improvement in speech perception ability was significantly higher in the children who moved toward or remained in mainstream than those who stayed at the same nonmainstream educational placement or moved away from mainstream. Children from a multilingual background had similar educational placements and similar rates of progress of speech perception as the only English-speaking children. In this study it was shown that children with cochlear implants have increased educational opportunities, with those children in mainstream and those who moved toward mainstream showing improved progress in speech perception ability.

Geers A, Spehar B, Sedey A. “Use of speech by children from total communication programs who wear cochlear implants.” American Journal of Speech-Language Pathology. 11(1): 50-8, 2002.

The study examined whether 27 eight and nine year-olds who had received a Nucleus 22-channel cochlear implant before age 5 acquire usable speech or continue to rely primarily on manual communication when they are enrolled in a total communication setting. Results showed a wide range of preferences, with some children using primarily speech, some primarily sign, and some using both modes to varying extents. Speech users achieved higher auditory speech perception scores and speech intelligibility ratings, and showed better understanding and use of English syntax than children who used little or no speech. After three years with an implant, speech users were more likely than children who used little or no speech to be placed in mainstream educational programs.

The study included 147 children with profound sensorineural hearing loss who had used cochlear implants for between 6 months and 10 years. It compared educational programs that used an oral communication (OC) approach focused on the development of spoken language and educational programs that used a total communication (TC) approach focused on the development of language using both signed and spoken language. Both teaching methods showed improved consonant-production accuracy and expressive and receptive vocabulary over time. There was no significant difference between the programs if the children received their implants during middle elementary school. Children who received their implants during preschool showed stronger performance, on average, on all measures over time than those who received their implants during their elementary school years. Results suggest that children can benefit from using cochlear implants regardless of the teaching approach used by their school program. The age at which children receive implants is an important element in their improvement in language development.

Language Development/Literacy (reading and writing)

Bergeson TR, Pisoni DB, Davis RAO. “A longitudinal study of audiovisual speech perception by children with hearing loss who have cochlear implants.” Volta Review. 103(4):347-70, 2003.

Results from the Pediatric Speech Intelligibility test of spoken word and sentence recognition skills from a large group of young children who are prelingually deaf and received cochlear implants were examined. The study ran from pre-implantation to 3 years post-implantation. Better performance was seen in the audiovisual presentation condition compared with auditory-alone and visual –alone conditions. Performance in all three conditions improved over time following implantation. Children from oral communication (OC) education backgrounds performed better overall than children from total communication (TC) backgrounds. Children in the early implanted group performed better than children in the late-implanted group in the auditory-alone condition after two years of cochlear implant use. Children in the late-implanted group performed better than children in the early-implanted group in the visual-alone condition.

This study examined whether age at cochlear implantation or duration of implant use is associated with speech, language, and reading skills at age 8 to 9 years in 181 children who received cochlear implants by age 5. Speech perception, speech production, language, and reading were examined in terms of the age at which children first received a cochlear implant (2, 3, or 4 years), the age they received an updated (Spectra) processor, and the length of time the implant was used with an updated processor. Earlier use of an updated processor (Spectra) was associated with greater speech intelligibility but not with any other skill area. More of the children who underwent implantation at age 2 years (43%) developed speech and language skills equal to children of the same age who had normal hearing than did children who underwent implantation at age 4 years (16%). Normal speech and language skills were documented in 80% of children who lost hearing after birth and who had implantation within a year of onset of deafness.

This study investigated factors contributing to the understanding and production of English language by 181 children with prelingual deafness after four to seven years of multichannel cochlear implant use. More than half the children showed language skills similar to those of hearing 8 to 9 year olds on measures of verbal reasoning, narrative ability, utterance length and word diversity. Age at receiving an implant did not affect language outcome. The primary rehabilitative factors associated with language outcome were amount of mainstream class placement and an educational emphasis on speech and auditory skills. The use of a chochlear implant had a dramatic impact on the language skills of profoundly hearing-impaired children. The mature language outcomes that were found were not typical of children with hearing loss who used hearing aids. An oral educational focus provided a significant advantage for both spoken and total language skills.

Word reading and comprehension levels of children who were implanted by age 5 were studied. One hundred eighty one children between 8 years and 9 years 11 months of age who had four to six years of implant experience were evaluated. Over half the children scored within the average range for their age. Reading competence was associated with mainstream educational placement, use of an updated implant speech processor with a wide dynamic range, longer memory span, later onset of deafness (between birth and 36 months), and use of phonological coding strategies.

This study examined the effects of age at implantation on the development of communication abilities in early implanted children. The 73 children in the study were prelingually deaf, received a cochlear implant before the age of 5, and used current cochlear implant technology. Results revealed significant improvements in communication skills over time. Spoken word recognition improved at a faster rate in children implanted at 5 years of age or older. The rate of spoken word development was significantly greater for children who used Oral Communication than for children who used Total Communication. Earlier implanted children demonstrated superior language abilities, with children implanted prior to 2 years of age having significantly faster rates of vocabulary and language development than later-implanted children. Children implanted prior to age 2 also had superior expressive language abilities.

Oral language skills in the first and second language were evaluated in 12 prelingually deaf bilingual children between the ages of 20 months and 15 years who received a cochlear implant before the age of 3 years. Skills were measured a two yearly intervals after implantation. Average standard scores in the first language were solidly within the average range of normal-hearing peers. Second-language skills showed steady improvement from year 1 to year 2, according to the amount and intensity of exposure of the child to the second language and the length of experience with the implant. It was found that a cochlear implant can make oral skills in more than one language possible for prelingually deaf children.

The language and literacy (reading and writing) skills of 16 children with cochlear implants were compared with those of 16 normal-hearing children of the same age. The results of the study suggest that the language skills of pediatric cochlear implant users are related to and correlated with the development of literacy skills within these children, and compared favorably to the group of children with normal hearing on measures of language comprehension, reading comprehension and writing accuracy. However, they produced fewer words on the written narrative task. There were also significant differences in the ability of the cochlear implant users to correctly use grammatical structures in written and oral sentences, and it is suggested that this should be emphasized in educational or remedial language programs.

Language development and speech perception outcomes in children who received cochlear implants in the 2^nd, 3^rd and 4^th year of life were compared. It was found that implantation before the age of 2 resulted in significantly better speech perception and language skills. These results are consistent with the existence of a 'sensitive period' for language development, with a gradual decline in language acquisition skills as a function of age.

Analysis was conducted of the speech intelligibility of children with profound prelingual hearing impairment who received cochlear implants before the age of 6 and who had used a state-of-the-art stimulation strategy (SPEAK or CIS) since initial stimulation. They were compared with children using hearing aids. In the hearing aid group, intelligibility is highly correlated with age of testing, suggesting that many profoundly deaf hearing aid users become more intelligible over time, even without a CI, possibly as result of greater maturity and oral training. However the differences in speech intelligibility with implant use clearly exceed the changes over time predicted for profoundly deaf hearing aid users.

