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S Schmerber

Publications and source records attributed to S Schmerber.

At least 19 recordsLinked to original sources
PubMed2006

[Middle ear cholesteatoma].

Cholesteatoma is a serious form of chronic otitis media. The aim of this paper is to present the state of the art of disease management, including recent data from the literature and the authors' derived from their Mentors' teaching, Professor Pierre Roulleau (Paris, France) and Professor Robert Charachon (Grenoble, France). The main recent advances concern the use of cartilage grafts to reconstruct the canal wall and/or tympanic membrane (allowing a significant reduction in residual cholesteatoma) and progress in medical imaging allowing more acute preoperative determination of extension of the cholesteatoma (in order to propose an optimally designed surgical technique) and a less invasive postoperative follow-up.

Cholesteatoma, Middle Ear↗
PubMed2006

[Lemierre's syndrome: literature review].

OBJECTIVES: Our aim was to recall the pathogenesis, clinic aspects and therapeutic options for Lemierre's syndrome. PATIENTS AND METHODS: This was a retrospective study (1998-2005) of 4 patients, 3 males and 1 female, average age 22 years (18-30). Bacteriological samples, a chest radiograph and a cervical and thoracic CT-scan with injection were available for all patients who were given broad spectrum antibiotic therapy for 3 to 6 weeks. Surgical treatment was necessary for 3 patients. A review of the literature from Medline was performed. RESULTS: Three patients had a peritonsillar abscess. All of them exhibited thrombophlebitis of the internal jugular vein or one of its tributary branches. In all patients, metastatic infections were noted. In one, arthritis and mediastinitis were associated. The causal microorganism was Fusobacterium (necrophorum--2, nucleatum--1) in three patients. In one, bacteriological samples were negative. Transfer to an intensive care unit was necessary for one patient. There were no deaths. CONCLUSIONS: Lemierre's syndrome is a rare but acute medical condition which concerns young immunocompetent people. The pathogenesis consists of the development of infectious thrombophlebitis in the internal jugular vein or one of its tributary branches caused by a focal sepsis, localized in most the cases in the oropharynx, leading to metastatic infections, generally to the lung. Treatment is medical but surgery is sometimes required.

Adolescent↗
PubMed2006

[Dehiscence of the anterior semicircular canal and otosclerosis: a case report].

UNLABELLED: The dehiscence of the anterior semicircular canal is a new clinical entity, it is necessary to consider this when a gusher occurs during stapedial surgery. CASE REPORT: We report a rare case of dehiscence of the anterior canal associated with otosclerosis. This was revealed by a gusher during the initial stapedectomy. At 3 months, an obliteration of the dehiscence was necessary by middle cranial fossa approach (persistant vestibular symptoms), seven months later. Revision stapedial surgery resulted in complete closure of the air-bone-gap. CONCLUSION: High resolution CT scans of the temporal bone are the key to diagnosis. It is necessary to appreciate this pathology with advances in canal and vestibular surgery.

Early Diagnosis↗
PubMed2006

[Sphenoid sinus mucocele of unusual aetiology and location].

UNLABELLED: Mucoceles of the sphenoid sinnus are rare. 140 cases have been reported in the literature. PURPOSES: We review a case and discuss: 1) pathophysiology and diagnosis of mucoceles; 2) etiologies, anatomical variants, clinical manifestations and treatment of sphenoidal mucoceles. MATERIAL AND METHOD: Case report and literature review. CASE REPORT: An 18-year-old female, with no past medical history was hospitalized for right fluctuating monocular blindness. MRI and CT scan facilitated the diagnosis of right clinoid mucocele with compression of the optic nerve. Imagery also revealed fibrous dysplasia of the anterior skull base which probably induced the mucocele formation. The mucocele was successfully decompressed during endoscopic sinus surgery. Postoperative course was unremarkable. At four months post surgery there was no recurrence of ophtalmological symptoms. DISCUSSION-CONCLUSION: The pathophysiology of mucoceles remains uncertain. Diagnosis is based on imagery (CT scan, RMI). Imagery allows accurate location of the mucocele, defines any concomitant pathology and oulines important anatomical structures necessary for safe endoscopic sinus surgery. The association of fibrous dysplasia and an anterior clinoidal mucocele is exceptional. To our knowledge this is the only report in the literature. Ophtalmologic symptoms with a risk of blindness require urgent surgical treatment. Surgery involves decompression, ideally endoscopically.

