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Here, we describe the surgical technique for implanting a new, active, transcutaneous bone conduction hearing aid. The implant technology is based on a system that has been in use reliably since 2012. The geometry of the new implant has been adapted based on experience with previously introduced implants. The surgery was feasible, standardized, and safe. Due to the optimized geometric design that improved the bone fit, it is not necessary to use specialized, detailed preoperative planning, except in challenging anatomical conditions; e.g., in young children, malformations, poor pneumatization, or after a canal wall down mastoidectomy.

Implantation of the Bonebridge (MED-EL, Innsbruck, Austria), an active semi-implantable transcutaneous bone conduction hearing system, involves the risk of impression or a lesion in intracranial structures, such as the dura or sigmoid sinus. Therefore, determining the optimal implant position requires careful preoperative radiological planning.The aim of this study was to provide an overview of the possibilities for preoperative radiological planning for the Bonebridge implantation and to evaluate their indications and feasibility.A systematic literature search was conducted in the PubMed/MEDLINE database for all studies with preoperative planning or implant placement as the primary endpoint or that secondarily mention preoperative planning.Of 558 studies, 49 fulfilled the inclusion criteria. In 18 studies, preoperative planning and floating mass transducer (FMT) placement were the primary endpoints, whereas in 31 studies, preoperative planning was described secondarily.There are both freely available and commercial tools involving different time commitments for preoperative three-dimensional (3D) planning and intraoperative transfer. Preoperative 3D planning can increase the safety of Bonebridge implantation.

Bone conduction hearing aids can be worn as noninvasive devices using a clip or soft band that exerts pressure on the skin, or they can be surgically implanted. ADHEAR (MED-EL GmbH, Innsbruck, Austria) is a novel noninvasive bone conduction hearing aid that is attached behind the ear using an adhesive adapter and does not exert pressure on the skin. ADHEAR is indicated for patients with conductive hearing loss and normal inner ear function. The aim of this study was to evaluate the achievable hearing improvement with ADHEAR.Twelve subjects with normal hearing participated in this study. To mimic conductive hearing loss, the participants' ear canals were occluded unilaterally with a foam ear plug. The resultant conductive hearing loss was assessed with pure tone air- and bone-conduction threshold audiometry. Hearing ability was tested with and without ADHEAR via free-field tone audiometry, number perception, and monosyllable perception, with the contralateral ear plugged depending on test requirements.Using ADHEAR, the free-field hearing threshold improved by 13.7 dB at 500 Hz, by 17.9 dB at 1 kHz, by 17.2 dB at 2 kHz, and by 9.8 dB at 4 kHz. In the higher frequencies, a significant pure-tone gain of 14.4 dB at 6 kHz and of 16.5 dB at 8 kHz was observed. Number perception with ADHEAR was mean 69.2% at 35 dB, 97.9% at 50 dB, 100% at 65 dB, and 100% at 80 dB. Monosyllable perception with the ADHEAR was mean 35.0% at 35 dB, 72.3% at 50 dB, 93.5% at 65 dB, and 98.8% at 80 dB.Hearing performance was significantly better with ADHEAR under all test conditions except those where maximum perception was already achieved without ADHEAR.

The evaluation of results after middle ear reconstruction has been mainly based on functional parameters. In clinical practice as well as in otological research, the pure tone audiogram represents the gold standard in the assessment of the postoperative outcome. In order to assess the patient's subjective outcome, outcome analyzes focus increasingly on the health-related quality of life (HRQOL). However, the evaluation of HRQOL requires reliable and validated measuring instruments. A modest number of validated questionnaires for determination of the disease-specific HRQOL in patients with chronic otitis media and/or conductive hearing loss are currently available. Three of seven available questionnaires were developed and validated in the German-speaking countries, the Zurich Chronic Middle Ear Inventory 21 (ZCMEI-21), the Chronic Otitis Media Outcome Test 15 (COMOT-15) and the Stapesplasty Outcome Test 25 (SPOT-25). In this review, all seven available disease-specific measuring instruments as well as the generic questionnaires, which were used in previous clinical trials, are explained and current findings of quality-of-life research in patients with chronic otitis media and/or conductive hearing loss are presented.

