Outcome analysis of cochlear implant reimplantation in children.

OBJECTIVES: We review our experience gained in performing cochlear reimplantation in 25 children who have had multichannel cochlear implant device failure at the Cochlear Implant Center of the Manhattan Eye, Ear and Throat Hospital and Lenox Hill Hospital (New York, NY), to assess the feasibility of cochlear reimplantation in children and the effect of reinsertion on audiological performance. STUDY DESIGN: We retrospectively analyzed the outcome of 27 consecutive multichannel cochlear implant reinsertions performed in 25 children at the Manhattan Eye, Ear and Throat Hospital and Lenox Hill Hospital. These reimplantations were performed between 1990 and 1999, with a minimum follow-up of 6 months for both surgical and audiological performance. METHODS: Charts were reviewed for patient factors, findings at the time of initial operation and repeat operation, and results of audiological testing both before and after reimplantation. RESULTS: Surgical complications of reimplantation included two intraoperative cerebral spinal fluid leaks and two late postoperative flap breakdowns with implant extrusions. For the most part, depth of electrode insertion was unchanged. Open-set speech recognition scores and speech perception abilities remained stable or improved compared with results before reimplantation. CONCLUSION: Our results confirm that cochlear implant reimplantation is technically feasible and allows for continued auditory development for the child who has a cochlear implant device failure.

Preventing labyrinthitis ossificans: the role of steroids.

OBJECTIVE: To identify a possible relationship between the administration of steroids at the time of diagnosis of bacterial meningitis and the development of labyrinthitis ossificans. DESIGN: Retrospective analysis of the charts of 38 children requiring cochlear implantation who presented with bacterial meningitis and then developed bilateral profound deafness. The patients' charts were reviewed for age at diagnosis, the type of antibiotic administered, and the administration, dosage, and duration of steroid (dexamethasone) therapy. Labyrinthitis ossificans was established by preoperative computed tomographic and/or magnetic resonance imaging and by the intraoperative findings as described in the operative report. PATIENTS AND METHODS: Patients were 38 children who received cochlear implantation by a single senior otolaryngologist for bacterial meningitis-related deafness. Ten patients' charts (26%) were available for full review; 9 of these 10 patients had documented pneumococcal meningitis and the other patient had Haemophilus influenzae-type meningitis. RESULTS: One of the 6 patients who received steroid therapy at the time of initial illness had documented evidence of labyrinthitis ossificans either radiographically or at the time of surgery. All 4 patients who failed to receive steroid therapy developed labyrinthitis ossificans. The results achieve statistical significance by chi2 analysis and a t test (P<.01). CONCLUSION: The results of this retrospective study are highly suggestive of a role for steroids in preventing the development of labyrinthitis ossificans in children with pneumococcal meningitis.

Canalplasty.

An essential requisite for successful ear surgery is a patent external ear. A number of anatomic variants or abnormalities may obstruct its lumen, resulting in conductive hearing loss, hampering access for routine ear cleansing, or obscuring underlying pathology. This article reviews a surgical technique for canalplasty that can be modified to successfully treat either bone or soft tissue blockages of the external auditory canal.

Cochlear implantation in children with enlarged vestibular aqueducts.

OBJECTIVES: This report details our experience with cochlear implantation in children with both profound sensorineural HL (SNHL) and enlarged vestibular aqueducts (EVAs). It seeks to determine if the abnormal anatomy of EVA predisposes to any adverse events during or after cochlear implantation. STUDY DESIGN: A retrospective review. METHODS: Charts were reviewed for details of the procedure, complications, and audiologic outcome. RESULTS: Between 8/25/93 and 9/16/98, 10 children with EVAs received cochlear implants, of whom 8 children (5 males, 3 females; mean age 7.8 y) had audiologic follow-up of at least 6 months. The implant was inserted without difficulty in all patients. Pulsatile clear fluid via the cochleostomy was observed in five patients, but was easily controlled in each instance. There have been no major complications, although two patient had short-lived postoperative vestibular symptoms and one child has experienced an intermittent pulsing sensation in her head. Speech perception measures were obtained using a battery of tests that assessed the children's ability to perceive speech in both open- and closed-set formats. Two patients were excluded because the implant was placed within the last 6 months. Of the remaining eight children identified with EVAs, seven (86%) demonstrated open-set word recognition. CONCLUSIONS: These favorable results may be attributed in part to HL that occurs relatively late in childhood, allowing implantation in postlingual candidates. Cochlear implantation can be safely and effectively performed in children with SNHL associated with EVAs.