Adolescent↗
PubMed2005

[Long term results of congenital middle ear cholesteatoma in children].

OBJECTIVES: To report the long term results of congenital cholesteatoma of the middle ear in children. PATIENTS AND METHODS: Retrospective study of thirty two children with 33 congenital cholesteatoma (1 bilateral cholesteatoma) operated on by the same surgeon. The mean age was 6 years. The most common clinical presentation was unilateral hearing loss. A trans-canal approach was performed in 4 cases and an intact canal wall technique in 29 cases. A two staged surgery was necessary in 28 patients, whom a residual cholesteatoma was observed in 7 patients. A third stage was performed in 11 patients because of a residual cholesteatoma in 2 two cases and a functional failure in 9 cases. RESULTS: At five years postoperative audiometry (air bone gap inferior or equal to 20 dB HL), a functional success was obtained in 50% of cases. CONCLUSION: The diagnosis of congenital cholesteatoma must be evoked in every atypical otitis media with effusion or unilateral transmission hypoacusis. The intact canal wall technique in two stages is the most appropriate treatment, since congenital cholesteatoma in children appears aggressive in a well pneumatized mastoid. The choice for an intact canal wall technique is also justified by the ambition of a conservative surgery in the young child. The functional results are generally satisfactory in early diagnosed cases. Thus, ENT and pediatric physicians have a unique role in detecting congenital cholesteatoma in the early period of life, and in ensuring a long term follow-up.

Adolescent↗
PubMed2005

[Ossiculoplasty with KURZ titanium prosthesis].

OBJECTIVES: Report the functional and anatomic results of ossicular reconstruction by titanium prosthesis. MATERIALS AND METHODS: Retrospective chart reviews were performed for 111 patients who had undergone titanium ossicular implants between November 1998 and 2002 (61 PORP, 50 TORP). The anatomical and audiometric data were analyzed on average at 3 and 20 months. RESULTS: At 20 months, the improvement of air-bone-gap mean was 12.7 dB with better results at low frequencies. The global success rate was 66% (PORP 77%, TORP 52%). It decreased significantly in the open techniques. Extrusion rate was low (2/111) and the labyrinthization rate was 3.6%. Twenty patients required a surgical revision (18%). In 9 patients, the prosthesis was too short. At long-term follow-up, the gains were stable in 60 patients, improved in 32 patients and worsened in 19 patients. CONCLUSION: The success rate is higher in the group of the PORP with the closed technique. The stability of the TORP in open technique still remains problematic. In all cases, the risk of extrusion requires a large cartilage graft recovering the plate of the prosthesis. The high rate of luxation (9/111 prosthesis too short) has led us to increase slightly the length of the prosthesis (+1.22 mm mean).

Adolescent↗
PubMed2005

[Reconstruction after tumor resection of the anterior skull base with an of abdominal fat graft].

OBJECTIVES: Reconstruction of the anterior skull base is a surgical stage as significant as tumor removal. The quality of the reconstruction is the primary determinant of postoperative mortality, morbidity. The aim of our work was to assess the results of a reconstruction process combining: 1) a pericranium graft held by biological glue to complete the dura mater; 2) an abdominal fat graft supported by a Silastic arch to maintain the neurological structures. PATIENTS AND METHODS: This was a retrospective study. 55 patients (44 men and 11 women), 59 mean age (14 - 78), were analyzed. 45 had a malignant tumor and 10 a benign tumor. 35 patients were treated using a mixed approach and 18 using a trans frontal-sinus approach alone. Forty-three patients treated for a malignant tumor underwent postoperative radiotherapy. Results were analyzed according to 3 periods: 1) immediate postoperative period (<25 days); 2) early postoperative period (25 days - 3 months); 3) late postoperative period (> 3 months). RESULTS: None of the patients were lost to follow-up. The average follow up was 84 months. All periods considered together, we had five (9.4%) graft infections, 6 (11.3%) CSF leaks and 1 (1.8%) cases of meningitis. CONCLUSION: We use a simple technique for reconstruction. Postoperative complications were exceptional, even after postoperative radiotherapy. Medium and long-term results are good and similar to those obtained with other processes used for reconstruction of the anterior skull base reconstruction.