An instrument to measure vibration in the middle ear needs to be sensitive enough to detect displacement on a nanometer scale, yet not affect the vibration itself. Numerous techniques have been described in the literature, but laser Doppler vibrometry (LDV) has nowadays become established as the standard method in hearing research.This article aims to present possible clinical applications of an LDV system in otology.A commercially available single-point vibrometer was used. Measurements were carried out both with the sensor head mounted on an operating microscope and as a handheld device with the sensor head manually inserted in the ear canal. For the latter, a custom-made unit containing an electrically tunable lens was attached to the sensor head. Middle ear vibrations were measured in a temporal bone model as well as in patients during and after implantation of a Vibrant Soundbridge (VSB; MED-EL Corp., Durham/NC, USA).Different types of middle ear pathologies can be distinguished by the frequency response of the umbo. The LDV technique can be used for intraoperative quantification of the coupling quality of the VSB's Floating Mass Transducer (FMT; MED-EL) to the ossicle chain during VSB implantation. Postoperatively, the method serves as a follow-up testing tool if a deterioration in aided hearing threshold occurs. The measurement can reveal changes in the umbo transfer function, e. g., due to middle ear scarring or dislocation of the FMT.Many clinical questions in otology can be addressed by LDV. However, due to the high acquisition costs of an LDV system, the relatively large instrumental setup, and the large inter-ear variability of middle-ear function, the technique has not (yet) become established in clinical routine.

Isolated fracture of the handle of the malleus is a rare cause of conductive hearing loss and represents a challenge for the otolaryngologist in terms of past medical history, diagnostics, and therapy.

Patients with air-bone gaps or combined hearing loss that cannot be corrected by tympanoplasty can be treated with bone conduction hearing aids. The disadvantages of conventional and percutaneous systems are, on one hand, the obvious external fixation components and on the other hand, the biological and psychosocial problems of open implants. This project was therefore set up to develop a semi-implantable, magnetically anchored transcutaneous bone conduction device, introduce it into clinical application and follow-up the results.The principle of this bone conduction device is the magnetic coupling of an external vibrator via implanted double magnets. After extensive laboratory tests, this method was introduced into the clinic in 2006. Following the initial pilot study, 184 implantations in 143 patients have been performed in Recklinghausen since 2008. Long-term evaluation of 20 congenital atresia patients treated with these devices was possible.Worldwide, more than 3000 of these devices have been implanted. The operative implantation technique is relatively simple. With the new "upside down technique", bone removal is no longer necessary. The 2.6-mm thin implants are hardly noticeable. The hearing improvement is similar to that of other bone conduction hearing aids.This semi-implantable transcutaneous bone conduction hearing device is another option for patients with air-bone gaps, combined hearing loss or single-sided deafness.

Implantable hearing aids are not only gaining importance for the treatment of sensorineural hearing loss, but also for treatment of mixed hearing loss. The most frequently used active middle ear implant is the Vibrant Soundbridge (VSB) system (Fa. MED-EL, Innsbruck, Österrreich). Following widening of the spectrum of indications for the VBS, various new coupling systems have been established. Based on the literature, available petrosal bone investigations and finite element model (FEM) calculations, this article summarizes the current knowledge concerning mechanical excitation by the VSB. Important concomitant aspects related to coupling, transmission and measurement are also discussed.

Active implantable hearing devices were primarily developed for sensorineural hearing loss. The vibrator coupling mechanisms were oriented towards normal middle ear anatomy and function. The aim of this project was to modify the only fully implantable hearing device with an implantable microphone for application in congenital auricular atresia, Carina™, and to introduce the modified device into the clinic. A special prosthesis was developed for the transducer and its individual coupling achieved by a special cramping system. The system was implanted in 5 patients with congenital auricular atresia. Audiological results were good; with patients' hearing gain exceeding 30 dB HL. Anatomic limits to the system's indications and technical drawbacks are also discussed.