This study sought to determine whether cochlear implants facilitate the development of English language skills. The English language skills of 44 prelingually deaf children with cochlear implants were measured before and after implantation. It was found that the rate of language development after implantation exceeded that expected from unimplanted deaf children and was similar to that of children with normal hearing. The best performers in the implanted group seem to be developing an oral linguistic system based largely on hearing input from a cochlear implant.

Waltzman SB, Robbins AM, Green JE, Cohen NL. “Second oral language capabilities in children with cochlear implants.” Otology & Neurotology. 24(5):757-63, 2003.

The purpose of this research was to explore 1) the feasibility of children with cochlear implants developing oral fluency in a second language and 2) the factors that affect that development. Eighteen profoundly hearing-impaired children who were reported to be bilingual and who had cochlear implantation at age 5 or younger were included in the study. Results showed the ability of some children with cochlear implant to develop skill in a second spoken language in addition to their primary language. Equally as important is the fact that the majority showed age-appropriate language abilities in their primary language equal to that of normal-hearing children. High levels of achievement including the learning of a second spoken language are possible after implantation in children. Factors affecting the outcome include speech perception post-implantation, the linguistic environment, type of intervention, and educational placement.

Watson L. “The literacy development of children with cochlear implants at age seven.” Deafness & Education International. 4(2):84-98, 2002.

This study investigated the literacy development at age 7 and older of a group of deaf children who received cochlear implants prior to age 5. Seven out of the 10 children investigated were achieving literacy levels that reached or approached the standard expected for all children of their age in some aspects of literacy, and the same children were beginning to use phonic strategies.

Music Perception

This study compared the effect of structured training on recognition and appraisal of the timbre (tone quality) of musical instruments by postlingually deafened cochlear implant recipients. Twenty-four implant users (Nucleus CI24M) were randomly assigned to a control or a training group. The control group experienced only casual exposure to music in their usual daily routine. The training group received 12 weeks of training on a laptop computer introducing them to excerpts of musical instruments representing three frequency ranges and four instrumental families. The implant recipients in the training group showed significant improvement in timbre recognition and timbre appraisal compared to the control group.

Gfeller K, Mehr M, Witt S. “Aural rehabilitation of music perception and enjoyment of adult cochlear implant users.” Journal of the Academy of Rehabilitative Audiology. 34:11-16, 2001.

A review of the research on music perception in chochlear implant users is presented. Although structured instructional listening tasks have resulted in significant improvements in listening perception, a number of beneficial music learning experiences can be found in everyday listening experiences as well. The author provides practical recommendations for improving music listening enjoyment for cochlear implant recipients based on the results of field trials that are outlined in this paper. Structural features of music most responsive to rehabilitation are discussed.

This study compared the ability of normal-hearing and cochlear implant listeners to use temporal cues in three music perception tasks: tempo discrimination, rhythmic pattern identification and melody identification. The results indicate that the cochlear implant provides sufficient spectral cues to support speech recognition in quiet, but they are not adequate to support music perception. Increasing the number of functional channels and improved encoding of fine structure information are necessary to improve music perception for cochlear implant listeners.

Psychological/Social Issues

This study sought to increase knowledge about the stressors affecting families of children with cochlear implants and about factors that help families to cope. It looked at the process of implantation and the long training period that follows. The results suggest that support from the cochlear implant team and school staff in terms of advice and practical help were important factors. A high level of social support was associated with lower stress ratings and better outcomes, helping parents to cope, decrease stress and better the quality of life of families dealing with the implant assessment process, hospitalization, tuning sessions and ongoing rehabilitation and training. The importance of realistic parental expectations was stressed. It was also recommended that support for siblings be provided to help them feel important and of value to the cochlear implant wearer. Overall parents who participated in the study seemed pleased with their child’s progress.

These studies examined changing parent and deaf community perspectives related to pediatric cochlear implantation. While parents frequently receive conflicting information about educational and communication options for their child, they generally support signing before and after implantation. The parents of a child with an implant have a great interest in their child's spoken language development, and most would like to have had their child receive an implant earlier. Children with implants are educated in a variety of educational settings. Mainstreamed children with implants often continue to require classroom support services, and children with implants are frequently not isolated from both deaf and hearing peers. Opposition to cochlear implantation in children within the deaf community is giving way to the view that it is one of a number of possibilities for parents to consider. To ensure optimal use of the cochlear implant, parents need to remain involved in their child's social and educational development.

The quality-of-life (QOL) benefit received from cochlear implants and hearing aids among hearing-impaired adults was studied. Twenty-seven cochlear implant users were compared to a control group of 54 hearing aid users, both groups older than 49. Compared to hearing aid patients, cochlear implant users showed twice as much overall improvement in their quality of life as those with hearing aids. These benefits were seen in cochlear implant users rather than hearing aid users in the physical, psychological, and social areas. Cochlear implants provide at least similar benefit for those with profound hearing loss as hearing aids bring for those with less severe hearing loss.

Heydebrand G, Mauze E, Tye-Murray N, et al. "The efficacy of a structured group therapy intervention in improving communication and coping skills for adult cochlear implant recipients." International Journal of Audiology. 44(5):272-80, 2005 May.

This paper reports on an evaluation of a structured group therapy intervention for adult cochlear implant (CI) recipients designed to improve overall communication and coping skills. 33 adult CI recipients participated in a 2-day structured group therapy intervention with a follow-up session 4 weeks later. Participants demonstrated significant improvements on measures of assertiveness, emotional well-being, and coping behaviors at 3 months post-intervention that persisted at a 12-month follow-up. Although subjects had presumably adapted to their cochlear implants and had learned communication strategies in hearing rehabilitation programs, the improvements on several measures suggest that a structured group therapy intervention is another way to enhance outcomes following cochlear implantation.

Twenty four children between age 2 and 13 years who had received Nucleus multichannel cochlear implants were studied. Most attended mainstream schools in their communities, usually with the aid of sign language interpreters. No evidence of negative psychological consequences of cochlear implantation was found. The study suggests that the hearing benefits of cochlear implantation may lead to greatly improved cognitive abilities and that implants produce no ill effects on psychological well-being. However, children who show pre-implant behavior problems (such as aggression, destructive behavior and attention problems) may realize less benefit from a cochlear implant.

The psychological and social adjustment of 181 school-aged deaf children who have had cochlear implants for 4 or more years was studied. It examined parents’ satisfaction with the outcome of the implantation process on their child’s life and on family life. Deaf children who have used a cochlear implant for 4 to 6 years report they are coping successfully with the demands of their social and school environment, regardless of their speech and language achievements after implantation. Parents’ ratings indicate that these children are emotionally and socially well adjusted and that they have benefited from cochlear implantation in terms of speech and language achievements. These results represent an impressive level of personal and social adjustment when compared with previous literature on adjustment problems in deaf children.

Speech Intelligibility

The connected speech intelligibility of children who use cochlear implants was compared with that of children who have normal hearing. Results showed that for children with cochlear implants, greater intelligibility was related to both older age and increased length of time of cochlear implant use. Children with normal hearing achieved adult-like intelligibility around the age of 4 years, but a similar peak was not observed for children who used cochlear implants. These results have implications for the socialization and education of children with cochlear implants, particularly with respect to placement in mainstream educational environments with age peers.

