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The endoscopic approach to stapes surgery affords unique advantages but is not without its specific challenges. The following reviews the equipment and surgical steps required to perform endoscopic stapes surgery safely and effectively, highlighting tips and potential points of failure through a series of case examples.

This article is an overview of the care of patients requiring revision surgery for otosclerosis. Preoperative evaluation of the patient including surgical history, audiologic results, and physical findings is discussed, and the causes of failure of primary surgery are reviewed. A discussion of evidence-based surgical technique and postoperative care then follows.

Lasers were introduced as an atraumatic modality for accomplishing several of the crucial steps in otosclerosis surgery. Advances in laser technology have spurred coevolution of refinements in the technique of the operation. Several varieties of laser systems are available to suit individual preference and to augment a surgeon's armamentarium; however, a clear advantage in terms of surgical outcome or patient safety remains to be demonstrated.

Stapedectomy and stapedotomy represent the state-of-the-art surgical procedures in addressing the conductive hearing loss caused by otosclerosis. Their high rates of success and long-term stability have been demonstrated repeatedly in many studies. In comparing the short- and long-term results of the 2 procedures, it is evident that stapedotomy confers better hearing gain at high frequencies and lower complication rates. Modified stapes mobilization procedures may represent the next major development in stapes surgery in a selected patient population.

Active auditory implants, such as the Maxum, provide significantly improved hearing function compared to hearing aids in patients with moderate to severe hearing loss who are not reaching their cochlear hearing potential. The speech perception gap (SPG), defined as PB Max (phonetically balanced maximum) minus word recognition score with hearing aid, is a useful measure of inadequate hearing aid performance. The Maxum middle ear implant provides significantly improved performance over hearing aids in patients with significant SPG because of superior high frequency gain. Patients with PB Max 60% or greater with SPG are possible candidates for the implant.

"Hearing loss in the pediatric population can have significant social and developmental implications. Early auditory rehabilitation by at least 6 months of age is imperative. Although traditional hearing aids are often a first-line treatment option, there is a wide array of implantable auditory devices available. This article describes the indications for such devices as they pertain to the pediatric population, including osseointegrated bone-conduction devices, middle ear implants, cochlear implants, and auditory brainstem implants."

Implantable auditory devices (IADs) are a viable hearing restoration option for patients with hearing loss. Conditions such as chronic otitis externa, congenital aural atresia, and chronic otitis media can be treated with a variety of implants. Progressive disease are also amenable to restoration with IADs, providing stabilized hearing. When considering the best rehabilitative options, the patient's preference, ease of surgery, ease of device use, quality of life, and the traditional alternatives (such as ossiculoplasty, hearing aids, and cochlear implants) need to be considered. Patients with conductive, mixed, and sensorineural losses, mild to severe in nature, can be candidates for IADs.

The Envoy Esteem and the Carina system are the 2 totally implantable hearing devices. The Esteem is designed for patients with bilateral moderate to severe sensorineural hearing loss who have an unaided speech discrimination score of greater than and equal to 40%. The Carina system is designed for patients with moderate to severe sensorineural hearing loss or those with mixed hearing loss. The Esteem offers a technologically advanced method to provide improvements in hearing and is available in the United States, whereas the Carina system is currently not available in the United States.

This article examines and evaluates methods, from an audiologist's perspective, of reducing common complaints with conventional hearing aids and issues such as the occlusion effect, acoustic feedback, discomfort, and insufficient gain. Although often successful, reducing one problem may have the tradeoff of causing another issue. This article is meant to provide information to the reader regarding modern conventional hearing aids, the means to alleviate common problems in the clinic, and when middle ear implants and osseointegrated implants can be beneficial.

The Vibrant Soundbridge is a semi-implantable, active middle ear implant that is a safe and effective treatment for patients with sensorineural hearing loss. Since Food and Drug Administration approval for this indication, many international investigators have expanded its use for conductive and mixed hearing losses. This article reviews the author's experience and the international uses of this versatile device.