By virtue of direct bone conduction, percutaneous bone-anchored hearing implants offer a high level of wearing comfort, as well as audiologically superior signal transmission due to less dampening. Over the years, titanium implants have been optimized and the surgical technique developed into a minimally invasive intervention without soft tissue reduction. This study aims to investigate the success rates of the various percutaneous implant systems.This retrospective study includes 191 patients who received a total of 283 percutaneous titanium implants for bone conduction hearing systems during the period from 01.01.1989 until 31.12.2013. Patient age ranged from 2 to 81 years (mean 36 years). The mean follow-up duration was 5.2 years.The overall osseointegration success rate was 92.6% and ranged from 90.5 to 100% for the various implant systems (p = 0.6). For children and adolescents, the success rate was 86.8%, compared to 95.2% in adults (p = 0.023). Classical soft tissue reduction was received by 185 patients, mainly via the dermatome technique. The linear incision technique was used in 3.8% of cases and the technique without soft tissue reduction in 3.7% of cases. Revision surgery for soft tissue problems was performed in 4.2% of cases.Success rates in adults were significantly higher than those in children and adolescents. Although success rates improved with the development of new systems, this did not reach statistical significance. Minimally invasive surgery without soft tissue reduction is considered state of the art.

Because of the anatomy of the mastoid and the size of the actuator, positioning of the Vibrant Bonebridge B-FMT can be difficult without prior evaluation of the individual computed tomography (CT) scan of the temporal bone. Development of a user-friendly CT data viewer to enable positioning of the B-FMT in the temporal bone model, whilst identifying individual, potential anatomic conflicts and offering possible solutions could provide a useful tool for preoperative positioning.Aim of the study was to define the requirements of a Vibrant Bonebridge viewer and construct a prototype.Based on a ZIBAmira software version and inclusion of a B-FMT model upon creation of a model of the temporal bone-which allows the intuitive estimation of individual, anatomic conflicts-a Vibrant Bonebridge viewer was constructed.The segmentation time of the individual digital imaging and communications in medicine (DICOM) data set is about 5 min. Positioning within the individual three-dimensional temporal bone model allows quantitative and qualitative estimation of conflicts (sigmoid sinus, middle cranial fossa) and determination of a preferred position for the B-FMT. Lifting of the B-FMT can be simulated with the help of a virtual washer.The Vibrant Bonebridge viewer reliably allows simulation of B-FMT positioning. The clinical value of the viewer still has to be evaluated.

Otitis media with effusion (OME) as the most common cause of hearing loss in childhood plays an important role in the follow-up after failed newborn hearing screening (NHS). The introduction of the NHS allows OME to be diagnosed and treated in the first months of life.In 715 children referred to the Department of Phoniatrics and Pedaudiology of the Ear, Nose, Throat University Hospital of Magdeburg during the period 2006-2010, the prevalence and therapy process of OME during follow-up could be determined.OME was diagnosed in 16 % of the patients. Spontaneous resolution was observed in 37 % of the cases, while 46 % of the children were treated surgically. A substantially increased risk for persistent OME was observed in children with craniofacial dysmorphia or cleft palate.Using NHS, OME can be diagnosed and treated early, thus, preventing potential problems in the linguistic, social and intellectual development of children.

The objectives of this study were to compare a German version of the Glasgow Benefit Inventory (GBI) with the original English version and to describe quality of life following stapes surgery.Audiometry and a questionnaire on handicap in various listening situations were used to assess 36 patients with otosclerosis before and 6 months after stapes surgery. The GBI was used to estimate the change in quality of life following surgery.Postoperative air-bone gap closure was10 dB in 71% of patients. The postoperative air conduction threshold was30 dB in 48% of patients. Using the GBI, the mean benefit score was 28 and the general benefit score 42. The social support and physical health scores were both zero. Where the postoperative improvement in air conduction was15 dB, a significant reduction in handicap in everyday life, watching TV, listening to the radio and making telephone calls was seen.The German version of the GBI showed an improvement in quality of life in various everyday situations following stapes surgery.

Strictly speaking, implantable hearing aids are technical systems that process audiological signals and convey these by direct mechanical stimulation of the ossicular chain or cochlea. They have certain benefits over conventional hearing aids in terms of wearing comfort and general acceptance. As current studies lack convincing audiological results, the indications for implantable hearing aids are primarily of medical or cosmetic nature. To date, three systems are available in Germany: Vibrant Soundbridge®, Carina®, and Esteem®. Because the performance of the different implantable and nonimplantable hearing systems together with various surgical procedures are currently undergoing major changes, audiological indications may also develop in the future.

