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PubMed2006

Tympanosclerosis involving the ossicular chain: mobility of the stapes in association with hearing results.

CONCLUSION: The preoperative bone conduction level provides not only prognostic information but also information on the mobility of the stapes in tympanosclerosis. The surgical results depend upon the stapes mobility. OBJECTIVES: We aimed to evaluate operative findings and hearing results of tympanosclerosis involving the ossicular chain, in order to understand the pathophysiology and to establish better surgical treatment of tympanosclerosis. PATIENTS AND METHODS: Between January 1998 and March 2004, 29 patients (29 ears) with tympanosclerosis involving the ossicular chain underwent tympanoplasty at our hospital. Patients with myringosclerosis only, or with an associated cholesteatoma, were excluded from this study. The clinical and operational records and pre- and postoperative pure tone audiograms were reviewed retrospectively. RESULTS: Intact canal wall tympanoplasty was applied to all 29 patients. A non-staged operation was performed on 21 patients, and a staged operation was performed on the remaining 8 patients. In 25 patients (86.2%), the sclerotic lesion of the ossicles was located in the epitympanum. In the remaining four, the sclerotic lamella coated only the ossicular chain. On average, the preoperative air conduction hearing level of 57.9 dB was significantly improved to 46.3 dB after tympanoplasty. The success rate of middle ear surgery was 65.5% (19 of 29 patients), according to the criteria of the Otological Society of Japan. In 16 patients (55.2%), the mobility of the stapes was preserved (group A), while in the remaining 13 patients (44.8%), the stapes was fixed (group B). The mean preoperative bone conduction of 25.5 dB in group A was significantly better than that of 37.2 dB in group B. The hearing result significantly improved in group A but not in group B. The success rates were 75% (12 of 16 patients) in group A and 53.8% (7 of 13 patients) in group B.

Adolescent↗
PubMed1997

[An implantable hearing aid for inner ear hearing loss. Short-term implantation of microphone and transducer].

A microphone constructed for implantation in the posterior wall of the auditory canal and a piezoelectric transducer serving as the main components of an implantable hearing aid were temporally implanted in five patients during middle ear surgery under local anesthesia. The microphone was positioned beneath the skin of the auditory canal such that it completely covered the microphone membrane. The vibratory element of the transducer was coupled to the malleus in four patients with normal ossicular chains and directly to the stapes in one patient with missing incus. The microphone and transducer were electrically connected with an external battery-driven signal amplifier. Speech material and music were presented in the operation room at a sound level of 65 dB SPL under free-field conditions. The patients had to estimate the quality of speech, music, and their own voice as well as the effects of bone-conducting noises. All patients were able to hear with the system. An intraoperative talk without vision contact was possible without any problems, as was understanding of numerals ("Freiburger Zahlentest"). Perception of music was judged as "clear and undistorted with all broadband component." The estimation was also valid for one patient with a sensorineural hearing loss. One patient declared the music to be "a little of unnatural." Bone-conducted sound was estimated as normal in two patients, better than without an implant in one patient with sensorineural hearing loss, and "somewhat metallic" in another patient. Hearing the own voice was considered "normal" in two cases "monotonous" in one case, and "a little bit roaring" in another case. An amplification factor that can be technically realized in an implantable hearing aid was necessary for one of the patients with sensorineural hearing loss to perceive music at a pleasant volume. On the basis of this study, essential requirements for the construction of a fully implantable hearing aid are fulfilled.

Adult↗
PubMed1996

Ototoxicity of aminoglycoside drugs in tuberculosis treatment.

The possible ototoxic effect of kanamycin, streptomycin and a standard anti-TB drug combination, used in the treatment of 92 TB patients (7-71 years old), was examined by measuring the highest audible electric bone conduction frequency before and after treatment, using an Audimax 500 audiometer. At the so-called "safe" levels of drug administration it was found that kanamycin was markedly ototoxic, streptomycin very slightly ototoxic and the standard anti-TB drug combination had practically no ototoxic effect. Furthermore, it was found that none of these drugs were gender specific. Lastly, the possible effects of ageing on highest audible bone conduction frequency is discussed.

Adolescent↗
PubMed2004

Long-term follow-up of tinnitus in patients with otosclerosis after stapes surgery.

