Combined effect of fluid and pressure on middle ear function.
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In our previous studies, the effects of effusion and pressure on sound transmission were investigated separately. The aim of this study is to investigate the combined effect of fluid and pressure on middle ear function. An otitis media with effusion model was created by injecting saline solution and air pressure simultaneously into the middle ear of human temporal bones. Tympanic membrane displacement in response to 90 dB SPL sound input was measured by a laser vibrometer and the compliance of the middle ear was measured by a tympanometer. The movement of the tympanic membrane at the umbo was reduced up to 17 dB by the combination of fluid and pressure in the middle ear over the auditory frequency range. The fluid and pressure effects on the umbo movement in the fluid-pressure combination are not additive. The combined effect of fluid and pressure on the umbo movement is different compared with that of only fluid or pressure change in the middle ear. Negative pressure in fluid-pressure combination had more effect on middle ear function than positive pressure. Tympanometry can detect the middle ear pressure of the fluid-pressure combination. This study provides quantitative information for analysis of the combined effect of fluid and pressure on tympanic membrane movement. (+info)
The comparison of single-dose ceftriaxone, five-day azithromycin, and ten-day amoxicillin/clavulanate for the treatment of children with acute otitis media.
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The aim of the study was to evaluate the efficacy of short-course antimicrobial therapies [single intramuscular dose of ceftriaxone (50 mg/kg, not exceeding 1 g), 5 days of azithromycin (10 mg/kg on day 1, then 5 mg/kg daily on days 2-5) and the traditional 10-day course of amoxicillin/clavulanate (90/6.4 mg/kg/day in 2 doses)] in children with acute otitis media (AOM). The study was conducted as a prospective, comparative, open randomized trial between February 2001 and April 2003, and 104 children were enrolled, with a mean age of 3.8 (2.3) years. The clinical and otoscopic assessments of the children were made on days 0, 3, 11 and 30 after admission, and tympanometry was performed on day 30. The patients were diagnosed and followed with a scoring system. Clinical success was achieved in 29/34 patients (85.3%) in the ceftriaxone group, 27/31 patients (87.1%) in the azithromycin group and 34/39 children (87.2%) in the amoxicillin/clavulanate group. The rate of persistence of middle-ear fluid did not differ between the three groups (p>0.05). During the one-month period, no recurrent case was observed. The most common drug-related adverse effects were associated with the gastrointestinal system. In conclusion, for the treatment of children with AOM, the clinical success of single-dose intramuscular ceftriaxone and of five-day azithromycin treatments was comparable to that of the traditional 10-day therapy with high-dose amoxicillin/clavulanate. (+info)
Comparative study between school performance on first grade children and suppression of otoacoustic transient emission.
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School learning can be hampered if there are defects on the central auditory process. Since those with auditory deficiency can be rehabilitated, it is fundamental that we identify them. Otoacoustic emissions test has low cost and operational ease. STUDY DESIGN: clinical and experimental. AIM: to study the relationship between school learning and transient otoacoustic emission suppression by contralateral stimuli. MATERIAL AND METHODS: 39 individuals, from 7 to 12 years of age were evaluated, 19 (48.7%) with good school performance and 20 (51.3%) poor performers. RESULTS: A transient otoacoustic emission suppression failure for contralateral acoustic stimuli was more frequently found among children with poor school performance. We established a value of 1.6 dB SPL for emission reduction that characterized those children as belonging to the poor learning performance group: sensitivity 65%, specificity 72,2%, accuracy of 68.4%, positive predictive value of 72.2%. CONCLUSION: The contralateral emission suppression test of the right ear can be predictive of school difficulties in individuals from six to twelve years of age. (+info)
Simultaneous measurements of ossicular velocity and intracochlear pressure leading to the cochlear input impedance in gerbil.
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Auditory disorders and acquisition of the ability to localize sound in children born to HIV-positive mothers.
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The objective of the present study was to evaluate children born to HIV-infected mothers and to determine whether such children present auditory disorders or poor acquisition of the ability to localize sound. The population studied included 143 children (82 males and 61 females), ranging in age from one month to 30 months. The children were divided into three groups according to the classification system devised in 1994 by the Centers for Disease Control and Prevention: infected; seroreverted; and exposed. The children were then submitted to audiological evaluation, including behavioral audiometry, visual reinforcement audiometry and measurement of acoustic immittance. Statistical analysis showed that the incidence of auditory disorders was significantly higher in the infected group. In the seroreverted and exposed groups, there was a marked absence of auditory disorders. In the infected group as a whole, the findings were suggestive of central auditory disorders. Evolution of the ability to localize sound was found to be poorer among the children in the infected group than among those in the seroreverted and exposed groups. (+info)
Effects of deafening and cochlear implantation procedures on postimplantation psychophysical electrical detection thresholds.
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