Journal of the Royal Society of Medicine Volume 85 November 1992 2 Brewerton DA, Caffrey M, Hart FD, James DCO, Nicholls A, Sturrock RD. Ankylosing spondylitis and HL-A 27. Lancet 1973i:904-7 3 Brewerton DA, Caffrey MFP, James DCO., The histocompatibility antigen (WL-A 27) and its relation to disease. J Rheumatol 1974;1;249-53 4 Sinha AA, Brautbar C, Szafer F, et al A. newly characterised HLA' DQ,B allele associated with pemphigus vulgaris. Science 1988;239:1026-9 5 Sheehy MJ, Scharf SJ, Rowe JR,t aL A- diabetes-susceptible HLA haplotype is best defned by a combination of HLA-DR and -DQ alleles. J Clin Invest 1989,83:830-5 6 Julier C, Hyer RN, Davies J, et at Insulin-IGF2 region on chromosome lip encodes a gene implicated in HLADR4-dependent diabetes susceptibility. Nature 1991; 354:155-9 7 Svejgaard A, Platz P, Ryder LP. HLA and disease 1982 - a survey. Immunol Rev 1983;70:193-218 8 Germain RN. Antigen presentation. The second class story. Nature 1991;353:605-7 9 Kisielow P, Teh HS, Bluthmann H, Von Boehmer H. Positive selection of antigen-specific T cells in thymus by restricting MHC molecules. Nature 1988;335:730-3 10 Kappler JW, Staerz U, White J, Marrack PC. S6lf. tolerance eliminates T cells specific for Mls-modified products of the major histocompatibility complex. Nature 1988;332:35-40 11 Rees AJ, Peters DK, CoXopton DAS, Batchelor JR. Strong association between HLA DRw2 and antibody mediated Goodpasture's syndrome. Lancet 1978i:966-8 12. McDevitt HO, Perry R, Steinman LA. Monoclonal antiIa antibody therapy in animal models-of autoimmune disease. In: Evered D, Whelan J, eds. Autoimmunity and autoimmune disease (Ciba Foundadtion Symposium 129). Chichester, UK: John Wiley & Sons, 1987:184 13 Sakai K, Mitchell DJ, Hodgkinson SJ, Zamvil SS, Rothbard JB, Steinman L. Prevention of experimental allergic encephalomyelitis with peptides blocking T cell-MHC interaction. Proc Natl Acad Sci USA 1989; 86:9470-4 14 Vandenbark AA, Hashim G, Offner H. Immunization with a synthetic T-cell receptor V-region peptide prots against experimental auitoimmune encephalomyelitis. Nature 1989;341:541-4 15 Acha-Orbea H, Mitchell DJ, Timmerman L, et aL Limited heterogeneity of T cell receptors from lymphocytes mediating autoimmune encephalomyelitis allows specific immune intervention. CeU 1988;54:263-73 16 Baisch JM, Weeks T, Giles R, Hoover M, Stastny P, Capra DJ. Analysis of HLA-DQ genotypes andsuscept. ibility in insulin-dependent diabetes mellitus. N Engl J Med 1990;322:1836-41 17 Bill J, Appel VB, Palmer E. An analysis ofT-cell receptor variable region gene expression in major histocompatibility complex disparate mice. Proc Natl AcadSci USA

1988;85:9184-8 18 Oliveira DBG, Mitchison NA. Immune suppression genes. Clin Exp Immunol 1989;75:16777 19 Hirayama K, Matsushita S, Kikuchi I, luchi M, Ohta N, Sasazuki T. HLA-DQ is epistatic to HLA-IDR in controlling the immune response to schistosomal antigen in humans. Nati4re 1987;327:426-30

Cochlear implants in children When Alexander Volta daringly applied electricitWto his ears in 1780 he was paving the way for one of the

