| 11. |
- Rahman, Anisur, et al.
(författare)
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Structural and functional properties of the healed tympanic membrane : a long-term follow-up after laser myringotomy
- 2007
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Ingår i: Otology and Neurotology. - 1531-7129 .- 1537-4505. ; 28:5, s. 685-691
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Tidskriftsartikel (refereegranskat)abstract
- Hypothesis: The short-term healing scar that forms after experimental laser myringotomy will revert to a normal lamina propria in the long run. The mechanical stiffness will stay normal. Background: Recent studies have shown severe structural changes in the fibrous layer in the early course after experimental laser myringotomy, whereas the scar quickly restored the strength of the tympanic membrane (TM). A reorganization of the fiber layer is expected to occur. Methods: Potassium titanyl phosphate laser myringotomy was made on one side of the TM in Sprague-Dawley rats. The ear of the other side was untouched and used for control. After half a year of observation, the stiffness and strength of the healed TMs were measured with moiré interferometry and examined with otomicroscopy and light and electron microscopy. Results: The interferometry readings showed a slightly reduced strength in the myringotomized and healed TMs. After half a year, still there were immense structural changes including increased thickness over a wide area of the pars tensa with increased amounts of fibers. An obvious reorganization of the fiber layer was lacking. Conclusion: Laser myringotomy causes profound, long-standing, or permanent structural changes in the lamina propria of the pars tensa, whereas the strength of the TM may become slightly reduced.
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| 12. |
- Stenfelt, Stefan, et al.
(författare)
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Bone-conducted sound: Physiological and clinical aspects
- 2005
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Ingår i: Otology and Neurotology. - : Lippincott Williams and Wilkins. - 1531-7129 .- 1537-4505. ; 26:6, s. 1245-1261
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Forskningsöversikt (refereegranskat)abstract
- Objective: The fact that vibration of the skull causes a hearing sensation has been known since the 19th century. This mode of hearing was termed hearing by bone conduction. Although there has been more than a century of research on hearing by bone conduction, its physiology is not completely understood. Lately, new insights into the physiology of hearing by bone conduction have been reported. Knowledge of the physiology, clinical aspects, and limitations of bone conduction sound is important for clinicians dealing with hearing loss and is the purpose of this review. Data Sources: The data were compiled from the published literature in the areas of clinical bone conduction hearing, bone conduction hearing aids, basic research on bone conduction physiology, and recent research on bone conduction hearing from our laboratory. Conclusion: Five factors contributing to bone conduction hearing have been identified: 1) sound radiated into the external ear canal, 2) middle ear ossicle inertia, 3) inertia of the cochlear fluids, 4) compression of the cochlear walls, and 5) pressure transmission from the cerebrospinal fluid. Of these five, inertia of the cochlear fluid seems most important. E-one conduction sound is believed to reflect the true cochlear function; however, certain conditions such as middle ear diseases can affect bone conduction sensitivity, but less than for air conduction. The bone conduction route can also be used for hearing aids; since the bone conduction route is less efficient than the air conduction route, bone conduction hearing aids are primarily used for hearing losses where, air conduction hearing aids are contraindicated.
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| 13. |
- Thomsen, J., et al.
(författare)
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Local overpressure treatment reduces vestibular symptoms in patients with Ménière's disease : A clinical, randomized, multicenter, double-blind, placebo-controlled study
- 2005
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Ingår i: Otology and Neurotology. - : Ovid Technologies (Wolters Kluwer Health). - 1531-7129 .- 1537-4505. ; 26:1, s. 68-73
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: To evaluate the efficacy of a new device, the Meniett, in the treatment of Ménière's disease. The device delivers pressure pulses to the middle ear through a ventilating tube in the tympanic membrane at a frequency of 6 Hz for 0.6 second. After rising to a pressure level of 1.2 kPa, the pressure oscillates between 0.4 and 1.2 kPa. It is believed that the pressure changes are conveyed to the inner ear, inducing a transport of fluids via the pressure outlets and thus reducing the endolymphatic hydrops. Study Design: A clinical, randomized, multicenter, double-blind, placebo-controlled study. A total of 40 patients were included that had active Méniè re's disease according to American Academy of Otolaryngology-Head and Neck Surgery criteria, aged between 20 and 65 years, with a history of at least eight attacks during the past year. After insertion of the ventilation tube, the patients should have had attacks of vertigo for 2 months before entering the study. Outcome Measures: Primary study endpoints were change in frequency of vertigo, change of functionality profile, and change in patient perception of vertigo (visual analogue scale), secondary endpoints were perception of tinnitus, aural pressure, and hearing, as well as an audiologic evaluation of hearing before and after the treatment period. Results: The functionality level improved statistically significantly in the active group compared with the placebo group (p = 0.0014), as did the visual analogue scale evaluation of vertigo (p = 0.005). There was a trend toward a reduction of the frequency of vertiginous attacks that was not significant (p = 0.090). With regard to the secondary endpoints, there was no statistical difference between active and placebo groups. Conclusion: Local overpressure treatment is a novel treatment that is noninvasive, nondestructive, and safe. It significantly reduces vestibular symptoms in patients with Ménière's disease. The Meniett was cleared by the Food and Drug Administration in 2000.
