With the goal of universal detection of hearing loss in infants by

3 months of age, and appropriate intervention (e.g., amplifica tion) by 6 months of age,50,51 it is likely that ever-increasing numbers of very young children will be identified as potential implant candidates. We know that early identification (i.e., by

6 months of age) and early intervention with hearing aids

(HAs) have a significant effect on language development in chil dren with hearing loss,52 but the spoken word recognition and receptive language benefits of early implantation in children with profound deafness have not been quantified, and critical age limits for cochlear implantation have not been identified.

Cochlear implantation earlier than the current FDA

accepted age of 12 months is feasible as the target organ, the cochlea, is adult size at birth. The small dimensions of the temporal bone must be accounted for, but the facial recess and mastoid antrum that provide access to the middle ear for electrode placement are adequately developed before the age of 1 year. In fact, several centers have chosen to implant children under

12 months of age. Furthermore, implanting children under the age of 12 months may have substantial advantages when the etiology of deafness is meningitis. Progressive intracochlear fibrosis and ossification may occur, which can preclude stan dard electrode insertion. A relatively short window exists during which this advancing process can be circumvented.

Nonetheless, implantation of the very young child remains controversial because the audiological assessment and management of this population is extremely challenging. Profound deafness must be substantiated and the inability to benefit from conventional hearing aids demonstrated. However, a compelling argument supporting implantation at the earliest possible time can be made because the development of speech perception, speech production, and language competence normally begins early in infancy. In addition, electrical stimulation has been shown to prevent at least some of the degenerative changes in the central auditory pathways caused by auditory deprivation.53

The extension of cochlear implantation to children with ever higher levels of preimplant residual hearing should be approached cautiously. Surgical implantation of the electrode array results in the loss of residual hearing in that ear. Thus, cochlear implantation should not be considered unless it seems likely that a given child will receive more benefit from this device than from conventional amplification. Recently, mounting evidence has been found to suggest that some children with severe hearing loss may derive as much or even more benefit from a cochlear implant than as from a well-fitted HA. In amplifying sound for an individual with hearing loss, an assumption is made that the acoustic-phonetic patterns of speech must be detected before they can be discriminated and recognized. To accomplish this goal, audibility across a broad frequency range is typically prescribed as a means of maximizing speech intelli-gibility.54 This, in fact, has been the goal of most standard HA prescriptions. For severe to profound losses, however, supplying adequate gain across a broad frequency range can present a special challenge to the clinician. Moreover, achieving this amount of amplification may cause acoustic feedback, necessitating a reduction in gain and audibility.55 Another issue concerns the risk of delivering high levels of sound to the impaired ear. According to Macrae,56,57 the sound pressure level required to achieve audibility for individuals with severe to profound hearing loss has the potential to destroy remaining hair cells due to excessive noise exposure. Thus, a trade-off may exist between providing audible speech and risking increased damage to inner ear structures. Lastly, there is some question as to the extent of benefit that may actually be realized by amplifying high frequencies to audible levels for this magnitude of loss. Recent research has suggested that provision of adequate audibility for losses of > 60 dB HL at > 3000 Hz does not improve speech recognition and may even degrade performance.58-60 Preliminary research has suggested that some children with cochlear implants obtain spoken word recognition abilities that surpass those of other children with severe hearing loss (i.e., pure tone averages (PTAs) of 70 to 90 dB HL) who use well-fit HAs.14'61'62 Given the limitations imposed in providing high levels of amplified speech to children with severe to profound hearing loss, the evidence suggests that a cochlear implant could provide added benefit for a select population of children with this magnitude of hearing loss.

The encouraging results obtained with younger children and those who have some useful hearing prior to implantation have led investigators to push the boundaries of cochlear implantation criteria further than ever before. With the continued evolution and expansion of cochlear implant candidacy it is crucial that we develop techniques to quantify hearing loss, to fit both hearing aids and cochlear implants, and to document the effects of implantation in these very young children.


