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PubMedDate not supplied

Prescription of hearing aids: a rationale.

A rationale is presented for a hearing aid prescription. Once the choice of ear(s) to be fitted is determined and whether air or bone conduction fitting is appropriate, output and gain-frequency response characteristics are prescribed on the basis of audiometric test data. The specific prescription data for ouptut are based on uncomfortable loudness levels, and gain-frequency response data are based on a formula that was determined by imposing typical speech parameters over a given hearing loss. A hearing aid prescription is not only intended to predict amplification needs but, just as important, it also provides a method for testing the results of those predictions.

Audiometry↗
PubMed1999

[Age-specific structural features of the nasal septum in children].

Hearing was studied in 20 and 34 patients with subclinical and initial renal failure (RF), respectively. RF was secondary to chronic glomerulonephritis, chronic pyelonephritis, renal polycystosis (29, 24 and 1 patients, respectively). Hearing function was assessed at tonal threshold, suprathreshold and speech audiometry, ultrasound investigations. It was found that one third of the patients had bilateral symmetric hearing disorder of neurosensory hypoacusis type. The affection was not severe but involved both peripheral and central compartments of the acoustic analyzer. High-frequency sound sensitivity suffered most of all. There was a rise in hearing thresholds by air and bone conductivity at frequencies 12-18 kHz. This rise was the only marker of affected acoustic analyzer in 39% of the examinees. 12% of the patients demonstrated elevated hearing thresholds combined with elevated ultrasound thresholds, low differential threshold of sound intensity and abnormal threshold adaptation.

Adolescent↗
PubMed1999

Footprints of the globe: a practical look at the mechanism of orbital blowout fractures, with a revisit to the work of Raymond Pfeiffer.

Multiple mechanisms of orbital blowout fractures have been proposed since the fracture was described at the beginning of this century. The original theory of direct globe-to-wall contact was abandoned long ago for the more contemporary hydraulic and bone conduction theories. Although the more widely accepted theories play an obvious role in fracture generation and its associated complications, it is our contention that direct globe-to-wall contact is an important and largely unrecognized mechanism in orbital blowout fracture production. By means of a critical review of the historical literature and an analysis of patient computed tomography scans, support is presented for the original theory first proposed by Raymond Pfeiffer in 1943.

Humans↗
PubMed1998

[Progressive sensorineural hearing loss in cochlear otosclerosis].

Otosclerosis is a bone dysplasia limited to the otic capsule causing abnormal resorption and redeposition of bone. The existence of the entity "pure labyrinthine otosclerosis" or "cochlear otosclerosis" is not accepted by all authors; however, there is clinical and histologic evidence to support the existence of a progressive sensorineural hearing loss due to otospongiotic-otosclerotic lesions of the labyrinthine capsule, although diagnosis of this condition may be difficult. The involvement of the inner ear is described as degenerative changes in the spiral ligament, stria vascularis, organ of Corti, and cochlear neurons. The most frequent audiometric configuration is a "bite-type" curve, but flat or rising shapes can also be observed; speech discrimination appears unusually good for a pure sensorineural hearing loss and recruitment is frequently absent. A cochlear otosclerosis should be suspected when there is a family history of otosclerosis, the onset of the hearing loss occurs from the third to fifth decade, and worsening of the hearing loss is observed during periods of intense hormonal and endocrine activity, a positive Schwartze sign is present and bilateral sensorineural loss is associated with signs of unilateral stapedial ankylosis. A definitive diagnosis of cochlear otosclerosis can be made only with computed tomography, which allows a quantitative assessment of the involvement of the labyrinthine capsule by spongiotic or sclerotic areas. The factors to be considered are: otosclerotic foci 1 mm or more in diameter and a density different from that of the normal otic capsule, partially or completely erased contour of the capsule, double ring effect, bony neoformation in the labyrinthine spaces, and increased thickness of the cochlear capsule. The medical management of cochlear otosclerosis is based on sodium fluoride, in association with calcium and vitamin D; some authors have also proposed diphosphonates as inhibitor agents of bone resorption. Surgery may be useful only in those patients presenting a hearing loss so severe that the bone threshold cannot be evaluated and a gap between air and bone conduction cannot be excluded; in these cases stapes operations can improve hearing to a level that may be useful in hearing aid application.

Cochlea↗
PubMed2000

Pure tone audiogram and speech audiometry in patients with hereditary motor and sensory neuropathy.

