Christian Schild

Comparison of pseudobinaural hearing to real binaural hearing rehabilitation after cochlear implantation in patients with unilateral deafness and tinnitus.

Objective: Up to now, treatment modalities of unilateral deafness consist of no treatment, conventional contralateral routing of signal (CROS), or Bone-Anchored Hearing Aid (BAHA) hearing aid. Cochlear implantation makes a new treatment modality available for patients with single-sided deafness. The aim of this study is to evaluate the use of unilateral electrical stimulation with normal hearing on the contralateral side after a period of 6 months compared with the preoperative unaided situation, conventional CROS, or BAHA hearing aids. Study Design: Prospective design. Setting: Tertiary referral center; cochlear implant (CI) program. Patients: Eleven adult subjects with unilateral deafness of various causes were enrolled in the study. Only those patients were included in whom therapy with CROS hearing aid or BAHA was not successful and in whom the auditory nerve was found to be intact and the cochlea patent for cochlear implantation. Intervention: All subjects were fitted in random order with a BAHA Intenso mounted on the softband/tension clamp or with a CROS hearing aid. After test periods with both devices, the subjects received a CI. Main Outcome Measures: The Hochmair-Schulz-Moser sentence test and the Oldenburg sentence test were used to test speech comprehension in 3 presentation configurations in the unaided situation, with conventional CROS and BAHA hearing aids before cochlear implantation as well as after 6 months with CI. Localization was assessed using an array of 7 speakers at head level in a frontal semicircle. Subjective improvement in daily life was evaluated using the Speech, Spatial and Qualities of Hearing Scale, the Health Utilities Index 3 and the International Outcome Inventory for Hearing Aids questionnaires. Tinnitus distress was measured with a tinnitus scale before and after CI implantation. Results: The results show significant improvement in localization ability as well as in speech comprehension in most presentation configurations with the CI. Especially, there is no negative effect on speech comprehension if the noise is presented to the CI ear and speech to the normal hearing ear. With the CI, the summation and squelch effects are not significant, but a significant combined head shadow effect is seen. Speech, Spatial and Qualities of Hearing results show an overall benefit of wearing the CI compared with the other treatment options. The tinnitus scale revealed a positive effect of CI stimulation in cases of preoperative tinnitus. Conclusion: The results in these patients suggest that cochlear implantation improves hearing abilities in people with single-sided deafness and is superior to the alternative treatment options. The use of the CI does not interfere with speech understanding in the normal hearing ear. Our data suggest that the binaural integration of electric and acoustic stimulation is possible even with unilateral normal hearing.

Unilateral deafness in children: audiologic and subjective assessment of hearing ability after cochlear implantation.

Objectives Recently, several studies have shown that a cochlear implant is a suitable treatment for hearing rehabilitation of adults with unilateral sensorineural hearing loss (UHL), and benefits for speech comprehension in noise and localization have been demonstrated. The aim of this clinical study was to evaluate the benefit of cochlear implantation in children with UHL in comparison to their unaided listening situation. Study design Prospective repeated measures single subject design. Setting Tertiary referral center; cochlear implant (CI) program Patients Three children (4, 10, and 11 yr) with noncongenital UHL resulting from different causes were enrolled in the study. Intervention After extensive consultation with each family and confirming CI-candidacy, each child received a cochlear implant. Main Outcome Measures Open set speech recognition measures in competing background noise and tests of sound localization were performed for unaided preoperative and CI-aided postimplant intervals after 6 and 12 months. The parent and child versions of the Speech, Spatial and Qualities scale (SSQ) were used for subjective evaluation of hearing at preimplant and 12-month postimplant intervals. Conclusion All children consistently use their CI 1 year postimplant. Our preliminary results suggest binaural hearing benefits for speech understanding in noise, localization ability and subjectively perceived hearing ability for school-aged children with UHL. Trends for CI-benefits in younger preschoolaged children are confirmed through subjective assessment reported by the parents. The benefits in hearing performance suggest binaural integration and processing of electric and acoustic stimulation arriving at 2 different ears is possible for children with UHL.

Spectrum of hearing disorders and their management in children with CHARGE syndrome.