Results of studies performed at Washington University School of Medicine suggest that cochlear implant recipients understand speech best if the following speech processor parameters are individually chosen for each person: MAP, stimulation rate, and speech coding strategy. If these and related parameters are chosen to make soft sounds (from approximately 100 to 6,000 HX) audible at as close to 20 dB hearing level as possible and loud sounds not too loud, recipients have the opportunity to hear speech in everyday life situations that are of key importance to children who are learning language and to all recipients in terms of communication.

One hundred eighty-one cochlear implant users and 24 children with normal hearing engaged in spoken conversations with a clinician. Conversations were audiotaped and videotaped in order to analyze the children’s speech intelligibility, length utterance and speech recognition. The cochlear implant users spent significantly more time in communication breakdown and in silence than the children with normal hearing. Children who are in an educational placement that emphasizes oral communication performed better than children who are in a placement that uses both speech and sign. The results show a need for communication therapy and suggest that educational programs should provide instruction to promote conversational fluency.

This study compared acoustic characteristics of speech of 181 young children who use cochlear implants with those of 24 children with normal hearing. It also examined the effect of the deaf child’s education (oral vs. total communication) on these hearing measures. A large percentage (46-97%) of the cochlear implant users produced acoustic characteristics with values within the range found for children with normal hearing. Exceptions were sentence duration and vowel duration in sentence-initial words, with only 23-25% of chochlear implant users having values within the normal range. Significantly more cochlear implant users from oral rather than from total communication settings had values with the normal range. Compared with deaf children with hearing aids from previous studies, deaf children who use cochlear implants have improved speech production skills. Placement in an oral communication educational setting rather than a total communication setting is also associated with more speech production improvement.

Speech Perception

Advantages were found using cochlear implants with hearing aids in the opposite ear. On average, there were significant benefits in speech perception, localization and aural/oral function when the children tested used cochlear implants with adjusted hearing aids over the use of cochlear implants alone. All showed benefits in at least one of the measures selected. Adjustment of hearing aid gain to match loudness in the implanted ear can facilitate integration of signals from both ears, leading to better speech perception.

Factors contributing to speech perception in children with prelingual deafness who received a cochlear implant by age 5 after 4 to 7 seven years of multichannel cochlear implant use were studied. The type and amount of educational intervention since implantation were studied. The children achieved an average level of about 50% open-set speech perception through listening alone and almost 80% through lip-reading and listening together. Significant predictors of good speech perception included greater nonverbal intelligence, smaller family size, long use of the updated SPEAK/CIS processing strategy, a fully active electrode array, greater electrical dynamic range between threshold and maximum comfort level, and greater growth of loudness with increasing stimulus intensity. The main aspect of rehabilitation associated with good speech perception skill development was educational emphasis on speech and hearing.

This study looked at the improvement in speech recognition provided by a cochlear implant in conjunction with a hearing aid in the opposite ear. Seven CI patients who still use their hearing aid in the opposite ear were tested. In the majority of tests and subjects, the cochlear implant alone performed better than the hearing aid alone, and the use of both devices was superior to the use of the cochlear implant alone. The results of this study suggest the advantage of cochlear implant use in conjunction with a hearing aid in the opposite hear.

Houston DM, Ying EA, Pisoni DB, Kirk KI. “Development of pre-word learning skills in infants with cochlear implants.“ Volta Review.” 103(4):303-26, 2003.

The effectiveness of early cochlear implantation through measurement of speech perception and language skills during infancy was evaluated. A component of language development is word learning – a complex skill that involves learning arbitrary relations between speech sounds and objects. Infants who received their cochlear implants at 7-15 months of age performed similarly to infants with normal hearing after about 2-6 months of cochlear implant experience. In contrast, infants who received their implants at a later age, between 16-25 months of age, did not demonstrate learning of the associations within the context of this study.

Ten children diagnosed with auditory neuropathy were matched with 10 children who had different causes of deafness. All 20 children received cochlear implants. Various measures were used to compare the outcomes for the two groups including performance on age- appropriate speech perception tests and parents’ report of cochlear implant benefit. The results of this study showed that there were no important differences in cochlear implant benefit between the two groups. Cochlear implants seem to be a realistic option for selected children with auditory neuropathy.

This study compared the functioning of 40 children with severe to profound hearing impairment between 1½ and 9 years of age who underwent cochlear implantation. Measurement were taken before and one year after surgery. Significant improvements were found one year after surgery in hearing, speech perception and overall developmental functioning. Greater benefits in hearing and developmental functioning were found in children who were younger than 48 months at implantation.

Pure-tone thresholds, word recognition and listening performance were studied before and after implantation in 67 adults. Three months after switch-on of the implant, the mean word recognition score was 54%. There was clear improvement in the mean word recognition scores over a longer period of time, with a mean score of 71% twenty-four months after switch-on. Six months after switch-on, 40 out of 48 adults were able to recognize some speech without speech-reading, and 26 of the 48 subjects were able to use the telephone with a known speaker, gaining good benefit from the implant.

Implantation in Very Young Children

This study evaluated outcomes of children implanted under the age of 2 and compared them to children implanted at a later age. Thirty-seven children enrolled in the study who received cochlear implants before the age of 2 were evaluated using various tests and questionnaires before surgery, at initial fitting, 1, 3, 6 and 12 months after first fitting, and then each year thereafter. The children's scores improved significantly over time. Improvement was shown to occur at a quicker rate for children implanted at an earlier age than for children implanted at an older age on some tests. Results suggest the distinct advantage early implantation may have for severe to profoundly hearing impaired children. This may be particularly the case for skills necessary for development of receptive and expressive language skills.

This review looks at the past 20 years in which cochlear implants have evolved from an innovative but radical concept to the standard of care in the management of children with severe to profound hearing loss. All children receiving the cochlear implant achieved substantial benefit. Performance gains are enhanced by a team of audiologists, speech pathologists and surgeons with specific expertise in the management of children with cochlear implants and is critical to maximizing the benefit the child received.

Colletti V, Carner M, Miorelli V, et al. "Cochlear implantation at under 12 months: report on 10 patients." Laryngoscope. 115(3): 445-9, 2005

The age of cochlear implantation has substantially decreased over the years. This study reports on cochlear implantation in ten very young children, between 4 and 6 months of age. Hearing performance increased as a function of early age of implantation and length of implant use. The onset of babbling occurred very early, within 1 to 3 months of activation of the implant. Using CAP scores, which measured postoperative auditory performance, all 10 children had a score of 3 within 6 months of cochlear implant activation. In this study very early implantation facilitated a series of developmental processes that occur in the critical period of initial language acquisition.

Early identification of congenitally deaf children as candidates for cochlear implantation is leading to surgery in younger children. The safety of cochlear implantation in children aged 12 months and younger is reviewed. Twenty-five infants received implants at 7 to 12 months of age because of meningitis (4 children) or early detection of deafness (21 children). Cochlear implant surgery was found to be safe in children aged 7 to 12 months with appropriate anesthetic and post-operative support.