Adipose Tissue↗
PubMed2005

[Vestibular neurotomy versus chemical labyrinthectomy for disabling Menière disease].

OBJECTIVE: To evaluate the efficiency on the vertigos and the impact on the audition of the vestibular neurotomy (VN) and the chemical labyrinthectomy (CL) in patients with severe Menière's disease, in order to determine the precise place for each technique in treatment algorithm. METHOD: Retrospective study of 71 VN (performed between 1986 and 2003) and 35 CL (performed between 1997 and 2003). These two treatments both aim at obtaining a vestibular deafferentation in order to free definitely the patient of vertigo manifestations. Vestibular results have been assessed by caloric tests performed before and 6 months after treatment. Subjective success was evaluated by searching for recurrent attacks of vertigo and by the AAO-HNS (American Academy of Otolaryngology-Head and Neck Society) scale of subjective evaluation of vertigos (follow-up of 6.4 years after VN and 2.4 years after CL). Pure tone audiometry before treatment and then 6 months later was performed. Complications of two types of treatment were recorded and evaluated. RESULTS: In 90% of the cases after VN and 86% of the cases after CL, caloric tests indicated a strong vestibular hyporeflexy (hypovalence > 90%). Attacks of vertigo reoccurred in 5.6% of the cases when the hyporeflexy was strong and 85.7% of the cases when it was weak. The quality of the vestibular results on vertigo depends on the degree of hypovalence after treatment. An improvement of the AAO-HNS scale have been obtained in 93% of the cases in the NV group and in 81% of the cases in the LC group. Attacks of vertigo were recurrent in 7% of the patients operated on by VN and 11.4% of the patients treated by CL. Mean pure tone auditory thresholds changed from 50.24 dB HL to 55.64 dB HL (p=0.003) in the VN group and from 69.11 dB HL to 74.51 dB HL (p=0.41) in the CL group. Comparison of the variations of the mean pure tone auditory thresholds before treatment and 6 months after the end of the treatment doesn't show any significant difference between the 2 groups (p > 0.05). Impairment of the audition superior to 20 dB HL was observed in 8.5% of the patients of each group. The auditive results are similar in the 2 groups. CONCLUSION: These two methods of treatment can not be strictly compared due to several bias in this study. Indeed more patients were treated by VN with a longer follow-up and only the patients with a class C or D audition according to the criteria of the AAO-HNS could be treated by CL. The VN provides a better control of the vertigos than the CL which is an efficient method of treatment in invalidating Meniere's disease. In all the cases, the quality of the results on vertigos depends on the degree of hypovalence after treatment. The auditive results are similar. Since the results of the two treatments are similar, the simplicity of CL encourages us to broaden the indications and to modify the place of the VN in the therapeutic algorithm of Menière's disease.

Adult↗
PubMed2005

[The outcome of treatments for carcinoma of the external auditory canal].

OBJECTIVE: A retrospective analysis of management and survival of patients treated for temporal bone carcinoma. PATIENTS AND METHODS: Thirty patients underwent treatment for carcinoma of the temporal bone. Twenty-five squamous cell carcinomas, 1 melanoma, 2 basocellular carcinomas and 2 adenoid cystic carcinomas were treated. Thirteen patients were treated before for the same disease. RESULTS: Staging revealed 12 T1 and T2, 6 T3 and 12 T4 tumours. The mean follow up was 5 years (2-276 months). The Kaplan Meier survival curves showed survival rates at 2 years of 82%, 67% and 32%, and at 5 years of 82%, 67% and 17%, respectively for the stages T1 or T2, T3 and T4. At the end of follow up at 9 years the survival rates were 66%, 66% and 17% for the stages T1 or T2, T3 and T4 respectively. Overall stages a complete remission was found in 65% and 23%, and deceased was 35% and 77%, respectively for the primary treatment group and the salvage surgery group. CONCLUSION: Long-term prognosis of the carcinoma of the external auditory canal mainly depends on the stage and primary treatment. Surgery (lateral temporal bone or subtotal temporal bone resection, both in combination with a neck dissection and a parotidectomy) and adjuvant radiotherapy is the treatment of choice for part of stage T1 and all T2 and T3 tumours. The improved survival (65%) of patients treated de novo compared with those treated with salvage surgery (23%) suggests that early referral and aggressive primary surgical treatment with postoperative radiotherapy offer the greatest chance of cure.