Miyamoto et al.—CHAPTER 80

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2. Staller S, Beiter AL, Brimacombe JA, et al. Pediatric performance with the Nucleus 22-channel cochlear implant system. Am J Otol 1991;12:126-136

3. Staller SJ. Clinical trials of the Nucleus 24 in adults and children. Presented at the tenth annual convention of the American Academy of Audiology, Los Angeles, CA; 1998

4. Wilson BS. Signal processing. In: Tyler RS, editor. Cochlear Implants: Audiological Foundations. San Diego: Singular; 1993:35-85

5. Wilson BS, Lawson DT, Finley CC, Wolford RD. Coding strategies for multichannel cochlear prostheses. Am J Otol 1991;12(suppl 1):56-61

6. Wilson BS, Lawson DT, Finley CC, Wolford RD. Importance of patient and processor variables in determining outcomes with cochlear implants. J Speech Hear Res 1993;36:373-379

7. Cowan RSC, DelDot J, Barker EJ, et al. Speech perception results for children with implants with different levels of preoperative residual hearing. Am J Otol 1997;18:125-126

8. Cowan RSC, Galvin KL, Klieve S, et al. Contributing factors to improved speech perception in children using the Nucleus 22-channel cochlear prosthesis. In: Honjo I, Takahashi H, editors. Cochlear Implant and Related Sciences Update. Advances in Otorhinolaryngology, vol 52. Basel: Karger; 1997:193-197

9. Kirk KI, Pisoni DB, Osberger MJ. Lexical effects on spoken word recognition by pediatric cochlear implant users. Ear Hear 1995;16:470-481

10. Miyamoto RT, Kirk KI, Svirsky MA, Sehgal ST. Communication skills in pediatric cochlear implant recipients. Acta Otolaryngol (Stockh) 1999;119:219-224

11. Osberger MJ, Fisher L, Zimmerman-Phillips S, et al. Speech recognition performance of older children with cochlear implants. Am J Otol 1998;19:152-157

12. Sehgal ST, Kirk KI, Svirsky MA, Miyamoto RT. The effects of processor strategy on the speech perception performance of pediatric Nucleus multichannel cochlear implant users. Ear Hear 1998;19:149-161

13. Zimmerman-Phillips S, Osberger MJ, Robbins AM. Infant Toddler Meaningful Auditory Integration Scale (IT-MAIS). Sylmar, CA: Advanced Bionics; 1997

14. Eisenberg LS, Martinez AS, Sennaroglu G, Osberger MJ. Establishing new criteria in selecting children for a cochlear implant: performance of "platinum" hearing aid users. Ann Otol Rhinol Laryngol. In press

15. Woodward AL, Markman EM. Early word learning. In: Damon W, Kuhn D, Siegler R, editors. Handbook of Child Psychology. Vol 2: Cognition, Perception and Language. New York: John Wiley & Sons; 1997:371-420

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17. Fryauf-Bertschy H, Tyler RS, Kelsay DMR, et al. Cochlear implant use by prelingually deafened children: the influences of age at implant and length of device use. J Speech Hear Res 1997;40:183-199

18. Miyamoto RT, Osberger MJ, Robbins AM, et al. Comparison of sensory aids in deaf children. Ann Otol Rhinol Laryngol 1989;98:2-7

19. Tyler RS, Fryauf-Bertschy H, Gantz BJ, et al. Speech perception in prelingually implanted children after four years. In: Honjo I, Takahashi H, eds. Cochlear Implant and Related Science Update. Advances in Otolaryngology, vol 52. Basel: Karger; 1997:187-192

20. Tyler RS, Fryauf-Bertschy H, Kelsay DMR, et al. Speech perception by prelingually deaf children using cochlear implants. Otolaryngol Head Neck Surg 1997;117:180-187

21. Tyler RS, Parkinson AJ, Fryauf-Bertschy H, et al. Speech perception by prelingually deaf children and postlingually deaf adults with cochlear implant. Scand J Audiol 1997; 26(suppl 46):65-71

22. Bollard PM, Chute PM, Popp A, Parisier SC. Specific language growth in young children using the Clarion cochlear implant. Ann Otol Rhinol Laryngol 1999;108(suppl 117):119-123

23. Pisoni DB, Kirk KI, Svirsky MA, Miyamoto RT. Looking at the "stars": a first report on the intercorrelations among measures of speech perception, intelligibility and language in pediatric cochlear implant users. J Speech Lang Hear Res. In press

24. Robbins AM, Bollard PM, Green J. Language development in children implanted with the Clarion cochlear implant. Ann Otol Rhinol Laryngol 1999;108(suppl 117):113-118

25. Robbins AM, Svirsky MA, Kirk KI. Children with implants can speak, but can they communicate? Otolaryngol Head Neck Surg 1997;117:155-160

26. Svirsky MA, Sloan RB, Caldwell M, Miyamoto RT. Speech intelligibility of prelingually deaf children with multichannel cochlear implants. Presented at the seventh symposium on cochlear implants in children, Iowa City, IA; 1998