The onset of pre-speech babbling and the outcomes of 10 deaf children who received a cochlear implant (CI) before the age of 20 months were studied. Ten congenitally deaf infants implanted at an age between 6 and 18 months were included in the study. All children received a Nucleus-24 multichannel cochlear implant. All children started babbling after a short interval of 1 to 4 months after activation of the device so that the onset of babbling in the youngest subjects occurred at an age comparable to that of normally hearing infants. The earlier the implantation, the closer the results approached the outcomes of normally hearing infants. The earlier the implantation took place, the smaller the delay was in comparison with normally hearing children with regard to the onset of pre-speech babbling and auditory performance.

Implantation in the Elderly

The benefit of cochlear implantation in adults aged 60 years and over was evaluated. Twenty-eight patients, older than 60 years and with profound bilateral sensorineural hearing loss, received a cochlear implant between 1991 and 2001. Speech perception scores before and after implantation were analyzed. There was a significant improvement of the disyllabic words and sentences scores after implantation. The patients who were over 70 years performed as well as those who were younger. The surgical procedure was well tolerated in all patients. Cochlear implantation offered improvement in speech perception to the elderly population, as in the younger population.

The effectiveness, quality of life and complication rate of cochlear implantation in 31 patients over 60 years of age were assessed. All patients had improvement in their hearing test results after operation. Twenty-eight (93%) were regular implant users at a median follow-up of 12 months. Major complications occurred in two patients (6%). Cochlear implantation in the elderly appears to have excellent results, with a complication rate similar to that in patients less than 60 years old, and leads to an improved quality of life.

Cholesteatomas

Cholesteatomas are benign tumors that develop in the middle ear. They grow rapidly and over time can result in hearing loss, pain, or neuropathies. Because of this it is important to identify cholesteatomas early and treat them promptly. There are two types of cholesteatomas: congenital middle ear cholesteatoma is less common than the acquired cholesteatoma.

Overview
Kazahaya K, Potsic WP. “Congenital cholesteatoma.”Current Opinion in Otolaryngology & Head & Neck Surgery.12(5):398-403, 2004.
In the past congenital cholesteatomas were considered to be a rare disorder. However, a review of the literature reveals an incidence ranging from 4 to 24%, and these values are probably underestimated. Conductive hearing loss is the most common presenting symptom. Treatment of congenital cholesteatomas is still surgical. Preoperative computed tomography should be considered to assist in preoperative planning and prediction of postoperative issues. Increased awareness and early diagnosis of congenital cholesteatomas is crucial. Early treatment decreases the extent of the disease and reduces the risk of relapse and complications

Rash EM. “Recognize cholesteatomas early.” Nurse Practitioner. 29(2):24-9, 2004.
Cholesteatomas are benign tumors that develop in the middle ear, and their rapid growth patterns can impinge on local structures, resulting in hearing loss, pain, or neuropathies. These late signs and symptoms can be avoided by early identification and prompt intervention. Primary care providers should be aware of the incidence, prevalence, identification, and associated symptoms of cholesteatomas to reduce the later untoward affects and promote prompt referral.

Pediatric Cholesteatoma
Overview
Edelstein DR, Parisier SC, Ahuja GS, Juarbe C, Chute P, Wenig S, Kaye SM. “Cholesteatoma in the pediatric age group”. The Annals of Otology, Rhinology & Laryngology. 97(1):23-9, 1988
The diagnosis and management of cholesteatoma in children remains controversial. In the past 15 years, the senior author (S.C.P.) has treated 320 patients with cholesteatoma. Patients 18 years and younger composed 40% (125) of the overall group and are the basis for this report. The surgical treatment selected was determined by the extent of disease, the configuration of the mastoid, and a clinical assessment of eustachian tube function. A middle ear tympanotomy approach was used in 17% of the patients, a canal wall up procedure in 31%, and a canal wall down procedure in 52.3%. The average clinical follow-up was 3.9 years, with the range being from 3 months to 13.5 years. Hearing was maintained or slightly improved in a majority of cases. Residual disease occurred in 8% of patients, and recurrent disease in only 3%. Potsic

Potsic WP,Korman SB,Samadi DS, Wetmore RF.“Congenital cholesteatoma: 20 years' experience at The Children's Hospital of Philadelphia.” Otolaryngology--Head & Neck Surgery. 126(4):409-14,2002
The experience of The Children’s Hospital of Philadelphia with congenital cholesteatoma over a span of 20 years is reported, with an emphasis on presenting signs and predictors of outcome. One hundred seventy-two congenital cases were identified in 167 patients. Five patients had bilateral disease. The majority (72%) were found in boys, with an average age of 5 years. Hearing loss was slight to moderate. When confined to 1 quadrant, cholesteatoma was located anterosuperior in 82% of cases; 47% had cholesteatoma in 2 or more quadrants. Ossicular chain involvement was found in 43% of all cases, and mastoid extension was evident in 23%. The rate of recurrent disease was directly related to the extent and number of quadrants involved.

Shohet JA, de Jong AL.“The management of pediatric cholesteatoma.” Otolaryngologic Clinics of North America. 35(4):841-51, 2002.
Pediatric cholesteatoma can be congenital or acquired. The two types appear to be separate and distinct entities. Pediatric cholesteatoma behaves differently from cholesteatomas in the adult. This may have more to do with anatomic and physiologic differences than with the molecular structure of the cholesteatoma. Treatment requires an individualized approach taking into account the experience of the operative surgeon and the high risk of recurrence of this disease.

Grundfast KM, Ahuja GS, Parisier SC, Culver SM. “Delayed diagnosis and fate of congenital cholesteatoma (keratoma).” Archives of Otolaryngology-- Head & Neck Surgery. 121(8):903-7, 1995
This case study analyzed clinical presentation, modes of detection, growth pattern, operative findings, and results of surgery in children 3 years old or older who had extensive congenital cholesteatoma (keratoma) at two medical centers. Twenty-five children who received tympanomastoid surgery, ie, canal wall up and canal wall down, some with ossicular reconstructive surgery, were selected. Audiologic assessment (speech reception threshold) and recurrence of cholesteatoma were documented. The incidence of recurrence was 52%. Hearing was maintained within the range of normal to mild hearing impairment postoperatively in 91% of the patients for whom complete data are available. Congenital cholesteatoma may grow for years without causing signs or symptoms and, having grown without early detection, can extend to involve the epitympanum and mastoid antrum, cause ossicular erosion, and even extend to the middle cranial fossa.

