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At least 1,243 records · Page 69Linked to original sources
PubMed2003

Retrospective case study of carbon dioxide laser stapedotomy with lens-based and mirror-based micromanipulators.

Most clinical studies on carbon dioxide (CO2) (lambda = 10.6 mm) laser stapedotomy have been carried out with the laser guided by a conventional lens-based micromanipulator, with the attendant risks of correct aiming (HeNe) and surgical (CO2) beam misalignment. Hence, engineering advances have attempted to improve laser targeting as well as the spot size focus. The development of the mirror-based micromanipulator was a response to this need but no data concerning its use in stapes surgery is available. We performed a retrospective case-series review of patients treated for otosclerosis between 1992 and 2000. Primary laser stapedotomy was performed in 218 consecutive patients. In the first 78 procedures, the aiming beam (HeNe, lambda = 632 nm) and surgical beam (CO2) were guided with a conventional lens-based micromanipulator whereas in the subsequent 140 procedures, they were guided by using a mirror-based micromanipulator. Hearing was tested at six and 12 months. The mean (SD) airbone gap was 5 dB (4.5) and 4.5 dB (3.9). The mean closure was 15 dB (9.9) and 14.4 dB (9.4). The mean change in the high-tone bone-conduction level was 5.5 dB (7.3) and 7.8 dB (7.5). Overheating of the facial canal produced transient facial paralysis in one case and was due to misalignment of the beams with the lens-based micromanipulator. Use of the mirror-based micromanipulator obviated the need to verify alignment. The light-weight and superior optical yield of this system made it possible to reduce the number of impacts on the footplate by the integral restitution of the energy source. This study demonstrated that the CO2 laser is an effective method for performing stapedotomy. In addition, microtrauma to the labyrinth is reduced by its ability to perform calibrated footplate fenestration without mechanical or vibrational injury to the inner ear. The optical reflection micromanipulator simplified beam alignment and enhanced surgical comfort.

Adolescent↗
PubMed1976

Pre and post-glycerol special audiometric tests battery results in endolymphatic hydrops.

The glycerol test for endolymphatic hydrops was administered to 17 patients exhibiting classical symptoms of Meniere's disease. A complete battery of audiometric tests including the SISI, TTD (Rosenberg variation). ABLB, Sweep Frequency Bekesy, two tests of speech discrimination (Rush Hughes and Northwestern), and air and bone conduction thresholds were administered pre and post-glycerol ingestion in order to determine the effect of osmotic diuresis. Improvement in pure-tone sensitivity and speech discrimination scores were most often observed. Among the special audiometric tests only the SISI scores exhibited changes, however, these could be related to the threshold changes. There were no significant differences observed in the threshold tone decay tests nor in the ABLB. The sweep frequency Bekesy test revealed only the changes which were observed in pure-tone sensitivity.

Acoustic Stimulation↗
PubMed1984

Stapedectomy in residency training.

The number of new patients with otosclerosis seen by the average otolaryngologist has declined over the past several years. As a result, a controversy has arisen regarding the ability to train residents adequately in the technique of stapedectomy. In this regard, we have analyzed 44 consecutive stapedectomies performed by senior residents, under direct faculty supervision, at the University of California, San Francisco. All procedures were total stapedectomies, performed under local anesthesia, utilizing either wire-vein or wire-perichondrium technique. Four of the ears required footplate or promontory drilling. Closure to within 10 dB of the preoperative bone conduction, averaged over the speech frequencies of 500, 1000, and 2000 Hz, was achieved in 75% of ears, and closure to within 20 dB in 93% of ears. In no patient was hearing made worse. While there were no permanent complications, self-limited problems occurred in 9% of the procedures. Despite a declining caseload of otosclerotic ears in residency programs, it is possible to train residents safely in stapes surgery, given a program of consistent technique and close faculty supervision.

Adult↗
PubMed2004

Treatment of idiopathic hyperphosphatasia with intensive bisphosphonate therapy.