Controversies have been associated with the etiology, diagnosis, evaluation, and management of otosclerosis since Valsalva first described stapes fixation as a cause of hearing loss. Although the exact mechanism of the bone remodeling associated with otosclerosis remains uncertain, stapedotomy has been accepted as the surgical treatment of most patients with stapedial otosclerosis. There remains a disparity of opinion, however, regarding the role of preoperative imaging, surgical technique, implant selection, and medical therapy for cochlear otosclerosis. In addition, opinions vary regarding the optimal postoperative care of patients undergoing stapedotomy and a patient's ability to participate in activities that may result in barotrauma.

Since the original carved Teflon stapes over vein graft, stapedectomy prostheses have undergone evolution. Prostheses shapes, materials, and surgical techniques for placement have reflected advances in biomaterials and surgical tools. The variability in prostheses has reflected alternative techniques of stapedectomy and stapedotomy and differing strategies for attachment to the incus. Although many iterations of stapes prostheses have been proposed, excellent results can be achieved with various prostheses designed to rest on tissue grafts in stapedectomy techniques or pass through the footplate in stapedotomy techniques when used by surgeons experienced with technique details specific to the selected prosthesis.

The use of imaging in otosclerosis for diagnosis, preoperative assessment, and follow-up has the potential to give the clinician an additional tier of patient evaluation and validation of diagnosis. Before stapes surgery, imaging may help avoid unnecessary middle ear explorations in nonotosclerotic cases, prevent potential complications, and assist in appropriate patient counseling regarding management expectations. Postoperatively, following unsuccessful air-bone gap closure in stapes surgery or conductive hearing deterioration following initial successful closure of the air bone gap, imaging can be used to determine the prosthesis position in the middle ear.

Surgical management of otosclerosis is a relatively safe and effective procedure, with a high rate of hearing improvement and a low rate of undesirable outcomes and complications. Many of these potential complications are common to any middle ear surgery, but many are unique to surgery involving the stapes footplate. Preventing complications with stapes surgery and minimizing their impact may be achieved by preparation as well as surgical experience.

The Vibrant Soundbridge is a means to rehabilitate patients with sensorineural hearing loss. It differs from hearing aids in that it uses mechanical energy rather than acoustic sound to deliver better sound quality to the inner ear. The implant's crucial component is a floating mass transducer that is directly fixed to the incus to drive it, which is introduced into the middle ear through a facial recess approach. Although this is a newer technology, studies thus far have demonstrated better hearing results compared with hearing aids in terms of functional gain and speech intelligibility, and better outcomes on subjective assessments.

Implantable hearing aids are gaining importance for the treatment of sensorineural hearing loss and also for mixed hearing loss. The various hearing aid systems, combined with different middle ear situations, give rise to a wide range of different reconstructions. This article attempts to summarize the current knowledge concerning the mechanical interaction between active middle ear implants (AMEIs) and the normal or reconstructed middle ear. Some basic characteristics of the different AMEIs are provided in conjunction with the middle ear mechanics. The interaction of AMEIs and middle ear and the influence of various boundary conditions are discussed in more detail.

Although ossiculoplasty, also known as ossicular chain reconstruction (OCR), was attempted initially in the early 1900s, it was not until the 1950s that it became commonplace and relatively well understood. Since then, there have been numerous technologic advances and a gain in the understanding of ossiculoplasty. However, successful OCR with resulting long-term stability can be a daunting task. Typically, the most common condition requiring revision OCR is chronic suppurative otitis media (COM) with or without cholesteatoma. Primary and revision OCR are performed also for blunt and penetrating trauma-induced conductive hearing loss, congenital defects (eg, atresia), and benign and malignant tumors. Typically, reconstruction in ears with COM is more difficult than in ears without infection. This article discusses the key factors involved in successful revision OCR.