We prospectively studied 48 otosclerosis patients over a 2-year interval. Forty-four had stapedotomy, and four had stapedectomy. Demographics, clinical history, and pre- and postoperative audiometry results were recorded. A questionnaire asking about tinnitus (intensity, pitch) and including a visual analog scale quantifying the degree (1-10) of annoyance caused by the tinnitus was completed pre- and postoperatively (4-10 months and 14-48 months, respectively). Ninety-one percent of the otosclerosis patients reported the presence of tinnitus, and 39.58% reported severe disabling tinnitus (SDT; 7-10 on the visual analog scale). High-pitch (whistle) tinnitus was present in most patients, and white noise (radio static, waterfall, rain) was present in others. No patient described the tinnitus as a low-tone noise (buzzing). Ninety-one percent of patients reported tinnitus reduction or total remission after surgery. Ten of 19 patients with SDT reported complete remission of tinnitus, 7 reported improvement postoperatively, and 2 reported no change. No patient reported worsening of tinnitus. Small postoperative air-bone gaps (four tonal average) correlated with remission or reduction of tinnitus in SDT patients. Tinnitus pitch, gender, and age of patients were not related to decrease of tinnitus postoperatively. A larger preoperative air-bone gap correlated with larger reduction of tinnitus after successful surgery. A lower preoperative bone conduction level correlated with more intense tinnitus before surgery and greater reduction postoperatively. We contacted 25 patients from 14 to 48 months after surgery, and all reported that their tinnitus status had not changed since the early follow-up. Tinnitus is very prevalent in otosclerosis patients; almost one-half of patients have SDT preoperatively, and stapes surgery improves this symptom in 91% of cases. Preoperative air-bone gap and bone conduction level and a postoperative airbone gap seem to influence the degree of postoperative tinnitus reduction.

Adolescent↗
PubMed2005

[Clinical classification and relationship with conductive deafness of congenital middle ear malformations].

OBJECTIVE: To investigate the clinical classification and relationship with conductive deafness of congenital middle ear malformations. METHODS: From 1995 to 2004, 64 patients (82 ears) with single congenital middle ear malformations were operated in the ENT department of the General Hospital of Chinese People's Liberation Army. According to the histology and embryology of middle ear and the findings of surgical exploration, the clinical classification was performed. Statistical analysis was used to judge the differences of hearing loss in different type of congenital middle ear malformations. RESULTS: According to the embryologic development of the structures in middle ear, congenital middle ear malformations were classified 4 types. Type A: congenital ossicular chain anomalies; type B: congenital fusion of stapes; type C: congenital hypoplasia or atresia of oval/round widows. Hearing loss of three types on language frequency have no obvious difference (P = 0.1617), but there were statistical difference on high frequency ( > 2 kHz) between type A with type B and type C (P <0.05). Furthermore, descension of bone conduction and mixed deafness were familiar in type B and C. CONCLUSIONS: According to embryologic development, it was rational that congenital middle ear malformations were classed 3 types mentioned above. Hearing loss due to middle ear malformations could be distinguished by descension of bone conduction and air conduction on high frequency ( >2 kHz).

Adolescent↗
PubMed2004

Functional morphology of the middle ear in Chlorotalpa golden moles (Mammalia, Chrysochloridae): predictions from three models.

The ossicular apparatus of golden moles in the genus Chlorotalpa has received comparatively little attention in the literature, although the malleus is known to be intermediate in size between the "unmodified" malleus of Amblysomus and the hypertrophied mallei found in some other golden moles. In the present study, the middle ear structures of three Chlorotalpa species (C. duthieae, C. sclateri, and C. arendsi) are described. Measurements of middle ear structures were applied into three existing models of middle ear function. The predictions from the models suggest that the airborne hearing of Chlorotalpa species is limited to relatively low frequencies, but the impedance transformation by the middle ear apparatus is expected to be reasonably efficient. The sensitivity of the middle ear apparatus to inertial bone conduction is intermediate between that predicted for Amblysomus and that predicted for species with hypertrophied mallei. Hearing in fossorial mammals may be limited by factors other than the middle ear apparatus: the predictions for Chlorotalpa must therefore be treated with caution. However, a consideration of the "intermediate" middle ear morphology of Chlorotalpa species sheds some light on the origin of ossicular hypertrophy in golden moles. The limited enlargement of the malleus seen in Chlorotalpa is expected to have improved seismic sensitivity by bone conduction significantly at low frequencies, while airborne hearing might not have been adversely affected.

