Isabelle Schrauwen, Guy Van Camp
The etiology of otosclerosis: a combination of genes and environment.
Laryngoscope. 2010 Jun;120(6):1195-202. doi: 10.1002/lary.20934.
Abstract/Text
Otosclerosis is a common form of hearing loss characterized by abnormal bone remodeling in the otic capsule. It is a complex genetic disease, caused by a combination of genetic and environmental factors. During the past decade, several attempts have been made to identify factors for otosclerosis. This review provides an overview of the current understanding of the etiology of otosclerosis and describes the genetic and environmental factors that have been implicated in the disease. Environmental factors include fluoride and viral factors, particularly measles. Genetic association studies for otosclerosis have reported several associations of genetic variants that influence the risk of disease, mainly involving bone remodeling pathways, although their individual risk contributions are small. Rare monogenic forms of otosclerosis also exist, which are caused by a mutation in a single gene leading to a clear familial segregation of the disease. Linkage analysis of large otosclerosis families has led to the identification of seven loci, and recently evidence was found that T cell receptor beta is a gene responsible for familial otosclerosis, suggesting an underlying immunological pathway. However, this might also represent an autoimmune process, a hypothesis that is supported by other data as well. In conclusion, a variety of pathways have been identified to be involved in the development of otosclerosis, showing that distinct mechanisms involving both genetic and environmental risk factors can influence and contribute to a similar disease outcome.
F A Thiers, G E Valvassori, J B Nadol
Pathology case of the month: otosclerosis of the cochlear capsule: correlation of computerized tomography and histopathology.
Am J Otol. 1999 Jan;20(1):93-5.
Abstract/Text
Kensuke Kiyomizu, Tetsuya Tono, Dewen Yang, Atsushi Haruta, Takao Kodama, Shizuo Komune
Correlation of CT analysis and audiometry in Japanese otosclerosis.
Auris Nasus Larynx. 2004 Jun;31(2):125-9. doi: 10.1016/j.anl.2004.01.006.
Abstract/Text
OBJECTIVE: To determine the extent of audiometric correlation with CT findings.
METHODS: Forty-four patients (82 ears) with surgically confirmed otosclerosis underwent preoperative CT examination. Based on the computed tomography (CT) findings, the ears were classified into five groups as follows: Group A, the group with no pathological CT findings; Group B1, the group with demineralization localized in the region of the fissula antefenestram; Group B2, the group with demineralization extending towards the cochleariform process from the anterior region of the oval window; Group B3, the group with extensive demineralization surrounding the cochlea; and Group C, the group with thick anterior and posterior calcified plaques.
RESULTS: There were 32 ears (39.0%) in Group A, 21 ears (25.6%) in Group B1, 16 ears (19.5%) in Group B2, 7 ears (8.5%) in Group B3, and 6 ears (7.3%) in Group C. The mean bone conduction levels were greater in the order of the extent of demineralization: Groups A, B1-B3 suggesting positive relationship between the cochlear function and the degree of labyrhinthine otosclerosis.
CONCLUSION: A good correlation between the preoperative CT findings and audiometry findings suggests that CT with a slice intervals between 0.5 and 1mm could provide useful informations in assuming the extent of otosclerosis in the inner ear.
R J Wiet, S A Morgenstein, T A Zwolan, S M Pircon
Far-advanced otosclerosis. Cochlear implantation vs stapedectomy.
Arch Otolaryngol Head Neck Surg. 1987 Mar;113(3):299-302.
Abstract/Text
In 1981, our group, as part of a Food and Drug Administration investigator team directed by William House, performed Illinois' first cochlear implantation. We have since performed cochlear implantations in ten other persons. Since May 1980, approximately 35 severely to profoundly deaf persons per year have been referred to our clinic for evaluation. A small number of these patients had far-advanced otosclerosis. In these cases, exploratory tympanotomy and stapedectomy followed by rehabilitation with a hearing aid was a more appropriate management than cochlear implantation. Case histories and a temporal bone study of far-advanced otosclerosis are presented.
Liselotte J C Rotteveel, David W Proops, Richard T Ramsden, Shakeel R Saeed, Adriaan F van Olphen, Emmanuel A M Mylanus
Cochlear implantation in 53 patients with otosclerosis: demographics, computed tomographic scanning, surgery, and complications.
Otol Neurotol. 2004 Nov;25(6):943-52.
Abstract/Text
OBJECTIVES: To collect data from a large number of cochlear implant recipients with otosclerosis and to make an assessment of these patients' clinical characteristics, computed tomographic scans, surgical findings, and complications, and to quantify the occurrence of postoperative facial nerve stimulation.
STUDY DESIGN: Retrospective multicenter study.
PATIENTS: Fifty-three patients with otosclerosis from four cochlear implant centers in the United Kingdom and The Netherlands were reviewed. Sixty surgical procedures were performed in these patients: 57 devices were placed in 56 ears.