27. Tyler RS, Tomblin JB, Spencer LJ, et al. How speech perception through a cochlear implant affects language and education. Otolaryngol Head Neck Surg. In press

28. Clark G. The University of Melbourne Nucleus multi-electrode cochlear implant. Adv Otol Rhinol Laryngol 1987;38:189

29. Schindler RA, Kessler DK, Rebscher SJ, et al. The UCSF/Storz multichannel cochlear implant: patient results. Laryngoscope 1986;96:597

30. Wilson BS, Finley CC, Lawson DT, Wolford RD, Eddington DK, Rabinowitz WM. Better speech recognition with cochlear implants. Nature 1991;352:236-237

31. Gstöttner WK, Baumgartner WD, Franz P, Hamzavi J. Cochlear implant deep-insertion surgery. Laryngoscope 1997;107:544-546

32. Hochmair ES. Clinically relevant aspects of the high-rate cisspeech coding strategy for cochlear implants. Abstracts of the first Asia Pacific symposium on cochlear implant and related sciences. Abst 19. 1996;47

33. McElveen JT, Carrasco VN, Miyamoto RT, et al. Surgical approaches for cochlear implantation in patients with cochlear malformations. In press

34. Gantz BJ, McCabe BF, Tyler RS. Use of multichannel cochlear implants in obstructed and obliterated cochleas. Oto-laryngol Head Neck Surg 1988;98:72-81

35. Steenerson RL, Gary LB, Wynens MS. Scala vestibuli cochlear implantations for labyrinthine ossification. Am J Otol 1990;11:360-363

36. Osberger MJ, Robbins AM, Todd SL, et al. Cochlear implants and tactile aids for children with profound hearing impairment. In: Bess F, Gravel J, Tharpe AM, editors. Amplification for Children with Auditory Deficits. Nashville, TN: Bill Wilkerson Center Press, 1996:283-308

37. Cowan RSC, Brown C, Whitford LA, et al. Speech perception in children using the advanced SPEAK speech-processing strategy. Ann Otol Rhinol Laryngol 1995;104(suppl 166): 318-321

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39. Erber NP. Auditory Training. Washington, DC: Alexander Graham Bell Association for the Deaf; 1982

40. Gantz BJ, Tyler RS, Woodworth G, et al. Results of multichannel cochlear implant in congenital and acquired prelin-gual deafness in children: five-year follow-up. Am J Otol 1994;15(suppl 2):1-8

41. Miyamoto RT, Osberger MJ, Todd SL, et al. Variables affecting implant performance in children. Laryngoscope 1994;9: 1120-1124

42. Miyamoto RT, Kirk KI, Robbins AM, et al. Speech perception and speech production skills of children with multichannel cochlear implants. Acta Otolaryngol 1996;116:240-243

43. Osberger MJ, Todd SL, Berry SW, et al. Effect of age at onset of deafness on children's speech perception abilities with a cochlear implant. Ann Otol Rhinol Laryngol 1991;100:883-888

44. Miyamoto RT, Kirk KI, Robbins AM, et al. Speech perception and speech intelligibility in children with multichannel cochlear implants. In: Honjo I, Takahashi H, eds. Cochlear Implant and Related Sciences Update. Advances in Otorhinolaryngology, vol 52. Basel: Karger; 1997:198-203

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46. Waltzman S, Cohen NL, Shapiro W. Effects of cochlear implantation on the young deaf child. In: Uziel AS, Mondain M, eds. Cochlear Implants in Children. Advances in Otorhi-nolaryngology, vol 50. Basel: Karger; 1995:125-128

47. Waltzman S, Cohen NL, Gomolin R, et al. Perception and production results in children implanted between two and five years of age. In: Honjo I, Takahashi H, eds. Cochlear Implant and Related Sciences Update. Advances in Otorhinolaryngology, vol 52. Basel: Karger; 1997:177-180

48. Zwolan TA, Zimmerman-Phillips S, Asbaugh CJ, et al. Cochlear implantation of children with minimal open-set speech recognition skills. Ear Hear 1997;18:240-251

49. Gantz B, Rubinstein J, Tyler R, et al. Long-term results of cochlear implants in children with residual hearing. Ann Otol Rhinol Laryngol. In press

50. American Academy of Pediatrics. Joint Committee on Infant Hearing Screening. 1994 position statement. Pediatrics 1994;95:152-156

51. American Academy of Pediatrics. Task force on newborn and infant hearing. Newborn and infant hearing loss: detection and intervention. Pediatrics 1999;103:527-530