Animals↗
PubMed2004

Spiral ligament and stria vascularis changes in cochlear otosclerosis: effect on hearing level.

OBJECTIVE: To investigate the effect of changes within the spiral ligament and stria vascularis on hearing in cochlear otosclerosis, we examined spiral ligament hyalinization, stria vascularis atrophy, and sensory hearing loss in cochlear otosclerosis and described changes in ion transport molecule expression. STUDY DESIGN: Retrospective. SETTING: Tertiary referral center. PATIENTS: Thirty-two cochleae from 24 temporal bone donors with histologic evidence of cochlear otosclerosis, including spiral ligament hyalinization. INTERVENTION: Audiography. MAIN OUTCOME MEASURES: Measurements of spiral ligament width, stria vascularis, and bone-conduction thresholds were compared by the amount of hyalinization. Expression of the ion transport molecules Na,K-ATPase, connexin 26, and carbonic anhydrase II were assessed by immunohistochemical techniques. RESULTS: Hyalinization most often involved the posterior basal turn (88%) and the posterior middle turn (27%). Spiral ligament hyalinization correlated significantly with stria vascularis atrophy in the posterior middle turn of the cochlea (rho = -0.63, p < 0.01). There was a trend toward a significant association in the posterior basal turn (rho = -0.31, p < 0.08). Bone-conduction thresholds at 2,000 and 4,000 Hz were significantly associated with the amount of stria vascularis atrophy (rho = -0.44, -0.40, p < 0.05). In addition, we observed decreased immunostaining for both carbonic anhydrase II with Type I fibrocytes and Na,K-ATPase with stria vascularis and Type II and Type IV fibrocytes of the spiral ligament in cochlear otosclerosis sections compared with normal cochlea. Na,K-ATPase staining within the stria vascularis was further decreased in the presence of spiral ligament hyalinization. No significant differences were seen with connexin 26 immunostaining. However, immunostaining results were somewhat inconsistent. CONCLUSION: These data suggest that spiral ligament structure and function are essential for stria vascularis survival. In addition, dampened expression of ion transport molecules within the spiral ligament and stria vascularis may disrupt potassium ion recycling, resulting in loss of endocochlear potential and sensory hearing loss.

Aged↗
PubMed1999

The role of the coil click in TMS assessed with simultaneous EEG.

OBJECTIVE: We have used EEG to measure effects of air- and bone-conducted sound from the coil in transcranial magnetic stimulation (TMS). METHODS: Auditory-evoked potentials to TMS were recorded in three different experimental conditions: (1) the coil 2 cm above the head, (2) the coil 2 cm above the head but rigidly connected by a plastic piece to the scalp, (3) the coil pressed against the scalp over the motor cortex. RESULTS: The acoustical click from the TMS coil evoked large auditory potentials, whose amplitude depended critically on the mechanical contact of the coil with the head. CONCLUSION: Both air- and bone-conducted sounds have to be taken into account in the design and interpretation of TMS experiments.

Acoustic Stimulation↗
PubMed2000

Audiological problems in patients with tinnitus exposed to noise and vibrations.

Tinnitus is a hearing sensation appearing without available sound fluctuations in the external environment. It is one of the major, constant and earliest symptoms suggesting different pathology of the hearing analyser. It must be considered, though, that it is evidenced also at disturbed functions of other organs and systems of the organism. The aim of the present study is to elucidate the state of the hearing analyser in patients with tinnitus occupationally exposed to noise and vibrations in relation to therapy. The study was performed on 67 miners, aged 34-55, mean age 44.5 years. The workers with subjective tinnitus (29 persons--43% of the studied group) are the object of this investigation. They were subjected to the following tests of the hearing analyser: pure tone audiometry; above-threshold audiometry (Carhardt's adaptation test, Lusher's differential threshold, SISI test, Kietz test. The evidence reveals that the studied group of workers occupationally exposed to noise, vibrations, dust, toxic substances etc. complain predominantly of tinnitus. It is accompanied by vertigo, headache and disturbed balance. Changes in the hearing function are observed; manifested by different degree of hypacusia concerning air and bone conductivity in the pure tone audiometry. The above-threshold tests also evidence deviations suggesting disturbed hearing function. These changes can be explained by mechanical-toxic pathogenic mechanisms leading to cerebral and vestibular dysfunction most probably of vascular-circulatory type manifested by the above stated deviations. The results are the basis for the following conclusions: 1. The anamnestic profile of workers with tinnitus exposed to noise and vibrations shows a prevalent percentage of vertigo, followed by headache and disturbed balance. 2. The otoneurological profile shows changes in the air and bone conductivity manifested by different degree of hypacusia. 3. The evaluation of the above-threshold tests also confirms the evidence of disturbed hearing function. 4. The relevant therapeutical approach has to be elaborated, having in mind the existing suggestion about the mechanical-toxic etiopathogenesis of the developed process of vascular-circulatory type.

