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Sébastien Schmerber

Publications and source records attributed to Sébastien Schmerber.

16 recordsLinked to original sources
PubMed2006

SLC26A4 gene is frequently involved in nonsyndromic hearing impairment with enlarged vestibular aqueduct in Caucasian populations.

Sensorineural hearing loss is the most frequent sensory deficit of childhood and is of genetic origin in up to 75% of cases. It has been shown that mutations of the SLC26A4 (PDS) gene were involved in syndromic deafness characterized by congenital sensorineural hearing impairment and goitre (Pendred's syndrome), as well as in congenital isolated deafness (DFNB4). While the prevalence of SLC26A4 mutations in Pendred's syndrome is clearly established, it remains to be studied in large cohorts of patients with nonsyndromic deafness and detailed clinical informations. In this report, 109 patients from 100 unrelated families, aged from 1 to 32 years (median age: 10 years), with nonsyndromic deafness and enlarged vestibular aqueduct, were genotyped for SLC26A4 using DHPLC molecular screening and sequencing. In all, 91 allelic variants were observed in 100 unrelated families, of which 19 have never been reported. The prevalence of SLC26A4 mutations was 40% (40/100), with biallelic mutation in 24% (24/100), while six families were homozygous. All patients included in this series had documented deafness, associated with EVA and without any evidence of syndromic disease. Among patients with SLC26A4 biallelic mutations, deafness was more severe, fluctuated more than in patients with no mutation. In conclusion, the incidence of SLC26A4 mutations is high in patients with isolated deafness and enlarged vestibular aqueduct and could represent up to 4% of nonsyndromic hearing impairment. SLC26A4 could be the second most frequent gene implicated in nonsyndromic deafness after GJB2, in this Caucasian population.

Adolescent↗
PubMed2006

Serous otitis media revealing temporal en plaque meningioma.

OBJECTIVES: To present a series of temporal en plaque meningiomas involving the middle ear or mastoid, whose main symptoms suggested a serous otitis media. STUDY DESIGN AND SETTINGS: Multicentric retrospective study reviewing clinical records originating from eight tertiary referral centers. MATERIALS AND METHODS: The clinical records of 10 patients presenting with signs and symptoms suggesting serous otitis media and whose neuroimaging studies revealed a temporal en plaque meningioma involving the middle ear or mastoid are reported. RESULTS: All the patients were women, ranging from 49 to 71 years old. The delay between the onset of symptoms and the diagnosis of meningioma varied from 1 to 10 years. All the patients underwent various procedures usually applied for the treatment of serous otitis media, which failed in all the cases, particularly ventilating tube placement, which was followed by severe episodes of discharge. In all cases, the computed tomographic scans showed three imaging signs: soft tissue mass filling the middle ear or mastoid, hyperostosis of the petrous bone, and hairy aspect of the intracranial margins of the affected bone. This imaging triad must alert the otologist of the possibility of intracranial meningioma. Magnetic resonance imaging was the method of choice to assess the diagnosis of intracranial meningioma involving the middle ear or mastoid. When analyzing management options, it appeared that conventional middle ear procedures were inefficient. CONCLUSION: Temporal en plaque meningioma involving the middle ear or mastoid can mimic a serous otitis media. A computed tomographic scan is recommended for cases of atypical or prolonged unilateral serous otitis media to investigate indirect signs of a meningioma, which has to be confirmed with magnetic resonance imaging.

Aged↗
PubMed2006

Audiometric analyses confirm a cochlear component, disproportional to age, in stapedial otosclerosis.