Objective: The CHARGE syndrome is associated with ear anomalies and deafness in addition to other malformations. Deformations of the ossicles or aplasia of the semicircular canals, cochlear hypoplasia, hypoplasia or aplasia of the VIIIth cranial nerve and abnormal routing of the VIIth cranial nerve, sigmoid sinus, and emissaries are typical findings. The aim of this study is to explore the feasibility and procedure of cochlear implantation in patients with CHARGE syndrome and to assess the outcome. Study Design: Retrospective case review. Setting: Tertiary referral center; cochlear implant program. Patients: Ten patients with CHARGE syndrome and 3 patients with CHARGE-like syndrome treated in our center due to hearing impairment. Eleven patients were congenitally deaf, 1 patient had progressive hearing loss, and 1 patient had mixed hearing loss. Intervention: Computed tomography of temporal bones and magnetic resonance imaging of the brain; bone-anchored hearing aid surgery, cochlear implantation, rehabilitation results. Main Outcome Measures: Surgical suitability and hearing rehabilitation. Results: We illustrate the management of preoperative diagnostics, surgical planning, and hearing rehabilitation. One patient with mixed hearing loss underwent bilateral bone-anchored hearing aid surgery. Because 2 patients had bilateral aplasia of the auditory nerves, we recommended an auditory brainstem implant. The unilateral cochlear implantation was performed in 9 patients and bilateral in 1 patient. In selected cases, it was helpful to plan the operation using a simulator for temporal bone surgery. Complex malformations, such as in CHARGE syndrome, with an increased intraoperative risk for complications should be facilitated by using intraoperative digital volume tomography-assisted navigation and intraoperative digital volume tomography control of electrode position. The results after CI surgery vary due to the differing extent of additional disabilities such as developmental delay, intellectual delay, and visual impairment. Nine of our patients showed improved responsiveness with the cochlear implant. Open speech comprehension could not be observed in 8 patients, whereas the follow-up period was less than 1 year in 4 patients. The relatively high age of our patients at implantation might be an important factor. Conclusion: Careful planning of the treatment of CHARGE syndrome patients with sensorineural hearing loss can, to a limited extent, lead to auditory benefit without increasing surgical complications. Cochlear implantation is therefore indicated after critical assessment.

Clinical outcome after cochlear implantation in patients with unilateral hearing loss due to labyrinthitis ossificans.

Objectives Cochlear implantation (CI) is the treatment of choice in bilateral labyrinthitis ossificans (LO). The aim of this clinical case study was to evaluate audiologic and subjective outcomes after CI treatment for unilateral hearing loss (UHL) because of LO and to identify optimal timing for treatment. Patients Three subjects (age 40, 54, and 68 yr) with UHL because of LO were enrolled. Duration of deafness was 1.5, 12, and 120 months. Intervention After extensive consultation, testing with conventional contralateral routing of signal hearing aid and bone-anchored hearing instrument, CI candidacy was confirmed and CI surgery performed. Main Outcome Measures Test of open-set speech recognition in background noise and sound localization were performed preoperatively, in unaided and aided conditions, and in the CI-aided condition, at 6 and 12 months postoperatively. Subjective assessment via the Speech, Spatial and Qualities scale (SSQ) and the Tinnitus Visual Analogue Scale was performed at preimplant and 12 months postimplant. Conclusion The data show moderate-to-high hearing benefit after CI in 2 cases and no benefit for the third. SSQ and tinnitus scales show benefit from CI use in both cases. CI treatment should be performed as early as possible, ideally before signs of obliteration are evident. Counseling on all rehabilitation options is important.

A novel dominant and a de novo mutation in the GJB2 gene (connexin-26) cause keratitis-ichthyosis-deafness syndrome: implication for cochlear implantation.