This article describes outcomes for the Otologics active middle ear implant for the semi-implantable and fully implantable (Carina, Otologics LLC, Boulder, CO) devices. Inclusion and exclusion criteria are reported in detail for surgical and audiologic management. Results from the clinical trial demonstrated no change for unaided air and bone conduction thresholds and no significant change in monosyllabic word scores or sentences in noise. Experiments are reported for conductive and mixed types of hearing losses in animal and human cadaveric models. These devices are in their infancy, and further study is needed to better identify candidates and develop appropriate expectations.

For many hearing-impaired individuals, the benefits of conventional amplification may be limited by acoustic feedback, occlusion effect, and/or ear discomfort. The MAXUM system and other implantable hearing devices have been developed as an option for patients who derive inadequate assistance from traditional HAs, but who are not yet candidates for cochlear implants. The MAXUM system is based on the SOUNDTEC Direct System technology, which has been shown to provide improved functional gain as well as reduced feedback and occlusion effect compared to hearing aids. This and other implantable hearing devices may have increasing importance as future aural rehabilitation options.

The Vibrant Soundbridge is the world's most often implanted active middle ear implant or hearing aid. During the last few years, the device indications have expanded from sensorineural hearing loss to conductive and mixed hearing loss. Titanium couplers have led to improved contact of the floating mass transducer with the middle ear structures. The resulting hearing gain is satisfying for most patients, but so far, there is no clear audiologic advantage over conventional hearing aids. Currently, the indications are mainly related to intolerance of conventional hearing aids (eg, chronic otitis externa), severe mixed hearing loss with a destructed middle ear and certain medical diagnosis (eg, congenital atresia).

Active middle ear implants (AMEIs) are sophisticated technologies designed to overcome many of the shortcomings of conventional hearing aids, including feedback, distortion, and occlusion effect. Three AMEIs are currently approved by the US Food and Drug Administration for implantation in patients with sensorineural hearing loss. In this article, the history of AMEI technologies is reviewed, individual component development is outlined, past and current implant systems are described, and design and implementation successes and dead ends are highlighted. Past and ongoing challenges facing AMEI development are reviewed.

This article discusses the Envoy Esteem implantable hearing system, a completely implantable hearing device. The device is indicated for patients older than 18 years with stable moderate to severe sensorineural hearing loss and good speech discrimination. The device is placed through an intact canal wall tympanomastoidectomy with a wide facial recess approach. The implant is typically activated at 6 to 8 weeks postoperatively and usually requires several adjustments for optimal performance. The sound processor/battery lasts 4.5 to 9.0 years and can be replaced through a minor outpatient procedure.

Plasti-pore, a high-density polyethylene sponge, was one of the earliest biocompatible materials developed specifically for implantation in the middle ear. It is one of the most nonreactive materials known when tested in simulated biochemical exposure to pseudoextracellular fluid. The two basic prosthetic designs are the total ossicular replacement prosthesis and the partial ossicular replacement prosthesis. Plasti-pore implants have now been used for 20 years and are widely accepted by otologic surgeons. The basic properties of the material, implant design, and surgical techniques involved using these prostheses are reviewed in this article.

The footplate only situation remains the greatest challenge of ossicular reconstruction. This article discusses the long term results obtained with a new type of columella, the Spandrel, which combines the rigidity necessary for sound transmission with the flexibility required to comply with the dynamic movements of the neotympanum.

This article traces the evolution of transplant material in ossicular reconstruction of the middle ear. The first transplant consisted of the body and short process of the homograft incus. It was repositioned or wedged between the stapes head and the manubrium of the malleus. Further modification consisted of the sculpture of prostheses from homograft incudes; these were known as the notched incus with short or long process. By means of a notch in the short process, they were locked in place. The final phase is the use of hydroxyapatite as a biocompatible material from which similar prostheses may be precisely manufactured. These hydroxyapatite prostheses, known as the incus and incus-stapes replacement prosthesis, appear to be well tolerated and to produce excellent hearing results.

