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Ossicular Chain (ossicular + chain)
Selected AbstractsSecretory meningioma of the middle ear: A light microscopic, immunohistochemical and ultrastructural study of one caseNEUROPATHOLOGY, Issue 1 2008Giovanna Cenacchi A 66-year-old woman was referred with left hearing loss. A probable diagnosis of left secretory otitis media with effusion was formulated. A left myringotomy was performed to remove hyperplastic hard tissue from the tympanic cavity. A high resolution CT scan of the temporal bone disclosed a soft-tissue mass completely involving the mastoid and tympanic cavity, surrounding the ossicular chain which appeared spared with no signs of infiltration. The histopathologic, immunohistochemical and ultrastructural response was secretory meningioma, a rare variant of conventional meningothelial meningioma in atypical sites. [source] Necrosis of the long process of the incus following stapes surgery: New anatomical observations,,THE LARYNGOSCOPE, Issue 4 2009Imre Gerlinger MD Abstract Objectives/Hypothesis: The most frequent complication (generally recognized during revision procedures) following seemingly successful stapedotomies and stapedectomies is necrosis of the long process of the incus. This is currently ascribed to a malcrimped stapes prosthesis or to a compromised blood supply of the incus. The two-point fixation can cause a mucosal injury with a resulting toxic reaction, and also osteoclastic activity. An important aspect in the engineering of ideal stapes prostheses is that they should be fixed circularly to the long process of the incus with appropriate strength. The objective of this study was to compare current knowledge relating to the blood supply of the ossicular chain with the present authors' observations on cadaver incudes. Most of the papers dealing with this issue appeared in the mid-20th century. Methods: The published data were compared with the authors' findings gained from photodocumentation on 100 cadaver incudes. The photos were taken with a Canon EOS 20 digital camera (Canon, Inc., Lake Success, NY) with a 5:1 macro-objective. The long processes of the incudes were examined from four directions under a Leica surface-analyzing microscope (Leica Microsystems GmbH, Wetzlar, Germany). Results: Analysis of the positions of the entrances of the feeding arteries (nutritive foramina) on the incudes revealed 1-4 nutritive foramina on the long processes of 48% (24) of the left-sided incudes and 56% (28) of the right-sided incudes. The positions of these foramina differed, however, from those previously described in the literature. They were mostly located not on the medial side of the incus body or on the short process or on the cranial third of the long processes, but antero-medially, mostly on the middle or cranial third. In 48% of all the incudes examined, an obvious foramen was not observed either in the body or in the long process of the incus. No relationship was discerned between the chronological age of the incus specimens and the numbers and/or locations of the nutritive foramina. In each case, the opening of the foramen was the beginning of a tunnel running obliquely and medially upward through the corticalis of the long process of the incus. The foramina are thought to be capable of ensuring a richer blood supply between the surface and the inside of the long process, allowing the arteries to run in and out. Conclusions: These observations indicate that conclusions drawn from classical anatomical works appear to need reconsideration. The present authors consider that the reason for the necrosis of the long process of the incus is not a compromised blood supply, except in some exceptional anatomical situations. They discuss the possible reasons why malcrimping may lead to necrosis of the long process of the incus. To prevent such malcrimping, attention is paid to the new generation of prostheses. Laryngoscope, 2009 [source] Cartilage tympanoplasty: Indications, techniques, and outcomes in A 1,000-patient seriesTHE LARYNGOSCOPE, Issue 11 2003John Dornhoffer MD Abstract Objectives/Hypothesis: The purpose of this study was to analyze the anatomical and audiologic results in more than 1,000 cartilage tympanoplasties that utilized a logical application of several techniques for the management of the difficult ear (cholesteatoma, recurrent perforation, atelectasis). Our hypothesis was that pathology and status of the ossicular chain should dictate the technique used to achieve optimal outcome. Study Design: Retrospective clinical study of patients undergoing cartilage tympanoplasty between July 1994 and July 2001. A computerized