UNLABELLED: In a family with IH, a rare high turnover bone disease, two older siblings were wheelchair-bound with severe skeletal deformity by age 15. Their youngest affected sibling was treated intensively with intravenous bisphosphonates for 3 years. The treatment was well tolerated and prevented the development of deformity and disability. INTRODUCTION: Idiopathic hyperphosphatasia (IH, also known as juvenile Paget's disease) is a rare genetic bone disease characterized by very high bone turnover and progressive bony deformity. Inhibitors of bone resorption have been used to suppress bone turnover in the short term, but there is no published data on long-term efficacy. MATERIALS AND METHODS: An 11-year-old girl with IH, who had two severely affected older siblings, presented with progressive deformity and deafness and long bone fractures. Conventional pediatric doses of pamidronate had failed to prevent clinical deterioration or suppress bone turnover completely. Intensive bisphosphonate therapy (frequent 5-mg ibandronate infusions) was given to try and arrest progression of the skeletal disease. Growth and development, pure tone audiometry, biochemistry, radiology, densitometry (DXA), and bone histology were monitored. RESULTS: A total of 45 mg ibandronate was given over 3 years until skeletal maturity was reached (20, 15, and 10 mg for years 1-3, respectively). Ibandronate treatment was well tolerated, and biochemical markers of bone turnover suppressed to within the age-appropriate normal range There was some progression of her thoracic kyphosis, but she had no further fractures and remained mobile and active at an age when her siblings had become wheelchair-bound. A significant recovery of hearing (p < 0.01) was documented, particularly at low frequencies. Radiographs showed improvement in spinal osteoporosis and cortical bone dimensions and arrest of progressive acetabular protrusion. Areal bone density increased substantially (lumbar spine z-score from -2.2 to + 1.8). Tetracycline-labeled bone biopsy specimens were taken before and after 18 months of intensive treatment. The second biopsy showed suppression of bone turnover and a doubling of trabecular thickness, with no mineralization defect, and no osteopetrosis. CONCLUSIONS: Intensive bisphosphonate treatment prevented the development of deformity and disability and improved hearing in this child with IH. The dose of bisphosphonate, which is substantially greater than is usually used in pediatric bone disease, had no adverse effects, in particular on bone mineralization.

Alkaline Phosphatase↗
PubMed2003

A benefit-risk assessment of ofloxacin otic solution in ear infection.

Ofloxacin is a fluoroquinolone antibacterial with potent bactericidal activities and the topical otological preparation of this drug has been clinically utilised since the late 1980s. The rate of eradication with ofloxacin ranges from 83.3% to 100% for all pathogens commonly isolated from middle ear effusions in cases of otitis media and otitis externa. Despite the significant length of its usage, emergence of resistant pathogens has been rarely encountered in clinical trials; only two strains of Pseudomonas aeruginosa have been documented with decreased susceptibility to ofloxacin following the use of the otic solution.Ear infections, including otitis externa, chronic suppurative otitis media and otorrhoea associated with tympanostomy tubes, are common problems in clinical practice. The potential complications associated with ear infection can be otological, extratemporal, or even psychosocial. They are sometimes fatal and the effect can be long-lasting and detrimental. The use of an effective topical antibacterial with high cost-effectiveness is definitely warranted. As regards various clinical aspects, including overall success rate, symptomatic relief of otalgia and otorrhoea, ofloxacin otic solution was found to be more effective than comparator agents, be it a topical antibacterial, a systemic antibacterial or combination drugs. The systemic absorption of fluoroquinolones is minimal after topical application. Ofloxacin otic solution 0.3% has been shown to have a low rate of adverse drug reactions. Adverse reactions to ofloxacin otic solution were generally mild. The lack of ototoxic effect from ofloxacin eardrops, even in the concentration higher than 0.3%, has been demonstrated in animal studies. In the clinical setting, no increase in bone-conduction threshold has been shown after the treatment of topical ofloxacin otic solution. There have not been any reports of ototoxicity with ofloxacin otic solution since its approval. To conclude, ofloxacin otic solution 0.3% is clinically effective in the treatment of otitis externa and chronic suppurative otitis media in particular with respect to the overall cure rate, relief of otalgia and otorrhoea. It is well tolerated, with minimal adverse effects. It is not associated with any ototoxicity both experimentally and clinically.