Bone-anchored hearing aids provide a therapy option for patients with conductive and mixed hearing loss, with the possibility of audiological rehabilitation. Test rod and tension headband offer the patient a preoperative impression of their postoperative hearing. The aim of this study was to evaluate the tools available for preoperative assessment of candidates for bone-anchored hearing aids and to ascertain predictive audiometric values.Following implantation of a BAHA Compact system, sound and speech audiograms were performed in each of 16 patients with the bone-anchored BAHA device and with test rod and tension headband.Both with the BAHA and with the test devices, closure of the air-bone gap occurred and resulted in a clear improvement in hearing threshold and speech perception. The threshold increase with the BAHA was 9 dB greater on average (mean) than that measured with the test rod and the tension headband. Examinaation of speech perception indicated a mean advantage of 14-20% for the anchored BAHA system over the tension headband in monosyllabic testing.Preoperative testing before providing a BAHA system is a good way of predicting what level of hearing and speech perception can be expected after implantation.

Stapes surgery is remarkably different from regular middle ear surgery. The inner ear space has to be opened and the risk of postoperative deterioration of hearing and deafness is much higher. Peculiarities involve submerged parts of the foot plate into the vestibulum, the overhanging facial nerve with or without bony covering, bleeding from the mucosa, and problems involving the chorda tympani. Labyrinthine reactions during or post surgery are common. Important is the question of whether or when the piston should be removed. Rare cases such as a gusher with a wide connection between perilymph and CSF space are a major challenge in stapes surgery.

Patients with high-grade microtia and atresia require a sophisticated and specific treatment. Apart from the plastic reconstruction of the auricle, in some cases hearing rehabilitation is medically indicated or is desired by the patients. The long-term results of simultaneous middle ear reconstruction with tympanoplasty are often inadequate owing to a persisting air-bone gap, and new techniques in hearing rehabilitation are needed for these patients.We present three cases of unilateral atresia to illustrate a combined approach integrating hearing rehabilitation using the active middle ear implant Vibrant Soundbridge (VSB) into plastic auricular reconstruction. The VSB was attached to the stapes suprastructure via the titanium clip in two of these cases and in the third case a subfacial approach was used to attach it directly to the membrane of the round window.The air-bone gap was reduced to 17 dB, 14 dB and 0.25 dB HL. In free-field speech recognition tests at 65 dB SPL the patients achieved 100%, 90% and 100% recognition with the activated implant. No postoperative complications such as facial nerve paresis, vertigo or inner ear damage were found.The integration of active middle ear implants in auricular reconstruction opens up a new approach in complete hearing rehabilitation. The additional implantation of the VSB does not have any negative effect on the healing process or the cosmetic outcome of the auricular reconstruction.

In very rare cases, acute hearing loss can be caused by a fractured long process of the malleus. Such fractures can be due to head traumas, direct injuries of the tympanic membrane or barotraumas. Clinical findings are: abnormal mobility of the manubrium mallei during the Valsalva maneuvre or pneumomassage of the ear drum, conductive hearing loss, abnormal high compliance in the type A tympanigram. We report on a 48 year old female patient who showed typical symptoms and clinical findings, and discuss possible pathogenic factors. In accordance with the literature, we presume that negative pressure in the external ear canal, caused by a rapidly extracted finger (!), might be responsible. At the very onset of hearing loss, the patient noticed a high frequency tinnitus in the affected ear. Surgically, we tried to re-fix the manubrium by splinting it and the adherent parts of the tympanic membrane with cartilage.

The rehabilitation of patients having severe malformation of the auricle with congenital auricular atresia requires plastic surgery and audiologic treatment. After classifying these malformations, various options involving hearing aids and surgery are presented. The main focus is on our new technique of combined auricular reconstruction with construction of the external ear canal and tympanoplasty, the so-called atresia-operation. It is characterised by three steps combining plastic and otologic surgery with prefabrication of the tympanic membrane and the external ear canal. Finally, our current rehabilitation concept for these patients is presented.