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| 14. |
- Van Eyken, Els, et al.
(författare)
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The Contribution of GJB2 (Connexin 26) 35delG to Age-Related Hearing Impairment and Noise-Induced Hearing Loss
- 2007
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Ingår i: Otology and Neurotology. - : Lippincott Williams & Wilkins. - 1531-7129 .- 1537-4505. ; 28:7, s. 970-975
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Tidskriftsartikel (refereegranskat)abstract
- Hypothesis: The common GJB2 (Connexin 26) 35delG mutation might contribute to the development of age-related hearing impairment (ARHI) and noise-induced hearing loss (NIHL).Background: GJB2, a gene encoding a gap junction protein expressed in the inner ear, has been suggested to be involved in the potassium recycling pathway in the cochlea. GJB2 mutations account for a large number of individuals with nonsyndromic recessive hearing loss, with 35delG being the most frequent mutation in populations of European origin. Other genes involved in potassium homeostasis have been suggested to be associated with ARHI and NIHL, and distortion product otoacoustic emission distortions indicative of hearing loss alterations have been found in 35delG carriers.Method: We genotyped 35delG in two distinct sample sets: an ARHI sample set, composed of 2,311 Caucasian samples from nine different centers originating from seven different countries with an age range between 53 and 67 years, and an NIHL sample set consisting of 702 samples from the two extremes of a noise-exposed Polish sample.Results: After statistical analysis, we were unable to detect an association between 35delG and ARHI, nor between 35delG and NIHL.Conclusion: Our findings indicate that there is no increased susceptibility in 35delG carriers for the development of ARHI or NIHL.
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| 15. |
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| 16. |
- Brantberg, K, et al.
(författare)
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Posterior canal dehiscence syndrome caused by an apex cholesteatoma
- 2006
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Ingår i: Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology. - : Ovid Technologies (Wolters Kluwer Health). - 1531-7129. ; 27:4, s. 531-534
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Tidskriftsartikel (refereegranskat)
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| 17. |
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| 18. |
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| 19. |
- Larsson, C, et al.
(författare)
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Pars flaccida displacement pattern in otitis media with effusion in the gerbil
- 2005
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Ingår i: Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology. - : Ovid Technologies (Wolters Kluwer Health). - 1531-7129. ; 26:3, s. 337-343
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Tidskriftsartikel (refereegranskat)
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| 20. |
- Majdalawieh, Osama F, et al.
(författare)
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Linearity and Lever Ratio of the Normal and Reconstructed Cadaveric Human Middle Ear
- 2008
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Ingår i: Otology & Neurotology. - 1531-7129. ; 29:6, s. 796-802
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Tidskriftsartikel (refereegranskat)abstract
- Hypothesis: The linearity and the level ratio are different in reconstructed ears. Background: The linearity of the reconstructed human middle ear (ME) has not been previously explored. It is important to analyze if high sound pressure levels (SPLs) result in distortion due to nonlinearities particularly because hearing aids have high-output SPLs. The diseased ME is reconstructed with prostheses. These diseased ears frequently need additional amplification with hearing aids, and it is unclear if reconstruction itself leads to nonlinear ME responses. Methods: Eight fresh human cadaveric temporal bones were used. Pure tones of 70, 90, and 110 dB SPL at 500, 1,000, and 3,000 Hz were presented to the ear canal. Umbo and stapes displacements were measured by means of a laser Doppler vibrometer. After removing the incus, the tympanic membrane assembly to the stapes head prosthesis was placed, and measurements were repeated. Results: Stapes footplate vibrations in the reconstructed ears are 10 to 15 dB lower than those of the normal ears. In both normal and reconstructed ears, the footplate vibrations are linearly related to SPL at the tympanic membrane between 70 and 110 dB SPL at the frequencies tested. For the lever ratio, intact ears are more efficient at transmission of umbo vibrations to the stapes compared with reconstructed ears. Conclusion: To within acceptable limits, the ME seems to be linear between 70 and 110 dB SPL input levels, across the speech frequencies, and this does not change with reconstruction. The reconstructed human ME seems to have a less efficient lever ratio than the intact ME.
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