OBJECTIVE: To report the preoperative audiometric profile of surgically confirmed otosclerosis. STUDY DESIGN: Retrospective, multicenter study. SETTING: Four tertiary referral centers. PATIENTS: One thousand sixty-four surgically confirmed patients with otosclerosis. INTERVENTIONS: Therapeutic ear surgery for hearing improvement. MAIN OUTCOME MEASURES: Preoperative audiometric air conduction (AC) and bone conduction (BC) hearing thresholds were obtained retrospectively for 1064 patients with otosclerosis. A cross-sectional multiple linear regression analysis was performed on audiometric data of affected ears. Influences of age and sex were analyzed and age-related typical audiograms were created. Bone conduction thresholds were corrected for Carhart effect and presbyacusis; in addition, we tested to see if separate cochlear otosclerosis component existed. Corrected thresholds were than analyzed separately for progression of cochlear otosclerosis. RESULTS: The study population consisted of 35% men and 65% women (mean age, 44 yr). The mean pure-tone average at 0.5, 1, and 2 kHz was 57 dB hearing level. Multiple linear regression analysis showed significant progression for all measured AC and BC thresholds. The average annual threshold deterioration for AC was 0.45 dB/yr and the annual threshold deterioration for BC was 0.37 dB/yr. The average annual gap expansion was 0.08 dB/year. The corrected BC thresholds for Carhart effect and presbyacusis remained significantly different from zero, but only showed progression at 2 kHz. CONCLUSION: The preoperative audiological profile of otosclerosis is described. There is a significant sensorineural component in patients with otosclerosis planned for stapedotomy, which is worse than age-related hearing loss by itself. Deterioration rates of AC and BC thresholds have been reported, which can be helpful in clinical practice and might also guide the characterization of allegedly different phenotypes for familial and sporadic otosclerosis.

Adult↗
PubMed2005

Hearing results with the titanium ossicular replacement prostheses.

The purpose was to study the hearing results in patients receiving a Kurz titanium Bell partial ossicular replacement prosthesis (PORP) or an Aerial total ossicular replacement prosthesis (TORP). The study was a retrospective chart review in a tertiary otologic referral center. A computerized otologic database was used to identify 111 patients implanted with either a PORP or TORP prosthesis. Audiograms were reviewed and air-bone gaps were calculated for each patient. The improvement of the average air-bone gap (ABG) was 10.2 and 12.7 dB at 3 and 20 months after ossiculoplasty, respectively. Sixty-six percent of patients (73/111) had a postoperative air-bone gap of 20 dB or less. The ABG for the titanium PORP prosthesis was 14.3+/-9.7 dB, compared with 25.2+/-13.7 dB for the TORP prosthesis (P <0.05). The ABG to within 20 dB or less was obtained in the PORP group in 77% of the cases, versus 52% of the cases in the TORP group (P <0.05). Two extrusions of the prostheses were observed at 17 and 20 months after surgery (1.8%). Revision procedures for functional failure were carried out in 20 patients (18%). The rate of sensorineural hearing loss was 3.6%. The major factors influencing good audiometric results were the surgical procedure preserving the external auditory canal and the presence of the stapes. The best hearing results were achieved when a PORP was used in an intact canal wall (ICW) procedure, and the worst hearing results were achieved when a TORP was used in a canal wall down (CWD) procedure. The titanium Kurz prosthesis has been an effective implant at our institution for ossicular reconstruction.

Adolescent↗
PubMed2005

GJB2 and GJB6 mutations: genotypic and phenotypic correlations in a large cohort of hearing-impaired patients.

OBJECTIVES: To analyze the clinical features of hearing impairment and to search for correlations with the genotype in patients with DFNB1. DESIGN: Case series. SETTING: Collaborative study in referral centers, institutional practice. Patients A total of 256 hearing-impaired patients selected on the basis of the presence of biallelic mutations in GJB2 or the association of 1 GJB2 mutation with the GJB6 deletion (GJB6-D13S1830)del. MAIN OUTCOME MEASURES: The prevalence of GJB2 mutations and the GJB6 deletion and audiometric phenotypes related to the most frequent genotypes. RESULTS: Twenty-nine different GJB2 mutations were identified. Allelic frequency of 35delG was 69%, and the other common mutations, 313del14, E47X, Q57X, and L90P, accounted for 2.6% to 2.9% of the variants. Concerning GJB6, (GJB6-D13S1830)del accounted for 5% of all mutated alleles and was observed in 25 of 93 compound heterozygous patients. Three novel GJB2 mutations, 355del9, V95M, and 573delCA, were identified. Hearing impairment was frequently less severe in compound heterozygotes 35delG/L90P and 35delG/N206S than in 35delG homozygotes. Moderate or mild hearing impairment was more frequent in patients with 1 or 2 noninactivating mutations than in patients with 2 inactivating mutations. Of 93 patients, hearing loss was stable in 73, progressive in 21, and fluctuant in 2. Progressive hearing loss was more frequent in patients with 1 or 2 noninactivating mutations than in those with 2 inactivating mutations. In 49 families, hearing loss was compared between siblings with similar genotypes, and variability in terms of severity was found in 18 families (37%). CONCLUSION: Genotype may affect deafness severity, but environmental and other genetic factors may also modulate the severity and evolution of GJB2-GJB6 deafness.

