Cochlear otosclerosis: statistical analysis of relationship of spiral ligament hyalinization to hearing loss

Cochlear implantation outcomes in advanced otosclerosis

INTRODUCTION

Several studies support the use of cochlear implants (CI) in far-advanced otosclerosis (FAO).

MATERIAL AND METHODS

We compared our results of CI in patients with FAO and unknown origin hearing loss (UOHL) and our incidence of facial electrical stimulation and difficult insertion of the electrode bundle up to 3 to 5 years from surgery.

RESULTS

We found 17 patients with CI in FAO and UOHL. FAO patients achieved better results on the pure tone average (PTA) and recognition of monosyllables by GEE test (p=0.022; p=0.006), and particularly at 1 year on the PTA (p=0.002), at 6 months and a year in monosyllables (p=0.002; p=0.001), and at 6 months in disyllables (p=0.004). There were no differences toward complications.

CONCLUSION

In our experience, placement of CI in FAO has proven successful, with results comparable to other similar cohorts, and with low complications.

Cochlear implantation outcomes in patients with far advanced otosclerosis

OBJECTIVES

To compare hearing outcomes in patients with far advanced otosclerosis (FAO) undergoing cochlear implantation to an age-matched group of controls, to describe the effects of cochlear ossification on hearing, and to review the adverse effects of implantation in patients with FAO.

HYPOTHESIS

Hearing performance in patients with FAO after cochlear implantation is comparable to similarly treated postlingually deafened adults without FAO. Ossification or retrofenestral otosclerosis does not predict poor hearing outcomes. Modiolar-hugging technology reduces postoperative facial nerve stimulation.

STUDY DESIGN

Retrospective chart review.

SETTING

Academic neurotologic tertiary referral center.

PATIENTS

Thirty patients with FAO, who metaudiological criteria for cochlear implantation, were compared to 30 age-matched controls, postlingually deafened by non-otosclerotic causes.

MAIN OUTCOME MEASURES

Audiometric pre- and postoperative speech reception threshold, word, and sentence scores were analyzed. The presence of retrofenestral findings on computed tomography or intraoperative cochlear ossification were noted.

RESULTS

In the FAO group, radiographic abnormalities were noted in 26.4% of patients. Intraoperative ossification requiring drillout was seen in 29.4% of patients. None developed postoperative facial nerve stimulation. There was no difference between the FAO and control groups in the mean short-term and long-term postoperative speech reception threshold, word, and sentence scores (P = .77). The presence of radiographic abnormalities did not predict hearing outcome. Intraoperative cochlear ossification was not associated with worse short-term word and sentence scores (P = .58 and 0.79, respectively), and for the long-term hearing outcome (P = .24).

CONCLUSIONS

In patients with FAO, effective and safe hearing rehabilitation can be accomplished with cochlear implantation.

Prediction of Stapes Footplate Thickness Based on the Level of Hearing Loss in Otosclerosis

During surgical treatment of a patient with otosclerosis, the probability of success depends in large part on the extent of the surgeon's experience. Therefore, predicting the preoperative severity of disease may help determine the choice of surgeon based on how experienced the surgeon should be. We conducted a study to evaluate the relationship between hearing thresholds and footplate thickness in otosclerosis patients who underwent stapes surgery. We used a qualitative method for measuring footplate thickness that was based on the simplicity or difficulty of opening the footplate. Our study population was divided into two groups; group 1 was made up of 66 patients whose footplates were easily opened with low pressure or with repeated motions by hand, and group 2 was made up of 14 patients whose footplate was either opened by drilling or not opened because it had been obliterated. We found that the patients in group 2, who had more severe disease, had significantly higher air-and bone-conduction thresholds than did the patients in group 1. According to our findings, otosclerotic patients with high air- and bone-conduction thresholds generally have more severe disease and thus require a more experienced surgeon.

Cochlear Implantation of Patients with Far-Advanced Otosclerosis

OBJECTIVE

This current single-subject, repeated-measures study was to describe our experience with 30 patients who had been diagnosed with "far-advanced otosclerosis" and who were included in our program of cochlear implants. We analyzed the history of the patients and their families before implantation, the surgical findings, and the performance over a follow up of 3 years.

MATERIAL AND METHODS

All patients met one or more of the after criteria: 1) previous surgical intervention as a treatment of their otosclerosis; 2) signs of pericochlear hypodensities in high resolution computed tomography (HRCT) scans; and 3) family precedents of otosclerosis. All underwent standard surgical cochlear implantation.

RESULTS

In 78% of the cases, a stapedectomy had previously been realized. Cochlear otosclerosis could be appreciated in HRCT in 78% of the patients. A family history of otosclerosis was found in 40%, and 33.3% of patients had familial precedents of nonfilial hypoacusis. The mean results in the two-syllable test were 20% preimplantation, 54% 6 months after implantation, and 52%, 62%, 54% at 1, 2, and 3 years after implantation. In the CID sentence test, they were in the order of 32% preimplantation and of 64% at 6 months, 66% after 1 year, of 68% after 2 years, and reaching 72% after 3 years. No complications related to the surgery were detected.