20 Fielder AHL, Walport MJ, Batchelor JR, et aL Family study, of the major histocompatibility complex in patients with systemic lupus erythematosus; importance of null alleles of C4A and C4B in determining disease susceptib lty. BMJ 1983;XW:425-8 21 Howard PF, Hochberg MC, Bias WB,. Arnett FC, McLean RH. Relationship between C4 null genes,.HLA-D region antigqns, and genetic susceptibility to systemic lupus erythematosu's in Caucasian and Black America:ns. Am J Med 1986;81:187-93 22 Woodrow JC. Immunogenetics of systemic lupus erythematosus. J Rheumatol-1988;15:197-9 23 Gre*n JR, Montasser M, Woodrow JC. The association of HLA-linked genes with systemic lupus erythematosus. Ann Hum Genet 1986;50:93-6 24 Hawkins BR, Wong KL,, Wong RWS, Chan KH, Dunckley H, Serjeantson SW. Strong. association between the major histocompatibility complex and systemic lupus erythematosus in Southern Chinese. J Rheumatol 1987;14:1128-31 25 Goldstein R, Olsen MPL, Arnett FC, Duvic M, Pollack MS, Reveille JD. Deletion of C4A genes in Black Americans with systemic lupus erythematosus. Arthritis Rheum 1988;31:S22. (Abstract) 26 Glass D, Raum D, Gibson D, Stillman JS, Schur PH. Inherited deficiency of the second component of comple-ment. Rheumatic disease associations, J, Cljn Invest 1976;58:853-61 27 Agnello- V. Complement deficiency states. Msdicine

1978;57:1-23 28 Rynes RI. Inherited complement deficiency states and SLE; Clin Rheum Dis 1982;8:29-47 29 Lachmann PJ. Complement - friend- or foe?. Br J Rheumatot 1987;26:409-15 30 Jac CO, Fronek Z, Lewis GD, Koo M, Hansen JA, McDevitt HO. Heritable major histompatibility conplex class UI-associated differences in production of-tumour necrosis factor alpha: relevance to genetic predisposition to systemic lupus erythematosus. Proc Natl Acad Sci

USA 1990;87:1233-7 31 Fronek Z, Timmerman LA, Alper CA, et aL Major histocompatibility complex genes and susceptibility to systemic lupus erythematosus. Arthritis Rheum 1990;

33:1542-53 32 Jacob CO, McDevitt HO. Tumour necrosis factor-alpha in murine autoimmune 'lupus' nephritis. Nature 1988; 331:356-8 33 Faustinan D, Li X, Lin-HY, etaL Linkage of faty major histocompatibility class I to autoimmune diabetes.

Science.1991;254:1756-61 34 Hoover ML, Angelini G, Ball E, et al Insulin dependent diabpels mellitus is associated with polymorphic forms of-the T cell receptor beta chain gene. Clin Res 1986; e 196 S4.72.A 35 Demaine AG, Vaughan RW, Taube DH, Welsh KI. Association of membianous -nephropathy- with T-cell receptor constant beta chain and mimunoglobuin heavy chain switch region polymorphisms. Immunogenetics

1988;2719-23 .36 Schur PH, Pandey JP, Fedrick JA. Gm alotypes in white patieAts with systemic lupus erythematosus. Arthritis Rheum 1985;28:828-30

most important advances in the treatment of profound hearing loss nearly two centuiies later. His description' of the experiment is remarkably candid: 'I began to hear a sound, or rathernoise, in the ears which I cannot well define. This noise continued incessantly all the time the circle was complete.

