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Stapedectomy for otosclerosis with malleus fixation.

Malleus fixation, in addition to stapes fixation, presents a perplexing surgical problem. Should the incus replacement prosthesis procedure be performed or only a stapedectomy? The hearing results of a stapedectomy alone in 45 cases with both stapes and malleus fixation are 70% within 10 dB and 84% within 20 dB of the preoperative bone conduction hearing level.

Bone Conduction↗

Clinical findings and diagnostic problems in sensorineural low frequency hearing loss.

The otological and audiological findings in 39 patients with sensorineural low frequency hearing loss are reported. This type of perceptive hearing loss is difficult to distinguish from the true conductive hearing losses due to the air conduction audiogram shape and the invalidity of bone conduction determinations showing a false "air-bone gap". This may lead to surgical treatment of a perceptive hearing loss, as reported in the four case histories. By various audiological tests, contradictory information may be obtained. In our material, Bing's test and absent acoustic reflexes indicated a conductive disorder in 25% of the ears. The final differentiation may require cochleography. The hearing loss may be diagnosed as Meniere's disease. In our material only 17% complained of tinnitus and no patients had vertigo. Consequently, we find sensorineural low frequency hearing loss to differ from Meniere's disease. Our material comprises different etiological types of perceptive low frequency hearing loss. On type was inherited as an autosomal dominant trait, another type due to cochlear malformation probably also inherited, and a third group showing diverse audiological results. When the diagnosis is established, the patients may be treated successfully by specially constructed hearing aids.

Adolescent↗

Argon laser in difficult stapedotomy cases.

OBJECTIVE: The success and safety of argon lasers in stapedotomy surgery is now well documented. This study reviews results in problematic situations in which the argon laser may be of particular advantage to successful completion of the stapedotomy procedure. STUDY DESIGN: Retrospective chart review. METHODS: A retrospective review of the author's most recent 200 stapedotomy cases was performed, identifying 32 patients who at surgery were either found to have a prolapsed dehiscent facial nerve (three cases), developed a floating footplate (eight cases), or were undergoing a revision stapedotomy (21 cases). Four-frequency, pure-tone average air and bone conduction thresholds were computed before and after surgery. Success was defined as closure of the air-bone gap to within 10 dB, while an air-bone gap within 20 dB was considered improvement. RESULTS: Successful closure of the air-bone gap was achieved in all eight patients with a mobilized footplate, in all three patients with a prolapsed dehiscent facial nerve, and in 43% of the patients undergoing a revision stapedotomy. The rate of improved air-bone gap in the revision cases was 62%. In one revision stapedotomy patient a decrease in speech discrimination occurred. Otherwise, there were no cases of sensorineural hearing loss. Neither intraoperative nor postoperative dizziness was reported by any patient, and all were discharged on an outpatient basis. CONCLUSION: The argon laser was found to be safe, effective, and a valuable adjunct for the difficult stapedotomy cases when unexpected obstacles such as a prolapsed dehiscent facial nerve or a mobilized footplate are encountered, as well as for the planned, more difficult revision cases.

Adult↗

[Some remarks concerning the treatment of the conductive hearing loss].

The author points out a decrease tendency in using middle ear reconstruction surgery due to the development and the accessibility of hearing aids. Such an attitude inevitably leads to ordering hearing aids especially air conductive ones in cases which ought to be operated. The author thus wants to underline the fact that bone conductive hearing aids are very rarely recommended, even though the should be used more often. He also recommends a precise analysis of one's unsuccessful surgical results as a method of gaining skills and proficiency. The author also points out the fact that one should never neglect quoting native bibliography.

Bone Conduction↗

Frequency-specific audiometry using steady-state responses.

OBJECTIVE: To evaluate the audiometric usefulness of steady-state responses to multiple simultaneous tones, amplitude-modulated at 75 to 110 Hz. DESIGN: Steady-state responses to multiple tones amplitude-modulated at different rates between 75 and 110 Hz and presented simultaneously were recorded at different intensities in normal adults, well babies, normal adults with simulated hearing loss, and adolescents with known hearing losses. Response thresholds were compared with behavioral thresholds. RESULTS: In normal adults the thresholds for steady-state responses to tones of 0.5, 1, 2, and 4 kHz were 14 +/- 11, 12 +/- 11, 11 +/- 8, and 13 +/- 11 dB, respectively, above behavioral thresholds for air-conducted stimuli, and 11 +/- 5, 14 +/- 8, 9 +/- 8, and 10 +/- 10 dB above behavioral thresholds for bone-conducted stimuli. In well babies tested in a quiet environment, the thresholds were 45 +/- 13, 29 +/- 10, 26 +/- 8, and 29 +/- 10 dB SPL. In adolescents with known hearing losses, the steady-state responses thresholds predict behavioral thresholds with correlation coefficients (r) of 0.72, 0.70, 0.76, and 0.91 at 0.5, 1, 2, and 4 kHz, respectively. CONCLUSION: Steady-state responses to tone amplitude-modulated at 75 to 110 Hz can be used for frequency-specific objective audiometry. The multiple-stimulus technique allows thresholds to be estimated for eight different stimuli at the same time.