Chromosome Deletion↗
PubMed2005

Time-intensity trading in bilateral congenital aural atresia patients.

In an effort to examine the rules by which information of bilaterally applied bone-conducted signals arising from interaural time differences (ITD) and interaural intensity differences (IID) is combined, data were measured for continuous 500 Hz narrow band noise at 65-70 dB HL in 11 patients with bilateral congenital aural atresia. Time-intensity trading functions were obtained by shifting the sound image towards one side using ITD, and shifting back to a centered sound image by varying the IID in the same ear (auditory midline task). ITD values were varied from -600 to +600 micros at 200 micros steps, where negative values indicate delays to the right ear. The results indicate that time-intensity trading is present in patients with bilateral aural atresia. The gross response properties of time-intensity trading in response to bone-conducted signals were comparable in patients with bilateral aural atresia and normal-hearing subjects, though there was a larger inter-subject variability and higher discrimination thresholds across IIDs in the atresia group. These results suggest that the mature auditory brainstem has a potential to employ binaural cues later in life, although to a restricted degree. A binaural fitting of a bone-conducted hearing aid might optimize binaural hearing and improve sound lateralization, and we recommend now systematically bilateral fitting in aural atresia patients.

Acoustic Stimulation↗
PubMed2005

Sacculo-collic pathway dysfunction accompanying auditory neuropathy.

CONCLUSIONS: In a patient with bilateral auditory neuropathy (AN), the vestibular-evoked myogenic potential (VEMP) was probably absent because of a neuropathy involving the inferior vestibular nerve and/or its end organ, the saccule. Our result can therefore be interpreted as a concomitant unilateral sacculo-collic neuropathy. We suggest the use of more precise terms to characterize AN patients with involvement of different parts of the inner ear and its innervations. We encourage detailed vestibular assessment in patients with AN in order to assess the co-existence of any symptomatic or asymptomatic vestibular disorder. Information such as that provided in this report will be valuable for clinicians caring for this group of patients. OBJECTIVE: AN is a disorder characterized by the absence or severe impairment of auditory brainstem responses in the presence of normal cochlear outer hair cell function as revealed by otoacoustic emissions (OAEs) and/or electrocochleography (ECoG). A variety of processes and etiologies are thought to be involved in its pathophysiology. In most literature reports the auditory profile of patients with AN is discussed. However, the extent of vestibular involvement, especially that involving the saccule, is not known. We performed vestibular tests to assess the status of the saccule in a patient with AN. MATERIAL AND METHODS: One patient with AN was studied. The patient was a right-handed 21-year-old female with chief complaints of hearing loss and speech perception difficulty. RESULTS: The auditory test results were consistent with the diagnosis of AN, i.e. absent auditory brainstem responses, moderate hearing loss, an inappropriately profound speech discrimination score and the presence of OAEs and measurable cochlear microphonics on ECoG. On neurological examination, gait and balance tests were normal. Ice-water caloric testing induced a sensation of dizziness in both ears. Short tone-burst VEMPs showed no response on left-ear stimulation and a biphasic response with normal latency and amplitude on right-ear stimulation.

Adult↗
PubMed2005

Long-term control of vestibular schwannoma after a translabyrinthine complete removal.

OBJECTIVE: The goal of this study was to determine the rate of recurrent vestibular schwannoma after a total removal via the translabyrinthine approach. PATIENTS: Between 1973 and 1995, 346 patients were operated on by a translabyrinthine approach. Ninety-one patients were included in a retrospective study for follow-up of 5 years or longer. RESULTS: The mean follow-up period for magnetic resonance imaging (MRI) examination was obtained after mean of 11 years in 91 patients. None of the 91 patients experienced a recurrent vestibular schwannoma on MRI. CONCLUSION: The translabyrinthine approach is a safe procedure for total definitive removal of a vestibular schwannoma and permitted the absence of tumoral recurrence in our series of 91 patients. A single gadolinium-enhanced MRI scan 5 years after surgery is advised in case of total removal. In case of any doubt about the quality of the tumoral removal, a proposed MRI follow-up schedule within 2 years and 5 years of surgery is an initial baseline pattern, and possibly thereafter repeated MRI examinations on clinical grounds.

