Search PubMed⌕ Search

Biomedical subjects

O Deguine

Publications and source records attributed to O Deguine.

36 records · Page 2Linked to original sources

[Cochleovestibular disorders associated with hemifacial spasm: an outcome after microvascular decompression of the facial nerve].

Twelve patients underwent microvascular decompression by retrosigmoid approach to relieve severe hemifacial spasm. The surgery was done under intraoperative monitoring of the auditory function. Assessment at Day 2, Day 10, 2 months and 6 months after the operation found that the surgery had resulted in 9 recoveries, 3 improvements and 1 failure. Brain stem auditory evoked potentials monitoring showed that the interposition of Teflon between the vascular loop and the facial nerve is a critical stage for the auditory function. Six of the twelve patients were also complaining of cochleo-vestibular disorders: vertigo and tinnitus, or hearing loss and tinnitus, or vertigo alone. The surgery improved at least one of these cochleo-vestibular symptoms in each one of the patients. There was one hearing improvement, vertigo disappeared in three cases out of four, and tinnitus disappeared in four cases out of five. The possibility of a concomitant compression of cochleo-vestibular and facial nerve was investigated using cochleovestibular tests, radiological data and intra-operative findings.

Aged↗

Selection criteria for cochlear implants in children.

OBJECTIVE: To determine the selection criteria for cochlear implantation in children. SETTING: Hospital pediatric implant center. PATIENTS AND INTERVENTIONS: Selection of patients depends on medical evaluation, audiometric data, speech discrimination, communication skills, cognitive skills, and psychosocial factors. Patient selection is based on tonal audiometry, computed tomography, magnetic resonance imaging, and electrophysiologic tests. Side of implantation is chosen according to cochlear structure, duration of deafness, and dominant handedness. RESULTS: Ninety-eight cochlear implantations with the Nucleus multichannel implant have been performed at this center since 1990. CONCLUSION: The selection of children for cochlear implantation require close collaboration between the pediatric surgical team, the educational team, and the family.

Auditory Threshold↗

[Cochlear implants in the elderly].

The authors present a retrospective and multicenter study of 18 elderly patients aged above 60 years-old who underwent a cochlear implantation by comparing them with a population of adult patients. The purpose of this study is to evaluate the utility and benefits of cochlear implantation in the elderly by analyzing the clinical data and the results of a questionnaire assessing the use of the implant and the consequences of implantation on the quality of life. The results of this study indicate that the improvement of quality of life in the elderly is similar compared to a control group of adult patients.

Aged↗

[Conservation of residual hearing after cochlear implantation].

Indications for cochlear implantation have been expanded to include severely hearing impaired adults and may increase the number of patients presenting with preoperative residual hearing. Conservation of residual hearing may allow better performance with an implant. However, conventional thought is that implantation destroys auditory structures involved in residual hearing. This study was undertaken to assess if there are general or surgical factors intervening in the conservation of residual hearing in a sample of multichannel implant recipients. A retrospective study on 50 adult cochlear recipients with preoperative residual hearing has been undertaken. Sixteen of 50 implanted subjects (32%) were found to have conserved their residual hearing. Among them, seven patients have clinically non-significant changes of hearing. Age, side of implantation, gender and etiology did not influence the outcome of residual hearing. Round window ossification, ossification of the cochlea, length of insertion, approach and site of insertion (scala tympani vs.scala vestibuli) were not found to be statistically significant between the population having lost and the population having conserved residual hearing. This study emphasizes the need to undertake a larger multicenter longitudinal study to determine the existence of factors related to the conservation of residual hearing.

Adolescent↗

Prenatal lesioning of vestibular organ by aminoglycosides.

The effects of gentamicin administrated to gravid mice on the vestibular hair cells of their offspring were investigated. Scanning electron microscopy showed the effect to be dose-dependent and age-dependent, and there was a different sensitivity to toxicity for each of the three types of vestibular receptors. The destructive action of gentamicin on the vestibule before birth provides a mechanism to study the influence of the vestibular system on the central nervous system throughout its development.

Aminoglycosides↗

Comparison of postoperative results in suspected and confirmed cases of perilymphatic fistula.

Perilymphatic fistula is suspected on clinical symptoms, but must be confirmed by surgery. Exploratory tympanotomy was realized in 38 patients, presenting one or several symptoms of perilymphatic fistula. A leak was observed in 23 patients (61%). When a leak was not observed, the oval and round windows were filled with connective tissue. Preoperative and post-operative symptoms were compared in patients with or without leak: there was not significant difference between the two groups of patients. 63% of patients presenting fluctuant or sensorineural hearing loss improved or stabilized hearing after surgery. One patient, presenting a post-traumatic total deafness due to round window rupture, was immediately operated on, and recovered normal hearing. 84% of patients with vertigo or dizziness improved after surgery. The authors conclude that exploratory tympanotomy should be widely proposed when a perilymphatic fistula is suspected. Oval and round window should be grafted with connective tissue even if a leak is not observed.

Adolescent↗

Criteria for selecting the side for cochlear implantation.

Choice of the side for cochlear implantation should take into account peripheral (extracortical) factors and central (cerebral dominance) factors. From 111 patients implanted with a Nucleus device, the authors found that significant peripheral factors were the degree of cochlear ossification, the duration of deafness before cochlear implantation, and the preoperative promontory test dynamic range (degree of response on the promontory test in decibels); cause of deafness and residual hearing were not correlated with speech discrimination. Cerebral dominance was indirectly determined by handedness. Handedness laterality was determined by a questionnaire. There was no significant difference in results between patients implanted on their dominant side and patients implanted on their nondominant side. When ears are different according to their peripheral factors, the authors suggest implanting the better ear, provided there is no significant hearing in that ear. When both ears are identical, the side of implantation should be the side of handedness laterality to facilitate device manipulation (a practical reason).

Adolescent↗

[Surgical technique and results of cochlear implant in normal or ossified cochlea].

The authors describe the surgical technique and results of the Nucleus device in 50 recipients. Cochlear ossification was present in one third of patients. Total insertion was possible in all cases with a partial ossification (< or = 8 mm), and once in a case with a total ossification (> 8 mm) of the scala tympani of the basal turn. Results were not significatively different in normal cochleas and in ossified cochleas. The authors describe a per-operative algorithm in front of a basal turn ossification, emphasizing on the insertion in scala vestibuli through the oval window. According to the results, the authors prefer the use of a multi-channel cochlear implant than a monochannel implant, even in ossified cochleas.

Adolescent↗

[General principles of conception of cochlear implants].

Cochlear implants have greatly been developed on last ten years. Their diversity makes their use and choice more complex. The authors expose simply the physiopathology of the implanted auditory system and basic principles of cochlear implants. Cochlear implants are caracterised by the number of channels and electrodes (monochannel, multichannel), the strategy of encoding (analogiq, digital), the transmission of signal (per-cutaneous, electro-magnetic induction), the site of stimulation (extra or intra-cochlear), the signal wave (sinusoid, pulse), the diffusion of current (monopolar, bipolar).

Cochlear Implants↗

[Repair of deglutition troubles after partial surgery of the pharyngolarynx with injection of collage. Apropos of 9 cases].

The authors report their experience treating nine patients with swallowing disorders following partial surgery of the laryngo-pharynx. GAX collagen (Phonagel), resistant to collagenase was injected into the laryngeal structures to protect the trachea, yielding a satisfactory long term result. A description of the injection technique is given particularly with functional reconstructive laryngectomies and hemipharyngolaryngectomies. The results concerning functional improvement and weight gain are evaluated over a five month period.

Collagen↗