Adult↗
PubMed1976

Alpha 1-antitrypsin activity of perilymph. Occurrence during progression of otospongiosis.

Previous studies by the Adams method demonstrated a strong correlation between hydrolytic enzyme activity of perilymph and progression of bone conduction loss two years preceding stapedectomy. Alpha 1-Antitrypsin was chosen since its activity can be very precisely measured by a radical immunodiffusion technique and since it is one of the enzymes identified in perilymph of patients with active otospongiosis. Samples of 3 mul to 5 mul of perilymph removed during 103 stapedectomies and samples of known alpha 1-trypsin activity were placed on slides coated with alpha 1-antitrypsin serum. The zone of diffusion was stained and measured after 38 hours of incubation. Antitrypsin values were lowest in 24 cases, two with no preoperative bone conduction progression, three with moderate progression of 10 to 15 dB, and 19 with rapid progression of more than 20 dB. They were highest in 36 cases with no progression, and in one case with moderate progression. This study confirms previous reports on the enzymatic activity in otospongiotic disease.

Humans↗
PubMed2002

Comparison of different vibrant soundbridge audioprocessors with conventional hearing AIDS.

OBJECTIVE: To compare the functional gain of different Symphonix Soundbridge audioprocessors (HF-processor and D-processor) to preoperatively fitted conventional hearing aids of patients with mild to severe sensorineural hearing loss in the high-frequency range. STUDY DESIGN: In a prospective study, the Symphonix Soundbridge (HF-processor and D-processor) fitting results were evaluated and compared with conventional hearing aids. Postoperative air and bone conductances, the functional gain of warble-tone measurements, speech audiometric, and subjective outcome testing (Abbreviated Profile of Hearing Aid Benefit questionnaire) were studied. SETTING: Tertiary referral center. PATIENTS: Five patients (ages, 54-69 yr) with mild to severe sensorineural deafness in the high-frequency range, but no progression of hearing loss during the last two years, were initially fitted with the so-called HF-processor, then subsequently fitted with the D-processor, which was a fully digital one. RESULTS: One year after implantation of the Symphonix Soundbridge device, unchanged, stable air and bone conductances were found (except for one minor change). Over the whole frequency range (0.5-8.0 kHz), a mean gain of 16.1 dB (HF-processor), 27.1 dB (D-processor), and 15.2 dB (hearing aid) was found. The Symphonix Soundbridge device with different audioprocessors led to improved hearing in speech audiometric testing. The data show a significant improvement of hearing compared with conventional hearing aids in quiet, and a better functional gain in noise for the Symphonix Soundbridge system. The Abbreviated Profile of Hearing Aid Benefit questionnaire also revealed that the implant resulted in significant differences compared with conventional hearing aids in almost all subcategories. CONCLUSION: The Symphonix Soundbridge device can improve the hearing benefit of moderately to severely hearing handicapped patients-particularly in those with a high-frequency hearing loss-when compared with the conventional hearing aids of these patients, as evidenced by objective and subjective measurements. The Symphonix Soundbridge D-processor showed further improvements and resulted in an additional hearing benefit that was superior to that of the previously fitted HF-audioprocessor. This is owing to the refinements and upgrades in audioprocessor technology.

Acoustic Stimulation↗
PubMed1997

Surface modifications of titanium in calcium-ion-containing solutions.