Administration, Topical↗
PubMedDate not supplied

Variables affecting the drill-generated noise levels in ear surgery.

The manner in which the variables rotation speed, type of burr, burr size and site of drilling influence bone-conducted, drill-generated noise levels in ear surgery, has been investigated. From the results obtained, the following conclusions can be drawn. 1. The noise levels were primarily influenced by the size of the burr. The 6 mm cutting burrs gave a noise level of 88-108 dB, the use of a 4 mm one resulted in a reduction of 1-6 dB and the use of a 2 mm one, 5-16 dB. The mean noise levels of the diamond burrs were 5-11 dB lower than the mean noise levels of the cutting ones. 2. Variations in rotation speed had only a slight influence on the noise levels produced (0-5 dB). 3. Three different types of cutting burr were tested. All gave noise levels of about the same order of magnitude. 4. The noise levels around the cochlea were only slightly influenced by the localization of the drilling within the ear (less than 1.8 dB). 5. Drill-induced noise levels in ear surgery cannot be reduced to any great extent. Possible noise traumas to the inner ear can only be avoided by minimizing the duration of drilling and thus, the duration of harmful noise exposure to the cochlea.

Ear↗
PubMedDate not supplied

Influence of altered middle ear pressure on cochlear microphonics.

Patients with otitis media with effusion often have impaired hearing loss caused by bone conduction. Among several possible causes for this hearing loss, the influence of middle ear pressure upon hearing was examined. Cochlear microphonics (CM) of guinea pigs were recorded under positive or negative pressure created simultaneously in the middle ear and in the external ear canal. CM was recorded from each turn (basal, second, third and apical). Whereas under negative pressure CM decreased suddenly but soon became stable, under positive pressure CM normalized gradually after the initial drop. Thus, in the stable state, CM amplitude was low under negative pressure but was slightly subnormal under positive pressure. One possible explanation is that perilymphatic efflux appears to cause such recovery of CM under positive pressure. it is postulated that perilymphatic inflow does not seem to occur under negative pressure, since CM and perilymphatic pressure were stable.

Animals↗
PubMed1993

Variability analysis of Fo parameter in the voice of individuals with hearing disturbances.

The material of this investigation comprised a group of 18 patients with deep hypoacousis (over 70 dB) or complete deafness which, depending on the onset of the deafness, was divided into the 3 categories: congenital, early childhood to 3rd year of life, and postlingual. All of them underwent ENT, phoniatric and stroboscopy examinations; in 10, X-ray tomography of the larynx was also performed. The status of hearing ability was assessed by audiometric examinations using pure tones in air and bone conductions. The acoustic examinations comprising spectrographic and tonographic analyses were performed on an appropriate linguistic material including vowels, isolated words, sentences and reading text. The measurement of Fo was performed on isolated vowels. In order to characterise the degree and kind of periodicity disturbances the following parameters were estimated: the medium value of fundamental frequency, the range of Fo variability, the maximal change of period length from cycle to cycle, and its medium value (jitter). The results of the acoustic examinations revealed different degrees and kinds of periodicity disturbances depending on the depth of the hypoacousis and its onset.

Adult↗
PubMed1995

An audiometric test battery for the evaluation of occupational exposure to industrial solvents.

Subjects exposed to various industrial solvents were evaluated with a test battery comprising both peripheral and central auditory tests. After otoscopy, all subjects underwent the following audiometric procedures: air- and bone-conduction in the conventional frequency range, air-conduction in the extended high-frequency range, speech recognition score, low-pass filtered speech recognition, stapedius reflex threshold, stapedius reflex decay, auditory brainstem response, and cognitive event-related responses. Apart from mild to moderate sensorineural hearing loss found in some of the subjects, the peripheral tests were normal in most subjects. The central tests (filtered speech and cognitive responses) showed varying degrees of abnormality which may reflect different levels of disease in this group of subjects.