The application of cartilage in tympanoplasty has been generally accepted, because cartilage as a bradytrophic tissue allows stable and functionally reliable reconstruction of the eardrum even in difficult pathological conditions (such as subtotal defects, tympanosclerosis etc.). A special surgical technique using small cartilaginous chips for the reconstruction of the eardrum has been developed by J. Heermann, who introduced it as Palisade Cartilage Tympanoplasty (PCT). Although being increasingly applied in otosurgery, this technique has to date neither been evaluated regarding morphological and hearing results nor regarding its combination with titanium ossicular reconstruction prostheses.Therefore we reviewed 84 of 94 ears (92 patients, 58 female, 34 male) 12 to 36 months after PCT.A recurrent defect was seen in 2 ears (1 adhesive otitis, 1 subtotal defect). There were no extrusions of prostheses. Preoperatively an ear-bone-gap of 0-10 dB was seen in 2 ears, 11-30 dB in 48 and 31-59 dB in 34 ears. Postoperatively the corresponding numbers were 25, 50 and 9 ears.The low rate of recurrent tympanic membrane defects (2.4%) shows that palisade cartilage tympanoplasty is particularly appropriate for the management of difficult indications in middle ear surgery. Further, it could be demonstrated that the PCT can be combined safely with titanium ossicular reconstruction prostheses. Regarding postoperative hearing results the negative preselection of pathological conditions has to be considered.

The literature gives hardly any information about the benefits for children of using a bilateral bone-anchored hearing aid (BAHA) as opposed to a bilateral conventional bone conducting hearing aid.Within a period of 12 years, three children were selected for treatment with bilateral BAHA. At the time of surgery, the children were aged between 8 and 10 years. Two of the children suffered from Franceschetti syndrome and one child from Goldenhar's syndrome. The clinical course of these three patients is presented.In all cases, treatment with BAHA was beneficial according to subjective and objective criteria despite localized inflammatory complications in two of the three cases.The bilateral use of BAHA should be considered more frequently as an alternative to conventional bone conducting hearing aids even for children.

Appearance of an anticholinergic syndrome after treatment with drugs in therapeutic dosages is seldom reported in the literature. Based on a case report, the development and course of an anticholinergic syndrome after treatment with dimenhydrinate are described. The drug was given due to different symptoms such as vertigo and vomiting after surgery. The anticholinergic syndrome could successfully be treated with physostigmine.

A case of hyperacusis after tympanoplasty is presented. A 62-year-old woman experienced unilateral conductive hearing loss for about 60 years after antrotomy in infancy. Neurological or otoneurological symptoms were not evident. Tympanotomy showed a missing incus with discontinuity of the chain. Reconstruction was performed by interposition of a partial ossicular replacement prosthesis (PORP). The postoperative audiogram revealed minimal perceptive hearing loss in the high-frequency field in the operated ear. Several weeks after middle ear surgery, the patient complained of hyperacusis on the operated side, which persisted for more than 2 years. To alleviate the unpleasant sensations, an ear plug was used by the patient. In spite of the asymmetric hearing loss, no late onset auditory deprivation could be diagnosed. The pathophysiological causes of the hyperacusis have not yet been clarified. Possible reasons are discussed.

The presence of the internal carotid artery in the middle ear is a rare but known vascular anomaly. A blue-reddish mass behind the tympanic membrane, hearing loss and a tinnitus that is synchronous with the pulse are the typical symptoms and should lead to a correct diagnosis. The diagnostic procedure includes high resolution CT scans with or without contrast or MRI. Possible methods of therapy include embolization, stent implantation or balloon occlusion of the internal carotid artery but are seldom indicated clinically because of the high rate of side-effects. However, regular followup examinations must be performed.

The measurements of transitory evoked otoacoustic emissions (TEOAE) and auditory brainstem responses (ABR) are widely used in objective audiometry for the diagnosis of conductive or sensorineural hearing losses. In some cases only one of these signals is required for a complete diagnosis, while other cases may require both methods to define findings. With conventional equipment the measurement of TEOAE and ABR is performed with different devices at different times. Devices for simultaneous recording of both signals are currently not available or described, although the physiological circumstances and apparatus requirements would favor such an approach. In the present work a prototype for the simultaneous measurement of TEOAE and ABR is presented and its application tested in 33 normal-hearing adults. The equipment used was based on a general purpose laboratory computer connected to an acoustic stimulator and a dual-channel data acquisition system. Stimuli were composed of click sequences for the cancellation of linear signal components and were presented by an ear canal probe (Otodynamics) which also picked up the microphone signal within the outer ear canal. The EEG activity containing the ABR was recorded through surface electrodes fixed at the patient's vertex and mastoid. Acoustic and electric signals were processed simultaneously, resulting in three independent records representing a non-linear TEOAE and the low and high level ABR. The main advantages of the new approach are an improvement in information output and enhancement in the accuracy of determining the site and extent of a hearing impairment.