otologic database and patient charts were used to obtain the necessary data. Methods: A modification of the perichondrium/cartilage island flap was utilized for tympanic membrane reconstruction in cases of the atelectatic ear, for high-risk perforation in the presence of an intact ossicular chain, and in association with ossiculoplasty when the malleus was absent. A modification of the palisade technique was utilized for TM reconstruction in cases of cholesteatoma and in association with ossiculoplasty when the malleus was present. Hearing results were reported using a four-frequency (500, 1,000, 2,000, 3,000 Hz) pure-tone average air-bone gap (PTA-ABG). The Student t test was used for statistical comparison. Postoperative complications were recorded. Results: During the study period, cartilage was used for TM reconstruction in more than 1,000 patients, of which 712 had sufficient data available for inclusion. Of these, 636 were available for outcomes analysis. In 220 cholesteatoma cases, the average pre- and postoperative PTA-ABGs were 26.5 ± 12.6 dB and 14.6 ± 8.8 dB, respectively (P < .05). Recurrence was seen in 8 cases (3.6%), conductive HL requiring revision in 4 (1.8%), perforation in 3 (1.4%), and postand intraoperative tube insertion in 11 (5.0%) and 18 ears (8.2%), respectively. In 215 cases of high-risk perforation, the average pre- and postoperative PTA-ABGs were 21.7 ± 13.5 dB and 11.9 ± 9.3 dB, respectively (P < .05). Complications included recurrent perforation in 9 ears (4.2%), conductive HL requiring revision in 4 (1.9%), postoperative and intraoperative tube insertion in 4 (1.9%) and 6 ears (2.8%), respectively. In 98 cases of atelectasis, the average pre- and postoperative PTA-ABGs were 20.2 ± 10.9 dB and 14.2 ± 10.2 dB, respectively (P < .05). Complications included 1 perforation (1.0%), conductive loss requiring revision in 2 cases (2.0%), and post- and intraoperative tube insertion in 7 (7.1%) and 12 ears (12%), respectively. In 103 cases to improve hearing (audiologic), the average pre- and postoperative PTA-ABGs were 33.6 ± 9.6 dB and 14.6 ± 10.1 dB, respectively (P < .05). Complications included 1 perforation (1.0%), conductive loss requiring revision in 11 (11%), and post- and intraoperative tube insertion in 6 (5.8%) and 2 (1.9%), respectively. Conclusions: Cartilage tympanoplasty achieves good anatomical and audiologic results when pathology and status of the ossicular chain dictate the technique utilized. Significant hearing improvement was realized in each pathological group. In the atelectatic ear, cartilage allowed us to reconstruct the TM with good anatomic results compared to traditional reconstructions, which have shown high rates of retraction and failure. In cholesteatoma, cartilage tympanoplasty using the palisade technique resulted in precise reconstruction of the TM and helped reduce recurrence. In cases of high-risk perforation, reconstruction with cartilage yielded anatomical and functional results that compared favorably to primary tympanoplasty using traditional techniques. We believe the indications for cartilage tympanoplasty (atelectatic ear, cholesteatoma, high-risk perforation) were validated by these results. [source] Lateralization During the Weber Test: Animal ExperimentsTHE LARYNGOSCOPE, Issue 3 2002Jean-Yves Sichel MD Abstract Objectives/Hypothesis The objective of this study were to present an assessment of a new theory to explain lateralization during the Weber test using an animal model. This theory is based on the discovery that a major pathway in bone conduction stimulation to the inner ear is through the skull contents (probably the cerebrospinal fluid [CSF]). The placement of a bone vibrator or tuning fork on the skull excites the inner ear by the classic osseous pathway and by the suggested CSF pathway. We assume that there is a phase difference between the stimulation mediated by the ossicular chain (inertial and occlusion mechanisms) and the one mediated by the CSF. The presence of a conductive pathology will decrease the magnitude of the sound energy mediated by the ossicular chain. Thus, the out-of-phase signal arriving through the bony pathways will be decreased, hence increasing the resultant sound intensity stimulating the cochlea. Study Design Prospective animal study. Methods The experiment was performed on 10 fat sand rats, which had undergone unilateral cochleostomy and a small craniotomy. The auditory nerve brainstem response (ABR) thresholds were measured to air-conducted stimulation, to stimulation with the bone vibrator applied to the skull, and to stimulation with the bone vibrator applied directly to the brain through the