Adult↗
PubMed2004

Large deletion of the GJB6 gene in deaf patients heterozygous for the GJB2 gene mutation: genotypic and phenotypic analysis.

Recent investigations identified a large deletion of the GJB6 gene in trans to a mutation of GJB2 in deaf patients. We looked for GJB2 mutations and GJB6 deletions in 255 French patients presenting with a phenotype compatible with DFNB1. 32% of the patients had biallelic GJB2 mutations and 6% were a heterozygous for a GJB2 mutation and a GJB6 deletion. Biallelic GJB2 mutations and combined GJB2/GJB6 anomalies were more frequent in profoundly deaf children. Based on these results, we are now assessing GJB6 deletion status in cases of prelingual hearing loss.

Connexin 26↗
PubMed2004

Vestibular-evoked myogenic potentials in three patients with large vestibular aqueduct.

An enlarged vestibular aqueduct (LVA) is a common congenital inner ear anomaly responsible for some unusual vestibular and audiological symptoms. Most of the cases show bilateral early onset and progressive hearing loss in children. The gross appearance on CT scan of the inner ear is generally normal. However, precise measurements of the inner ear components reveal abnormal dimensions, which may account for the accompanying auditory and vestibular dysfunction. Despite extensive studies on hearing and the vestibular apparatus, saccular function is not studied. To our knowledge this is the first report of saccular malfunction in three patients with LVA by means of vestibular evoked myogenic potentials. Conventional audiograms revealed bilateral severe sensorineural hearing loss in two patients and mixed type hearing loss in one patient. Two of the patients complained about vertigo and dizziness but vestibular assessments of the patients showed normal results. The diagnosis had been made by high-resolution CT scans and MR images of the skull that showed LVA in the absence of other anomalies. The VEMP threshold measured from the ear with LVA in two patients with unilateral enlargement of the vestibular aqueduct was 75-80 dB nHL whereas the threshold from normal ears was 95 dB nHL. The third patient with mixed type hearing loss and bilateral LVA had VEMP responses despite a big air-bone gap in the low frequency range. The VEMP in this patient was greater in amplitude and lower in threshold in the operated ear (the patient had a tympanoplasty which did not improve her hearing). These findings and results of other patients with Tullio phenomenon and superior semicircular canal dehiscence, who also showed lower VEMP threshold, confirmed the theory of a 'third window' that allows volume and pressure displacements, and thus larger deflection of the vestibular sensors, which would cause the vestibular organ to be more responsive to sound and pressure changes.

Adult↗
PubMed2004

Clinical evidence of the nonpathogenic nature of the M34T variant in the connexin 26 gene.

Mutations in GJB2 are the most common cause of congenital nonsyndromic hearing loss. The controversial allele variant M34T has been hypothesized to cause autosomal dominant or recessive nonsyndromic hearing impairment and some in vitro data has been consistent with this hypothesis. In this report, we present the clinical and genotypic study of 11 families (seven familial forms of nonsyndromic sensorineural hearing loss (NSSNHL) and four sporadic cases) in which the M34T GJB2 variant has been identified. The M34T mutation did not segregate with the deafness in six of the seven familial forms of NSSNH. Eight persons with normal audiogram presented a heterozygous M34T variation and five normal hearing individuals were composite heterozygous for M34T and another GJB2 mutation. Four normal hearing individuals with a documented audiogram were M34T/35delG and one was M34T/(GJB6-D13S1830)del. Screening a French control population of 116 subjects we have found an M34T allele frequency of 1.72%. This percentage was not significatively different from the prevalence of the M34T allele in the deaf population, which was 2.12%. All these data suggest that the M34T variant is not clinically significant in human and is a frequent polymorphism in France.

Connexin 26↗
PubMed2004

Intraoperative auditory monitoring in vestibular schwannoma surgery: new trends.