The use of self-stabilizing, presculpted cartilage homografts for middle ear reconstruction has an established track record with long-term results equivalent to reconstruction methods using alloplastic material. This method affords several advantages over other techniques, which will be discussed in detail.

Although successful stapedectomy is very gratifying for both the patient and surgeon, complications can arise, often with disastrous results. Certain clues may alert the surgeon to risk prevention or possible complications, allowing early definitive management. This assumes critical importance today as fewer younger surgeons acquire extensive experience in stapedectomy. A thorough knowledge of possible problems and their management is mandatory for the otologist who undertakes this most challenging of operations.

The greatest chance of success in stapedectomy is at the time of the initial procedure. Complications are compounded and successes markedly decreased when revision surgery is attempted. The most common pitfalls encountered in stapedectomy are reviewed in this article. Principles of surgery that have minimized complications and decreased the need for revision procedures in the authors' practices are outlined. Guidelines helpful when considering revision surgery also are presented and specific indications are addressed.

The middle ear works as a highly sensitive pressure receptor. Sound pressure waves induce a vibration of its structures with amplitudes of molecular dimensions.’ This mechanical function indicates that these delicate structures are also moved by the variations of ambient air pressure, with its million-times higher pressures and amplitudes, as they occur during swallowing, blowing one’s nose, with gusts of wind, with every opening of the eustachian tube, during diving, flying, and so forth. Experiments in temporal bones concerning middle ear mechanics demonstrated that an intricate micromechanism has developed to cope with the incredibly small acoustic vibrations and with the relatively huge displacements caused by static pressure variations. The key element of this micromechanic construction is the ossicular chain with its three ossicles and their delicate joints.21 If a reconstruction technique in the middle ear, for example the implantation of a passive prosthesis, interferes with this micromechanism, the insertion must be compatible with these mechanics of the ossicular chain for optimal efficiency. This premise also applies to the insertion of the active vibrator of an implantable hearing aid. Most designs attach the transducer to the ossicular chain and thus must comply with both the acoustic and the atmospheric changes of pressure in the middle ear. Experience with the mechanics of passive ossicular replacement prostheses used for reconstructive proceduresz6 can be valuable for the integration of the transducer. Therefore, this article focuses first on the description of the loads, pressures, and movements which characterize the mechanics of the normal middle ear. This description is followed by a discussion of some micromechnical aspects of the middle ear prostheses and of transducers of implantable hearing aids.

The Vibrant Soundbridge, a semi-implantable hearing device for subjects with moderate to severe sensorineural hearing impairment was introduced commercially. First audiologic results are presented on 63 patients from 10 European implant centers. Hearing loss was at 0.5, 1, 2, and 4 kHz varying between 43 and 81 dB HL. The patients used the analogue audio processor, type 302. Measured sound-field gain was compared with NAL-R target values. For most patients an acceptable agreement was found. There was a subgroup of patients, however, with relatively low gain. The results suggest that this was related to the suboptimal positioning and fixation of the transducer to the incus.

Plasti-pore, a high-density polyethylene sponge, was one of the earliest biocompatible materials developed specifically for implantation in the middle ear. It is one of the most nonreactive materials known when tested in simulated biochemical exposure to pseudoextracellular fluid. The two basic prosthetic designs are the total ossicular replacement prosthesis and the partial ossicular replacement prosthesis. Plasti-pore implants have now been used for 20 years and are widely accepted by otologic surgeons. The basic properties of the material, implant design, and surgical techniques involved using these prostheses are reviewed in this article.

From 1956 to the present has been a period of surgical expansion into the middle ear for correction of deafness. This article follows the evolution of microscopic implants designed to replace all or part of the ossicular chain, and the use of biocompatible materials of plastic, metal, and ceramics to form prosthetic devices.