RESULTS: The computed tomographic imaging demonstrated retrofenestral (cochlear) otosclerotic lesions in the majority of patients. Although not statistically significant, the extent of otosclerotic lesions on the computed tomographic scan as categorized in three types tends to be greater in patients with rapidly progressive hearing loss, in patients in whom there is surgically problematic insertion of the electrode array, and in patients with facial nerve stimulation. In four patients, revision surgery had to be performed. Twenty of 53 (38%) patients experienced facial nerve stimulation at various periods postoperatively.
CONCLUSION: Cochlear implant surgery in patients with otosclerosis can be challenging, with a relatively high number of partial insertions and misplacements of the electrode array demanding revision surgery. A very high proportion of patients experienced facial nerve stimulation mainly caused by the distal electrodes. This must be discussed with patients preoperatively.
Paul Merkus, Maarten C van Loon, Conrad F Smit, Cas Smits, Adrianus F C de Cock, Erik F Hensen
Decision making in advanced otosclerosis: an evidence-based strategy.
Laryngoscope. 2011 Sep;121(9):1935-41. doi: 10.1002/lary.21904. Epub 2011 Aug 16.
Abstract/Text
OBJECTIVES/HYPOTHESIS: To propose an evidence-based strategy for the management of patients with advanced otosclerosis accompanied by severe to profound hearing loss.
STUDY DESIGN: Systematic review of the literature and development of treatment guidelines.
METHODS: A systematic review was conducted on (advanced) otosclerosis and cochlear implantation or stapedotomy. We focused on hearing results, radiological findings, and surgical complications. Based on the results of the literature review and our own experience, we suggest a strategy to make decisions for the treatment of patients with advanced otosclerosis.
RESULTS: In cases of severe mixed hearing loss due to advanced otosclerosis, hearing aids may not result in optimal hearing rehabilitation, and cochlear implantation can be considered. However, there could be specific surgical dilemmas concerning cochlear implantation in advanced otosclerosis due to otospongiotic foci around, and otosclerotic foci within, the cochlea. Decision making in these patients can be difficult, especially because a stapedotomy may still be an effective treatment next to hearing aids. An algorithm is presented, based on the speech discrimination score, computed tomography classification and the air-bone gap, which will guide the surgeon to either cochlear implantation, stapedotomy, or a hearing aid and follow-up.
CONCLUSIONS: To achieve optimal hearing with minimal disadvantages in patients with otosclerosis and severe to profound hearing loss, an algorithm can help in the selection of patients for either cochlear implantation, stapedotomy, or hearing aids and follow-up.
Copyright © 2011 The American Laryngological, Rhinological, and Otological Society, Inc.
A S Cruise, A Singh, R E Quiney
Sodium fluoride in otosclerosis treatment: review.
J Laryngol Otol. 2010 Jun;124(6):583-6. doi: 10.1017/S0022215110000241. Epub 2010 Feb 18.
Abstract/Text
OBJECTIVES: To review the current literature on the use of sodium fluoride in the treatment of otosclerosis.
DESIGN: A literature review was conducted, searching the Medline and PubMed database from 1966 to 2009, using the terms 'otosclerosis' and 'fluoride'. Article abstracts were reviewed and relevant full articles acquired.
RESULTS: There has been only one double-blind, placebo-controlled trial of the use of sodium fluoride in otosclerosis patients, and this found a reduced incidence of deterioration in hearing after two years in the treatment group. Several case-control series have described a hearing benefit in the sodium fluoride treated group. Treatment doses vary greatly, and there is no evidence regarding the optimum duration of treatment.
CONCLUSIONS: There is low quality evidence suggesting that sodium fluoride may be of benefit to preserve hearing and reduce vestibular symptoms in patients with otosclerosis.
Tino Just, Ellen Guder, Hans Wilhelm Pau
Effect of the stapedotomy technique on early post-operative hearing results--Preliminary results.
Auris Nasus Larynx. 2012 Aug;39(4):383-6. doi: 10.1016/j.anl.2011.07.009. Epub 2011 Aug 20.
Abstract/Text
OBJECTIVE: To compare three stapedotomy modalities used to fenestrate the stapes footplate in patients with primary otosclerosis.
MATERIALS: The non-randomized and unblinded one-center study included 48 patients with primary otosclerosis who underwent stapes surgery between May 2008 and April 2009. The patients were divided into three groups (single shot and two-shot CO(2) laser stapedotomy, perforator) depending on the modality used for stapedotomy. Bone conduction (BC) and air conduction (AC) thresholds, air-bone gap (ABG), and the difference between mean pre-operative and 2- to 3-week post-operative BC thresholds were analyzed.
RESULTS: The temporary BC deterioration was most pronounced at 6 and 8kHz after 2-shot laser stapedotomy. A significant drop in AC or BC was not found in any of our 48 patients. Age, high-dose cortisone therapy, and 'preoperative hearing' did not influence the post-operative hearing results.
CONCLUSION: Even though the number of patients presented here was small and statistical analysis was limited, the study showed a trend toward worse BC thresholds at 6 and 8kHz after a second shot CO(2) application. Whenever possible, treatment should avoid a second laser shot on the already opened inner ear with the laser parameters used for the initial shot.
Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.
