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J Trotoux

Publications and source records attributed to J Trotoux.

At least 37 records · Page 2Linked to original sources
PubMed1993

[Screening of deafness in the young child. Value, techniques and initial results of products of acoustic distortion].

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.

Audiometry↗
PubMed1992

Spontaneous and evoked otoacoustic emissions in preterm neonates.

Spontaneous (SOEs) and evoked otoacoustic emissions (EOEs) were recorded in a group of preterm neonates (N = 134 ears) in order to study the basic properties of SOEs and EOEs as a function of gestational age. In the study, it was found that: 1. EOEs were recorded in 93% of the tested ears; 2. SOEs were recorded in 61% of the tested ears; 3. there were no statistically significant variations of EOE amplitude with gestational age; 4. EOE spectrum did not vary with age; and 5. the two main factors influencing EOE amplitude were the SOE presence and the fast Fourier transform spectrum, especially the lower limit of the spectrum. Thus, the maturation of outer hair cell properties appears to be complete at 32 weeks of gestational age. Because a number of infants at risk for hearing loss are preterm babies, screening for EOEs, an objective, rapid, and nontraumatic technique, may prove useful in evaluating peripheral auditory dysfunction in preterm neonates.

Cochlea↗
PubMed1992

Distortion-product otoacoustic emissions in neonates: normative data.

Distortion-product otoacoustic emissions (DPOEs) are otoacoustic emissions evoked by two pure tones and used in order to provide a frequency specific assessment of the mechanical properties of the cochlea. This paper first reports complete input-output DPOE functions for audiometric frequencies between 867 Hertz and 8 kHz in a normal neonate population (normative data). DPOE results were analyzed as a function of evoked otoacoustic emission (EOE) properties. Neonates having normal EOEs have large DPOEs. DPOE amplitudes in neonates are larger than in adults. Neonates with atypical EOE frequency spectrum without low frequency components had normal DPOE input-output functions only for high frequencies (above 2 kHz). DPOEs could be useful, in association with EOEs, to precisely evaluate the auditory peripheral function in neonates.

Humans↗
PubMed1992

[Is facial nerve visible on magnetic resonance imaging?].

The internal architecture of the parotid gland was studied by nuclear magnetic resonance (NMR) imaging, particular attention being paid to the intra-parotid portion of the facial nerve. Currently available apparatuses provide high resolution images of previously poorly elucidated anatomic details. Certain authors consider that images in the axial plane in T1 allow direct visualization of the facial nerve and its branches in the form of low frequency linear signals within the gland. The present study, based on radio-anatomic correlations and date determined in a healthy volunteer, demonstrated that these structures correspond in fact to segments of the excretory canal tree, the facial nerve and its branches being invisible on NMR imaging. It is not possible, therefore, to determine the location of a parotid tumor in relation to these nerve elements using this imaging technique.

Facial Nerve↗
PubMed1992

[Nasal and sinusal polyposis. Semiology and values of magnetic resonance imaging].

Twelve patients with nasal polyposis were examined with magnetic resonance imaging (MRI) prior to surgical ethmoidectomies (20 ethmoidectomies). MRI signal was analyzed in correlation with surgical findings in order to define the semiology of nasal and sinuses polyps. One of the most important point of this semiology is based on the analysis of sequences after administration of gadolinium. MRI seems an interesting method for analysing the extension of nasal polyposis and could be useful for ENT surgeons before an endoscopic nasal surgery.

Adolescent↗
PubMed1992

[Acoustic distorsion products. A systematic analysis of technical parameters. How to explain the results?].

The aim of this study was to define the most interesting parameters useful for a clinical application of acoustic distortion products (mainly, F1 and F2 primaries frequencies and levels). The most interesting F1 and F2 primaries level in order to separate subjects with a normally-hearing function and patients with a sensorineural hearing loss is 50 dBHL. This result can be explained by some physiological properties of cochlear mechanisms.

Acoustic Stimulation↗
PubMed1992

[Deafness screening in children by otoacoustic emissions. Current data].

Hearing impairment should be detected in early childhood. Among available screening techniques, acoustic oto-emission testing is a rapid, reliable, noninvasive method which specifically investigates peripheral hearing but does not provide data on auditory nerve centers. This functional test should be carried out within a few days of birth in infants with risk factors for hearing impairment.

Hearing Disorders↗
PubMed1991

Objective low-frequency audiometry by distortion-product acoustic emissions.