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The disagreeable sensation, which I apprehended might be dangerous of the shock in the brain, prevented me from repeating this experiment'. The earliest deliberate therapeutic attempts to harness electrical energy to alleviate hearing impairment began in earnest in the late 1960s24. These attempts were greeted with anger and derision both from sections of the deaf community and the medical profession. Happily, the determination of the early investigators ensured the continued development of this new technology and its eventual acceptance as a treatment option for the profoundly deaf. Profound deafness in childhood has far-reaching effects on the child, the family and on society. The critical years for speech and language development are the very early years of life, before the age of five. Sound deprivation during this period may result in failure to integrate hearing into the developing nervous system, and the capacity to learn spoken language and produce speech may be permanently impaired. This contrasts sharply with the onset of deafness in adult life, when the language that has been acquired and many aspects of speech production can be retained. The effect of hearing impairment on educational achievement is immense5. It is a sad fact that many deaf children leave school at the age of sixteen, after years of intense training, with a reading age of an 8-year-old and speech which is generally unintelligible. Their vocational choices are severely restricted, resulting in low self-esteem, poor socioeconomic status and a high dependence on social and psychiatric services. Over 90% of all deaf children have hearing parents and the emotional trauma within the family of adapting to profound deafness may be considerable. Severe sensorineural hearing loss in childhood may be congenital or acquired, the former accounting for about 80% of cases6. The commonest cause of acquired sensorineural hearing loss is bacterial meningitis which primarily affects children in the first 2 years of life. The incidence of profound deafness following bacterial meningitis is about 1.5% which is equivalent to an incidence of 46 cases per year in the UK6. There is evidence to suggest that the more timely administration of steroids may reduce the level of hearing loss7. Delay in diagnosis is often blamed for the deafness but there is little evidence to support this. A major concern following meningitis is that occasionally new bone may gradually form in the cochlea. Unless implantation is undertaken early following meningitis, this new bone may prevent the insertion of electrodes rendering a child unsuitable for implantation or limiting the options to the less beneficial extracochlear implant. A cochlear implant is a means of by-passing the function of the sensory hair cells and stimulating the auditory neurones directly. The hair cells in the normal cochlea convert sound to electrical impulses which are passed on to the auditory nerve. In many instances of profound deafness, the hair cells are lost but the nerve fibres remain. In the implanted patient, a body-worn speech processor converts the most important elements of speech into electrical signals. These signals are then transmitted to electrodes implanted in the cochlea with resultant excitation of the surviving auditory neurones. An implant system may have a single electrode (single channel) or several electrodes (multichannel). In profoundly deafened adults, cochlear implants have been shown to reduce

the sense of auditory isolation, to improve lip-reading, and in some cases to allow speech to be understood without lip reading, such that the recipient is able to use a telephone8. Warning sounds such as fire alarms and car horns can be appreciated by most. Not surprisingly, investigators have been keen to determine if these same benefits could accrue to totally or near-totally deafened children. At present, implants are indicated for children who derive little or no benefit from the most powerful conventional hearing aids. This assumes that the hearing aids and ear moulds are correctly fitted and fimctioning, that they have been worn for sufficiently long and that appropriate support has been provided for the child and the family. Difficulty may arise in determining just how much benefit from a hearing aid is too little to warrant consideration of cochlear implantation. In practice, the aided hearing thresholds will usually be in excess of 80 dB across the frequency range. Electrophysiological testing and radiological evaluation of the cochlea are necessary. A major difficulty is the reliable assessment of speech recognition in young deaf children who are cognitively and linguistically immature. Whether for purposes of case selection, electrode tuning or outcome monitoring, such assessments cannot be made with sufficient reliability in a child under 2 years of age, and in most audiology services, techniques for testing pre- or perilinguistic children younger than this are lacking. Also crucial to the selection process is the attitude of parents and teachers, because the success of rehabilitation hinges on their continued support for the child in the years following implantation. It is essential that implant teams paint a realistic picture of the likely outcome and not focus on the results of one or two 'star' patients. Parents should be made fully aware that cochlear implants are but one of many ways of reducing the sensory deficit imposed by deafness. The evaluations requisite prior to implantation are thus complex, and the expertise to make them is likely to be confined to those centres with considerable practical experience in the management of very young profoundly deaf children. The implantation of children outside such centres would seem inappropriate at this time. The risks of the implant surgery are siunilar to those of mastoid surgery and, in experienced hands, are extremely low9. The cochlea is of adult size at birth but the mastoid bone may be small and soft, making it difficult to anchor the implanted electronics satisfactorily. An expansile electrode system has yet to be devised that will accommodate head growth. A major concern has been the possibility that the electrodes, travelling as they do from middle to inner ear, could act as a conduit for the spread of infection to the labyrinth (and from there to the meninges) during otitis media9; in practice these fears have not been substantiated but concerns still remain. The effects of electrical stimulation on the auditory system over a lifetime are unknown but no deleterious results are noted to date10; on the contrary, electrical stimulation in animals has been shown to have a beneficial effect on nerve survival within the cochlea'1. It is reassuring that if a device fails or is removed to upgrade to a newer technology, reimplantation is