The goal of our work was to determine hearing thresholds in patients with hearing impairment due to hereditary motor and sensory neuropathy (HMSN I). In assessment of auditory function we used two methods: pure tone and speech audiometry. Pure tone audiometry was performed using air and bone conducted signals. Speech comprehension was defined with a test battery of monosyllabic words unknown to the patient. By comparing the results of these methods we were able to differentiate whether the hearing loss was of cochlear or retrocochlear origin. We tested 5 patients with HMSN I associated with difficulty in speech understanding. The tests showed mild to severe elevation of pure tone thresholds but no speech perception in any of tested patients. We suggest that this type of hearing impairment be due to the disorder of the auditory nerve function--a neuropathy of the auditory nerve as part of HMSN.

Adolescent↗
PubMed2000

Comparison of ofloxacin otic solution with oral amoxycillin plus chloramphenicol ear drop in treatment of chronic suppurative otitis media with acute exacerbation.

The efficacy and safety of 0.3 per cent Ofloxacin otic solution (OFLX) 6 drops twice daily was compared with those of oral Amoxycillin 500 mg three times daily plus 1 per cent Chloramphenicol ear drop at 3 drops three times daily (AMOX + CRP) in a two-week treatment of chronic suppurative otitis media (CSOM) with acute exacerbation. 80 adult patients were enrolled in a prospective, randomized, investigator-blind study at the outpatient ENT service of Chulalongkorn University Hospital. The most common pathogens isolated at the pretreatment visit were Staphylococcus aureus (30.3%) and Pseudomonas aeruginosa (24.7%). The susceptibility of all the pathogenic isolates to ofloxacin, amoxycillin and chloramphenicol were 96.4, 57.1 and 51.8 per cent respectively. The overall response expressed as an improvement or cure of otalgia, otorrhea and middle ear mucosal inflammation was recorded. It revealed that the improvement rate of the OFLX-treated patients was better than that of AMOX + CRP-treated, but was not statistically significant. However, the cure rate was significantly better in OFLX-treated than in AMOX + CRP-treated groups in terms of painless (p = 0.05) and dry (p < 0.001) ears. Ototoxicity was assessed by an elevation in bone conduction threshold (BC) and/or speech reception threshold (SRT) of greater than 5 dB or a presence of high tone hearing loss resulting from treatments. A significant decrease in BC and SRT was revealed in OFLX-treated ears (p < 0.0001; p = 0.002 respectively) but a significant elevation of BC was found in AMOX + CRP-treated ears (p = 0.007). The ototoxic rate was significantly higher in AMOX + CRP-treated than in OFLX-treated ears whether assessed by BC (p < 0.001) or SRT (p = 0.03). In conclusion, OFLX was more effective and safer than AMOX + CRP in the treatment of CSOM with acute exacerbation.

Administration, Oral↗
PubMed2000

[Mastoid cortical bone grafts in ossiculoplasty].

Ossicular homografts have been left for safety reasons with regard to viral transmission diseases. Several means are usable to reconstruct ossicular chain: synthetic prosthesis and autologous bone. On grounds of disponibility, biocompatibility, cost and use easiness we have been using mastoid cortical bone since 1995. We have studied hearing results and tolerance of 45 ossiculoplasties performed with cortical bone. Two years after, we have been obtaining as good or even better functional results with cortical bone graft than with auto or homologous ossicular bones (air bone gap inferior or equal to 20 DB in 89 % of the cases) and no extrusion. Thus, cortical bone seems to be, the better material when autologous ossicular bones are not available.

Adolescent↗
PubMed1997

[Partial stapedectomy with CO2 laser].

For the efficacy and safety of partial stapedectomy, Co2 laser was used in 44 patients with otosclerosis. Postoperative follow-up (3-12 months) demonstrated that the average hearing gain was 31.7 +/- 8.2 dB, and air-bone conduction gap was within 11.2 +/- 6.6 dB. There was no significant hearing change at 4.000 Hz. The advantages of CO2 laser technique are summarized as follows: convenience for cutting posterior crus, less time needed for penetration of thick footplate or removal of occlusive sclerotic plaque in oval window niche, avoidance of footplate floating, rapid coagulation of residual stapedial artery and absence of instrumentation difficulties in narrow spaces. Our results indicate that CO2 laser provides essential benefits in stapedectomy for otosclerosis.

Adult↗
PubMed1999

Correlations between audiogram and objective hearing tests in sensorineural hearing loss.

