A case is reported in which a Nucleus 22 channel intracochlear device was implanted a deaf/blind Hungarian adult with discharging ears suffering from Behçet's disease. Preconditioning surgery was employed three months prior to the implantation procedure to ensure a sterile, dry protected environment for the electrodes. One month after implantation, the patient exhibited excellent auditory discrimination capability at the time of the first switch on. We suggest that some deaf/blind individuals may serve as very good candidates for intracochlear implantatio

Czigner, J.

De Mora Mieszkowski, J.

Jori, J.

Kiss, J. G.

Szilvassy, J.

Szilvassy, Z.

Toth, F.

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The Journal of Laryngology and OtologyFebruary 1998, Vol. 112, pp. 169-171Cochlear implantation of a Hungarian deaf and blindpatient with discharging ears suffering from Behcet'sdiseaseJ. SZILVASSY, J. CZIGNER, J. JORI, F. TOTH, Z . SziLVASSY*, J. DE MORA MlESZKOWSKlt, J. G. KlSSAbstractA case is reported in which a Nucleus 22 channel intracochlear device was implanted a deaf/blind Hungarianadult with discharging ears suffering from Behcet's disease. Preconditioning surgery was employed threemonths prior to the implantation procedure to ensure a sterile, dry protected environment for the electrodes.One month after implantation, the patient exhibited excellent auditory discrimination capability at the time ofthe first switch on. We suggest that some deaf/blind individuals may serve as very good candidates forintracochlear implantation.Key words: Cochlear implant; Behcet's syndromeIntroductionCochlear implantation in normally-sighted individuals isgenerally regarded as a medical strategy which serves tosupplement lipreading skills. Cochlear implantation of thedeaf and blind patient was therefore initially considered anintervention of doubtful benefit and there have only been alimited number of implantations round the world. Never-theless, when the onset of blindness precedes that ofdeafness, the adaptive plasticity of the cortex, togetherwith the motivation of the patient may recruit the deaf/blind patient into a unique group of excellent implantperformers (Ramsden et al., 1994). This case reportsuggests that multichannel intracochlear implantation hasthe potential for playing a major role in the rehabilitationof certain deaf/blind individuals and that such patients maybe amongst the most worthwhile to consider for cochlearimplantation.Case reportA 39-year-old blind man was admitted to our depart-ment because of profound deafness. He had suffered frombilateral otorrhoea since childhood following radicalmastoidectomy. He lost hearing on the left side due to alabyrinthine fistula resulting from cholesteatoma. Hearingloss on the other side ensued as a result of an end-organlesion as a consequence of labyrinthitis when he was 34years old.At the time of admission, pus and debris were found inboth mastoid cavities despite antibiotic therapy andrepeated aural toilet. The patient had skin lesions and ahistory of recurrent oral ulceration with respiratory andskin allergy. These abnormalities together with eye lesionsresulting in blindness in his early childhood and thepresence of the HLA-DR5 alloantigen, suggested thepatient was suffering from Behcet's disease because of thepresence of four of five diagnostic criteria of the diseaseaccording to suggestion of the International Study Groupof Behcet's disease (1990). The laboratory findings showednormal blood glucose, electrolytes, haematology, and liverfunction tests. An audiogram demonstrated a profoundhearing loss (Figure 1). No cochlear microphonic wasobserved, and there was no response to caloric stimulationwith hot and cold air in either ear. The promontory testhowever, exhibited positive results ie. electrical excitabilityof the acoustic nerve was seen in both sides, subjectivelyconfirmed by bilateral auditory sensation upon stimulation.Ultra high definition computed tomography (CT) scanningshowed normal definition and a normal basal turn of thecochlea on both sides. Previously, he was rejected forcochlear implantation because of the otorrhoea possiblyderiving from an incomplete removal of the secretingmucosa at previous mastoidectomy. In other respects hewas considered a good candidate for a multichanneldevice.SurgeryTo overcome the problem of infected mastoid cavitieshe was submitted to two-stage surgery according to thedescription by Gray and Irving (1995). A post-auricularincision was made to approach the mastoid, the pinna wasdissected and the external auditory canal was transected atthe junction of bony and cartilaginous meatus. Fat wastaken from the anterior abdomen. This was followed by arevision mastoidectomy. All residual middle-ear mucosawas removed together with the infected mastoid air cells.The mucosa of the Eustachian tube was also removed