The aim of this study was to measure distortion-product otoacoustic emissions (DPOEs) in a clinical setting. First, DPOE input-output functions were automatically realized to determine the ratio of the pure tones (primaries) f2 and f1 that would elicit the most significant DPOE input-output function. The DPOE input-output functions presented two separate portions for the f2/f1 ratio, ranging from 1.18 to 1.26: (1) below 60-dB sound pressure level (SPL), a saturating portion with a DPOE detection threshold at 36-dB SPL; and (2) above 66-dB SPL, a linear portion. For other f2/f1 ratios, DPOE input-output functions had a more linear behavior. The DPOEs generated by primary intensities below 60-dB SPL, which show saturating behavior, probably have their origin in the properties of outer hair cells. This indicates that DPOE measurements in a clinical setting must be realized with precise stimulus values: (1) f2/f1 ratio near 1.22, and (2) primary intensities below 60-dB SPL. Second, DPOE input-output functions were realized for DPOEs varying from 707.5 to 342 Hz. No more saturating plateau could be observed with DPOEs below 512.5 Hz, suggesting that active mechanisms are absent below 725 Hz within the human cochlea. These data permit us to establish the bases of an objective low-frequency audiometric test.

Acoustic Stimulation↗
PubMed1991

Quantitative assessment of human cochlear function by evoked otoacoustic emissions.

The amplitudes of evoked otoacoustic emissions (EOE) and their detection threshold were measured in 44 normal young adults and 118 patients with two categories of cochlear dysfunction, acoustic trauma and presbycusis. A different method was used for each category: detection of click EOE or of stimulus frequency emissions. A partial correlation and multivariate analysis was performed for both groups of results to investigate the relations between EOE threshold one pure tone audiometric thresholds (250 to 8000 Hz). Only one significant correlation was found, linearly relating EOE threshold and hearing threshold at 2 kHz (P less than 0.001), independently of the origin of cochlear dysfunction. It suggests that EOE threshold is not frequency-specific since the frequency of EOE at threshold was nearly always close to 1 kHz. A simple model is proposed, based on the assumption that EOE amplitudes and threshold are proportional to the total number of residual active sites in the organ of Corti, i.e. to the total length of active basilar membrane. It is shown that this model accounts for the results disclosed by the statistical analysis and fits the experimental data. It can be used for quantitatively predicting the residual cochlear activity of a patient. However, the EOE threshold is only sensitive to already important cochlear alterations and this parameter does not seem to allow a follow-up of early stages of cochlear dysfunction.

Adolescent↗
PubMed1991

Vertical partial laryngectomy: a critical analysis of local recurrence.

The purpose of this study was to evaluate local recurrence following vertical partial laryngectomies in 416 patients with either T1N0M0 or T2N0M0 glottic carcinoma. Local failure was reported according to the T stage, the precise tumor location within each stage, the true vocal cord mobility, and the surgical procedure performed. No local recurrences were observed among 42 patients who underwent thyrotomy and cordectomy when the tumor was confined to the middle third of the mobile true vocal cord. Local failure occurred in 8 of 111 (7.2%) patients in whom hemilaryngectomy was performed for tumors confined to one mobile true vocal cord. There was a diverse group of lesions within each T stage that responded differently to the surgical approaches. The differences in the initial recurrence rates are discussed in terms of careful preoperative assessment and choice of surgical technique for early glottic carcinoma.

Adult↗
PubMed1991

[Prefabricated free grafts and neovascularized free grafts. 150 cases in rats].

The use of vascularized, composite and prepared free transplants is a recent technique. Two types of transplants were grafted in rats (150 operated cases). For the prefabricated free transplants, each component remains vascularized by rami of the main pedicle: vessels, nerves, bone, periosteum, cartilage, muscle, skin (50 cases). The graft is transplanted immediately. Neovascularized free transplants are quite different, the various components being laid around the vascular pedicle (100 cases). Neovascularization revascularizes the components. The free graft is transplanted 5 weeks after being prepared. The period of observation ranges from 3 to 12 months. Observation includes macroscopy, arteriography, histology and intravascular dye injections. The results with prefabricated free transplants show normal vascularization of soft tissues. There is bone in all cases, it is normal in 80% of cases. In neovascularized transplants, the bone is normal in 33% of cases only, and totally resorbed in 46%. Prefabricated free transplants produce better results than neovascularized free transplants and must be preferred. The merit of these composite free transplants is that they produce free transplants selectively, using various tissues and chosen vascular pedicles. These transplants are a useful and futuristic alternative for highly sophisticated reconstructive surgery.

Animals↗
PubMed1991

[Pseudotumoral salivary localization of Destombes-Rosai-Dorfman syndrome. Hemophagocytic histiocytosis. Diagnosed by bilateral submandibular and parotid involvement].

We report one case of pseudotumoral salivary location of the Rosai-Dorfman syndrome, with a favorable outcome, occurring in a 32-year-old man from Guadeloupe. The clinical, biological and clinicopathological features of this syndrome, as well as the pathogenetic hypotheses, are summed up. In this case, no bacterial, fungal, parasitic or viral agent was discovered. The subject presented with no immune abnormality likely to account for the persistence and intensity of the histiocytic infiltration with lymphophagocytosis associated to the lymphoplasmocytic infiltration. The rarity of ENT, and more specifically salivary, locations is emphasized. The importance of the detection of possible immune abnormalities in such patients is demonstrated by the outcome of the syndrome being more often unfavorable when such abnormalities are present.