Objective: Keratitis-ichthyosis-deafness (KID) syndrome is a rare congenital disorder, characterized by hyperkeratosis and erythrokeratoderma associated with profound sensorineural hearing loss. Additional concomitant phenomena of the KID syndrome are dystrophic nails, dental abnormalities, scarring alopecia, and vascularizing keratitis. The disorder is caused by mutation in the GJB2 gene (connexin-26), a gap junction protein. The aim of this study was to explore the feasibility and procedure of cochlear implantation in patients with KID syndrome and to assess the genetic causes. Study Design: Retrospective case review. Setting: Tertiary referral center. Cochlear implant program. Patients: We report on 2 cases of KID syndrome with congenital profound hearing loss. A 50-year-old woman with skin necrosis and implant extrusion 5 years after cochlear implantation and a 10-month-old infant girl with bilateral deafness, alopecia, bright light sensitivity, and congenital dermatosis. Intervention: Genetic analysis. Cochlear implantation. Main Outcome Measures: Mutation analysis, surgical suitability, and hearing rehabilitation. Results: We detected a novel heterozygous missense mutation (Ile30Asn) in Patient 1 and a de novo mutation (Asp50Asn) in the GJB2 gene (connexin-26) in Patient 2. To decrease the risk of skin flap necrosis, we describe alternative surgical cochlear implantation techniques with a novel very thin receiver/stimulator (Nucleus CI 513; Cochlear Corp.). The postoperative course of both patients has been without any problems until now. Conclusion: The combination of the cutaneous lesions with visual and auditory impairment demands to diagnose impaired hearing as early as possible. It would be helpful to search for KID syndrome in dealing with patients with deafness, skin lesions of unknown cause, and wound healing problems to choose the right method of surgical treatment and subsequent aftercare.

Kochleaimplantat bei Innenohrfehlbildungen

The radiologic evaluation of the temporal bone in cochlear implant candidates can detect malformations of the inner ear in up to 20% of cases. The aim of our study was to analyze and classify malformations of the inner ear in patients with cochlear implants carried out from 2001 to 2009. Malformations of the inner ear, including malformations of the internal auditory canal were detected in 12.7% of children and 3.4% of adults. Mondini dysplasia was most common and occurred in 45% of cases. The surgical procedure had to be adapted according to the individual malformation. Modification of surgical access, management of intraoperative CSF gusher, choice of electrode array, intraoperative imaging and the use of navigation were the most important factors. Rehabilitation results were generally very positive and corresponded to the expectation depending on the duration of deafness, if no additional handicaps were present.ZusammenfassungDie radiologische Evaluation des Felsenbeins bei Kochleaimplantat-Voruntersuchungen deckt in bis zu 20% der Fälle Fehlbildungen des Innenohrs auf. Ziel der vorgelegten Untersuchung war die retrospektive Analyse und Klassifikation der mit einem Kochleaimplantat versorgten Patienten mit einer Innenohrfehlbildung an der Universitäts-HNO-Klinik Freiburg im Zeitraum 2001–2009. Dabei wurden Fehlbildungen des Innenohrs einschließlich der Dysplasien des inneren Gehörgangs bei Kindern in 12,7% und bei Erwachsenen in 3,4% der Fälle gefunden. Mondini-Dysplasien wurden mit 45% am häufigsten beobachtet. Das chirurgische Vorgehen wurde adaptiert, entsprechend der jeweiligen Fehlbildung. Von Bedeutung sind dabei die Modifikation des operativen Zugangs, das Management des intraoperativen Gusher, die Auswahl der zu implantierenden Elektrode, die intraoperative Bildgebung sowie der Einsatz der Navigation. Die postoperativen Ergebnisse sind als sehr positiv zu bewerten und entsprechen der Erwartung in Abhängigkeit von der Dauer der Taubheit, wenn keine zusätzlichen Entwicklungsbehinderungen bestehen.AbstractThe radiologic evaluation of the temporal bone in cochlear implant candidates can detect malformations of the inner ear in up to 20% of cases. The aim of our study was to analyze and classify malformations of the inner ear in patients with cochlear implants carried out from 2001 to 2009. Malformations of the inner ear, including malformations of the internal auditory canal were detected in 12.7% of children and 3.4% of adults. Mondini dysplasia was most common and occurred in 45% of cases. The surgical procedure had to be adapted according to the individual malformation. Modification of surgical access, management of intraoperative CSF gusher, choice of electrode array, intraoperative imaging and the use of navigation were the most important factors. Rehabilitation results were generally very positive and corresponded to the expectation depending on the duration of deafness, if no additional handicaps were present.

Novel mutation in the homeobox domain of transcription factor POU3F4 associated with profound sensorineural hearing loss.