usually possible'2. The immediate goal of implantation is to introduce the child to recognizable sound patterns without causing any pain. Following implantation, the system

Journal of the Royal Society of-Medicine Volume 85 November 1992

has to be programmed for each patient. The range of electrical current from the barely perceptible -to the painful is generally very narrow and young children's responses are extremely difficult to measure or judge. The attitude of a child to the new sound -sensation can vary from overt pleasure to absolute fear, and parental emotions can run very high. With contemporary systems becoming increasingly complex, programming for young children may tax the skills of audiological scientists, speech therapists and teachers of the deaf for some months. Once the electrode 'map' has been programmed, the emphasis is on encouraging the child to use the new sensory input to monitor the noisy world about him, in the classroom and in the home. Attempts to-improve speech perception and production need to be tailored for each child. Often a compromise is required between the age-appropriateness of the material and the linguistic competence of the child. Parents are often frustrated and sometimes disillusioned at the slow pace of progress, as there may be a silent lag, phase during the early stages of language acquisition prior to any changes in the child's speech performance. It is essential to main parents' niorale during the many emotional troughs astheir continued involvement in rehabilitation is crucial. In considering the results of cochlear implants in children, four main indicators need tobe adds3: (1) basic hearing results, (2) language development and speech production, (3) educational achievement and (4) psychosocial adjustment. None of these variables should be considered without due regard for the many influences on a child's development, eg social circumstances, family support, educational setting. Several studies clearly demonstrate the significant benefit across a broad spectrum of abilities derived from a cochlear implantl4"5. With multichannel devices, many-young children can achieve speech understanding without lipreading, and have demonstrable improvement in speech production: and language acquisition. -The factors that- most consistently affect outcome are-(1) age at onset of deafness - the older the child, the more likely he is to retain language and so rehabilitation is simpler, (2) duration of deafness - the longer -the interval between deafness and implantation, the poorer the outcome and (3) the educational setting - educational management is a vital factor in the progress of all hearing impaired children,- including thas -with cochlear implants. While young congenitally deaf children do less well in the short term, the gap, between them and those with acquired losses narrows with the passage of time'6. Congenitally deaf teen, agers have proved a disappointing group: the patient satisfaction rate is low and the non-user rate tendsto be high. Whether this is due to motivational reasons, problems of identity or to the duration of deafness is not entirely clear. The first wholly paediatric cochlear implant pro. gramme was startedl in Nottingham in 1989 withcharitable funding. The cost of- implanting and rehabilitating a child is approximately £30,000¢-In 1991 the Departmeult of Health launched a central initiative in cochlearl implantatoi coupled to a multi. centre, multi-facetted evaluat-ion study. Ovrer 20 children in the UK arercipients fcocklear implants and well over 1000 children have been implanted world wide. While it.is customry to bemoan the tardiness of the NHS at embracing new dlevelopments

it is worth noting that, in this particular area, service provision in the UK now exceeds that available in many other European countries, with the notable exception of Germany. The competition for resources in all Western economies, grappling with the steep rise in health care expenditure, means that the survival of any new technology can only be assured if cost is shown to match benefit. This has not yet been demonstrated formally for cochlear implants and there is a compelling need to do so. It is imperative that data be gathered across paediatric implant groups, which could justify the very substantial resources to maintain these programmes on the scale apparently needed. The natural tendency to develop more complex and more expensive devices that are ikely to meet the needs of fewer deafened patients must be resisted. It would be a tragedy if service provision were to be crippled- by soaring expenses compounded by a failure scientifically to evaluate the clinical effectiveness of this major technological advance.