andits lateral wall was drilled away. The lumen was obstructedwith muscle and bone pate. The bony cavity was thenpolished and a piece of silicone rubber sheeting wasFrom the Department of Otolaryngology and 1st Department of Medicine*, Albert Szent-Gyorgyi Medical University Szeged,Hungary and Cochlear AGt, Basel, Switzerland.Accepted for publication: 23 December 1997.169https:/www.cambridge.org/core/terms. https://doi.org/10.1017/S0022215100140216Downloaded from https:/www.cambridge.org/core. University of Basel Library, on 11 Jul 2017 at 08:24:14, subject to the Cambridge Core terms of use, available at170 J. SZILVASSY, J. CZIGNER, J. JORI, F. TOTH, Z. SZILVASSY, J. DE MORA MIESZKOWSKI, J. G. KISS60 125 250RIGHT500 1000 2000 4000 8000 60 125 250LEFT500 1000 2000 4000 8000-20-100102030405060708090100110120-20-100102030405060708090100110120FIG. 1Conventional audiology.Curve A: Pre-operative unaided auditory thresholds. Curve B: Cochlear implant thresholds.1i t .1f rj!—<1/ ^>—-c<y*f1•—Pi i111]• ' ' / .>^ ^! ; !. i l l ! !' T f T!1f' Ay11 { tpositioned over the promontory and round window. Thecavity was obliterated with free abdominal fat. This wasthen followed by blind sac closure of the external auditorycanal according to the description by Gray and Irving(1995).Three months later, the ear was re-opened. Theintended site of the implant was marked and a wideincision made. The site for the implant body was prepared.The fibrous fat was retracted forwards for access. Thepreviously placed silicone disc was elevated and removedfrom over the round window and promontory. This wasfollowed by cochleostomy and implantation of a Nucleus22 ('Cochlear' GmbH Basel, Switzerland) multichanneldevice. All the 22 electrodes were positioned within thecochlea. The device was fixed near the round window. Thewound was closed and the patient was discharged on thethird post-operative day. One week after surgery, thecorrect intracochlear positions of the 22 electrodes wereconfirmed on a conventional transorbital radiograph. Onemonth following implantation the device was activated bythe audiologist.Assessment of acoustic discrimination using the cochlearimplantWe recorded cognitive responses as determined by themost commonly investigated components of cognitiveevent-related potentials such as the mismatch negativity(MMN), the N2b and the P300 to study the centralauditory processes at the use of the implanted device. Thestudy was performed using Dantec Concerto EEG-EPequipment (St Louis, MO) at an experimental setting ofthe so-called 'acoustic oddball paradigm'. The essence ofthis technique is that the patient is asked to calculate thenumber of target or deviant acoustic stimuli in a series ofnon-target or frequent stimuli. The acoustic oddballparadigm was used under passive conditions (the patientread a book for the blind over the investigation period) toverify the MNN and active conditions (the patient wasasked to press a button after he had recognized the deviantstimuli) to confirm the other components (N2b and P300)(Regan, 1989; Oviatt and Kileny, 1991; Kraus et al., 1992).The stimulation protocol included a 1000 Hz frequent and2000 or 500 Hz deviant stimuli.ResultsFollowing switching on of the device, the patientacquired immediate open set speech discrimination abilityand has continued to improve since then. As objectivelyindicated by results obtained from conventional audiology(Figure 1) and the auditory event-related potential study,the patient achieved an acoustic discrimination skillcomparable to that seen in normally hearing subjects.Nevertheless, the implanted patient revealed a somewhatlonger latency period (Figure 2a) with a smaller amplitudecompared to that experienced by normally hearingindividuals (Figure 2b).DiscussionThe results presented show that the deaf blind patientcan benefit greatly from intracochlear implantation of amultichannel device. As indicated subjectively by immedi-ate achievement of open set speech discrimination abilityafter switching on of the device (one month after surgery)and an excellent acoustic discrimination performance atthe same time, the patient has regained his auditorycommunication skills with the outside world almostimmediately following switch on at a baseline level.The first deaf and blind adult patient to receive aNucleus 22 multichannel intracochlear implant in Hungaryunderwent surgery in our department. He is the seconddeaf/blind Hungarian individual having an intracochlearimplant and the first one with Nucleus 22 (the first deaf/blind Hungarian patient to receive an intracochlearimplant is a child implanted with a Med-El device (Ribariet al., 1997). This multihandicapped patient was ofparticular interest for several reasons. Primarily, becauseof his multi-sensory organ failure, secondly, since theprofoundly deafened patient had been suffering frombilateral discharging ear