The surface of titanium was modified in calcium-ion-containing solutions to improve bone conductivity. Three kinds of aqueous solutions for the modification were prepared using calcium nitrate, calcium chloride, and calcium oxide. The pH values of the solutions were 3.9, 7.4, and 12.6, respectively. At first, anatase powder was immersed in the solutions of 7 days to confirm the effect of the solutions on the modification. As a result, calcium titanate was formed on the anatase powder, indicating that the titanium surface was possibly modified by the solutions. Titanium plates were then immersed in the solutions at ambient temperature for 7 days, washed by deionized water, and dried. X-ray photo-electron spectroscopy of surface-modified titanium revealed that the surface-modified layer contained calcium hydroxide and/or calcium titanate. The surface-modified layer in which titanium was modified was thickest in this order: calcium oxide, calcium chloride, and calcium nitrate solutions. Apatite was formed on the surface-modified titanium in Hanks' solution while apatite was undetected on unmodified titanium. Therefore, the surface modification of titanium may improve bone conductivity. The amount of apatite corresponded to the thickness of the surface-modified layer and the amount of calcium in the layer.

Apatites↗
PubMed2002

Stapedotomy for tympanosclerotic stapes fixation: is it safe and efficient? A review of 68 cases.

OBJECTIVE: Performing stapedotomy in cases of tympanosclerotic stapes fixation is controversial. The procedure is traditionally considered to carry a high risk of postoperative sensorineural hearing loss. The aim of this study was to report the hearing results in surgically treated cases of stapes fixation. STUDY DESIGN: A retrospective review of tympanosclerosis of the oval window with stapes fixation. SETTING: The study was performed at the Jean Causse Ear Clinic in Clombiers, France. PATIENTS: Sixty-five patients who underwent surgery for tympanosclerotic stapes fixation between January 1992 and October 1999. INTERVENTION: Stapedotomy with vein graft interposition and reconstruction with a Teflon piston, or a total prosthesis in cases of incudal erosion. MAIN OUTCOME MEASURES: Preoperative and postoperative audiometric evaluation using conventional audiometry. Air-bone gap, bone conduction threshold, air conduction threshold, and Glasgow Benefit Plot were measured. RESULTS: Postoperative air-bone gap closure to within 10 dB was achieved in 39% of cases. An air-bone gap less than 20 dB was obtained in 70% of cases. Significant postoperative improvement of air conduction thresholds, more than 20 dB, was found in 46% of cases. The postoperative bone conduction thresholds were unchanged in 92% of cases. No significant sensorineural hearing loss was seen in this series. CONCLUSION: This series demonstrates that safe and successful stapedotomy is possible if certain rules are respected.

Adolescent↗
PubMed1999

Clinical presentation and management of labyrinthine fistula caused by chronic otitis media.

To describe the clinical presentation and surgical management of patients with chronic otitis media complicated by labyrinthine fistula and to determine clinical indicators that predict postoperative hearing outcome, I performed a retrospective analysis at an academic tertiary care center. Thirty-four patients with labyrinthine fistula as a complication of chronic otitis media, documented at mastoidectomy, underwent postoperative audiometry. The median age was 50 years, and the duration of otologic symptoms ranged from 2 months to more than 40 years. On presentation, 3 patients had anacusis in the affected ear, while in the others, the pure tone average for bone conduction at the 0.5-, 1-, 2-, and 4-kHz frequencies was 34 dB hearing level. Nineteen patients (56%) complained of dizziness on presentation. The fistula test was positive in 14 of 28 patients (50%). The fistula was detected radiologically in 10 of 24 patients (42%). Cholesteatoma was present in 33 of 34 patients (97%). The lateral semicircular canal was the most common site of labyrinthine fistula. The cholesteatoma matrix was completely removed in 29 of 33 cases and exteriorized in the remaining 4. Of the 31 patients with measurable hearing preoperatively, anacusis occurred in 8 (26%). In 6 of these, the preoperative pure tone average for bone conduction was greater than 50 dB hearing level, and cholesteatoma matrix and granulation tissue invading the membranous labyrinth were found at surgery. I concluded that in chronic otitis media, labyrinthine fistulas occurred almost exclusively in the presence of a cholesteatoma. Postoperative hearing outcome correlated with the size of the fistula and the presence of granulation tissue invading the labyrinth. which could be predicted by the preoperative audiometry.

Adolescent↗
PubMed2005

[Diagnosis and surgical management of labyrinthine fistula caused by cholesteatoma].