Adult↗
PubMed1978

Modification and application of the computerized automatic audiometer.

Recently, medical information processing systems applying computers have achieved marked advances in parallel with the development of highly accurate automatic measuring instruments. The authors already in 1974 developed and reported a computerized automatic audiometer containing a micro-computer which stored a program for audiometric procedures. Subsequently the authors have developed a compact, multi-purpose audiometric instrument which executes the standard air-bone conduction audiometry, with the exclusion of masking, automatically with a built-in micro-computer. An outline of the instrument is as follows: 1. The instrument is composed of a memory, a control unit, programs for data processing and measurement, a character display for instructing subjects and an audiogram display. It can be operated manually in the same way as a conventional audiometer. 2. Test errors and any abnormally large differences between the responses of the two ears can be detected automatically, and the tests can then be re-executed manually after finishing the automatic procedure for correction of the data. 3. The instrument is provided with output terminals for connection to an external computer or other peripheral equipment. It is designed to be compact and light weight.

Adult↗
PubMed1989

Experience with percutaneous titanium implants in the head and neck: a clinical and histological study.

Percutaneous implants have been associated with numerous problems. However, by using skin-penetrating, bone-anchored titanium implants, developed by Professor Brånemark at the Department of Anatomy, University of Göteborg, good long-term results have been observed. These implants have been in clinical use for anchorage of bone-conducting hearing aids and facial prostheses since 1977 and 1979, respectively. The total number of implants is approximately 700. Less than 4% of the observations have shown significant irritation. Biopsies from 33 patients were collected for histological studies. In the irritated skin there was an increased number of inflammatory cells, mainly polymorphonuclear cells, B-cells, and plasma cells but not T-cells. This suggests a response directed against exogenous agents rather than an allergic reaction against the implant per se.

Ear, External↗
PubMed2004

Factors predicting severity of tinnitus: a population-based assessment.

The Blue Mountains Hearing Study (BMHS) has shown that tinnitus affects one in three older Australians with 16% of cases describing severe annoyance. Among persons describing severe symptoms, 52% have sought professional help. We aim to identify factors associated with the severity of tinnitus in 2,015 persons aged over 54 years. Comprehensive questionnaires about hearing were administered. Air- (250-8000 Hz) and bone-conduction (500-4000 Hz) audiometric thresholds of both ears, together with transient evoked and spontaneous otoacoustic emissions, were measured. Factors predicting severity of tinnitus were assessed in Cox proportional hazard models. After multivariate adjustment, factors significantly associated with severe tinnitus were hearing loss (relative risk [RR] 2.9), dizziness (RR 2.0), head injury (RR 2.0), sinus and middle ear infections (RR 1.9), and mastoiditis (RR 3.9). Associations with mild tinnitus included age (RR 0.8), hearing loss (RR 1.4) and history of dizziness (RR 1.5), meningitis (RR 2.2), and migraine (RR 1.5). Knowledge of these factors could contribute to improved tinnitus management.

Age Factors↗
PubMed2006

The status of diagnostic testing following referral from universal newborn hearing screening.

The Joint Committee on Infant Hearing 2000 position statement includes guidelines for the development of Early Hearing Detection and Intervention programs. These guidelines provide specific recommendations for the audiologic test battery for infants who fail a newborn infant hearing screening. The recommended test battery includes electrophysiologic measures such as the ABR, frequency specific electrophysiologic tests, bone-conducted ABR, OAEs, tympanometry using high frequency probe stimuli, and acoustic reflexes. In the Commonwealth of Kentucky, 42 centers are listed as providing follow-up diagnostic testing services for infants failing the newborn hearing screening. The purpose of this investigation was to determine how many of these centers were abiding by the Joint Committee guidelines. Results show that only three of 42 centers listed are providing services that meet the guidelines. Less than 50% of infants identified with hearing loss are referred for genetic evaluations by the audiologist. Only 19 of the 42 sites listed provide amplification services for infants identified with hearing loss.