Adult↗
PubMed2005

[Skull vibratory test in partial vestibular lesions--influence of the stimulus frequency on the nystagmus direction].

INTRODUCTION: Results of the skull vibratory test (SVT) in partial unilateral vestibular peripheral lesions (PUVL) are different from the results in total vestibular lesions (TUVL). AIM: To reveal a correlation between the results of the analysis of the skull vibratory nystagmus (SVN) horizontal component and the side of the lesion; to correlate these results with the stimulus frequency. To find out a predictive correlation between the SVN horizontal and vertical components and the topography of a vestibular lesion. To appreciate the degree of vestibular deafferentation (extended to high frequencies) provoked by gentamicin labyrinthectomy and its efficiency in Meniere's disease. PATIENTS AND METHODS: 53 patients with a SVN and a PUVL were included and compared with 10 TUVL and 10 normal subjects. Protocol included a HST (2 Hz), a SVT at 30, 60 and 100 Hz and a caloric test. Recordings were performed with a 2D and 3D VNG device. RESULTS: In PUVL, SVN at 30, 60 and 100 Hz was obtained in 80, 90 and 90% of cases respectively. SVN is correlated with the side of the lesion at 30, 60 and 100 Hz respectively in 65%, 63%, 80% of cases. SVN is not correlated with the side of the lesion in 20% of Meniere's disease, in 8% of vestibular neuritis and in 6% of vestibular schwannoma. In PUVL HSN is correlated with the side of the lesion in 69% of cases. The direction of the HSN and of the SVN was different in 23% when the nystagmus attended at the same time for both tests. In PUVL the direction of the SVN is different at 100 Hz and 30 Hz in 16% of cases when they are concomittant on the same patient. After Gentamicine labyrinthectomy, the coherence of the results in caloric test, HSN and SVN (areflexy and lesional nystagmus beating toward the safe side) was correlated with the efficiency of the therapy. A SVN vertical component was met in 10% of PUVL (essentially in anterior canal dehiscence and few cases of partial labyrinthitis). The horizontal SVN SPV is significantly slower in PUVL than in TUVL patients (p=0.0004). CONCLUSIONS: The SVT is a vestibular global and rapid test which explores high frequencies. In PUVL the direction of SVN is not always predictive of the side of the lesion and is sometimes depending on the stimulus frequency, the state of the vestibular lesion, the vestibular structure concerned (1/2 circular canals or otolithic organs) and the kind of sensory cells implicated in the lesion. In TUVL The direction of the SVN is always coherent with the side of the lesion (this is useful to predict the efficiency of a Gentamicine Labyrinthectomy). A SVN vertical component can mean a lesion of the vertical canal in PUVL.

Adolescent↗
PubMed2004

[Vibratory test and head shaking test and caloric test: a series of 87 patients].

