Click-evoked otoacoustic emissions and the influence of high-frequency hearing losses in humans.

Click-evoked otoacoustic emissions (cEOAEs) are thought to reflect the presence of highly tuned mechanisms involved in sound processing inside the cochlea. When the sensitivity and tuning of the inner ear are impaired in some frequency range, the spectral components of cEOAEs in the same frequency range are expected to be altered if the previous premise is correct. Although clinical experience does not contradict such an interpretation, fundamental aspects of cEOAE generation and propagation in the cochlea are not clear enough to preclude possible additional influences of remote cochlear places on cEOAE. In order to analyze this possibility, ultra-high-frequency hearing thresholds between 8 and 16 kHz were assessed in 43 human subjects that had clinically normal hearing thresholds in the frequency range of cEOAEs. The magnitude of their cEOAEs was found to be correlated to their average ultra-high-frequency hearing threshold, especially when ears presenting spontaneous otoacoustic emissions were not taken into account (p = 0.002, r2 = 0.29). Age and ultra-high-frequency hearing thresholds were correlated (p < 0.01, r2 = 0.40); thus it is not possible to exclude that aging was the primary cause of the observed trend. The contribution of ultra-high-frequency hearing status to cEOAE magnitude, perhaps in relation to age, seems to explain a significant part of the variance of "normative" emission data and may be of interest for early detection of high-frequency hearing impairments.

Transient-evoked otoacoustic emissions and high-frequency acoustic trauma in the guinea pig.

Transient-evoked otoacoustic emissions (TEOE) disappear when hearing loss exceeds 40 dB in the range 1-4 kHz, due to impairment of cochlear outer hair cells. Early screening of sensorineural hearing losses is based on this finding. However, little is known as to the frequency specificity of TEOE abnormalities in a damaged cochlea. TEOE were recorded in 18 normally hearing guinea pigs in a range from 1.5 to 5 kHz before and after exposure to loud pure tones (3-10 kHz, 95-105 dB SPL, 1-10 min). The thresholds of eighth-nerve compound action potentials (CAP) were monitored with a round-window electrode; it was confirmed that acoustic overexposure resulted in typical high-frequency threshold elevations (10 to 50 dB). Most TEOE components were found at lower frequencies at which CAP thresholds did not change. However, a significant linear regression was found between their amplitudes and the percentage of basal cochlea with unaltered CAP thresholds (r = 0.69, p < 0.0001). Two alternative hypotheses are proposed to account for this correlation. Either acoustic trauma induced some minute cochlear damage at places tuned to low frequencies and TEOE were more sensitive to it than CAP thresholds, or significant contributions to lower-frequency TEOE came from the most damaged cochlear places tuned to much higher frequencies.

Auditory threshold evaluation by distortion-product oto-acoustic emissions using decision support system.

Distortion-product oto-acoustic emissions (DPOEs) were measured in 102 normal-hearing and hearing-impaired ears to examine the sensibility, specificity, positive predictive value and negative predictive value of this test in a real clinical setting using two decision support systems. The first model only considered the presence or the absence of DPOEs in response to a 52 dB SPL stimulation intensity. The second model used two consecutive tests: i) the presence or the absence of DPOEs in response to a 52 dB SPL stimulation intensity, and ii) evaluation of the slope of each DPOE input-output function. The sensitivity of these two models varied between 1 and 0.83 whereas the specificity varied between 0.95 and 0.72 as a function of the frequency tested. The first model proved to be a very sensitive test, but the introduction of a second criterion of decision (i.e., the slope of DPOE input-output function) did not enhance the validity of the test.

[ORL surgery in Albucasis's treatise on surgery. A vision of cervicofacial surgical therapeutics in the year 1000]. / La chirurgie orl dans le traité de chirurgie d'Albucasis. Une vision de la thérapeutique chirurgicale cervico-faciale en l'an mille.

The work of the famous Arab doctor, Albucasis, is not well known to head and neck surgeons. However, the thirtieth time of his treatise on medicine is essentially a surgical textbook and includes many. Facts concerning otorhinolaryngology. Albucasis's complete work is an exhaustive compilation of late tenth century medical knowhow which ensured the link between ancient medicine, essentially of Greek origin, and modern western medicine. The important work of Jewish and Arab physicians in the early and late Middle Ages was necessary for the transmission of knowledge from the ancient near last to the modern western world. Among Albucasis's descriptions of surgical techniques, tonsillectomy and trachestomy are particularly interesting. In order to accurately formulate indications for surgery, Albucasis endeavors to present the signs and symptoms of pathological conditions requiring surgical treatment. Finally, Albucasis reveals himself to be a humanist, as well as a physician and surgeon.

[Screening of deafness in the young child. Value, techniques and initial results of products of acoustic distortion]. / Dépistage de la surdité du jeune enfant. Intérêt, modalités techniques, résultats préliminaires des produits de distorsion acoustique.

Distortion-product otoacoustic emissions are otoacoustic emissions evoked by two pure tones called primaries and proposed in order to provide a frequency specific investigation of the cochlea. This paper first reports complete input-output functions of distortion-product otoacoustic emissions for conventional audiometric frequencies in a population of 35 neonates without any risk for cochlear function. Distortion-product otoacoustic emissions could be useful, in association with evoked otoacoustic emissions and comportemental audiometry, to precisely evaluate the peripheral auditory system in infants and neonates.

[Does the use of nasal vasoconstrictor agents change tomodensitometric images of nasosinusal polyposis?]. / L'application de vasoconstricteur nasal modifie-t-elle les images tomodensitométriques des polyposes naso-sinusiennes?

This study compared the results of the CT scan of the paranasal sinuses in nasal polyposis patients before and after a topical vasoconstrictor application on the nasal mucosa. No change have been observed either on the maxillary and ethmoidal sinuses, or the middle meatus. On the other hand, an important retraction was observed on the nasal mucosa, in particular on the inferior turbinate. Then, the application of a topical vasoconstrictor on the nasal mucosa does not seem necessary in order to explore the sinuses in patients with nasal polyposis.

[Exposure of the facial recess through the ear canal. Value in posterosuperior retraction pockets (initial results)]. / Mise à plat du recessus facial par voie du conduit. Intérêt dans les poches de rétraction tympaniques postéro-supérieures (résultats préliminaires).

19 patients had surgery for progressive [17] and/or symptomatic [2] posterior attic retraction pockets involving the facial recess. Exposition of the suprapyramidal region was obtained after endaural incision by thinning the posterior wall of the ear canal and removing the posterior-superior portion of the tympanic sulcus. This technique is less complicated than intact canal wall tympanoplasty with mastoidectomy. Yet gives similar functional results. After a mean follow-up of 20.3 months, we have observed no residual cholesteatoma and no recurrent retraction pockets. Unlike posterior tympanoplasty, this technique makes it possible to meticulously remove the osteitic bone invariably found in the facial recess when there is infection of the retraction pocket.

[Sinusitis during intensive care. Prospective studies]. / Sinusites de réanimation. Etudes prospectives.

Two series of ICU patients, the first one with nasal endotracheal intubation, the other one with a tracheostomy, were included in a prospective and comparative study with repeated CT scans of the sinuses. Radiological sinus involvement is seen in both groups almost constantly; purulent sinusitis are often seen in both series. Unexplained fever should make us look for a sinusitis, even in patients with early tracheostomy. Moreover, our results ask for more study about associated causes, apart from nasal endotracheal intubation.