CONCLUSION

Patients diagnosed with far-advanced otosclerosis have a good prognosis with cochlear implantation comparable to that of other patients in whom postlingual implants are performed.

Questioning the Relationship between Cochlear Otosclerosis and Sensorineural Hearing Loss: A Quantitative Evaluation of Cochlear Structures in Cases of Otosclerosis and Review of the Literature

BACKGROUND

The literature provides conflicting information regarding the prevalence and cause of sensorineural hearing loss (HL) in individuals with otosclerosis.

OBJECTIVE

The purpose of this study was to further evaluate the association between involvement of the cochlear endosteal layer with otosclerosis and sensorineural HL.

STUDY DESIGN

Retrospective case review.

METHODS

Temporal bones and audiograms from five individuals with otosclerosis were evaluated. The cochlear elements were quantified. The location and extent of the cochlear element loss was correlated with the location and extent of endosteal involvement with otosclerosis.

RESULTS

A reduction in the population of cochlear elements was observed in most individuals; however, the reduction was not proportional to the extent of endosteal involvement with otosclerosis. The cochlear elements remained normal adjacent to some areas of endosteal involvement with otosclerosis. One individual with extensive cochlear otosclerosis had normal hearing and predominantly normal cochlear elements.

CONCLUSION

This study demonstrates a variable amount of degeneration of the cochlear elements in individuals with otosclerotic involvement of the endosteum. The reduction in the population of cochlear elements was not related to the extent and location of endosteal involvement with otosclerosis. These findings suggest that factors that limit the effect of otosclerotic endosteal involvement on the cochlear elements or processes that effect the cochlear elements directly and are independent of bone involvement may be present.

Pathophysiology of otosclerosis

OBJECTIVE

To review current knowledge of the pathophysiology of otosclerosis and to review hypotheses for the amelioration of this disease.

DATA SOURCES

Review of the literature and experimental observations by the authors.

CONCLUSIONS

Otosclerosis is a localized disease of bone remodeling within the otic capsule of the human temporal bone. Unlike other similar bone diseases, it does not occur outside of the temporal bone. These lesions seem to begin by resorption of stable otic capsule bone in adults, followed by a reparative phase with bone deposition. There are clearly genetic factors that lead to this disease, but measles virus infection and autoimmunity also may play contributing roles. Surgical correction of the conductive hearing loss is highly effective, but nonsurgical intervention has not yet been shown to prevent or slow the disease. Of the factors that may inhibit this process, fluorides, cytokine inhibitors, and bisphosphonates, third-generation bisphosphonates appear to hold the most promise.

Cochlear otosclerosis 30 years after stapedectomy confirmed by CT, MRI

A 64-year-old Japanese male patient, status post-stapedectomy, presented with progressive, bilateral SNHL of 30 years' duration. CT showed extensive demineralization of the otic capsule, suggestive of otospongiotic change in both ears. There were no hyperostotic lesions found, which would have been suggestive of otosclerotic change. MRI showed a morphologically intact membranous labyrinth in both ears, with no obstruction of the cochlear lumen. It was concluded that the patient has progressive otospongiotic change of the otic capsule, but no otosclerotic change.

High-resolution computed tomographic evaluation of the cochlear capsule in otosclerosis: relationship between densitometry and sensorineural hearing loss

Otosclerotic cochlear involvement is a rather frequent disease that has not been clearly understood in terms of diagnosis and management. Objective evaluation methods are needed to confirm the clinical diagnosis, investigate the relationship with hearing impairment, and validate the results of treatment. In this study two ear groups with bone conduction hearing loss (BCHL) were investigated with audiometry and high-resolution computed tomography (HRCT). In the first group (n = 22) the diagnosis of fenestral otosclerosis was confirmed at operation; the second group (n = 9) was composed of ears clinically suspicious for purely cochlear involvement. Additionally, a control group (n = 14) of otologically normal ears was also studied. Foci of demineralization were demonstrated in 58% of the ears in the two groups; the sensorineural hearing loss (SNHL) in those ears was significantly worse than in those with normal radiologic findings. Three methods of HRCT densitometry were used to determine the abnormal regions in the cochlear capsule; the results suggested that hypodense regions were consistent with a greater degree of SNHL, in contrast to the hyperdense ones in ears with better cochlear reserves. Agreement was found between the location of the density change and the frequency topography of the SNHL; densitometric values were correlated with the bone conduction thresholds for certain frequencies. It is concluded that the spongiotic foci are responsible for the SNHL, since there was a correlation between their location and the SNHL frequency. The determination of better hearing in those ears with sclerotic foci supports the hypothesis that the sclerotic phase may not be a healing process following the spongiotic phase, and that it can be the first stage of the disease.