Adolescent↗

Predictive role of Carhart's notch in pre-operative assessment for middle-ear surgery.

OBJECTIVES: To evaluate the predictive role of the audiometric Carhart's notch for the assessment of middle-ear pathology prior to surgical intervention. METHOD: In this retrospective analysis, a total of 315 operated ears of 305 patients were evaluated regarding their pre-operative pure tone audiograms and peri-operative findings. The probable relationship between the middle-ear pathologies found and the Carhart's notch found on pre-operative pure tone audiometry was investigated. Patients with conductive hearing loss who obtained at least a 10 dB improvement (at 1 and 2 kHz frequencies) in their bone conduction threshold post-operatively were included in the Carhart's notch group. The pathologies underlying Carhart's notch were compared. RESULTS: Three hundred and fifteen ears of 305 consecutive patients with conductive hearing loss were operated on due to middle-ear pathology. In patients with otosclerosis and tympanosclerosis, a Carhart's notch was seen at 2 kHz in 28 (93 per cent) patients but at 1 kHz in only two (7 per cent). However, in patients with chronic otitis media, a Carhart's notch was seen at 1 kHz in 10 (55 per cent) patients and at 2 kHz in eight (45 per cent) patients. CONCLUSIONS: Otitis media with effusion, tympanosclerosis and congenital malformations should be considered in the differential diagnosis of a patient with a Carhart's notch seen on pure tone audiometry. A Carhart's notch at 2 kHz indicates stapes footplate fixation, whereas one at 1 kHz indicates a mobile stapes footplate; the footplate mobility can thus be predicted pre-operatively.

Adolescent↗

Clinical results of percutaneous implants in the temporal bone.

The bone-anchored hearing aid is an alternative to the conventional bone-conduction hearing aid, without the disadvantages of pressure pain or skin irritation and with direct sound transmission to the skull. The bone-anchored hearing aid is coupled to a percutaneous titanium implant, which is placed in the mastoid process in two surgical stages. We analyzed the clinical results of 68 percutaneous implants in 65 patients. After a follow-up period of 8 to 45 months, 97% of the implants were anchored in the bone. In 86% of the implants, no potentially dangerous skin reactions occurred. The occurrence of skin reactions was not time dependent. Movement of the skin, thick skin, and poor skin condition around the implant were related to the onset of skin reactions. This study showed that the percutaneous titanium implant forms a stable link between the bone-anchored hearing aid and the skull.

Adolescent↗

Stapedotomy in osteogenesis imperfecta patients.

Osteogenesis imperfecta (OI) is a connective tissue disorder characterized by osseous fragility, blue sclerae and hearing loss. In order to assess the impact of stapedotomy on improving hearing on OI, a retrospective, one-group, pre-test-post-test design was used to compare the pre-operative and post-operative audiograms of nine OI patients, treated with stapedotomy for their mixed hearing loss. Operative findings included fixation or thickening of the stapes footplate with normal superstructure configuration and hypervascularization of the promontory mucosa. Immediate post-operative results showed a significant improvement (p < 0.05) from 250-4000 Hz in air conduction and from 250-2000 Hz in bone conduction. A significant closure of the air-bone gap between 250-2000 Hz was also achieved (p < 0.05). The long-term results remained satisfactory with a mean threshold shift of 8 dB HL and an almost unchanged air-bone gap. These satisfactory results and the lack of complications make stapedotomy an appealing method for the management of OI-associated hearing loss.

Adult↗

A one-stage surgical procedure for placement of percutaneous implants for the bone-anchored hearing aid.

The bone-anchored hearing aid (BAHA) is an alternative to the conventional bone conduction hearing aid. The transducer is coupled to a percutaneous titanium implant which is traditionally inserted into the temporal bone in two stages. This study focusses on a one-stage surgical technique for the implantation of percutaneous implants. The preliminary clinical results of 33 one-stage implants in 33 patients are presented. Post-operative necrosis of the skin grafts did not occur. After a follow-up which varied from nine to 25 months, 31 out of the 33 fixtures (94 per cent) were anchored firmly in the skull. Twenty-six out of the 33 implants (79 per cent) remained free from potentially dangerous skin reactions. The results were statistically comparable to those obtained with two-stage implants at the same clinic. Although longer follow-up is needed before a general statement can be made about replacing the two-stage technique, the preliminary one-stage results are promising.