Background: Hearing loss affects 1 to 3 in 1,000 newborns, with 50% of these cases because of genetic causes. The majority of these are nonsyndromic (70%), and 2% are X linked. So far, 6 different X-linked loci have been mapped, but the causative gene POU3F4 has been identified only for the Locus DFN3. Clinical features of DFN3 often include a mixed, progressive hearing loss, temporal bone anomalies, and stapes fixation. POU3F4 belongs to a subfamily of transcription factors, which are characterized by 2 conserved deoxyribonucleic acid-binding domains, a POU and a HOX domain, both helix-turn-helix structural deoxyribonucleic acid-binding motifs. Several reports have described mutations of POU3F4 in patients with hearing loss and temporal bone abnormalities. In this study, we describe the clinical features and genetic analysis of a male child from a German family with congenital deafness and a novel POU3F4 mutation. Method: Mutational analysis of the affected individual and first-degree relatives was performed using direct sequencing of the coding exon and intron transitions of POU3F4. Result: The patient (II-1) had profound hearing loss, a severely dysplastic cochlea, and cerebrospinal fluid gusher during cochlear implantation. Sequence analysis of all family members demonstrated a novel missense mutation at nucleotide position 973, thymine to adenine (c.973 T>A), p.W325R in the patient (II-1), the mother (I-2), and sisters (II-2, II-3) heterozygous. The father (I-1) is not a carrier of the mutation. Conservation of the affected amino acid residue was seen across a number of different species. Conclusion: We identified a novel mutation in the third helix of the HOX domain of the POU3F4 transcription factor associated with congenital hearing loss.

Comparison of speech discrimination in noise and directional hearing with 2 different sound processors of a bone-anchored hearing system in adults with unilateral severe or profound sensorineural hearing loss.

Objective To evaluate and compare the benefit of a bone-anchored hearing implant with 2 different sound processors in adult patients with unilateral severe to profound sensorineural hearing loss (UHL). Study Design Prospective crossover design. Setting Tertiary referral center. Patients Eleven adults with UHL and normal hearing in the contralateral ear were assigned to 2 groups. Intervention All subjects were unilaterally implanted with a bone-anchored hearing implant and were initially fitted with 2 different sound processors (SP-1 and SP-2). SP-1 is a multichannel device equipped with an omnidirectional microphone and relatively simple digital signal-processing technology and provides a user-adjustable overall gain and tone control with compression limiting. SP-2 is a fully channel-by-channel programmable device, which can be set with nonlinear dynamic range compression or linear amplification. In addition, SP-2 features automatic noise management, an automatic multichannel directional microphone, microphone position compensation, and an implementation of prescription rules for different types of hearing losses, one of them unilateral deafness. After at least 1-month use of the initial processor, both groups were fitted with the alternative processor. Main Outcome Measures Speech discrimination in noise and localization tests were performed at baseline visit before surgery, after at least 1-month use of the initial processor, and after at least 2-week use of the alternative processor. Results Relative to unaided baseline, SP-2 enabled significantly better overall speech discrimination results, whereas there was no overall improvement with SP-1. There was no difference in speech discrimination between SP-1 and SP-2 in all spatial settings. Sound localization was comparably poor at baseline and with both processors but significantly better than chance level for all 3 conditions. Conclusion Patients with UHL have an overall objective benefit for speech discrimination in noise using a bone-anchored hearing implant with SP-2. In contrast, there is no overall objective benefit from SP-1. Depending on the speech-in-noise presentation setting, the difference between objective benefit from SP-2 and SP-1 might be mainly attributed to the new technological features in SP-2 unavailable in SP-1 such as 1) automatic noise management reducing the noise in the speech signal and thus improving the signal-to-noise ratio of the resulting signal on the better ear, 2) programmable multichannel sound-processing and nonlinear dynamic range compression offering considerably greater control over signal amplification compared to SP-1, and 3) implementation of a prescription rule for unilateral deafness addressing the specific amplification needs of patients with UHL by reducing amplification in the low frequencies and applying additional gain in the high frequencies. Sound localization is poor but better than chance level in the unaided condition as well as in both bone-anchored hearing system–aided conditions.

Langzeitergebnisse nach Kochleaimplantatversorgung bei Kindern

The treatment of deaf and hearing-impaired children with cochlear implants has been established for several years. Nonetheless, no long-term results exist for studies of a representatively large number of children in the German-speaking area. These are necessary in order to formulate prognoses regarding the development and results of children undergoing implantation at various ages. In a retrospective study, we assessed the data of 156 children with various implantation ages and a minimum follow-up period of 5 years for whom speech and audiological data (Oldenburg Sentence Test, Freiburg words/numbers test) were available. Our findings confirm the assumption that early-implanted children (<2 years) achieve the best speech-comprehension results. For this reason, support for a sufficient universal neonate hearing screen should be emphatically given so that implantation, after a hearing test phase, can be targeted in the first year of life. The surgical, anesthesiological, and rehabilitation conditions must be fulfilled, and surgical experience is required for operation on infants and small children.