Surgery
Fageeh NA, Schloss MD,Elahi MM, et al.“Surgical treatment of cholesteatoma in children.”Journal of Otolaryngology. 28(6):309-12, 1999
The medical charts of 173 patients surgically treated for cholesteatoma were reviewed over a 15-year period to determine the impact of surgical procedures on preoperative hearing status and whether there was preservation, improvement, or deterioration. One hundred eighteen (68%) patients had acquired cholesteatoma and 55 (32%) patients had congenital cholesteatoma. One hundred (58%) patients had extensive disease on presentation that required canal wall-down mastoidectomy. Patients with attic cholesteatoma underwent canal wall-up mastoidectomy, and those with cholesteatoma localized to the middle-ear space were adequately treated with tympanotomy. Hearing was preserved in 101 cases (59%), improved in 30 (17%), became worse in 23 (13%), and could not be accurately assessed in 19 (11%) due to lack of documentation. A second surgical procedure for recurrent or residual disease was required in 53 (30%). This study confirmed the aggressiveness of cholesteatoma in children and demonstrated the need for careful preoperative evaluation, meticulous surgical technique, and good postoperative follow-up.

Iino Y, Nagamine H, Sasaki Y, Kodera K. “Hearing results of canal wall reconstruction tympanoplasty for middle ear cholesteatoma in children.” International Journal of Pediatric Otorhinolaryngology.60(1):65-72, 2001.
Post-operative hearing results in children with middle ear cholesteatoma were evaluated. One hundred and twenty-three children who were operated on for middle ear cholesteatoma at the age of 10 years or younger by canal wall reconstruction tympanoplasty were followed up more than 1 year after the final operation. The average pre-operative and post-operative hearing were investigated. The mean of the average air conduction hearing level of 124 ears was significantly improved from 34.7 to 27.1 dB after the final operation. Among them, 84 ears (67.8%) showed a hearing level of 30 dB or less post-operatively. Significant improvement in post-operative hearing was noted in ears with normal middle ear mucosa or middle ear effusion at the final operation. Children with middle ear cholesteatoma at the age of 10 years or younger showed good hearing post-operatively. Canal wall reconstruction tympanoplasty for pediatric cholesteatoma was successful in terms of hearing results

Parisier SC, Hanson MB, Han JC, Cohen AJ, Selkin BA. “Pediatric cholesteatoma: an individualized, single-stage approach.” Otolaryngology--Head & Neck Surgery.115(1):107-14, 1996
The outcomes of a one-stage surgery for pediatric cholesteatoma in 216 ears are reported. The technique is based on three main principles: (1) the surgery is individualized; (2) the goal of surgery is to completely remove cholesteatoma and related disease in one operation; and (3) the reconstruction is performed to provide both good hearing and a dry, trouble-free ear. The incidence of recurrence was 10.2%, and the rate achieved was 13.3% at 5 years and 24% at 10 years. Canal wall down surgery was the predominant procedure used. The incidence of intraoperative neurosensory hearing loss, vertigo, and facial nerve injury was extremely low. The postoperative cavity problems encountered were minimal

Soldati D, Mudry A. “Cholesteatoma in children: techniques and results.” International Journal of Pediatric Otorhinolaryngology.52(3):269-76, 2000.
An analysis of the medical records of all cases of cholesteatoma in children treated between 1981 and 1996 at one hospital was performed. A total of 62 ears received surgery over 15 years with a median follow-up period of 5 years. There were 132 operations. An intact canal wall (ICW) procedure was performed in 29% of the ears in the first stage, a canal wall down (CWD) procedure in 37%, a transmeatal atticotomy (TA) in 21%, a tympanoplasty (T) in 6.5% and a myringoplasty (M) in 6.5% of the ears. The ICW procedure had a higher rate of residual/recurrent cholesteatoma than did CWD, TA, T, and M procedures. The CWD procedure had a lower rate than TA, but a higher rate than T and M. TA had a higher rate than T and M. An air-bone gap of less than 20 dB was achieved in 51% of the ears, and 80% had a gap of less than 40 dB. A clear difference in the rate of recurrent cholesteatoma based on the experience of the surgeons was found: 26% for surgeons who had performed more than 350 otological surgeries, 15% for the most-experienced surgeon (1715 operations), 34% for the less experienced surgeons.

Silvola J, Palva T. “Long-term results of pediatric primary one-stage cholesteatoma surgery.” International Journal of Pediatric Otorhinolaryngology.48(2):101-
The long-term results of surgical treatment for pediatric cholesteatoma vary and there is no agreement on operation methods and on factors affecting outcome of surgery. The long-term results and possible reasons for recurrence of cholesteatoma were investigated. A total of 84 pediatric cholesteatoma operations at one hospital were reviewed. The total recurrence rate was 29% (24/84), and it was not dependent on the size of cholesteatoma, mastoid status, cholesteatoma in the window niches or stapedial erosion. A retraction process developed in 25% (21/84) of the ears and 42% (9/21) of these turned into retraction pocket cholesteatomas as late as 13 years postoperatively. Retractions and postoperative discharge, especially in combination, predisposed to recurrence of the cholesteatoma. Hearing was maintained on the preoperative level.

Syms MJ, Luxford WM. “Management of cholesteatoma: status of the canal wall.” Laryngoscope. 113(3):443-8, 2003.
The factors associated with the surgical approach to manage cholesteatoma were examined. A review of medical charts was made of all cases of mastoid surgery for cholesteatoma performed at an otological center between 1995 and 2000. During the study period, 486 ears underwent surgery for cholesteatoma. Data included procedures performed, location and extent of the disease, residual and recurrent disease, complications, reasons for staging the surgery, and duration of follow-up. The canal wall remained intact in 68.5% of ears. The majority of the remainder of the patients underwent a canal wall down technique with mastoid obliteration. Residual cholesteatoma was found in 26.9% of second procedures and in 2.7% of third procedures. It was found that the majority of patients with cholesteatoma were adequately managed with a canal intact tympanomastoidectomy with staging. It is recommended that otolaryngologists consider a two-staged procedure as a viable management approach for chronic otitis media with cholesteatoma.

Recurrence
Ahn SH, Oh SH, Chang SO, Kim CS. “Prognostic factors of recidivism in pediatric cholesteatoma surgery.” International Journal of Pediatric Otorhinolaryngology. 67(12):1325-30, 2003
Review of the medical charts of 118 children with acquired cholesteatoma who underwent surgery from January 1978 to October 1999 was conducted. The median observation period was 5 years, range 1-20 years. Cholesteatoma in patients less than 8 years old with mastoid involvement had significantly higher risk of recurrence than the other groups examined. In this study, cholesteatoma recurred up to 5 years after operation. Long-term close follow-up is important especially in cases involving higher risk such as the younger child with mastoid extension of cholesteatoma

Parisier SC, Weiss MH. “Recidivism in congenital cholesteatoma surgery.” Ear, Nose, & Throat Journal. 70(6):362-4, 1991.
In this report forty-four cases of congenital cholesteatoma in the pediatric age group have been treated surgically. There have been three residual cholesteatomas, which were localized to the anterior aspect of the malleus and were easily excised. Two cases of postero-superior retraction pockets developed post-operatively, and these were treated by conventional tympanomastoid surgery with excision of the retraction pocket and grafting. All five of the patients with recurrence have experienced no further difficulty.