Adolescent↗

Malleus relocation in ossicular reconstruction: managing the anteriorly positioned malleus: results in a series of 268 cases.

OBJECTIVE: The objective of this study was to report an original method of malleus relocation allowing for better placement of both partial and total prostheses in ossicular reconstruction. STUDY DESIGN: We conducted a retrospective review of clinical and audiometric findings. SETTING: A tertiary referral center. MATERIALS AND METHODS: This is a study of 268 patients who underwent ossiculoplasty surgery from October 1997 to October 2000 for chronic otitis media, noninflammatory disease, and otosclerosis revision. Malleus relocation with total and partial ossicular replacement prostheses was used in all cases. Audiometric assessment included pre- and postoperative audiometric evaluation using conventional audiometry. Air-bone gap, bone-conduction thresholds, and air-conduction thresholds were measured. RESULTS: A postoperative air-bone gap closed to within 10 dB was achieved in 56% of cases. An air-bone gap smaller than 20 dB was obtained in 78% of cases. Postoperative improvement of air-conduction thresholds superior to 20 dB was found in 41.5% of cases. The postoperative bone-conduction thresholds were unchanged in 98% of cases. One case of total postoperative sensorineural hearing loss was seen in this series (0.4%). Extrusion of the protheses was not observed in this series. Follow up ranged from 6 to 36 months (mean, 12.4 months). CONCLUSION: This study shows that malleus relocation is a safe and efficient technique for ossicular reconstruction. The ideal position of the relocated malleus allows easier and more stable placement of middle ear prostheses.

Adolescent↗

Ten years of experience with the Swedish bone-anchored hearing system.

In 1977, a new phase began in hearing rehabilitation of patients with chronic middle and external diseases and atresias. Thus far, these patients have had to rely on conventional bone conduction and air conduction devices that for various reasons give poor rehabilitation. The principle of the new treatment, made possible by the Swedish bone-anchored hearing system, is simple: sound vibrations are directly transmitted to the skull bone via a skin-penetrating titanium implant and then are further transmitted to the cochlea, bypassing the middle ear. The present paper summarizes our results in 147 patients over 10 years, including a total of 6,334 follow-up months. No significant rate of skin infections was observed. In over 93% of the observations, no sign of adverse skin reaction was seen. When herein-suggested indications for treatment with the bone-anchored sound processor HC-200 are followed, the success rate is over 90%. The improved quality of life reported by the patients is a combination of improved quality of sound, improved comfort, and relief from middle ear and ear canal disease occasioned by conventional hearing aids.

Adolescent↗

Stapedectomy trends for the resident.

The diminishing number of cases of otosclerosis limits the training experience in stapes surgery during residency. Results are suboptimal. Closure of the preoperative air conduction to within 10 dB of bone conduction was obtained in only 64% of resident cases. Efforts to maximize experience and improve results include closer faculty supervision, use of one stapedectomy technique, and a prospective study of individual residents' performance.

Adolescent↗

Ethene oxide and bone induction. Controversy remains.

There is controversy as to whether ethene oxide ("ethylene oxide", EO) sterilization destroys the bone-inducing capacity of demineralized bone matrix (DBM) or not. Correctly performed studies seem to support both opinions. Bone conductive properties of fresh frozen, defatted bone grafts are greatly impaired by EO sterilization, whereas purified inductive proteins resist EO. Studies showing destruction of osteoinductive capacity used nonpulverized DBM, whereas the others used powder. This could be the key to resolving the controversy, because if EO treatment reduces the cells' ability to penetrate a cortical graft and to reach inductive proteins inside it, it may appear noninductive after EO sterilization, even though BMP molecules may be intact. On the other hand, cells could easily penetrate the powder implants. We compared the effect of EO sterilization on the inductive capacity of demineralized cortical bone with that of DBM powder, using allogeneic material in rats. Cortical pieces lost all inductive capacity by EO sterilization, whereas the powder yielded a calcium content which was at best one fourth of the unsterilized. The concentrations of residual EO, ethene chlorohydrin and ethene glucol at implantation were far below approved levels. Another difference between studies is the humidity during EO treatment. In our hands, humidification reduced bone yield by half. In conclusion, EO sterilization may impair the biological performance of bone inductive implants by reducing cell penetration into bulk material. However, DBM powder, when correctly sterilized, also yielded scanty amounts of bone.

Animals↗

[DPOAE otoemission in patients with tinnitus and normal hearing].