OBJECTIVES: The purpose of this work was to study the complementary contribution of the vibratory test (VT), the head shaking test (HST) and the caloric test (CT) in patients with total or partial vestibular lesions. We investigated the usefulness of these three tests, particularly the high frequency VT, for multiple-frequency vestibular study. MATERIALS AND METHODS: The study cohort included 40 patients with total vestibular lesions (TVL) and 47 patients with partial vestibular lesions (PVL), the latter group including 21 patients with recent Menière disease, 15 with sudden-onset loss of vestibular function (SLVF), 5 with tumors of the cerebropontine angle, and six with diverse conditions. The HST protocol was 2 Hz stimulation (head speed greater than 180 degrees /s). The VT used an ABC 100 Hz vibrator operating at 0.8 mm and an S stimulator delivering frequencies between 30 and 115 Hz during 10 s stimulations. An LIVN-2 videoscope (biodigital France) and a 2D and 3D videonystagmograph (synapsis France) were used for the recordings. Mastoid stimulation was used for the VT. RESULTS: For the 40 patients with TVL, the three tests (VT, CT, HST) were in agreement for all frequencies. The nystagmus produced by the VT demonstrated a horizontal component in 96% of the patients, a vertical component in 47%, and a rotational component in 30%. For the 47 patients with PVL, 9 of the 21 with Menière disease had a normal CT. Conversely, nystagmus was triggered by the HST in 10 and by the VT in 6. Nystagmus triggered by the VT and the HST was non-coherent with opposing direction in two-thirds of the patients. In certain cases, the VT demonstrated a variation in the direction of the nystagmus depending on the stimulation frequency, 30 or 100 Hz. Among the 15 patients with SLVF, the HST triggered nystagmus in only 5 and the VT in 14 (5 patients had nystagmus non-coherent with the side of the lesion). For the 5 patients with tumors of the cerebropontine angle (small neuroma or meningioma), the CT was negative in all 5, the HST was negative in 3, and the VT demonstrated lesional nystagmus in 4. Looking at the overall results, in the 47 patients with PVL (including 21 cases of Menière disease outside an acute phase) the CT demonstrated significant hypovalence in 70%, while the nystagmus demonstrated asymmetrical response in 44% when triggered by the HST and in 85% when triggered by the VT. CONCLUSION: The VT is less invasive than the HST, particularly for elderly patients with osteoarthritis. It would be interesting in patients with bilateral tympanic perforation since the CT cannot be performed. It can reveal vestibular asymmetry. For unilateral partial vestibular lesions, the VT triggers nystagmus more often than the HST. It is particularly sensitive between acute episodes in patients with Menière disease. A discordance between the direction of the nystagmus triggered by the HST and the VT is particularly frequent in patients with labyrinthine hydropsis who exibit a normal CT. In certain cases of apparent bilateral areflexia to the CT for low frequencies, the VT can disclose vestibular asymmetry for high frequencies. The nystagmus triggered by the VT begins and ends with stimulation with little or no tiring. The nystagmus triggered by the HST occurs after the stimulation and depends on the frequency of the head shaking. Thus, the HST (2 Hz and its harmonics), the VT (100 Hz) and the CT (<0.01 Hz) all make significant contributions to multiple-frequency analysis of vestibular function, particularly useful in patients with partial vestibular lesions. These tests probably solicit cells with different topographies or different frequency sensitivities.

Aged↗
PubMed2004

[Cavernous haemangiomas: hearing and vestibular inaugural symptoms].

INTRODUCTION: Cavernous haemangiomas (cavernomas)(CH) are relatively rare (2% of cranial tumoral pathology) vascular malformations mostly observed in the central nervous system. Their most common topographical site in brain stem is midline in the pons, for which clinical course may mimic symptoms of peripheral origin (sudden deafness, fluctuating hearing loss, Meniere-like vertigo). AIM: To establish the correlation between the clinical manifestations of hearing and balance disturbance and the anatomical site within the pons of cavernous haemangiomas, and to describe their clinical features, and the findings on auditory brainstem response (ABR) and magnetic resonance imaging (MRI). To propose a literature review about CH and its implications. MATERIAL AND METHOD: We made a retrospective review of the histories of three patients aged 24, 44 and 45 years, diagnosed as having cavernomas of the brainstem in which audiometric evaluation, videonystagmography (VNG), ABR and imaging techniques lead to the diagnosis of intracranial cavernoma. RESULTS: The clinical and radiological files were reviewed and a direct relationship between symptoms and localization was found in all 3 patients, especially in relation to our understanding of the auditory and vestibular pathways within the brainstem. CONCLUSION: The literature regarding cavernomas of the pons is reviewed and the clinical, neuroimage, pathological, natural course and management aspects of the disease are discussed. We recommend the use of cerebral MRI for initial diagnosis which shows a typical rosette-like appearance with a heterogeneous signal on T2-weighted images, along with follow-up and investigation into similar profiles among family members. At present there is no consensus about the treatment to follow when cavernomas are located in the brain stem. There is no specific medical treatment for this condition, and surgery is indicated only exceptionally. Anticoagulant therapy, platelet-dispersing medication and violent sports activities are contraindicated.