Roger G, Denoyelle F, Chauvin P, et al. “Predictive risk factors of residual cholesteatoma in children: a study of 256 cases.” American Journal of Otology. 18(5):550-8, 1997
This study aimed to determine which children are at risk of having residual cholesteatoma develop after initial surgery for either cholesteatoma or severe retraction pocket. Mean follow-up period was 42 months. Two hundred thirty-one children (256 ears) with either cholesteatoma (n = 157) or severe retraction pockets (n = 99), both treated surgically, composed the patient group. Posterior mesotympanum involvement, ossicular chain interruption after disease excision (and moreover combination of both), relative lack of experience of the surgeon, and presumed incomplete removal were identified as independent risk factors highly correlated with residual development. The identification of any of these factors should mandate a second-look procedure regardless of other initial surgical findings and of the surgical technique used.

Stangerup SE, Drozdziewicz D, Tos M. “Cholesteatoma in children, predictors and calculation of recurrence rates.” International Journal of Pediatric Otorhinolaryngology. 49 Suppl 1:S69-73, 1999
The aim of the study was to evaluate the long-term recurrence rate after surgery for acquired cholesteatoma in children and to search for predictors of recurrency. During a 15-year period, 114 children underwent first-time surgery for acquired cholesteatoma. The patients were re-evaluated with a median observation time of 5.8 years, range 1-16 years. Recurrence of cholesteatoma developed in 27 ears. Young children with poor Eustachian tube function, large cholesteatoma and erosion of the ossicular chain are at special risk of recurrence and should be observed several years after surgery

Weiss MH, Parisier SC, Han JC, Edelstein DR. “Surgery for recurrent and residual cholesteatoma”. Laryngoscope. 102(2):145-51, 1992.
One hundred twelve patients (116 ears) were treated for recurrent and residual cholesteatoma. A retrospective review revealed that 66% had undergone canal wall down mastoidectomy at the previous surgery. The surgical procedure at revision was selected on the basis of an intraoperative assessment of the extent of disease, and clinical prediction of eustachian tube function. The average period of follow-up was 3.4 years. Revision surgery was successful in providing the patient with a safe, dry ear in 105 (91%) of 116 cases. Surgical principles and hearing results are presented.

Adult cholesteatoma
Nomura K, Iino Y, Hashimoto H, et al. “Hearing results after tympanoplasty in elderly patients with middle ear cholesteatoma.” Acta Oto-Laryngologica. 121(8):919-24, 2001
The effect of aging on hearing results after canal wall reconstruction tympanoplasty was assessed in 213 patients with middle ear cholesteatoma. The elderly group (n = 34), defined as patients 60 years or older, was compared to the younger groups in terms of postoperative hearing level, hearing gain, A-B gap and change in bone conduction hearing level at 4000 Hz. Postoperative hearing level and hearing gain were found to be better amongst patients aged 20-29 and 30-39 years than in the elderly group, while A-B gap did not differ between all age categories. Within the elderly group, air conduction hearing level improved after surgery. Changes in bone conduction hearing level at 4000 Hz were not significantly different between the age groups. It is concluded that surgeons should be encouraged to perform tympanoplasty aimed not only at removing the lesion itself but also at improving hearing acuity in the elderly

Labyrinthine fistulas and cholesteatomas
Parisier SC, Edelstein DR, Han JC, Weiss MH. “Management of labyrinthine fistulas caused by cholesteatoma”. Otolaryngology--Head & Neck Surgery. 104(1):110-5, 1991
The surgical management of labyrinthine fistulas caused by cholesteatoma remains controversial. Forty cases (41 ears) of labyrinthine fistulas were reviewed. This represented 10% of the total series of cholesteatomas in adults and children (426 ears). Clinical presentation, extent of disease, results of fistula testing, audiometric studies, and radiographic findings were analyzed. A canal wall-down procedure was performed in all but one patient. Generally an attempt was made to completely remove the cholesteatoma, to graft the fistulous area, and to reconstruct the middle ear mechanism in one stage. The matrix was preserved in patients with large fistulas where the involved ear was the only hearing one, when the matrix was adherent to the underlying optic duct, and in selected elderly persons. Long-term follow up did not reveal a significant difference in hearing, degree of vertigo, or incidence of recurrence when those patients in whom the matrix was removed were compared with those in whom the matrix was preserved. The importance of recognizing the presence of a labyrinthine fistula preoperatively is stressed, along with the need to be prepared for an unexpected fistula

Cellular Biology of Cholesteatomas
Albino AP, Reed JA, Bogdany JK, Sassoon J, Desloge RB, Parisier SC. “Expression of p53 protein in human middle ear cholesteatomas: pathogenetic implications.” American Journal of Otology. 19(1):30-6, 1998.

Albino AP, Reed JA, Bogdany JK, Sassoon J, Parisier SC. “Increased numbers of mast cells in human middle ear cholesteatomas: implications for treatment.” American Journal of Otology. 19(3):266-72, 1998.

Albino AP, Kimmelman CP, Parisier SC. Cholesteatoma: a molecular and cellular puzzle. American Journal of Otology. 19(1):7-19, 1998.

Desloge RB, Finstad CL, Sassoon J, Han JC, Parisier SC, Albino AP. “Altered regulation of cell surface peptidases in human cholesteatoma.” Otolaryngology-- Head & Neck Surgery. 116(1):58-63, 1997.

Desloge RB, Carew JF, Finstad CL, Steiner MG, Sassoon J, Levenson MJ, Staiano-Coico L, Parisier SC, Albino AP. “DNA analysis of human cholesteatomas.” American Journal of Otology. 18(2):155-9, 1997.

Frankel S, Berson S, Godwin T, Han JC, Parisier SC. “Differences in dendritic cells in congenital and acquired cholesteatomas.” Laryngoscope. 103(11 Pt 1):1214-7, 1993

Parisier, SC, Agresti, CJ, Frankel, S, Han, JC, Albino, AP: Localization of platelet-derived growth factor in cholesteatoma. Transactions of the American Otological Society. 189, 1992

Parisier SC, Agresti CJ, Schwartz GK, Han JC, Albino AP. “Alteration in cholesteatoma fibroblasts: induction of neoplastic-like phenotype.” American Journal of Otology. 14(2):126-30, 1993

Parisier, SC, Agresti, CJ, Schwartz, GK, Han, CJ, Albino, AP: Spontaneous induction of invasive potential in cholesteatoma fibroblasts. Cholesteatoma and Mastoid Surgery, 4:111, 1993

Hearing Loss in Children

This review looks at screening and prevention of hearing loss in children. Congenital hearing loss is the most common neurosensory handicap in newborns. Technology has become available that allows states to implement universal screening programs at a relatively low cost and with minimal expertise needed for hospital personnel to operate the screening machines. In successful programs, the age of diagnosis has been reduced from 2(1/2) years to 3 to 6 months. Children diagnosed with hearing loss before speech develops have been shown to have better speech and language outcomes than those who are diagnosed later. Strategies for screening and early intervention are discussed, as well as the causes, prevention, and treatment of more common forms of childhood hearing loss.