To rehabilitate most cases of conductive hearing loss closure of ear drum perforations and rebuilding of the ossicular chain can be performed. Due to the great number of biocompatible bone substitute materials available it is occasionally difficult for the surgeon to choose the most favorable substitute. Autogenous structures (ossicles, cortical bone, cartilage) and allogenous tissues (ossicles, cortical bone, cartilage, dentin) are possible bone replacement materials. Xenogenic tissue is currently not used in middle ear surgery. Ionomer cement is a hybrid material for replacement of bone but does not fit direct classification of the various classes of alloplastic materials in current use: that is, metals (gold, steel wire, platinum, titanium), plastics (polyethylene, polytetrafluorethylene) and ceramics (ceramic oxide, carbon, calcium-phosphate ceramic, vitreous ceramic). For restoration of the sound conductive apparatus preference is given to autogenous ossicles because cortical bone is resorbed and cartilage weakens over time. Most surgeons do not use allogenous tissue, because of the possible transmission of such infectious disease as immunodeficiency syndrome or Creutzfeldt-Jakob disease. Only dentin deserves special attention as a possible bone substitute in the middle ear because its form can be preserved during sterilization. Based on the observations available to date, it becomes apparent that titanium implants hold greater promise than gold. Form-stable synthetic materials are not generally recommended due to foreign body reactions which have been confirmed by many investigators. Ceramic materials (e.g. ceramic oxide, carbon, calcium-phosphate ceramic, glass ceramic) are well tolerated in the middle ear and have also proved to be useful over time. Hybrid bone substitute ionomer cement is easily workable and well integrated, showing a good functional outcome. For many years good results in otosclerosis surgery have been achieved with a prosthesis made of platinum-wire and Teflon. Short-term follow-up periods hold great promise with pistons made of gold. Autogenous ossicles, ionomer cement and recently titanium protheses--as far as usable--are employed by the author for reconstructing the middle ear. For the time being platinum-Teflon prostheses and gold are used in otosclerosis surgery.

A case report is presented of a 54-year-old woman with tinnitus synchronous with her pulse and an ipsilateral conductive hearing loss. Otoscopy showed a pulsatile structure behind the right eardrum. Imaging with high-resolution computed tomography of the temporal bone showed an enlarged jugular vein bulb. Magnetic resonance imaging could not be performed because of an implanted pacemaker. Since a glomus jugulare tumor could not be excluded right diagnostic tympanoscopy was performed and revealed a high jugular bulb that filled nearly a third of the tympanum.

Conductive and sensorineural hearing losses are of genetic origin in 20% to 60% of cases. In general, genetic abnormalities are more often expressed as a sensorineural hearing loss than as a conductive hearing loss. At present several genes for sensorineural hearing loss have been isolated. The most common genetically transmitted forms for isolated conductive hearing losses are otosclerosis and small malformations of the ossicles. To date no genes responsible for these deformations have been isolated. We present a family with four siblings having conductive hearing losses caused by ossification of the stapedial tendon. This finding is suggestive of an autosomal recessive inheritance. The early diagnosis of an hereditary conductive hearing loss contains the possibility for permitting normal development of speech.

With the aid of a mechanical middle ear model (MMM) the sound transmission properties of different middle ear implants were investigated. Input of the MMM involved a broad-band signal from 100 to 5000 Hz that was supplied by a miniaturized loudspeaker. Displacement of an artificial stapes footplate was measured by a fiberoptic probe. The transfer functions of four different total ossicular replacement prostheses (TORPs) of different materials and shapes were compared. Three of the devices revealed similar transfer functions which corresponded to the typical curve of the normal middle ear. One of the prostheses demonstrated a high-frequency deterioration of approximately 5 dB. This effect was explained by a 3- to 6-times higher mass of the implant when compared to the others. Altogether, the weight of the prosthesis seems to have the most marked impact on sound transmission to the inner ear, whereas stiffness of the implant itself is less crucial as long as it can be regarded as a rigid body.