Adult↗
PubMed2004

[Failure rate and revision surgery in ossiculoplasty with Kurz titanium prosthesis].

UNLABELLED: Despite its excellent biocompatibility, failures and in particular extrusion of the prosthesis have been described in ossiculoplasty with titanium prosthesis. OBJECTIVE: Report our experience with revision ossicular recontruction in ossiculoplasty with Kurz prosthesis. Identify causes of failure in ossiculoplasty using the titanium prosthesis. MATERIAL AND METHODS: Retrospective chart reviews were performed for 110 patients who had undergone titanium ossicular implants between November 1998 and 2002. All patients had undergone ossiculoplasty using titanium middle ear implants. Patients were divided into 2 groups: in group 1 patients underwent revision ossiculoplasty; in group 2 patients had a successful surgery at first stage. Anatomic and functional results have been studied in these two groups. Causes of failures were analysed. RESULTS: The overall failure rate was 20% (22/110). Twenty patients underwent revision ossiculoplasty. Nine primary failures were attributable to a short implant. Two extrusions were observed. At long term billow-up, the functional gain between the primary and revision ossiculoplasty was comparable. CONCLUSION: Revision ossiculoplasty is worthwhile for those patients who have failure of the titanium prosthesis in ossiculoplasty. A large cartilage graft interposition is necessary to prevent extrusion. The overall luxation rate observed in our series was mainly due to a too short prosthesis and we recommend now a reconstruction with longer prosthesis.

Adult↗
PubMed2003

[Nystagmus and vibration test research of mechanisms, theoretical methods: on 52 cases of unilateral vestibular lesions].

OBJECTIVE: The aim of the present study was to examine the characteristics of the Vibratory Nystagmus (VN) optimise the topography and the frequency of the stimulus, determine the origin of the VN and analyse its clinical implications. MATERIAL AND METHOD: 52 severe unilateral vestibular lesions (SUVL) (post-surgical vestibular areflexy) were studied. The vibratory nystagmus was measured by 2D and 3D videonystagmography (Synapsis, France). The stimulus was applied with a 3S vibrator at the vertex, both mastoïds, and posterior cervical muscles at frequencies ranging from 20 to 150 Hz. For topographic optimisation, stimulation was given with S vibrator (Synapsis, France) at 100 Hz. The interferences between the vibratory test (VT) and the caloric test (CT) were studied on the normal ear (in 11 subjects). The same study was carried with the optokinetic test. RESULTS: The VT revealed a defective nystagmus at all frequencies of stimulation. Optimal response was obtained in a band frequency of 80-120 Hz. Stimulations at 100 Hz showed optimal responses for mastoïd topography (responses in 96% of the cases). Stimulation at the posterior cervical muscles and at the vertex indicated respectively a response in 90% and 60% of the cases. The efficiency of the mastoïd stimulation is not correlated with the side of stimulation (p = 0.9). The interference between the VT and caloric test (CT) at cold water (30 degrees et 20 degrees C) exhibited the inversion of the caloric nystagmus during the vibrator stimulation. The resulting nystagmus is respectively an algebric subtraction or addition between the pre-existing caloric nystagmus and the value of the vibratory nystagmus obtained before caloric test. Adaptation of the VN is moderate. The interference between the VT and the optokinetic test resulted in a subtraction or addition effect, according to the side of the lesion and the direction of the optokinetic stimulus. CONCLUSION: The VT is an efficient stimulation in mastoïd topography. The vestibular contribution is bilateral by bony conduction of the vibration, it explores frequencies ranging from 30 to 120 Hz, with a maximum of response at 100 Hz. The VT interacts with the caloric test and the optokinetic test. The stimulation is very strong, and is able to inverse the caloric nystagmus at cold water stimulation (20 degrees C). In labyrinthine-defective subjects, the VN is always defective at all frequencies, whatever is the topographic location of the stimulus, and the position of the head.

Caloric Tests↗
PubMed2003

Time-intensity trade of bilaterally bone-conducted sounds in normal hearing subjects.