Owing to its subjective nature, behavioral pure-tone audiometry often is an unreliable testing method in uncooperative subjects, and assessing the true hearing threshold becomes difficult. In such cases, objective tests are used for hearing-threshold determination (i.e., auditory brainstem evoked potentials [ABEP] and frequency-specific auditory evoked potentials: slow negative response at 10 msec [SN-10]). The purpose of this study was to evaluate the correlation between pure-tone audiogram shape and the predictive accuracy of SN-10 and ABEP in normal controls and in patients suffering from sensorineural hearing loss (SNHL). One-hundred-and-fifty subjects aged 15 to 70, some with normal hearing and the remainder with SNHL, were tested prospectively in a double-blind design. The battery of tests included pure-tone audiometry (air and bone conduction), speech reception threshold, ABEP, and SN-10. Patients with SNHL were divided into four categories according to audiogram shape (i.e., flat, ascending, descending, and all other shapes). The results showed that ABEP predicts behavioral thresholds at 3 kHz and 4 kHz in cases of high-frequency hearing loss. Also demonstrated was that ABEP threshold estimation at 3 kHz was not affected significantly by audiogram contour. A good correlation was observed between SN-10 and psychoacoustic thresholds at 1 kHz, the only exception being the group of subjects with ascending audiogram, in which SN-10 overestimated the hearing threshold.

Acoustic Stimulation↗
PubMed1976

Acupuncture effect on neurosensory deafness.

Bilateral neurosensory deafness offers a unique opportunity to study the effects of acupuncture objectively. By treating only one ear, and using audiometric evaluation techniques instead of subjective evaluations of hearing, an analysis of any achieved improvement seemed feasible. Only patients with well documented bilateral nerve deafness were accepted into the program. A baseline audiogram with speech discrimination and puretone air and bone conduction thresholds was obtained prior to treatment. Thirty-eight patients underwent ten consecutive acupuncture treatments on one ear only, with the other ear serving as a control. After the course of acupuncture, the audiometrics were repeated by the same audiologist. There was no significant increase in hearing after acupuncture therapy.

Acupuncture Therapy↗
PubMed2000

Hearing function in a hyperbaric environment.

Navy divers' hearing function was assessed as part of three saturation deep dives to 1,000 feet of sea water (fsw) to determine explanations for threshold shifts observed under hyperbaric conditions. Across the three deep dives, different aspects of the ear were evaluated, including air- and bone-conduction pure-tone thresholds, real ear probe microphone measurements, auditory evoked potentials, and central auditory processing assessments. Attempts to measure middle ear function and cochlear function (through otoacoustic emissions) were unsuccessful. Baseline measurements were obtained at 0 fsw in air before and after the saturation deep dives. Results showed that some aspects of hearing function remained unchanged with increases in depth. In general, audiometric thresholds at depth were similar to those measured on the surface at 500, 1,000, 2,000, 3,000, and 4,000 Hz. However, hearing sensitivity actually improved at depth at 6,000 and 8,000 Hz. The use of a specially designed sound booth for a pressurized heliox environment yielded significantly lower ambient noise levels and improved the accuracy of threshold measurement. Auditory evoked potential measurements and central auditory processing function were relatively unaffected by changes in depth. Significant changes at depth were seen in ear canal resonance which shifted up in frequency; this finding was attributed to the effect of helium on the hearing mechanism. Because objective measurement of middle ear and inner ear function were not methodologically possible, questions still remain regarding the interpretation of middle and inner ear function at depth. Nonetheless, our overall findings suggest that most aspects of hearing functioning are similar under high atmospheric pressures and in heliox as they are on the surface, with the exception of shifts in ear canal resonance and improvements in audiometric thresholds at high frequencies.

Acoustic Impedance Tests↗
PubMed1999

[Combined use of rhBMP2/BCB and free periosteum in repairing segmental defects in radii of rabbits].