OBJECTIVE: To describe the clinical presentation and surgical management of patients with labyrinthine fistula caused by cholesteatoma. METHOD: Retrospective study of the clinical presentation, surgical technique and hearing outcomes based on 350 cases of chronic otitis media with cholesteatoma was carried out. Twenty three patients (6.6%) with labyrinthine fistula were found, in 9 ears (39.1%) the preoperative pure tone average for bone conduction was greater than normal, including 2 cases of analysis. Subjective vertigo or dizziness occurred in 11 patients (47.8%), the fistula test was positive in 5 patients (21.7%). Preoperative high resolution computed tomography (HRCT) scans were performed on all patients and 13 patients (57%) were detected to be with labyrinthine fistula in imaging. During the operation we found the lateral semicircular canal was the most commonly affected site (20/23), at the same time dehiscence of the facial canal was observed in 8 patients. RESULT: The patients were followed-up for an average time of 2 years, dizziness disappeared completely in 22 cases and there were no significant changes in their bone conduction thresholds. CONCLUSION: Labyrinthine fistulae are usually caused by cholesteatoma. There are no reliable methods at present for preoperative diagnosis HRCT is useful but its limitations should also be recognized. The verification of a labyrinthine fistula can be definitively established only at the time of surgery. Completely remove the cholesteatoma matrix can be the treatment of choice in these cases.

Adolescent↗
PubMed2005

Characteristics and clinical applications of vestibular-evoked myogenic potentials.

A recent technique of assessing vestibular function, the vestibular-evoked myogenic potential (VEMP), is an otolith-mediated, short-latency reflex recorded from averaged sternocleidomastoid electromyography in response to intense auditory clicks delivered via headphones. Since their first description 10 years ago, VEMPs are now being used by investigators worldwide, and characteristic changes observed with aging and in a variety of peripheral and central vestibulopathies have been described. Additional methods of evoking VEMPs, which use air- and bone-conducted short-tone bursts, forehead taps, and short-duration transmastoid direct current (DC) stimulation, have been described, and these complement the original technique. Click-evoked VEMPs are attenuated or absent in a proportion of patients with vestibular neuritis, herpes zoster oticus, late Meniere disease, and vestibular schwannomas; their amplitudes are increased and thresholds are pathologically lowered in superior semicircular canal dehiscence presenting with the Tullio phenomenon. VEMPs evoked by clicks and DC are useful when monitoring the efficacy of intratympanic gentamicin therapy used for chemical vestibular ablation. Prolonged p13 and n23 peak latencies and decreased amplitudes have been observed in association with central vestibulopathy. VEMPs evoked by clicks are a robust, reproducible screening test of otolith function. DC stimulation enables differentiation of labyrinthine from retrolabyrinthine lesions; bone-conducted stimuli permit VEMP recording despite conductive hearing loss and deliver a relatively larger vestibular stimulus for a given level of auditory perception.

Acoustic Stimulation↗
PubMed1999

[Labyrinthine fistulas in cholesteatoma].

The purpose of the present study was to investigate the clinical features of cases of cholesteatoma with labyrinthine fistulas, and in particular the pre and post-operative bone-conduction (BC). Cholestatoma patients with bone erosion or a defect found in the first stage operation were analyzed. The operations were conducted between 1992 and 1996. The patients were classified into four types, I, IIa, IIb, and III, according to Dornhoffer and Milewski's classification, which is based on different stages in the bone defect. A type I fistula is an erosion of the bony labyrinth with an intact endosteum. Type IIa is accompanied by an opened perilymphatic space with undisturbed perilymph while type IIb has a disturbed perilymph. A Type III fistula is an opened perilymphatic space with a disturbance of the underlying membranous labyrinth. Only 24 patients with type II and type III fistulas were included in this study. The location of the fistulas was the semicircular canals (SCCs) or/and the vestibula in 21 patients and in the cochlea in 3 patients. We examined the fistula by high-resolution computed tomography scan (CT scan) with 1 mm slice and 1 mm width axial-sections in 14 patients. A bone defect in the labyrinth was detected in 10 cases (71.5%) pre-operatively. Pre-operative BC was worse in the patients with cochlear fistulas than in those with fistulas located in SCCs or the vestibula. Within this latter group there were 13 type IIa (group IIa), patients and 8 type IIb or III (group IIb or III) patients. However, there was no difference in the pre-operative BC between these two sub-groups Tympanoplasty was conducted in all 24 patients. The postoperative BC of group IIa and group IIb or III were compared. Two of the 13 patients in group II a (15.4%) and 3 of 8 in group IIb or III (37.5%) had a deteriorated postoperative BC. Statistical analysis revealed that the postoperative BC was more inclined to become worse in patients with advanced stage IIb or III fistulas.

Adolescent↗
PubMed1996

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.

Cochlea↗