Acknowledgment The author acknowledges the constructive criticism received from the staff of the Nottingham Paediatric Cocl~lear Implant Group and of the MRC Institute of Hearing Research, Nottingham.

Gerard M O'Donoghue Consultant Otolaryngologist Queen's Medical Centre, University Hospital, Nottingham NG7 2 UH References 1. Volta A. On the electricity excited by the mere contact of conducting substances of different kinds. Trans R-Soc Phil 1800;90:403-31 2 Djourno A, Eyries C. Proth6se auditive par excitation electriqute a distance du nerf sensoriel a, l'aide d'un bobinage inclus a demeure. Presse Med 1957;35: 14-17 3 Mchelson RP. Electrical stimulation of the human

cochlea, Arch Otolaryngol 1971;93:317-23

4 House 'WF, Berliner K,- Crary W, et aL Cochlear implants. Ann Otol Ahinol Laryngol 1976;85(suppl): 3-6 5 Wood D, Wood H, Griffiths A, 'Howarth I. In: -Teaching and talking- with deiaf children. Chichestet: JWilIey and Sons, 1986:94-111 6 Dav A;, Wood S. The epidemiology of childhood hearing impairment: Factors relevant to plaining of services. Br J Audiol 1992;26:77-90. 7 Lebel MH, Bishara BJ, Syrogiannopolus GA, et aL. .DexameUtiasone therapy for bacterial meningitis. NEng

J Med 1988;319:964-71 8 Brown AM, Dowell RC, Martin LF, et aL In: Clark GM,

'Tong YC, Patrick JF, eds, Cochkar prostheses. Training of communication skills in implanted-deaf adults. Edinburgh: Churchill Livingst6ne, 1990k181-92' 9 Clark GM, Cohen NL, Shepherd RK.- Surgical and safety considerations of multichannel cochlear implants in children. Ear Hear 1991;12:15-2410 LeaIeJones PA, Rebacher SJ. Cochlear pathology with chronlically implanted Iscl tympani electrodes. Coolea:r Prostheses. Ann N Y Acadl Ssi 1983;406:203-23 11 Leake PA, Hulterantz M, Snyder RL, et aL Effects of chrnic electical stmulation in neonatafly deafened cats. -Thirteenth- Midwinter Research Meeting Association. Res tolarzyngol 1990:328(Abstr) 12 Jackler:RK, Leake PA, McKerrowWS. Cochlear implant revrision: effects of reimplantation on the cochlea. Ann Otol*> Rhinol Layngol 1989,9&813-20 -

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13 Tyler RS, Davis JM, Lansing CR. Cochlear implants in young children. American Speech-Language-Hearing Association 1987;29:41-9 14 Staller SJ, Dowell RC, Beiter AL, et aL Perceptual abilities of children with the nucleus 22-channel cochlear implant. Ear Hear 1991:12(suppl):34-47