OBJECTIVE: To study the efficacy of combined use of rhBMP2/BCBand free periosteal graft in repairing segmental bony defects. METHODS: A new grafting material (rhBMP2/BCB) was made by combining recombinant human BMP2 (rhBMP2) and an antigen-free bovine cancellous bone (BCB) as a carrier. rhBMP2/BCB was used alone in conjunction with free periosteal graft to repair a 1.5 cm defect in the radius of the rabbit. The defect-repairing capability for each of the treatment modalities was assessed radiographically, biomechanically, and by densitometry and histological studies. RESULTS: rhBMP2/BCB used alone was capable of healing the defect in large by 16 weeks, with a similar repair process and mechanism seen with RBX. Combined use of rhBMP2/BCB and free periosteal graft was superior in terms of increased amount and quality of the new bone formed at the early stage of the repair process (within 12 weeks) to rhBMP2/BCB used in isolation, with the defect basically healed by 12 weeks. CONCLUSIONS: Both methods are effective in repairing segmental bony defects, with rhBMP2/BCB used in conjunction with free periosteal graft being most preferred, considering the satisfactory osteogenesis, osteoconduction and osteoinduction.

Animals↗
PubMed2002

[Early complications of surgery for chronic suppurative otitis media].

OBJECTIVE: To explore early post-operative complications following surgery for chronic suppurative otitis media. METHOD: From Jan 1992 to July 2000, 291 cases of chronic suppurative otitis media have been treated in our department. 79 cases underwent myringoplasty, 82 cases tympanoplasty, 88 cases modified radical mastoidectomy and 42 cases radical mastoidectomy. RESULT: Facial nerve palsies occurred in 3 cases (1.03%), bone conduction threshold elevation occurred in 13 cases (4.47%), wound infection occurred in 11 cases (3.78%), 7 patients (2.41%) reported symptoms related with chorda tympani trauma, symptoms of jaw discomfort were reported by 7 patients (2.41%) and imbalance or vertigo by 13 patients(4.47%). CONCLUSION: The incidence of early complications of surgery for chronic suppurative otitis media in this report was similar to previous reports.

Adolescent↗
PubMed2001

[The monaural pseudo-stereophonic hearing aid (BAHA) in unilateral total deafness: a study of 29 patients].

For many years, unilateral total deafness has been considered a minor handicap which does not require the fitting of a hearing aid. If the condition did give a major problem, the usual recommendation for this type of hearing loss was a CROS system which, in addition to problems of function and aesthetics, gave poor results. Faced with increasing demands from these patients, and given the good performance of bone conduction implants (BAHA), we decided to try to implant these devices on the deaf side, which allowed, by way of transcranial conduction, stimulation of the functioning ear and the re-establishment of a certain degree of stereophonic hearing. This study of 29 patients who were tested by stereophonic audiometry pre- and post-implantation shows that this type of aiding is beneficial, with improvement of the threshold of intelligibility against background noise of between 5 and 15 dB during Hirsch's test, correction of the "dead angle" on the deaf side, and improvement in localisation of sound in space. From the functional point of view, 88% of patients were satisfied with their aid, which they wore for 8 or 9 hours per day, and had a marked improvement in their hearing performance under various conditions which had proved very difficult for them before they were fitted with the aid. These results all demonstrate the effectiveness of the implant used in this way. The fact that sounds are received on the totally deaf side goes a long way towards establishing satisfactory hearing. True stereophonic hearing could not be established in any of the cases, because this requires input from two ears. It is for this reason that we have termed this type of aid as monaural pseudo-stereophonic.

Acoustic Stimulation↗
PubMed2002

[A case of cortical deafness following bilateral putaminal hemorrhage].

A 59-year-old man had suffered from consciousness disturbance and right hemiplegia in December, 1996. He was diagnosed as left putaminal hemorrhage and his symptoms improved by conservative treatment. After one week since the onset, when he became alert, he noticed deafness. He was admitted in our hospital because of deafness and dysarthria in March, 2001. T 1-weighted MR image of the brain revealed bilateral putaminal hemorrhage and a low signal area in the white matter of right temporal lobe. Single photon emission computed tomography image revealed hypoperfusion in the bilateral temporal lobes. His electrocochleogram and auditory brainstem response were normal. Audiogram revealed increased air and bone conduction thresholds. Therefore, we diagnosed his condition as cortical deafness. He could only recognize loudness as the sound by the electrical promontory test. These results indicate that his cortical deafness might be caused by his bilateral acoustic radiation damage associated with the right partial temporal lobe damage and that some fibers of the acoustic radiation, which were responsible for the recognition of loudness of sound, were spared. Therefore he has a possibility of regaining hearing capability by a cochlear implant.

Brain↗
PubMed2002

Hearing preservation in patients with labyrinthine fistulae.