Specific language growth in young children using the CLARION cochlear implant.

General and specific language growth was evaluated in 10 children who had received the CLARION Multi-Strategy Cochlear Implant during the clinical trial. The mean age at implantation was 37 months, and the children were followed for 18 months thereafter. Language comprehension and use were assessed with the Peabody Picture Vocabulary Test, the Reynell Developmental Language Scales, and mean length of utterance (MLU). The mean vocabulary scores indicated a 42-month increase in 18 months. The mean language comprehension increased from 20.4 to 40.8 months, and language use increased from 21.5 to 38.1 months. The mean MLU increased from 1.8 words to 4.8 words during the test period. Results indicated the children learned language at the same rate as their hearing peers of the same language age (except for vocabulary, which was faster), but retained a language delay relative to their hearing peers of the same chronological age.

Increased numbers of mast cells in human middle ear cholesteatomas: implications for treatment.

HYPOTHESIS: Because many of the biologic phenomena in which mast cells are involved also are observed in human cholesteatoma pathology, the authors hypothesized that mast cells may play a role in this disease. The first test of this hypothesis is to determine whether there are an increased number of mast cells associated with cholesteatomas. BACKGROUND: The molecular and cellular defects that result in the pathologic features observed in acquired and congenital cholesteatomas are unknown. One common feature of cholesteatoma pathogenesis is the presence of bacteria and a numerous inflammatory cytokines expressed by host inflammatory cells. The interactions between inflammatory cells and cholesteatoma epithelium could result in the induction of other aberrant biologic features of cholesteatomas. Thus, it is critical to the understanding of the pathogenesis of cholesteatomas to define the specific role of each cell type involved in this disease. Connective tissue mast cells have a complex retinue of functions mediated via the secretion of a variety of cytokines and proteinases, and many of the biologic phenomena in which mast cells are involved also are observed in cholesteatoma pathology. METHODS: The authors evaluated by immunohistochemistry 36 cholesteatomas of all types (e.g., primary and secondary acquired, recurrent, and congenital) and 23 specimens of normal tissues (e.g., tympanic membrane, canal wall skin, and postauricular skin) for the expression of tryptase, a mast cell-specific protease. RESULTS: Cholesteatomas showed approximately threefold to sevenfold increase in the concentration of mast cells when compared with that of normal tissues. In addition, 19-34% of the mast cells were found within the suprabasal layers of the squamous epithelium of cholesteatoma subgroups, a phenomenon observed only in grossly inflamed tympanic membrane specimens, but not in other control tissues including minimally inflamed tympanic membranes. CONCLUSIONS: The authors conclude from these data that mast cells may represent a previously unrecognized host inflammatory cell, which plays an important role in the development of one or more traits of cholesteatoma pathology.

Cholesteatoma: a molecular and cellular puzzle.