The Lippy-modified Robinson prosthesis has been used for years in revision stapedectomy and has proved successful in reconstructing the absent lenticular process. When this technique fails, an ossicle cup prosthesis can be used. The ossicle cup and columella have been used for 20 years with continuing success. The advantages of the semibiologic prostheses are as follows: The prosthesis can be sized as each case requires, giving a variable height above the remaining stapes. The prosthesis is designed not to touch the promontory or facial nerve canal. The synthetic portion of the semibiologic prosthesis does not touch the tympanic membrane. An efficient perpendicular action is achieved from the tympanic membrane to the stapes footplate. The prosthesis remains in place during tympanic membrane movement. A stable dynamic joint is provided with the stapes capitulum (ossicle cup). A safe platform is provided that distributes the weight of the assembly prosthesis over the entire stapes footplate (ossicle columella). Although both semibiologic prostheses are used routinely for partial and total ossicular replacement, other troublesome and technically difficult ossicular reconstruction problems can also be solved by the adaptability of the synthetic portion of the prosthesis. Because the synthetic portion of the prosthesis can be modified by notching, shaping, and trimming, the following problems can be overcome: A laterally healed tympanic membrane can be reached by increasing the length of the synthetic shaft. In the absence of the stapes capitulum, the cup is notched in two places (180 degrees apart) to fit the shoulders of the remaining stapes. Remaining crura on the footplate can be bypassed by trimming the synthetic footplate to fit in between the crura. The stapes with a low profile can be utilized by increasing the length of the synthetic shaft. An abnormal stapedial tendon attachment to the stapes capitulum can be overcome with a single notch in the cup. An overhanging facial nerve can usually be bypassed by the narrow design of the ossicle columella. The future of ossiculoplasty will rest more on the solution of ancillary problems than on ossiculoplasty techniques. These troublesome ancillary problems include eustachian tube dysfunction, cholesteatoma control, mucosa regeneration, and fibrosis during the healing process. The self-correcting process of ossiculoplasty is an evolutionary process, and the small surgical steps taken are slowly incorporated into surgical principles. Incorporating a synthetic prosthesis within a natural or synthetic ossicle is a logical and evolutionary step in the science of ossicular reconstruction.

The use of self-stabilizing, presculpted cartilage homografts for middle ear reconstruction has an established track record with long-term results equivalent to reconstruction methods using alloplastic material. This method affords several advantages over other techniques, which will be discussed in detail.

This article discusses the role of the new Ionomeric middle ear prostheses for ossicular chain reconstruction. Although the prostheses are composed of a rigid alloplastic material, they can be easily sculpted to conform to the middle ear anatomy.

Measurement of the acoustic properties of middle ear prostheses in an appropriate model prior to insertion in humans should be part of the routine of the prosthesis development and testing process, but it is not. This article describes a human temporal bone model suitable for such testing and discusses the results of several commonly used prostheses evaluated in the model. By comparing existing and new experimental prostheses in such a model, we should be better able to develop prostheses capable of providing improved hearing results following middle ear reconstruction.

We have presented an extensive review of congenital ossicular anomalies. These deformities occur in combination with one another or as isolated problems with equal frequency. They are so rare that even the busiest otologists have limited clinical experience with them. The astute otologist will keep these facts in mind when assessing congenital middle ear problems in the office and in the operating room. Careful, detailed history taking may reveal the presence of familial conductive hearing loss or other congenital syndromes. Complete head and neck examination as well as observation of the extremities may provide clues to the otologic diagnosis. Microscopic examination of the ear reveals abnormalities of the tympanic membrane, malleus, and incus. Audiometric and radiologic evaluation augments physical examination. At surgery, the otologist must be prepared to perform a variety of possible surgical procedures, from traditional ossiculoplasty and stapedectomy to fenestration. Hearing aids are an option for patients with congenital ossicular anomalies, and the possibility of inoperability must be kept in mind; the patient must be prepared for this eventuality. Congenital ossicular anomalies present a challenge to the otologic surgeon, and their successful treatment, the greatest reward.