What's in a title - Mr or Dr? The British like doing things their own way. They always have done, and probably always will. However as we approach 1992 and closer links with out European neighbours develop, will there be less scope for individuality? 1992 represents the start of a universal general 'jobs and goods' market amongst Member States ofthe European Community. This has already been the situation for the medical professions for some time. Since the 'Free Circulation Directive' of December 1976, migration of members of the profession has been possible, there being mutual recognition of different Member States' relevant diplomas. However, as has been pointed out', there has been no standardization oi medical training, duration of training within a specific specialty, nor even what represents a- medical specialty. The trend towards uniformity of training within the Community poses interesting questions as to what should be the accepted 'titles' of different members of the medical and allied professions. The word doctor has its origins in Latin where it means teacher, and even in more modern languages it retains the same meaning. Chambers Twentieth Century Dictionary defines doctor as: 'teacher (arch.) originally implying competency to teach'2, and Butterworth's medical dictionary pits the teachitig definition before the medical definition3.,It is nowadays generally accepted that a 'doctor' is one who provides medical care and advice (along with the other duties pertaining to their practice). These people are given the title 'Dr'; yet in our midst there is a group of doctors who do not use this title - the surgeons; who prefer to be known as 'Mister' or 'r. In almost every other country that we can think of, with the possible exception of Australia, where many surgeons have an FRCS, as well as FACS, this is not the case and all medics are known as 'doctor'. The title 'Doctor' is in fact a courtesy title to members of the medical profession, and only those, who have achieved certain academic qualifications are allowed to use such a title by right, namely an MD, PhD, DSc, DDS. Many of the. holders of these degrees remain within the academic community undertaking not only further research but also actively teaching their subjects, and could therefore be said to be even more worthy of the title 'Doctor'. However, in the minds of many people a doctor is gtill, a doctor! This can lead to a small amount of confusion in,the general public. Those who are or who have -been involved in hospital life do not. appear to have a problem when addressing medical staff. There are few

15 Osberger MJ, Robbins AM, Miyamoto RT.. Speech perception abilities of children with cochlear implants, tpcile aids, or heanug aide. Am 4 Otol 1991;12(suppl): 105-15 16 Qiittner AL, Steck JT. Predictors of cocJ4lear implant use in children. Am J Otol 1991;12(suppl):89-94

surgeons who have not been incorrectly addressed by their patients at one time or another as 'doctor', and in these circumstances has to decide whether to correct that person. Yet in another situation, when the call goes out 'Is there a-doctor in-the house?' there is seldom a rush of PhDs' to uassist the needyl Where does this anomaly come from?-The history ofthe title 'Mister' for surgeons, is a little uncertain. In his paper Eibel4 reviewed some of -the likely origins. He suggests that after the decline of Rome, surgery was largely the domain of monks assisted by barbers. In the 12th century, however, the Pope decreed that monks must no longer shed blood, the result of which was to give great heart to the barbers who began more advanced surgery such -s bloodletting, fracture treatment, and tooth-pulling. Hence this group became known as the barber-surgeons (although the monksdid continue to act in an advisory or consultant capacity). At the same time, there was another group of 'surgeons' who were apprenticed, and since unqualified, not titled 'doctor'. These groups .joined in 1493 to better define their respective job desrpin King Henry VYII formalized this arrangement in 1-540, and the -affiliation became, known as 'Masters, Governors, ofthe Mystery and Commonalty of Barbers and Surgery of London'. Any miber of this- group was now allowed to -be aded as 'Master', which in time became 'Mister'. The union with the barbers lasted until 1745 when the surgeons lobbied Parliament to effect-a separation, and thus ended this partnership4 Nowadays, with increasing international meetings and cooperation, uniformity of -title may seem to be a otep forward amongst -colleagues, who seek to advance their common knowledge for the common good. Yetthere is also t-he opinion -that there is little con^sion currently and that there is no need for change, anid that the traditional British way should be; maintained, since the attainment- of higher surgical qualifications bringswith it the 'higher' title

of 'Misier'. There is also currently much debate in the -dental

press that dentists should be allowed to use the courtesy title 'Doctor'. Currently this is illegal (unlees the individual holds a doctorate or medical degree). European dentists are addressed as 'Doctor?, until they; decide to practice in the UK. Herethey must be addressed as 'Mister' even;if tbeir degree is, for itance, a French doctor of dental ;surger-y. The current moves to the use of such a title in dealings with patients is being supported- by, the Biritish Dlental Association, the- General -Dental Practitioners Association and the Women in Dentistry group.

These organizations h&ve, following little consultation with their grass-roots members, decided to

Cochlear implants in children.

Journal of the Royal Society of Medicine Volume 85 November 1992 2 Brewerton DA, Caffrey M, Hart FD, James DCO, Nicholls A, Sturrock RD. Ankylosing sp...
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