craniotomy. The ossicular chain of the second ear was then fixed to the middle ear walls with cyanoacrylate glue to induce a conductive hearing loss. The ABR thresholds to the same three stimuli were then measured again. Results After ossicular chain fixation, the ABR threshold to air-conducted stimulation increased, to bone vibrator stimulation on the bone decreased (hearing improvement), and to bone vibrator stimulation directly on the brain remained unchanged. Conclusions This experiment confirms the proposed theory. During clinical bone conduction stimulation, there is a phase difference between sound energy reaching the inner ear through the middle ear ossicles and from the CSF. A middle ear conductive pathology removes one of these components, thus increasing the effective sound intensity in the affected ear. On the other hand, when the bone vibrator is applied on the brain, the inner ear is stimulated only through the CSF, so ossicular chain fixation does not change the ABR threshold. Moreover, this study proves that lateralization during the Weber phenomenon is the result, at least in part, of an intensity difference between sound energy reaching the two cochleae. [source] Hearing Results After Primary Cartilage Tympanoplasty,THE LARYNGOSCOPE, Issue 12 2000Matthew J. Gerber MD Abstract Objectives/Hypothesis Cartilage,perichondrium grafting of the tympanic membrane has been used in an effort to reduce recurrence or progression of middle ear disease. The rigidity of cartilage has obvious benefit in preventing tympanic membrane retraction, but concern has been raised regarding its sound conduction properties. Few studies in the literature address hearing results after cartilage tympanoplasty. The purpose of this study was to investigate the hearing results after primary cartilage tympanoplasty and compare them with results after primary tympanoplasty with temporalis fascia. Study Design A retrospective review of all ear surgeries using cartilage between 1994 and 1999 was performed. Methods Only primary cases in which the ossicular chain was intact and no mastoid surgery was performed were included. Indications for surgery included tympanic membrane perforation, retraction, and cholesteatoma. Pre- and postoperative speech reception thresholds and air,bone gaps at 500 Hz, 1000 Hz, 2000 Hz, and 4000 Hz were compared. Results Eleven patients comprised the cartilage study group, and there were 11 age- and temporally matched control subjects. The mean improvement in speech reception threshold for both the study group and the control group was 10 dB. The majority of patients in both groups had ABG closure to within 10 dB at all frequencies examined. There were no statistically significant differences in speech reception threshold improvement or air,bone gap closures between the two groups. Conclusions These results demonstrate that hearing results after cartilage tympanoplasty are comparable to those after temporalis fascia tympanoplasty. Therefore, when indicated, a cartilage,perichondrium graft can be used for prevention of disease recurrence or progression without fear of impairing hearing. [source] Audiometric evaluation of an attempt to optimize the fixation of the transducer of a middle-ear implant to the ossicular chain with bone cementCLINICAL OTOLARYNGOLOGY, Issue 1 2004A. Snik Audiometric evaluation of an attempt to optimize the fixation of the transducer of a middle-ear implant to the ossicular chain with bone cement Typically, an implantable hearing device consists of a transducer that is coupled to the ossicular chain and electronics. The coupling is of major importance. The Vibrant Soundbridge (VSB) is such an implantable device; normally, the VSB transducer is fixed to the ossicular chain by means of a special clip that is crimped around the long process of the incus. In addition to crimping, bone cement was used to optimize the fixation in six patients. Long-term results were compared to those of five controls with crimp fixation alone. To assess the effect of bone cement (SerenoCem®, Corinthian Medical Ltd, Nottingham, UK) on hearing thresholds, long-term post-surgery thresholds were compared to pre-surgery thresholds. Bone cement did not have any negative effect. Next, to test the hypothesis that aided thresholds might be better with the use of bone cement, aided thresholds were studied. After correction for the severity of hearing loss, only a small difference was found between the two groups at one frequency, viz. 2 kHz. It was concluded that there was no negative effect of using bone cement; however, there is also no reason to use bone cement in VSB users on a regular basis. [source] | ||||||||||