Adult↗
PubMed1991

[Combined approach to malignant tumors of the ethmoid and other paranasal sinuses. Principles and results].

The authors present their experience concerning combined transfacial and neurosurgical procedures in the treatment of carcinomas of the ethmoid sinuses. 109 ethmoid-spheno-orbital tumors were treated at our department from 1982 to 1990: 85 were located into the ethmoidal and/or sphenoidal sinuses; 78 of these were malignant. Among the 65 ethmoidal carcinomas which were operated through a combined route, 48 underwent an induction chemotherapy and 19 a post-operative radiotherapy. The surgical technique is detailed, mostly the intra-cranial approach and the reconstruction of the cranial basis. Clinical results, and particularly the actuarial survival rates are discussed. The 5-year actuarial survival rate is 40% for all first hand ethmoidal adenocarcinomas. The figure reaches 52% for the patients without intra-cranial extension. At last, the 5-year actuarial survival rate is 100% for patients having a complete clinical response to induction chemotherapy.

Actuarial Analysis↗
PubMed1991

[Acoustic distortion products. Clinical values and limitations in the study of low frequencies].

Distortion products are otoemissions produced when the cochlea is stimulated by two pure, continuous sounds f1 and f2. The most ample distortion product in Man corresponds to a frequency of 2f1-f2. The aim of our work is to appreciate the possibilities to study the distortion products for the exploration of low frequencies in Man. Three populations of subjects have been studied: young subjects have been studied: young subjects with a normal hearing, subjects with pathological otoscopic findings in spite of a normal hearing, subjects with pathological otoscopic findings in spite of a normal audiometric study, and subjects with endocochlear perceptive deafness. The major result of this study was to demonstrate that the lowest frequency that can be explored with distortion products is 750 Hertz.

Acoustic Stimulation↗
PubMed1991

[Free forearm flap used in the reconstruction of the cervico-cephalic region. 43 cases].

The free neurovascular antebrachial transplant was described by Yang-Guofan in 1978. In 1981, we brought the description of this free transplant to Europe. Forty-three antebrachial grafts were made to reconstruct the cervicocephalic extremity. We had various indications: floor of the mouth and base of the tongue: 18 cases, facial structures: 7 cases, posterior wall of the pharynx: 9 cases, rescue surgery for esophagoplasty: 6 cases, mandible: 2 cases (using a bone rod taken from the radius), internal aspect of the cheek: 1 case. All grafts were revascularized. In 41 cases, the indications were carcinological, the last 2 cases being benign lesions. The early postoperative mortality included 1 case, not related to the nature of the operation (neoplasm). There was no failure of free transplants. Surveillance was ensured every half-hour during 12 hours, then every 3 hours. Discriminating sensation was recovered in 39 of 43 cases. Mandibular bone reconstructions were knit at the 3rd month. The main disadvantage of removing this graft is esthetic, as it leaves a considerable scar on the forearm. The free antebrachial transplant provides an effective solution to the reconstructions of the cervicocephalic extremity, when a narrow, thin, supple, reinnervated, compound transplant is needed.

Adolescent↗
PubMed1991

Progressive hereditary deafness with predominant inner hair cell loss.

This paper presents the first case of human genetic hearing loss due to predominant inner hair cell damage investigated by psychoacoustic audiometry, auditory brainstem responses (ABR), evoked acoustic emissions (EAEs), and distortion product otoacoustic emissions (DPOEs). The genetic transmission was an autosomal dominant inheritance. The audiogram pattern was a dominant high-frequency hearing loss. EAE and DPOE properties were normal. Bronx waltzer mutant mouse with genetically determined predominant inner hair cell defects provide an interesting model to study this congenital deafness. This rare congenital deafness with predominant damage to inner hair cells cannot be detected by neonatal screening techniques using EAEs or DPOEs.

Adult↗
PubMed1991

[Study of the cochlea by evoked otoemissions. Physiological interpretation of results].

Amplitudes and detection thresholds of evoked otacoustic emissions (EOE) were measured in various groups of subjects: 44 normal young adults, 80 patients with presbycusis and 38 patients with acoustic trauma. Relations between these EOE parameters and tonal audiogram were analyzed. Surprisingly, EOE detection threshold at 1 kHz was strongly correlated with auditory threshold at 2 kHz and no other one. This result demonstrates that some EOE parameters are not frequency-specific. A simple model is implemented in which it is assumed that EOE amplitudes are proportional to the global cochlear activity. This model fits very well experimental data and allows a quantitative evaluation of the residual cochlea. The domain of validity of EOE test in clinics has therefore been precised.

Audiometry↗