52. Yoshinaga-Itano C, Sedey AL, Coulter DK, Mehl AL. Language of early- and later-identified children with hearing loss. Pediatrics 1998;102:1161-1171

53. Matsushima JI, Shepard RK, Seldon HL, et al. Electrical stimulation of the auditory nerve in deaf kittens: effects on cochlear nucleus morphology. Hear Res 1991;56:133-142

54. Skinner MW, Miller JD. Amplification bandwidth and intelligibility of speech in quiet and noise for listeners with sensorineural hearing loss. Audiology 1983;22:253-279

55. Skinner MW, Holden LK, Binzer SM. Aural rehabilitation for individuals with severe and profound hearing impairment: hearing aids, cochlear implants, counseling, and training. In: Valente M, ed. Strategies of Selecting and Verifying Hearing Aid Fittings. New York: Thieme Medical; 1996

56. Macrae JH. Permanent threshold shift association with over-amplification by hearing aids. J Speech Hear Res 1991;34: 403-414

57. Macrae JH. Prediction of deterioration in hearing due to hearing aid use. J Speech Hear Res 1991;34:661-660

58. Ching TYC, Dillon H, Byrne D. Speech recognition of hearing-impaired listeners: predictions from audibility and the limited role of high-frequency amplification. J Acoust Soc Am 1998;103:1128-1140

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Cochlear Implants in Congenitally Deaf Children

Laura W. Kretschmer


The history of cochlear implants is a somewhat recent one. The first experimental single-channel implant was provided to a child in 1980, and the first multichannel implant in a child was completed in Australia in 1985, with multisite trials begun with children in the United States the next year. Since the initial experimental work, it is estimated that about 12,000 to 15,000 persons worldwide have received implants, with approximately one-third of those being children. Most children with implants in the United States, in Australia, and in western Europe are deaf as a result of meningitis (45 to 64%). Those children with implants who are identified as having congenital onset of deafness is still a small subset. The push for early identification of hearing loss, and for early fitting of hearing aids, suggests that our attention will invariably be drawn to that subset of children with profound bilateral hearing loss who do not receive substantial benefit from conventional hearing aids, most of whom will have a congenital onset of deafness. It is readily accepted that any child who acquires deafness after the onset of spoken language and who receives limited benefit from amplification is a potential candidate for a cochlear implant. The analogous situation of an older child, adolescent, or adult who is deafened and is considered for an implant also causes little controversy. The question of an implant for the infant, toddler, or young child who has never had auditory experience should raise many cautions for the physician and implant teams, however.

The cochlear implant is not the end of habilitation in children with congenital deafness. Rather, it is just the beginning, constituting only one factor in the effort to promote the child's linguistic, educational, psychosocial, and intellectual development. Deafness may be considered a variation in the human condition by some, or a disability by others, but the most critical aspect of the deaf child's habilitation is the establishment of communication, whether or not an implant is involved. The heavy lifting of language acquisition is accomplished in normal hearing children by the fourth or fifth year of life. In view of the importance of these early years for language acquisition in general, it is an important goal to ensure that the first 4 or 5 years of life are primary language learning years for every child with congenital deafness as well.

The list of controversies surrounding the process of implantation in children with congenital deafness is substantial. The set of controversies discussed in this chapter, although not exhaustive, represents the most publicized and the most vexing issues:

(1) advisability of lowering the minimum age for implantation;

(2) deciding when benefit from conventional amplification is not sufficient to sustain communication development in a young child; (3) determining whether family and educational resources are sufficient to warrant and support implantation as part of the child's habilitation, including the question of which modes of communication (spoken versus sign language) seem to be most important to implant success; (4) the issue of deaf culture and how it should enter into parents' and professionals thinking about implantation; (5) whether or how the perspectives of the child might be taken into account; (6) the advisability of implantation in children with multiple neurologic and cognitive disabilities, including auditory neuropathy; (7) whether published data reflect the full range of outcomes for children who are implanted, to include those children who do not derive benefit or who voluntarily discard the implant; and (8) the implications of animal research on neural plasticity and cortical reorganization in regard to the use of implants in young children with congenital deafness. The best speech-processing schemes remain controversial among manufacturers and auditory researchers. (See comprehensive reports such as the 1997 Acta Otolaryngology supplement or the 1997 American Journal of Otology supplement for detailed information on cochlear implants in children, as well as Parkins1 for further information about processing schemes.)

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