The goal of our study was analysis of characteristic interrogation, audiometry and distortion products otoacoustic emission in patients with normal hearing and complaining of tinnitus. We examined the group of 24 ill patients with hearing threshold up till 25 dB HL and with tinnitus and the control group of 18 with no audiological complains. All the patients were made tonal audiometry and the discomfort level as well as tinnitus frequency and intensity were evaluated. For each ear separately, we examined DPAOE of DP-gram function with resolving power of half the octave and the fine structure on the level of stimulation L1 = L2 = 70 dB. In the group of patients average time of tinnitus was 1.5 year. Average hearing threshold in patients with tinnitus was 18 dB HL for air conduction and 11 dB HL for bone conduction, average discomfort threshold--93 dB HL. In the control group hearing threshold was comparatively 16 dB and 10 dB HL and average discomfort threshold--95 dB HL. In the tinnitus group 8 patients (21%) complained of hyperacusis. The differences between the two groups in DP-gram were observed mainly in high frequencies (higher than 3000 Hz). In DP-gram fine structure in the group of patients with tinnitus we noted wider span of otoemission decreases (over the octave) compared to control group. In the tinnitus group among 20 examined ears with decreases of otoacoustic emission DP--fine structure only in 6 patients (30%) the frequency of tinnitus given by the patient was overlapping with the frequency for which decreases of otoemission were observed. In both groups we observed decreases of DPOAE for some frequencies but in the patients with tinnitus we noticed the lack of otoacoustic emission in wider span of frequencies, mainly in higher frequencies compared to controls.

Adult↗

Acoustic basis of tuning fork tests.

OBJECTIVES: To obtain pilot data to determine the feasibility of supporting or refuting a theory regarding lateralization of sound in conductive hearing loss and to describe the application of this theory to other tuning fork tests. DESIGN: Controlled audiometric testing with and without a conductive hearing loss. SETTING: A tertiary medical centre. METHODS: Sound pressure levels in external auditory canals were measured during presentation of 40- and 50-dB bone-conducted stimuli. Measurements were taken from five normal male subjects before and after inducing a conductive hearing loss. OUTCOME MEASURES: If sound intensity in the ear canal was greater in the unobstructed ear canal than the obstructed ear canal, the hypothesis was supported. The number of subjects required to provide definitive proof was calculated from the measured intensity difference with and without the conductive loss and the intrasubject variability of sound intensity measurements. The applicability of the theory to other tuning fork tests and auditory phenomena was explored. RESULTS AND CONCLUSIONS: A total of 600 subjects would be required to provide evidence to support our theory using this method. The acoustic impedance mismatch-reflected sound theory could be applied to other tuning fork tests, but until further proof is available, it must be considered only a theory.

Acoustic Impedance Tests↗

The effect of drinking water fluoridation on the natural course of hearing in patients with otosclerosis.

The effect of drinking water fluoridation on the course of hearing of non-operated otosclerotic ears was assessed in an area where the natural waters have a very low fluoride content. The study population consisted of 150 patients with surgically proven otosclerosis. Patients having an additional known cause of hearing loss were excluded from the study. Every patient had a follow-up of at least 5 years, the mean follow-up period being 8.8 years. At last follow-up examination, air conduction thresholds of patients drinking fluoridated tap water were found to be significantly better than those of patients drinking fluoride-poor water, likewise there were significant differences in bone conduction thresholds at 1, 2, and 4 kHz. It was concluded that drinking water fluoridation has a beneficial effect on hearing levels of non-operated otosclerotic ears.

Adult↗

Sensorineural and pseudosensorineural hearing losses.

This paper describes, on the basis of animal experiments, that Carhart's notch is caused either by ossicular-chain defects or by stapedial mass-loading. Thus, not all bone conduction impairments are an indication of sensorineural hearing losses, i.e., inner-ear defects.

Animals↗

A reevaluation of the 512-Hz Rinne tuning fork test as a patient selection criterion for laser stapedotomy.

OBJECTIVE: This study aimed to challenge the classical hypothesis that a negative preoperative 512-Hz Rinne tuning fork test (bone conduction greater than air conduction) is a necessary condition to allow consistent objective and subjective hearing improvement with surgery for otosclerosis. STUDY DESIGN: The study design was retrospective (chart review and questionnaire). SETTING: The study was conducted at a Florida Ear and Sinus Center at Sarasota, Florida, a tertiary otology-neurotology referral center. PATIENTS: Patients who underwent primary laser stapedotomy with equivocal (air=bone) preoperative 512-Hz Rinne test results participated. INTERVENTION: KTP laser stapedotomy was performed. MAIN OUTCOME MEASURES: Audiologic measurements of air-bone gap closure and patient assessment of hearing improvement and satisfaction were conducted. RESULTS: The air-bone gap was closed to within 10 dB in all cases. There were no complications. Eighteen patients were questioned about their results. Hearing improvement was subjectively described as "excellent" or "good" by 17 (94%), and 16 (89%) thought the surgery was "absolutely" worthwhile. CONCLUSIONS: The preoperative 512-Hz Rinne test results need not be negative to achieve significant air-bone gap closure and subjective appreciation of improved hearing.

Audiometry↗