for decades subsequent to radicalmastoidectomy that took place in his childhood. Thus, thepatient, otherwise suitable for cochlear implantation wasrendered inappropriate for surgery because of the lack of asterile, dry protected site for the electrodes. Thirdly, sincehe had a history of several gastrointestinal and respiratorydisorders including gastric ulceration combined withgastrointestinal bleeding and respiratory allergy, wesuspected a systemic disease.https:/www.cambridge.org/core/terms. https://doi.org/10.1017/S0022215100140216Downloaded from https:/www.cambridge.org/core. University of Basel Library, on 11 Jul 2017 at 08:24:14, subject to the Cambridge Core terms of use, available atCLINICAL RECORDS• Normal171100 200 300Latency [ms](a)4 0 0 5 0 0>ituc"a.30 -2520 -15 -105n• Normal• P300m xX• •N2b•MMN l '• ^100 200 300Latency [ms](b)400 500X values indicate individual data of two repetitive determinations with the implanted patient; the black squares denote two repetitivedeterminations with five normally hearing individuals. An amplitude latency relationship for mismatch negativity (MNN) (passivecomponent and active components (N2b and P300).a: 1000 Hz standard and 2000 Hz deviant stimuli; b: 1000 Hz standard and 500 Hz deviant stimuli.FIG. 2Auditory event-related potentials in a deaf/blind patient with a Nucleus 22 multichannel intraocochlear implant. A comparison withnormally hearing subjects.Cochlear implantation of deaf/blind individuals waspreviously thought risky bearing in mind the techniquewas thought to improve lipreading skills in normallysighted patients. This, technique at least in part, explainswhy only a relatively small number of deaf/blind have beenimplanted round the world. Futhermore, the risk ofcochlear implantation is further amplified by the additionalcomplication of chronic bilateral discharging ear excludingimplantation without preceding pre-conditioning surgery.Indeed, our patient had also been refused intracochlearimplantation because of the discharging ears at anotherimplantation centre. We therefore decided to prepare theear for cochlear implantation using the surgery proposedby Gray and Irving (1995). Subsequently, we found nodifficulties in the implantation procedure.It is difficult to state the reason why our patient showedsuch an excellent auditory performance immediately afterdevice activation. According to the experiences of Rams-den et al. (1994) the deaf/blind have been amongst the verybest performers. For an explanation, it is suggested thathuman individuals, similar to several animal species, whohad been blind for years prior to the onset of deafness arebetter able to utilize auditory information than one mightexpect, because of adaptive plasticity of the cortex. Thesituation is different in patients who lose sight and hearingsimultaneously or in those with preceding deafness.Whatever the precise explanation is, we think that deaf/blind patients with preceding blindness can derive greaterbenefit from multichannel intracochlear implantation thanpreviously thought.ReferencesGray, R. F., Irving, R. M. (1995) Cochlear implants in chronicsuppurative otitis media. American Journal of Otology 16:682-686.International Study Group for Behest's Disease (1990)Criteria of diagnosis of Behcet's disease. Lancet 335: 1078.Kraus, N., McGee, T., Sharma, A., Carrell, T., Nicol, T. (1992)Mismatch megativity event-related potential elicited byspeech stimuli. Ear and Hearing 13: 158-164.Oviatt, D. L., Kileny, P. R. (1991) Auditory event-relatedpotentials elicited from cochlear implant recipients andhearing subjects. American Journal of Audiology 1: 48-55.Ramsden, R., Boyd, P., Giles, E., Aplin, Y., Hesketh, A.,Mawman, D. (1994) Cochlear implantation in the deaf/blind. In Proceedings of the 5th International Symposium onCochlear Implants, Surgical Workshop and 1st InternationalAuditory Brainstem Satellite Symposium. Freiburg I. Br.,Germany. (Laszig, R., Marangos, N., eds.) Demeter VerlagGMBH and Co. KG. Balingen, Germany, pp 51-55.Regan, D. (1989) Cognitive processes and motor action. InHuman Brain Electrophysiology (Regan, D., ed.) ElsevierScience, New York, pp 210-250.Ribari, O., Kustel, M., Speer, K., Korpassy, P. (1997)Comparative results with different cochlear implants. ActaOtolaryngologica (Stockh) 117: 169-173.Address for correspondence:Judith Szilvassy, M.D.,Department of Otolaryngology,Albert Szent-Gyorgyi Medical University Szeged,H-6725,Tisza Lajos krt. I l l ,Hungary.https:/www.cambridge.org/core/terms. https://doi.org/10.1017/S0022215100140216Downloaded from https:/www.cambridge.org/core. University of Basel Library, on 11 Jul 2017 at 08:24:14, subject to the Cambridge Core terms of use, available at

Cochlear implantation of a Hungarian deaf and blind patient with discharging ears suffering from Behçet's disease

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