OBJECTIVE AND METHODS: 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 60 dBHL in 30 normal-hearing subjects using a centering method. Time-intensity trading functions were obtained by means of a sound image shifted towards one side by presenting an ITD, and shifted back to a centered sound image by varying the IID in the same ear. ITD values were varied from -600 to +600 microseconds at 200 microseconds steps, where negative values indicate delays to the right ear. RESULTS: Time-intensity trading functions in response to bone-conducted signals showed significantly lower discrimination thresholds across IIDs, when compared to a control group with applied air-conducted signals. These findings can be interpreted as a constructive interference effect related to the intimate mechanism of bilateral bone conduction, where interaural time differences play a major role. CONCLUSION: Time-intensity trade of bilaterally bone-conducted sounds in normal-hearing subjects is the highly sensitive. The high speed of sound through the skull may be the main reason for the high sensitivity of time-intensity trading.

Adult↗
PubMed2003

[Nystagmus and vibratory test: evidence for mechanism. Material conditions and methods in the fast detection of unilateral vestibular lesions].

OBJECTIVE: The aim of the present study was to examine the characteristics of vibratory nystagmus (VN), optimise the topography and the frequency of the stimulus, determine the origin of the VN and analyze its clinical implications. MATERIAL AND METHOD: Fifty-two severe unilateral vestibular lesions (SUVL) (post-surgical vestibular areflexy) were studied. The vibratory nystagmus was measured by 2D and 3D videonystagmography (Synapsis, France). The stimulus was applied with a 3S vibrator at the vertex, both mastoïds, and posterior cervical muscles, at frequencies ranging from 20 to 150 Hz. For topographic optimization, stimulation was given with S vibrator (Synapsis, France) at 100 Hz. The interferences between the vibratory test (VT) and the caloric test (CT) were studied on the normal ear (in 11 subjects). The same study was carried out with the optokinetic test. RESULTS: The VT revealed a defective nystagmus at all frequencies of stimulation. Optimal response was obtained in a band frequency of 80-120 Hz. Stimulations at 100 Hz showed optimal responses for mastoid topography (responses in 96% of the cases). Stimulation at the posterior cervical muscles and at the vertex indicated respectively a response in 90% and 60% of the cases. The efficiency of the mastoid stimulation was not correlated with the side of stimulation (p=0.9). The interference between the VT and caloric test (CT) with cold water (30 degrees C and 20 degrees C) exhibited the inversion of the caloric nystagmus during the vibrator stimulation. The resulting nystagmus was respectively an algebraic subtraction or addition between the pre-existing caloric nystagmus and the value of the vibratory nystagmus obtained before the caloric test. Adaptation of the VN was moderate. The interference between the VT and the optokinetic test resulted in a subtraction or addition effect, according to the side of the lesion and the direction of the optokinetic stimulus. CONCLUSION: The VT is an efficient stimulation in mastoid topography. The vestibular contribution is bilateral by bony conduction of the vibration, it explores frequencies ranging from 30 to 120 Hz, with a maximum of response at 100 Hz. The VT interacts with the caloric test and the optokinetic test. The stimulation is very strong, and is able to inverse the caloric nystagmus at cold water stimulation (20 degrees C) In labyrinthine-defective subjects, the VN is always defective at all frequencies, whatever the topographic location of the stimulus, and the position of the head.

Follow-Up Studies↗
PubMed2002

[Surgical strategy in paranasal sinus mucoceles].

INTRODUCTION: The aim of this retrospective study is to describe the surgical management of paranasal sinus mucoceles. MATERIALS & METHODS: In the period from 1981 through 2000, 45 patients were treated for symptomatic mucoceles. The mucoceles were most frequently found in the anterior ethmoidofrontal system. 13 patients were operated via a bicoronal transfrontal extradural approach. A complete marsupialization under endonasal endoscopic control was performed in 21 cases. Eleven patients were operated via a trans-facial approach. RESULTS: The follow up period was 4.7 years (2 to 15 years) on average for endonasal approaches and 11 years on average (2 to 20 years) for the other approaches. All patients were free of complaints immediately after the operation. Nine cases were lost to follow-up. Cysts recurred in 5 patients. CONCLUSION: We recommend an endoscopic approach to the treatment of mucoceles as the surgical procedure of choice. In high and lateral extended frontal mucoceles, a trans-frontal extradural approach is still recommended. Long term follow-up is necessary to obtain an accurate assessment of the results.

Adolescent↗