INTRODUCTION: Labyrinthine fistula is the most common complication of chronic middle ear disease with cholesteatoma. We present a series of cases of labyrinthine fistula found during the surgical procedures carried out for cholesteatoma in a district hospital setting, over 11-year period. MATERIALS AND METHODS: This is retrospective study based on case notes and author's database for the period of 1987 to 1999. During this period 382 operations were performed and 25 (6.54%) patients found to have labyrinthine fistulae. We looked at the incidence, clinical presentation, surgical technique and hearing outcomes. A standard fistula classification system has been used in order to compare the pre and post-operative hearing. RESULTS: Records were available in 22 cases, which were 12 men, and 10 women with mean age of 45.2 years at presentation. Only one-third had presented with vertigo. Lateral semicircular canal was the most affected site (95%). Fistulae classified as types: I = 8 (36.3%), II-a = 1 (4.5%), II-b = 5 (22.9%) and III = 8 (36.3%). All patients had a standard open technique mastoidectomy. In 5 ears the hearing was lost pre-operatively (1 type II-b and 4 type III fistulae), and in remaining 17 the bone conduction thresholds remained unchanged in 15 (88 per cent) ears. Two dead ears directly related to the surgery and both were of type III fistula. CONCLUSIONS: One-staged mastoid surgery can be the treatment of choice in these cases. Meticulous surgical technique with adequate sealing of the fistula helps to preserve the hearing. An appropriate classification system is an essential tool in presentation and comparison of results.

Adult↗
PubMed2001

[The application of mastoid cavity plombage in open method tympanoplasty].

OBJECTIVE: The role mastoid cavity plombage played in restoring physiological function of external meatus in open method tympanoplasty was studied. METHOD: 85 cases of cholesteatoma otitis media were performed open method tympanoplasty with the broken bits of their own mastoid process cortex, homological costal cartilage or U shape periosteum connective tissue valve. And plombage was performed at the same time. The reconstruction of ossicular chain (type 0 tympanoplasty): 10 ears did not undergo reconstruction due to increase ment of bone conduction threshold or were in preparation for the second phase operation; 40 ears underwent type III tympanoplasty; 35 ears underwent type IV tympanoplasty. RESULT: The total improvement rate of hearing was 76%, among which 80% were performed type III tympanoplasty and 71.4% underwent type IV tympanoplasty. After operation, the time waited till dry-ears was 19.8 +/- 65.31 days and the dry-ears rate was 97.6% (83/85). Six months after operation, 89.4% (76/85) had smooth external meatus and fine self-cleaning function and no recurrence was found. CONCLUSION: As to cholesteatoma otitis media that could not be performed closed method tympanoplasty, U shape periosteum connective tissue valve and mastoid process cortex were used. Mastoid cavity plombage with homological costal cartilage could effectively overcome the shortcomings of destruction of physiological structure of external meatus caused by open method tympanoplasty, the self-cleaning function of skins of external meatus was remained and the life quality of patients after operation was increased.

Adolescent↗
PubMed2001

[The clinical characteristics of adhesive type cholesteatoma].

OBJECTIVE: To study the clinical characteristics of adhesive type cholesteatoma. METHODS: Fifty-two cases (52 ears) of adhesive type cholesteatomas were reviewed. Of the 52 cases there were 30 males and 22 females; 24 left ears and 28 right ears. The age of the patients ranged from 8 to 70 years. All of the patients were treated by tympanoplasty, and the open and close methods were performed in 37 ears and 10 ears, respectively. Other methods were employed in the remaining 5 cases. Nine ears underwent tympanoplasty type "O" without ossicular re-construction for an increase in the threshold of the bone conduction. Types I, III and IV tympanoplasties were performed in 1, 16 and 26 ears, respectively. RESULTS: The structures of the upper parts of the stapes had disappeared in 25 ears, which was significantly higher in this series than that in the attic type cholesteatoma. The over-all recovery rate of hearing was 69.8%, while 75.9% and 55.6% in the open and closed tympanoplasties, respectively. Postoperative complications of perforations and re-adhesions of the tense part of the tympanic membrane were observed in 3 and 4 ears, respectively. CONCLUSIONS: Adhesive type cholesteatoma is not uncommon. The cause of this disease may be the functional defects in the pharynotympanic tube. A thorough and effective treatment for the secretory otitis media is crucial for the prevention of adhesive type cholesteatomas. The open method tympanoplasty was considered as the first choice for adhesive type cholesteatoma while the closed method must be great careful.

Adolescent↗