HYPOTHESIS: There are at least three possible molecular models of cholesteatoma pathogenesis. Cholesteatoma may arise as a result of 1) the induction of a preneoplastic or neoplastic transformation event; 2) a defective wound-healing process; and/or 3) a pathologic collision of the host inflammatory response, normal middle ear epithelium, and a bacterial infection. BACKGROUND: There have been a number of speculations concerning the factors that foster the development of cholesteatoma. Before resolving the molecular basis for the pathogenesis of cholesteatomas, it is important to present and test plausible models that could explain how a cholesteatoma becomes invasive, migratory, hyperproliferative, aggressive, and recidivistic. METHODS: The authors evaluated by various techniques (e.g., immunohistochemistry, flow cytometry, and image analysis) a large number of cholesteatomas of all types (e.g., primary and secondary acquired, recurrent, and congenital) and a range of normal tissues (tympanic membrane, canal wall skin, and postauricular skin) for the expression of various proteins (e.g., p53, ectopeptidases, tryptase) and for the presence of DNA aneuploidy. RESULTS AND CONCLUSIONS: The authors' published and unpublished studies to date support several suppositions concerning the pathology of cholesteatomas. First, cholesteatoma epithelium behaves more like a wound-healing process than a neoplasm. The available evidence to date does not indicate that cholesteatomas have inherent genetic instability, a critical feature of all malignant lesions. Second, the induction of hyperproliferative cells in all layers of the cholesteatoma epidermis implicates a potential idiopathic response to both internal events as well as external stimuli in the form of cytokines released by infiltrating inflammatory cells. Third, the presence of bacteria may provide a critical link between the cholesteatoma and the host, which prevents the cholesteatoma epithelium from terminating specific differentiation programs and returning to a quiescent state in which it becomes minimally proliferative, nonmigratory, and noninvasive. Fourth, none of our data suggest that there are any obvious molecular or cellular differences among the various types of cholesteatomas (e.g., primary and secondary acquired, recidivistic, and congenital). Continued research should delineate the precise molecular and cellular dysfunction involved in the pathogenesis of cholesteatomas and how this knowledge can be useful in the clinical management of cholesteatomas.

Is chronic otitis media with cholesteatoma associated with neurosensory hearing loss?

OBJECTIVE: This study aimed to determine whether chronic otitis media (COM) with cholesteatoma over time is associated with a decrease in neurosensory function. STUDY DESIGN: This study was a review of a database of all patients with cholesteatoma treated surgically. SETTING: The study was conducted at a tertiary care medical center and specialty hospital. PATIENTS: There were children and adults with unilateral COM with acquired, nontraumatic cholesteatoma in this study. INTERVENTIONS: All patients received preoperative pure-tone bone conduction and speech audiometry. MAIN OUTCOME MEASURES: Interaural difference between the cholesteatomatous and normal ears comparing bone conduction pure-tone average (BC-PTA), pure-tone threshold at 4,000 Hz (BC4000), and/or speech discrimination score (SDS) as measured by a repeated measures analysis of covariance, with age as a covariate was examined. RESULTS: A significant difference between ears for SDS and BC4000 that does not vary with age was identified. A significant interaural difference for the BC-PTA that varies with patient age was identified. CONCLUSIONS: Chronic otitis media with cholesteatoma is associated with a decrease in neurosensory function, even in the absence of frank inner ear invasion.

Expression of p53 protein in human middle ear cholesteatomas: pathogenetic implications.

BACKGROUND: Cholesteatoma is a destructive lesion of the middle ear or mastoid process or both. The molecular and cellular defects that result in the clinical hallmarks of acquired and congenital cholesteatomas, namely invasion, migration, uncoordinated proliferation, altered differentiation, aggressiveness, and recidivism, are unknown. Determining the existence of defects in the normal biology, biochemistry, and genetic complement of the major cellular constituents comprising a cholesteatoma (i.e., fibroblasts and keratinocytes) is critical to the understanding of the pathogenesis of cholesteatomas. It has been speculated that the development of human cholesteatomas is due, in part, to the altered control of cellular proliferation, which tilts the balance toward the aggressive, invasive growth of squamous epithelium within the middle ear. However, whether this altered control is due to defects in the mechanisms and underlying genes that control proliferation, or to cytokines released from infiltrating inflammatory cells, or to some other mechanism is unknown. The nuclear phosphoprotein p53 tumor suppressor gene plays a critical regulatory role in cell cycle control and apoptosis. In the current article, the authors have analyzed congenital, primary and secondary acquired, and recurrent cholesteatomas for the altered expression of p53 and Ki-67, a marker of active proliferation. METHODS: p53 and Ki-67 expression was determined by immunohistochemical assays using specific monoclonal antibodies. RESULTS: The authors' results indicate that p53 is elevated 9- to 20-fold in all cholesteatomas when compared to the expression of p53 in normal postauricular skin or tympanic membrane. However, there is no concomitant increase in Ki-67 expression in cholesteatomas. CONCLUSIONS: These data indicate a defect in cholesteatomas in the mechanisms that p53 engages (i.e., cell cycle control or apoptosis or both). In addition, these data further suggest that there is no intrinsic difference between any clinicopathologic group of cholesteatomas, at least with respect to p53-expression and, presumably, p53 function.