OBJECTIVE: To investigate the efficiency of a new method of brainstem auditory-evoked potential (BAEP) monitoring during complete vestibular schwannoma (VS) resection with attempted hearing preservation. MATERIAL AND METHODS: Dedicated software providing near real-time recording was developed using a rejection strategy of artifacts based on spectral analysis. A small sample number (maximum 200) is required and results are obtained within 10 s. Fourteen consecutive patients with hearing class A operated on for VS, in an attempt to preserve hearing, participated in the investigation. Postoperatively, 7 patients (50%) had useful hearing (hearing class A, 4/14; hearing class B, 3/14) on the operated side. Seven patients (50%) were reduced to hearing class D. RESULTS: Drilling of the internal auditory canal (IAC) and tumor removal at the lateral end of the IAC were identified as the two most critical steps for achieving hearing preservation. Intraoperative BAEP monitoring was sensitive in detecting auditory damage with useful feedback but its effectiveness in preventing irreversible hearing impairment was not demonstrated in this study. CONCLUSION: Combined BAEP and direct auditory nerve monitoring using the same equipment will be performed in the future in an attempt to enhance the chances of preventing irreversible hearing damage, and possibly to improve the hearing outcome significantly.

Adolescent↗
PubMed2004

Vein versus tragal perichondrium in stapedotomy.

OBJECTIVE: To assess, in otosclerosis surgery, whether the vein or the tragal perichondrium in stapedotomy with interposition yields the better long-term hearing outcome. STUDY DESIGN: A retrospective chart review of prospectively collected audiometric data of 452 ears. SETTING: Academic tertiary otology-neurotology referral center. PATIENTS: Four hundred fifty-two stapedotomies with interposition were performed in 412 patients (bilateral in 40 patients) by the senior author (R.C.) between 1987 and 1998. A tragal perichondrium graft was used in 314 cases and a vein graft was used in 138 cases as sealing material of the oval window. MAIN OUTCOME MEASURES: Audiometric data were recorded at 4 months, at 1 year, and at 3 years after surgery after American Academy of Otolaryngology-Head and Neck Surgery guidelines, except for thresholds at 3 kHz, which were not available and which were replaced with those at 4 kHz. RESULTS: There were no significant intergroup differences in initial or late postoperative hearing outcome with regard to change in the pure-tone average bone conduction and air-bone gaps, or sensorineural hearing loss. Ears treated with a vein graft showed statistically better postoperative 2-kHz air-bone gap closure (p =0.0157), but the pure-tone average air-bone gap difference was not significant. Postoperative air-bone gap closure to within 10 dB was achieved in 91% of cases in the vein group and in 76% of cases in the perichondrium group. Specific study of the bone conduction level at 4 kHz showed a sensorineural hearing loss greater than 10 dB in 8% of cases in the vein group and in 11% of cases in the perichondrium group. One case of complete sensorineural hearing loss was observed with a tragal perichondrium graft (0.22%). CONCLUSION: These results suggest that the vein should be preferred to the tragal perichondrium in stapedotomy with interposition.

Audiometry, Pure-Tone↗
PubMed2003

Facial nerve schwannoma in revision stapedotomy surgery.

We describe a male patient who presented a progressive conductive unilateral hearing loss 20 years after otosclerosis surgery. Computed tomography (CT) scan and magnetic resonance imaging (MRI) findings suggested a facial schwannoma in its tympanic segment. At the time of revision surgery, a facial schwannoma was found to originate at the tympanic segment, pushing the prosthesis out of the oval window fenestration. The Teflon-piston was repositioned with difficulties in the central platinotomy, and the facial schwannoma was left intact.

Biopsy, Needle↗
PubMed2002

Perception of slow pitch and roll body tilts in bilateral labyrinthine-defective subjects.

The aim of the present study was to examine whether the perception of slow body tilts in total darkness was affected by a complete loss of vestibular function. Four blindfolded bilateral labyrinthine-defective subjects (LDs) and 12 normal subjects (Normals) were seated and immobilized with large straps against the back of a rotating L-shaped platform, and were passively displaced from the upright at 0.05 degrees x s(-1) in the pitch and roll dimensions. Subjects were asked to detect the slow change in their body orientation, by indicating as soon as possible the direction of tilt. After a brief period of practice observed for all LDs at the beginning of the session, results showed no significant difference between LDs and Normals in the mean detection threshold recorded for each direction of tilt. The mean perceptual threshold was 4.4 versus 5.1 degrees in the roll dimension, and 6.1 versus 6.1 degrees in the pitch dimension, for the LDs and Normals, respectively. These findings indicate that the accurate perception of body orientation in quasi-static conditions is mainly allowed by somatosensory information rather than by otolithic inputs.

Adult↗