Original contributionBone conduction variation poststapedotomy
Introduction
Otosclerosis is a hereditary disease affecting the osseous tissue of the labyrinthic capsule. Disordered neoformation of osteoid material compromises the functionality of the ossicular chain (particularly the stapediovestibular joint) and of the sensorineural apparatus of the inner ear, determining stapes fixity with reduction of auditory capacity [1].
Liminal tonal audiometry shows, in the initial phase of the pathology, an exclusively transmissive hearing loss that becomes mixed and then purely sensorineural for a progressive bone conduction decay [2].
Anatomopathologic and epidemiologic studies reveal the presence of otosclerosis in 10% of the population [3], although it becomes clinically evident in only 1% as a consequence of stapes fixity. Women are more frequently affected by this pathology than men in, at a 2:1 ratio [4].
Otosclerosis is a hereditary autosomal dominant disease with incomplete penetrance.
So far, 3 gene loci have been identified [5]: OTSC 1,OTSC 2, and OTSC 3.
However, other researchers [6] suggest the possible presence of a fourth, as yet unidentified, locus.
Sensorineural hearing loss in the otosclerotic patient has been attributed over the years to different causes. Some authors believe it is caused by the presence of toxic substances in the labyrinthine fluids causing irreversible damage to the inner ear structures, in particular the hydrolytic enzymatic component [7]. Other authors contend it is a consequence of the effects of cochlear fluid hypertension affecting the organ of Corti [8].
The treatment of otosclerosis is exclusively surgical.
Stapes surgery gained its actual definition in the 1950s with the stapedectomy operation proposed by Rosen [9] in 1953 and the stapedotomy operation introduced by Shea [10] in 1958. Adequate bone conduction is a fundamental prerequisite for a successful outcome of a subsequent operation for otosclerotic disease. Surgery may be inadvisable in cases in which there is a preexisting bone conduction deficit [2]. It is therefore extremely useful to monitor the variation in bone conduction immediately postoperatively, and several years later to compare the results with the patient's opposite, nonoperated, otosclerotic ear.
The aim of the present study was to evaluate the variation in bone conduction auditory thresholds in patients undergoing surgical intervention for otosclerosis, comparing the operated ear with the also-affected-by-otosclerotic-disease, nonoperated, contralateral ear, in relation to the surgical techniques applied.
Section snippets
Materials and methods
One hundred ten patients who underwent initial surgery for otosclerotic disease between 1998 and 2001 were studied. Surgery was always performed on the ear with the poorer air conduction threshold in the frequencies considered (0.5, 1, 2, and 3 kHz). Different surgical techniques were used: in 45 subjects, a microdriller was used and in 65 subjects carbon dioxide laser (Table 1). To avoid the influence of presbyacusia, patients older than 55 years were excluded from the study.
All surgical
Results
Preoperative audiometric data are presented in Table 2.
During audiometric postoperative follow-up, performed at a minimum of 3 years after the operation, we observed the following (Fig. 1):
- (a)
In 45 patients who underwent traditional surgery (group A): in 43 subjects (95.6%), a reduction of the transmissive gap; in 2 subjects (4.4%), a sensorineural hearing loss, concerning frequencies of 500, 1000, 2000, and 3000 Hz. Furthermore, in 43 cases in which bone conduction did not decrease, we found a
Discussion
Analysis of functional results shows that most study patients achieved considerable auditory gain after surgical operation.
The closure of the cochlear reserve within 10 dB, in both subjects groups, overlapped without any significant statistical difference. Similarly, no statistically significant difference was observed between the 2 groups in relation to the incidence of sensorineural postoperative hearing loss. Irrespective of the surgical technique adopted, our data show the risk of
Conclusions
This audiologic study on patients who underwent operation reveals that bone conduction hearing loss indicated by tonal audiometry may be overestimated in relation to the difficulties found in evaluating true bone conduction vs artifact. In fact, bone conductibility may improve in otosclerotic patients after the surgical operation. This result allows us to express a positive prognosis concerning surgical outcome when considering otosclerotic patients with sensorineural hearing loss and small
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Audiologic comparison of classification systems of advanced otosclerosis
2022, American Journal of Otolaryngology - Head and Neck Medicine and SurgeryCitation Excerpt :Given the significant improvement in our patients after stapedotomy and the small number of patients requiring evaluation for further hearing rehabilitation, we agree that the majority of advanced otosclerosis patients should undergo stapedotomy given the potential benefit. Stapedotomy has been shown to improve bone conduction thresholds, which may explain why many patients with far advanced otosclerosis improve to a degree that they no longer qualify for cochlear implantation [14]. While there was an improvement in the mean bone conduction thresholds for all the groups, only the PTA and BC groups had statistically significant improvements.
Stability of computed tomography densitometry in patients with otosclerosis:a two-year follow-up
2022, Journal of OtologyCitation Excerpt :Otosclerosis causes conductive hearing loss due to a fixation of the stapes (CHOLE and MCKENNA, 2001) and accounts for up to 85% of the conductive hearing loss in the Caucasian population (Stewart, 2001). Stapedectomy and stapedotomy are the only treatments that have proven effective in reversing the symptoms of otosclerosis (Moscillo et al., 2006). These surgeries are often required in both ears since bilateral otosclerosis accounts for up to 87.5% of otosclerosis patients (Xie et al., 2019).
Study of the improvement in bone conduction threshold after stapedectomy
2016, Acta Otorrinolaringologica EspanolaLaser versus non-laser stapedotomy in otosclerosis: A systematic review and meta-analysis
2014, Auris Nasus LarynxCitation Excerpt :The argon laser was the first laser system to be clinically used for stapedotomy and was reported to have good results by Palva [5] in 1978. From then on, all different types of laser systems, such as KTP, argon, erbium, YAG and CO2 lasers, were assessed for their suitability for stapes footplate perforation [6–11]. But none of them were believed to have any overwhelming advantage over the others in audiological results post-operatively [12–14], although the main advantages of the laser included the high precision of its application, the high ablation efficiency, and the low risk of floating footplate due to the noncontact manipulation of these systems [6].
Bilateral hearing results of 751 unilateral stapedotomies evaluated with the Glasgow benefit plot
2010, Journal of Laryngology and OtologyHearing results of 1145 stapedotomies evaluated with Amsterdam hearing evaluation plots
2009, Journal of Laryngology and Otology