Acoustic Impedance Tests↗
PubMed1999

[Clinical experiences and postoperative results with partially implantable middle ear implant].

A partially implantable middle ear implant using an ossicular vibrator of a piezoelectric ceramic bimorph has recently been developed in Japan as a new rehabilitative method for hearing. Four patients at the Miyazaki Medical College Hospital were implanted with this device between September 1994 and October 1996. Implantation of the internal component was performed under local anesthesia after confirmation of sufficient sensitivity to the ossicular vibrator in an intraoperative vibratory hearing test. All patients regained socially useful hearing with the middle ear implant without any foreign body reactions or recurrence of otitis media. None of the cases showed any elevations of bone conduction thresholds 2 to 4 years postoperatively. Natural and clear sounds without interference noise and howling due to acoustic feedback were highly satisfactory in all patients. However, the first case, who had an implant in an ear following cholesteatoma surgery using the intact canal wall technique, experienced about a 10dB deterioration of the average hearing level with the implant 2 years after implantation. Gradual deterioration appeared to be caused by the retracted tympanic membrane interfering with the mobility of the ossicular vibrator. The following three cases were implanted in ears previously operated on by radical mastoidectomy, showing stable or improving hearing results with the implant. Closure of the external canal skin at the cartilaginous portion at the time of implantation seemed appropriate to maintain a sufficient middle ear space for the ossicular vibrator to work properly. Our case study confirms that the partially implantable middle ear implant is a safe and useful tool for patients with mixed deafness which cannot be satisfactorily rehabilitated by tympanoplasty and/or a conventional hearing aid.

Deafness↗
PubMed2001

[Pathogenesis mechanism in ear fullness in otosclerosis].

To clarify the mechanism underlying ear fullness in otosclerosis, we studied the relationship between clinical features and examinations. Subjects were 116 otosclerosis patients (140 ears). The presence or absence of ear fullness was judged from a questionnaire in initial diagnosis or a chart description. Ear fullness was observed in 44 ears (31%) and absent in 96. The averaged air and bone conduction hearing levels (500 Hz-4 k Hz) in initial diagnosis were significantly lower in the group with ear fullness. The difference in averaged hearing was mainly apparent at 2 k Hz and 4 k Hz. The difference in hearing at lower frequencies (125 Hz, 250 Hz, and 500 Hz) and higher frequencies (2 k Hz, 4 k Hz, and 8 k Hz) was significantly larger in the group of ear fullness. From these results, we postulated that ear fullness in otosclerosis is caused by fixation of the stapes. The psychoacoustic abnormal sensation caused by lower input of lower-frequency sound or incomplete fixation of the stapes may cause ear fullness. Further study is needed to clarify the pathogenesis of ear fullness in different ear pathologies.

Adult↗
PubMed2000

[Physicochemical characterization and histological bone-formability evaluation of electrically polarized hydroxyapatite].

Acceleration and deceleration of bone-like crystal growth on electrically polarized hydroxyapatite ceramics are induced by their surface changes, as recently reported by Yamashita, et al. In this study, new-bone-forming ability of electrically polarized hydroxyapatite was physicochemically characterized and histologically evaluated using femora and tibiae of rabbits. The electrical polarizability of hydroxyapatite was demonstrated by thermally stimulated current measurements. No significant difference between polarized and non-polarized hydroxyapatite was recognized by IR spectroscopy and X-ray diffractometry. A negatively charged hydroxyapatite surface exhibited osteogenesis with direct bone contacting in early stage. A positively charged surface resulted in a small amount of bone formation on the surface. On the contrary, in the zone isolated by fibrous layer, a large volume of bone newly formed. It is useful that the outstanding bone-formability in the early stage on a negatively charged surface implies more rigid initial fixation in orthopedic and dental fields. Positively charged surfaces have a new-bone-conducting property that acts over a long distance, and the possibility of controlling osteogenesis.

Animals↗