Auditory perceptual abilities in a child with a nucleus and a Clarion cochlear implant.

This case study will review the performance of a 7-year-old female who was implanted at the age of 3 years 9 months with a Nucleus 22 channel device. This child was deafened from pneumococcal meningis at the age of 8 months and was placed in an early intervention program which uses simultaneous communication (i.e. speech with sign language). The teaching staff of this particular educational setting has collaborated closely with the Cochlear Implant Center at Manhattan Eye, Ear and Throat Hospital and the team's teacher of the deaf. The child utilized the implant on a daily basis for a period of 2 years 10 months. Performance on a variety of auditory perceptual tests were obtained at 1 year and two year intervals. After almost 3 years of implant use, the child suffered an internal receiver failure. The Nucleus device was explanted and the child was implanted with a Clarion Cochlear Implant System. Performance on a similar set of auditory perceptual tests obtained after 3 and 6 months use indicated better performance with the Clarion device. In addition to the scores on the individual tests, a comparison questionnaire was used to obtain impressions from the parents and the school personnel. Results should be reviewed with caution since this study investigates the responses of a single child who uses each of these two different implants and cannot be generalized.

Surgical techniques for cochlear implantation in the very young child.

Early cochlear implantation to treat prelingually deafened children has been shown to improve speech perception and overall performance. The current age limit for implantation is 24 months in accordance with US Food and Drug Administration guidelines, but it is believed that earlier implantation is possible and may result in better performance. Implantation in children younger than 36 months, however, is complicated by the altered anatomy of the temporal bone in this young age group. We have developed specific modifications in the cochlear implantation technique for this young age group. This technique was used in implantation for 17 children younger than 36 months. The ages ranged from 16 to 36 months and averaged 30 months. All patients except one had complete electrode insertion without complication. The technique of cochlear implantation must be modified not only for differences in anatomy in these young children but also for the expected continued growth of the temporal bone and related structures. Cochlear implantation can be safely performed on children as young as 16 months.

DNA analysis of human cholesteatomas.

HYPOTHESIS: The hypothesis tested in this article is that if cholesteatomas are a low-grade squamous cell neoplasm, then evidence of genetic instability, in the form of abnormal or aneuploid amounts of DNA, should be evident. BACKGROUND: Cholesteatoma is a destructive lesion of the middle ear and/or mastoid process that produces complications by erosion of the temporal bone. The clinical hallmarks of cholesteatomas, namely invasion, migration, uncoordinated proliferation, altered differentiation, aggressiveness, and recidivism, are traits typically associated with the neoplastic cell. However, there is little evidence to support or refute the speculation that cholesteatomas are a low-grade squamous cell neoplasm. the existence of defects in the genetic complement of the major cellular constituents comprising a cholesteatoma, fibroblasts and keratinocytes, would support the speculation that cholesteatomas are a neoplasm, since cancers commonly manifest quantitative and qualitative alterations in the normal euploid complement of genetic information, resulting in a cell that has an abnormal or aneuploid amount of DNA. METHODS: DNA content (ploidy) within cholesteatoma tissues was measured by flow cytometry and image analysis. RESULTS: The DNA content of 11 human cholesteatomas and nine postauricular skin specimens was analyzed using flow cytometry, while the DNA content of 10 cholesteatoma specimens was analyzed using image analysis. Interpretable data was obtained from 10 cholesteatoma specimens and six postauricular skin specimens. One cholesteatoma specimen demonstrated an abnormal aneuploid DNA content, whereas the remaining nine cholesteatomas and the six postauricular skin specimens demonstrated a normal euploid DNA content. CONCLUSIONS: We conclude that, due to the lack of overt genetic instability, as evidenced by the presence of a normal euploid DNA content, cholesteatomas are not low-grade neoplasms.