A complete battery of audiometric methods is required for the differential diagnosis of different hearing disabilities (including puretone audiometry, impedance, stapes reflex, speech audiometry, brainstam evoked response audiometry, otoacoustic emissions, etc.). In many cases, a comprehensive diagnosis is not possible. Here we describe a new technique based on a laser-Doppler vibrometer that has the potential for non-invasive diagnosis not only middle ear disease but also cochlear pathologies. Disturbance of cochlear function can be ascertained because the input impedance of the cochlea acts as a mechanical load on the middle ear and therefore influences motion of the umbo. In the present study vibration of the umbo and eardrum were measured with a commercially available laser-Doppler vibrometer coupled directly into a standard surgical microscope. The use of the microscope allowed non-invasive measurements of vibrations without having to introduce reflecting material onto the tympanic membrane. Sound pressure was measured with a calibrated probe microphone placed near the tympanic membrane. The displacement response and the specific acoustic impedance of the umbo were calculated from the velocity and sound pressure measured. For normal hearing subjects, the amplitude of the umbo's displacement for frequencies from 0.1 kHz to 1 kHz was 1 nm at 60 dB SPL and decreased with a slope of 6 dB/octave for frequencies between 1 and 5 kHz. A strong correlation was found between the specific acoustic impedance of the umbo and hearing thresholds for hearing-impaired subjects (having otosclerosis or sensorineural hearing losses). The frequency response of the umbo proved to be a means for evaluating the function of both the middle ear and the cochlea under pathological conditions. The measurement technique described is also suitable for intraoperative investigation of the frequency response of the opened middle ear, as well as for the in situ frequency response of partial and total ossicular replacement prostheses.

We reviewed 192 patients who had been treated for chronic otitis media. All operations were carried out at the Department of Otolaryngology, University of Tübingen. No patient had a previous ear operation and revision operations were excluded. The observation period varied from a minimum of 1 year to a maximum of 4 1/2 years. The ossicular chain was partially destroyed in 43 ears (22.4%). Ossiculoplasty was performed using autologous ossicles. An inens was used in 31 ears and a malleus in 12 cases. The overall failure rate was 20.8%. Most recurrent perforations were found in middle-aged patients. Children had only a 14% incidence of recurrent perforations. Fascia was the material associated with the highest failure rate (28.6%). After using perichondrium 6.8% of the cases had recurrent perforations, whereas the perichondrium-cartilage transplant was not successful in 4.8%. Overall, 62.7% of the patients were found to have an air-bone gap of 10 dB or less at 1.5 kHz 3-6 months after surgery. An air-bone gap of 20 dB or less was found in 91.2% of the patients. The main problem seen in the patients with chronic otitis media was not reconstruction of the ossicular chain but a lasting closure of the tympanic membrane. The perichondrium-cartilage transplant permitted the best results and is now recommended especially for patients with unfavorable middle ear conditions. A long-lasting closure of the tympanic membrane was also found in children (or = 15 years of age). For this reason we also recommend an early operation in order to allow children to lead a normal life.

Active hearing implants have been developed to varying degrees for conductive hearing loss as well as for sensorineural hearing loss. Implants for conductive hearing loss match impedance transformation by the middle ear. They will be referred to as ITI (impedance transformation implants). Three partial ITIs have been developed for routine clinical use: the Swedish transcutaneous BAHA, the American subcutaneous AUDIANT, and the Japanese P-MEI. Of greater importance with respect to the number of patients are electronic implants for sensorineural hearing loss. These implants are designed to replace parts of the function of the cochlea amplifier (CA). Therefore, in this study, they will be called CAI (cochlea amplifier implant). The CAI consist of four parts: (1) transducer, (2) microphone, (3) control unit, and (4) battery. A CAI for routine clinical use does not yet exist. Two transducer principles have thus far been developed for use in CAIs: the electromagnetic (EM) and the piezoelectric (PE) principle. Most of the transducers that have been described are EM transducers. The American Maniglia implant and the American floating mass transducer have been tested in humans. Both belong to the category of high energy consuming (HEC) implants with a limited frequency range that does not contain the whole speech spectrum. This is in contrast to the Canadian electromagnetic Fredrickson-HEC implant which is capable of transmitting broad band signals of up to 10 kHz. All ot he HEC-EM transducers lack an implantable microphone and an implantable battery. The German CAI, one of the piezoelectrical implants, was recently implanted acutely in humans. It consists of a piezoelectrical, ossicle coupled, low energy consuming (LEC) transducer, as well as an implantable microphone. It allows a broadband signal of up to 10 kHz, yet at a considerably lower level of energy.