Noise-induced hearing loss (NIHL) among children is increasing. Experts have recommended implementation of hearing conservation education programs in schools. Despite these recommendations made over the past three decades, basic hearing conservation information that could prevent countless cases of NIHL is not available in most school curricula. This paper reviews existing hearing conservation education programs and materials designed for children or those that could be adapted for classroom use.

This paper reviews the current literature about the impact unilateral hearing loss (UHL) has on the development of speech and language and educational achievement. Problems in school include a 22% to 35% rate of repeating at least one grade, and 12% to 41% receiving additional educational assistance. Speech and language delays have been reported in some but not all studies. School-age children with UHL appear to have increased rates of grade failures, need for additional educational assistance, and behavioral issues in the classroom. Speech and language delays may occur in some children with UHL, but it is unclear if children "catch up" as they grow older.

The frequency of moderate-profound bilateral sensorineural hearing loss (SNHL) in children of both genetic and non-genetic causes were reviewed. Forty-three studies were included in this review. The common causes of bilateral SNHL were unknown causes (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 causes in the more recent studies, while genetic non-syndromic, asphyxia and prematurity were more common. Genetic non-syndromic hearing loss was more common among patients with profound hearing loss.

This article reviews research on the possible linkage of otitis media with effusion (OME) to children's hearing and development, identifies gaps and directions for research, and discusses implications for healthcare practices. About half of children with an episode of OME experience a mild hearing loss while about 5-10% of children have moderate hearing loss. Recent clinical trials suggest none to very small negative associations of OME to children's later language development. Associations between OME and perceiving speech in noise and tasks that require equal binaural hearing have been reported but have not been adequately studied. Thus, on average, for typically developing children, OME may not be a substantial risk factor for later speech and language development or academic achievement.

Hearing Aids and Other Technology

Children’s classrooms have background noise and reverberation that interfere with accurate speech perception. Amplification technology can enhance the speech perception of students who are hard of hearing. This study compared the speech recognition abilities of children who are hard of hearing when they were using hearing aids with each of three frequency modulated (FM) or infrared devices. Eight 9 to 12-year-olds with mild to severe hearing loss used hearing aids alone or hearing aids in combination with three types of S/N-enhancing devices that are currently used in mainstream classrooms: (a) FM systems linked to personal hearing aids, (b) infrared sound field systems with speakers placed throughout the classroom, and (c) desktop personal sound field FM systems during the Hearing in Noise Test (HINT). The infrared ceiling sound field system did not provide benefit beyond that provided by hearing aids alone. Desktop and personal FM systems in combination with personal hearing aids provided substantial improvements in speech recognition.

Hearing loss gives rise to a number of disabilities. Problems in recognizing speech, especially in difficult environments, cause the largest number of complaints. Other kinds of problems concern the reduced ability to detect, identify and localize sounds quickly and reliably. Hearing loss affects both hearing-impaired people and other people in their environment--family members, fellow workers, etc. Several studies have shown that uncorrected hearing loss gives rise to poorer quality of life, increased isolation, reduced social activity, and a feeling of being excluded, leading to an increase in symptoms of depression. These findings indicate the importance of early identification of hearing loss and rehabilitative support such as the fitting of hearing aids. Several studies also point to a significant connection between hearing loss and loss of cognitive functions.

The effectiveness of a 2-channel hearing aid with low-frequency compression and high-frequency linear amplification on a group of school-age hearing aid wearers was studied. Twenty-five children (age 6 to 15 yr) were fitted with 2-channel hearing aids for 12 weeks and with their own refitted (single-channel) hearing aids for 12 weeks. Speech perception in quiet and in noise was measured at the end of each 12 week period and questionnaires were given to teachers, parents, and children. Two-channel hearing aids showed significantly higher scores for speech perception in noise and significantly higher scores on satisfaction and benefit. Final choice of hearing aids at the end of the study by parents and children also favored the 2-channel device.

The function of bone anchored hearing aids (BAHA) was compared with conventional air conduction hearing aids (ACHA) through hearing tests and quality-of-life questionnaires. Patients using BAHAs because of profuse drainage from chronic suppurative otitis media and a comparison group of healthy volunteers participated in the study. When the BAHA was compared with the ACHA, there were no significant differences in any of the measures. The BAHA and the ACHA provided similar hearing functioning in hearing tests. The BAHA should be considered for patients with profuse ear drainage.

The goals of this study were to evaluate hearing, complications, and patient satisfaction with the bone-anchored hearing aid (BAHA) and to monitor long-term successful use through careful patient selection. In 11 participants aged 5 to 17 years, the PTA free-field air conduction improved 37%, and free-field speech discrimination improved 23%. Successful integration and implant use were achieved in 10 cases. All patients preferred the BAHA over the conventional bone-conduction hearing aid. The BAHA is a valuable device that can improve hearing and provide significant parent and patient satisfaction.

The performance of 48 listeners with normal hearing was compared to the performance of 46 listeners with documented hearing loss. Various conditions of sound coming from one direction or multiple directions were studied. The results indicated that when the noise around a listener was stationary, a first- or second-order directional microphone allowed a group of hearing-impaired listeners with mild-to-moderate, bilateral, sensorineural hearing loss to perform similarly to normal hearing listeners on a speech-in-noise task. When the noise source was moving around the listener, only the second-order (three-microphone) system set to an adaptive directional response allowed a group of hearing-impaired individuals with mild-to-moderate sensorineural hearing loss to perform similarly to young, normal-hearing individuals.

This paper reviews the advantages and disadvantages of hearing aids in both ears as opposed to one ear for older persons with bilateral symmetric hearing loss. Advantages of using two hearing aids, such as improved localization and speech recognition in noise, are presented as well as contraindications, increased costs, cosmetic concerns, decreased manipulation skills, and additional hearing aid management issues. It is concluded that bilateral amplification should be attempted for all elderly patients with symmetric hearing loss, unless a contraindication is suspected.

The acceptance of hearing aids for the management of children with otitis media with effusion (OME) was assessed. Thirty-nine children who had been given binaural hearing aids to manage OME were evaluated at routine follow-up after 6 months. Thirty-eight parents thought the aids were easy to use and 25 (66%) were completely satisfied with the management. Aided hearing improved by a mean of 17 dB over three frequencies, 0.5, 1.0, 2.0 Khz, and all parents reported subjective hearing improvement in their children. The stigma of a hearing aid was reported as minimal under the age of seven. Hearing aids provide a non-invasive way of managing the problems associated with OME.

The potential benefit of hearing instruments with multi-microphone technology was investigated in users with severe-to-profound hearing loss. Twenty-one experienced hearing aid users were fitted with high-power multi-microphone hearing instruments. A group of tests were performed. Only 10 subjects achieved 50% correct on the sentence test in noise with both their own instrument and the test instrument in the omnidirectional mode. However, 15 subjects succeeded in the sentence test in noise measurement in the directional mode. The average improvement of the directional over the omnidirectional mode was 13.7 dB. Loudness was judged 'medium loud' for both listening programs. Sound quality and intelligibility were rated significantly better for the zoom program. Compared to their own instrument, users' satisfaction with the test instrument was significantly higher, especially in noisy listening situations.