Altered regulation of cell surface peptidases in human cholesteatoma.

Cholesteatoma is a destructive process involving an accumulation of desquamated keratin arising from squamous epithelium that pathologically has invaded the middle ear or mastoid process. The clinical hallmarks of cholesteatomas, namely invasion of healthy tissues, migration, unrestrained proliferation, aggressiveness, recidivism, and uncoordinated differentiation predict the existence of defects in the normal biology and biochemistry of the cellular constituents that compose a cholesteatoma, as well as in the cellular interactions between these cells, the surrounding normal tissue, and the host. In the current report, we analyzed 11 cholesteatomas and matched healthy tissue for altered expression in four different cell surface peptidases, aminopeptidase A, aminopeptidase N, dipeptidyl peptidase IV, and neutral endopeptidase. We suggest that peptidases may modulate cell growth and differentiation by inactivating stimulatory signals (or conversely, by activating inhibitory signals).

Canalplasty.

Canal stenosis and atresia can result from a number of causes, including congenital, inflammatory, neoplastic and iatrogenic pathologic conditions. Canalplasty is an eclectic collection of techniques designed to recreate a patent and trouble-free external canal. Despite the large number of etiologies, the principles of canalplasty are the same. The goal is the creation of a widely patent and physiologically intact canal wall. Both the bony and cartilaginous portions must be addressed surgically. Care should be taken to preserve the normal skin and adnexa for lining the canal, but if this is not adequate, skin grafts should be used to prevent healing by secondary intent. Overcorrection of stenosis is advised. We have presented our basic technique for canalplasty and discussed its alteration for specific disorders.

Cochlear implant mechanical failures.

Cochlear implants have proven to be an effective treatment for profoundly deafened individuals. Unfortunately, like most mechanical devices, these implants occasionally cease to function. The rate at which the cochlear implant fails, however, does not appear to be the same in adults and children. The failure rate for children far exceeds that observed in adults. The overall failure rate reported by Cochlear Corporation notes that whereas only 3% of the adults have had this type of problem, 9% of the children have had failed internal receivers. This research reports on the experiences of a large implant facility in the Northeast. The clinical presentation and the evaluation of children suspected of having an implant failure are reviewed. The mechanical causes for failures are analyzed. Intraoperative findings and results of reimplantation surgery are presented. The possible causes for the increased incidence of failure in children are discussed.

Pediatric cholesteatoma: an individualized, single-stage approach.

We report our experience with a one-stage surgery for pediatric cholesteatoma in 216 ears. Our technique is based on three main principles: (1) the surgery is individualized; (2) the goal of surgery is to completely remove cholesteatoma and related disease in one operation; and (3) the reconstruction is performed to provide both good hearing and a dry, trouble-free ear. The incidence of recidivism was 10.2%, and the rate achieved was 13.3% at 5 years and 24% at 10 years. Canal wall down surgery was the predominant procedure used. The incidence of intraoperative neurosensory hearing loss, vertigo, and facial nerve injury was extremely low. The postoperative cavity problems encountered were minimal.

Beta-2 transferrin: limitations of use as a clinical marker for perilymph.

Beta-2 transferrin is a protein marker that can be used in the clinical setting to reliably identify the presence of cerebrospinal fluid (CSF). Recent literature has suggested that beta-2 transferrin can also be used as a clinical marker for perilymph. This study investigates the use of a beta-2 transferrin assay as a method to identify the presence of perilymph. Twenty-two patients were enrolled in the study. Fluid samples were obtained intraoperatively and tested for the presence of beta-2 transferrin. As expected, four CSF samples collected were positive for beta-2 transferrin; however, four known perilymph samples collected from patients undergoing cochlear implantation were negative for beta-2 transferrin, seven of nine known perilymph samples obtained during stapedectomies were negative for beta-2 transferrin, and four of five samples collected during middle ear explorations for fistula were negative for beta-2 transferrin. With current methodology beta-2 transferrin does not appear to be a reliable clinical marker for perilymph in the operative setting.