[Insertion results for Contour™ and Contour Advance™ electrodes: are there individual learning curves?].

The aim of our study was to evaluate results of insertion following cochlear implantation with Contour™ and Contour Advance™ electrode arrays in adult patients and to analyze individual insertion results for three experienced surgeons. We performed a retrospective analysis of postoperative 3D volume tomography results in 223 adult patients. The intracochlear electrode position was evaluated to be in scala tympani, scala vestibuli or with a dislocation from one scala to the other. Surgical methods were analyzed and assigned to the different surgeons. We observed a significant increase for scala tympani insertions from initially 33% to 84% and a reduction in dislocations from scala tympani to scala vestibuli from 71% with the Contour™ electrode to 22% with the Contour Advance™ electrode. Results for the different surgeons varied individually with regard to scala tympani insertion rates and dislocation rates over time. 3D Volume tomography offers an important method for postoperative quality control following cochlear implant surgery. The intracochlear electrode position could be determined in all cases. We were able to identify individual learning curves for insertion results. Controlling the insertion quality serves as a feedback of surgical results and may be helpful for improving surgical quality and thus rehabilitation results.ZusammenfassungZiel der Untersuchung war die Evaluation der Insertionsergebnisse nach Cochleaimplantation von Contour™- und Contour-Advance™-Elektrodenträgern bei erwachsenen Patienten sowie die Verfolgung der individuellen Insertionsergebnisse dreier erfahrener Chirurgen. Anhand der routinemäßig durchgeführten postoperativen 3-D-Volumentomographie bei 223 erwachsenen Patienten mit Lagebestimmung der Elektrode in der Cochlea (Scala tympani, Scala vestibuli, Dislokation von einer in die andere Scala). wurde retrospektiv das chirurgische Vorgehen analysiert und den jeweiligen Chirurgen zugeordnet. Die Scala-tympani-Insertionen stiegen von initial 33 auf 84% signifikant an. Mit Verwendung der Contour-Advance™-Elektrode sank gleichzeitig die Dislokationsrate aus der Scala tympani in die Scala vestibuli von initial 71% mit der Contour™-Elektrode auf 22%. Für die einzelnen Chirurgen zeigten sich individuelle Unterschiede in Bezug auf die Scala-tympani-Insertionsraten und die Dislokationsraten im Untersuchungszeitraum. Mit der 3-D-Volumentomographie ließ sich die Elektrodenposition in allen Fällen evaluieren, sodass ein wertvolles Instrument zur Qualitätskontrolle vorliegt. Gleichzeitig stellten sich individuelle Lernkurven dar. Die Kontrolle der Insertionsqualität ist notwendig, um durch ein Feedback der Insertionsergebnisse die chirurgische Qualität verbessern zu helfen und konsekutiv die Rehabilitationsergebnisse zu verbessern.AbstractThe aim of our study was to evaluate results of insertion following cochlear implantation with Contour™ and Contour Advance™ electrode arrays in adult patients and to analyze individual insertion results for three experienced surgeons. We performed a retrospective analysis of postoperative 3D volume tomography results in 223 adult patients. The intracochlear electrode position was evaluated to be in scala tympani, scala vestibuli or with a dislocation from one scala to the other. Surgical methods were analyzed and assigned to the different surgeons. We observed a significant increase for scala tympani insertions from initially 33% to 84% and a reduction in dislocations from scala tympani to scala vestibuli from 71% with the Contour™ electrode to 22% with the Contour Advance™ electrode. Results for the different surgeons varied individually with regard to scala tympani insertion rates and dislocation rates over time. 3D Volume tomography offers an important method for postoperative quality control following cochlear implant surgery. The intracochlear electrode position could be determined in all cases. We were able to identify individual learning curves for insertion results. Controlling the insertion quality serves as a feedback of surgical results and may be helpful for improving surgical quality and thus rehabilitation results.