The listening needs of the elderly have not been successfully addressed with hearing aids alone. Assistive listening devices and systems (ALDs), either alone or with the use of personal hearing aids, can aid listening in various sound environments, especially those in which excessive noise, reverberation and distance exist between the listener and sound source. Listening situations that are especially difficult even with hearing aids, such as listening in large groups, on the telephone, in restaurants and at concerts and movies, are ideally suited for ALD use. ALDs can reduce the impact of hearing loss and also ensure safety for older individuals. This review article explored the issues involved in ALD use with a particular emphasis on who are candidates for ALD use, issues related to ALD use by older individuals, fitting considerations, reasons why ALDs are rejected by older adults, and ways to avoid these potential problems.

The effects of sound field FM amplification (SFA) on speech perception performance were investigated in this 2-year study. Kindergarten children with normal hearing were randomly assigned to a treatment group, which comprised 7 classrooms that had SFA systems installed in them, and to a control group, which comprised another 7 classrooms that did not have any amplification available. Improvements in speech perception performance were demonstrated in the treatment group much sooner than the control group. However, this difference was not found by the end of the study. The only significant difference measured was that the treatment group performed significantly better than the control group when the stimuli were presented with SFA for the treatment group and without SFA for the control group. The teachers who used SFA enjoyed using amplification in their classrooms and felt that their students enjoyed using it as well.

Children with significant high-frequency hearing loss may be difficult to fit with hearing aids using conventional amplification. Frequency-lowering hearing aids using dynamic speech recoding (DSR) technology have been proposed as a possible way to reach full speech audibility. The current study investigated 78 children from ages 1.3 to 21.6 years who wore DSR hearing aids. These hearing aids provided significant improvements in pure-tone average (PTA) and high-frequency PTA. A subgroup of 19 children were previous users of conventional hearing aids. These children showed a mean improvement of 11 dB in PTA and 12.5% in word recognition scores for DSR versus conventional amplification. However, DSR hearing aids required repair 3 times as often as conventional hearing aids. The greatest benefit was seen in children whose word recognition scores were poorest using conventional hearing aids.

The impact of an intervention program on hearing aid functioning and maintenance was evaluated. The program targeted 29 teenagers who wore hearing aids, and 7 of their teachers. Results were monitored on the hearing aids' functioning over a 12-week period beginning before intervention and concluding 3 weeks after intervention ended. The 6-week intervention consisted of instruction in hearing aid maintenance. The number of functioning hearing aids increased significantly following intervention, and continued to increase even after intervention ended. Both students and teachers acquired new knowledge. The study highlights the need for intervention programs in hearing aid maintenance and their benefits to adolescent students and their teachers.

Twenty-one teenagers who were deafened by neurofibromatosis 2 and who underwent implantation with a multichannel auditory brainstem implantation (ABI) were categorized according to side of implantation, presence of remaining hearing, incidence of non-auditory sensations, and ABI use or nonuse. Nineteen (95%) of 20 teenagers tested received hearing sensations from their ABIs. Eleven teenagers used their ABIs regularly, but 8 did not. The multichannel ABI was found to be an effective means of providing hearing sensations to young patients deafened by neurofibromatosis 2. Factors such as expectations, personal motivation, and family support are important factors in successful adaptation to the device.

The bone-anchored hearing aid (BAHA) system uses a titanium implant to send sound directly to the inner ear through the bones of the skull. Children as young as 18 months have used this device. This study evaluated the methods of patient selection, the safety and effectiveness of the implantation procedure, and the level of patient satisfaction after BAHA implantation in children. Twenty patients who received 25 implants with post-implantation follow-up of 6 months or greater, were included. All patients and caregivers reported greater than 95% improvement in patient-identified listening situations. Pure-tone averages improved from a mean of 49 dB for the better hearing ear before surgery to 16 dB with the BAHA set at normal listening levels. The BAHA provided a safe and effective means of rehabilitation of conductive or mixed hearing loss in this group of children. Patients reported a high level of satisfaction and continued use of their devices.

Recent research on the importance of high-frequency amplification for speech perception in adults and children with hearing loss were reviewed and early data was provided on the phonological development of normal-hearing and hearing-impaired infants. Three groups of children were recruited: 20 normal-hearing children, 12 hearing-impaired children who received hearing aids up to 12 months of age (early-ID group), and 4 hearing-impaired children identified with hearing loss after 12 months of age (late-ID group). Compared with the normal-hearing group, the 3 children from the early-ID group showed marked delays in the acquisition of all phonemes. Delays for the 2 children from the late-ID group were substantially longer. Results suggest that the bandwidth of current behind-the-ear hearing aids is inadequate to accurately represent the high-frequency sounds of speech. Early data on phonological development in infants with hearing loss suggest that the greatest delays occur for fricatives, consistent with predictions based on hearing-aid bandwidth.

Bone-anchored hearing aids (BAHAs) are indicated for use in children with bilateral microtia or chronic suppurative otitis media, in which conventional hearing aids cannot be used. Nineteen children using BAHAs were reviewed. Bone integration was achieved in 95% of patients. Use of pediatric BAHAs in this population was found to be a reliable and successful method for hearing rehabilitation.

Related Topics

Motor and Nonverbal Skills in Deaf Children

This study explored the role of hearing in development of motor, balance skills and non-verbal skills. Fifty-four children between 5 to 9 years old with severe or profound bilateral prelocutive deafness but with no neurological or cognitive impairment were studied. Of these, 25 had received an early cochlear implant. Patients were compared with 40 children with normal hearing. All were given non-verbal neurological and psychological tests and a balance test, and were timed for simple and complex movement of limbs. Deafness, whether treated by cochlear implants or not, resulted in a delay in the development of complex motor sequences and balance. Lack of auditory input was also associated with lower scores in some visual tasks and sustained attention. These differences were not observed in children with cochlear implants. Hearing contributes to the development of spatial integration, motor control, and attention. An early cochlear implant supports good verbal development and might also improve non-verbal skills.

Genetic Factors

Deafness is the most common form of sensory impairment in humans. Depending on the age of onset, hearing impairment can affect oral language acquisition, cognitive development and psychosocial development. This article covers the latest advances in gene therapy for alleviating or preventing hearing loss and highlights some of the most recent developments in the field.

Data for prelingual hearing loss show that 1 newborn in 1,000 is born with severe to profound hearing loss, and in half of that number the loss is inherited. Some genes responsible for sensorineural hearing impairment have been cloned during the last several years, and the underlying mechanisms causing hearing impairment have begun to be clarified due to recent developments in molecular genetics. Clinical and genetic findings are reviewed in this paper.

Hearing loss is a common disorder that often has a neurologic cause. There has been significant progress in the discovery of the genes that cause sensorineural hearing loss, and this has led to increased understanding of the causes of both syndromic and nonsyndromic hearing problems. This review describes the genes that cover the range of processes involved in neurologic development and function. Interactions between genes as well as between genes and environmental factors are also discussed. Understanding of these processes should lead to earlier and more accurate diagnosis and more effective treatment for neurologic disorders and hearing loss.