[Neighbourhood noise pollution in housing]. / Pollution sonore de voisinage dans l'habitat.

NEIGHBOURHOOD NOISE POLLUTION IN HOUSING. The discomfort caused by environmental noise in home living space is very frequently observed in our time, its consequences are underestimated. The genesis of this nuisance lies in the poor quality of buildings, which are subject to a series of regulations and obligations that are often not respected, as well as incivism and non-compliance with Public Health Code decrees governing noise emissions from various activities. Physician practitioners or specialists are sometimes solicited by their patients on the repercussions on their health and on the action to be taken to obtain a reduction of this nuisance.

GESTION DE LA POLLUTION SONORE LIÉE AU VOISINAGE. La gêne provoquée par les bruits de l'environnement dans l'espace de vie à domicile constitue une doléance fréquente en milieu urbain. Dans la genèse de ces nuisances interviennent la mauvaise qualité des constructions soumises à une série de réglementations et d'obligations souvent non respectées, et l'incivisme et le non-respect des décrets du code de la santé publique régissant les émissions sonores de diverses activités. Les médecins ou spécialistes sollicités par leurs patients doivent en connaître les conséquences cliniques, socio-comportementales et économiques souvent sous-estimées, et la conduite à tenir pour obtenir une réduction de ces nuisances.

[Cervico-facial fascitiis. A major ENT emergency]. / Les cellulites cervico-faciales. Une grave urgence ORL.

Cervical fasciitis is one of the most severe ENT emergencies, requiring immediate management by a multidisciplinary team. Often due to a benign pharyngeal or dental infection, this life-threatening condition leads to extensive necrosis spreading along the fascia of the neck, possibly to the mediastinum. A retrospective analysis of 150 consecutive patients admitted to our institution between January 2001 and December 2006 showed:--a 7% mortality rate;--pulmonary involvement in one-third of cases and hemodynamic failure or mediastinitis in half the patients;--mechanical ventilation for an average of 10 days, intubation for 13 days, tracheostomy for 31 days, intensive care unit management for 17 days, and hospitalization for 26 days; and--functional and esthetic sequelae in about half the patients. These data underscore the extreme severity of cervicofacial fasciitis and the need to pay close attention to any general or functional signs of severe sepsis in patients with apparently mild head or neck infections. Such patients should be urgently referred to a tertiary center for immediate CT scan and surgical drainage of any cervical or thoracic abscesses. Intensive medical care is needed to manage the frequent cardio-hemodynamic failure and secondary pulmonary/mediastinal infections. The only possible predisposing factors so far identified are inadequate initial medical treatment and self-medication with nonsteroidal antiinflammatory drugs.

Mutations associated with succinate dehydrogenase D-related malignant paragangliomas.

OBJECTIVE: Hereditary paraganglioma (PGL) syndromes result from germline mutations in genes encoding subunits B, C and D of the mitochondrial enzyme succinate dehydrogenase (SDHB, SDHC and SDHD). SDHB-related PGLs are known in particular for their high malignant potential. Recently, however, malignant PGLs were also reported among a small minority of Dutch carriers of the SDHD founder mutation D92Y. The aim of the study was to investigate which SDHD mutations are associated with malignant PGL. DESIGN: Case histories; collaborative study between referral centres in France, the USA, and the Netherlands. PATIENTS: Six unrelated patients with metastatic PGLs of either sympathetic or parasympathetic origin. MEASUREMENTS: Assessment of SDHD mutations underlying malignant PGL. RESULTS: Germline SDHD mutations underlying metastatic PGL were G148D, Y114X, L85X, W43X, D92Y, and IVS2+5G-->A. CONCLUSION: Our findings indicate that malignant SDHD-related PGL is associated with several mutations besides D92Y.

Characterization of mucosal biofilms on human adenoid tissues.

OBJECTIVES: To demonstrate the presence of mucosal biofilm in adenoid tissue using double staining for visualization of both the bacterial matrix and the bacterial cells. To identify bacterial species present on the surface of the studied adenoids. STUDY DESIGN: Prospective study. METHODS: A total of 39 specimens of adenoidectomy were removed from children with chronic and/or recurrent otitis media. The specimens were prepared for light microscopy using Gram staining, scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). Double staining was performed with CLSM to visualize both the bacteria and the glycocalyx matrix. Nine adenoids on which bacterial biofilms were visualized with CLSM were used for identification of bacterial species by 16S-DNA polymerase chain reaction (PCR) amplification and homology analysis. RESULTS: Of the 39 adenoids investigated, 22 (54%) showed evidence of mucosal biofilms. Gram staining, SEM and CLSM showed the presence of bacterial cells, organized in bacterial microcolonies. CLSM with double staining demonstrated mucosal biofilms by showing the presence of both bacteria and the glycocalyx. The use of 16S-DNA polymerase chain reaction (PCR) amplification and subsequent sequence analyses identified the presence of Corynebacterium argentoratense, Streptococcus salivarius, Micrococcus luteus, and Staphylococcus aureus. CONCLUSIONS: This study demonstrates that adenoid tissue in children with chronic or/and recurrent otitis media contains mucosal biofilms in 54% of the cases. The existence of living bacteria has been demonstrated. Further studies are required to describe the panel of bacteria that can be harbored in the biofilms present in adenoids and the mechanisms involved in the physiopathology of otitis prone children.

Taste deficits after middle ear surgery for otosclerosis: taste somatosensory interactions.

The aim of this study was to evaluate the postoperative consequences of chorda tympani reclining during middle ear surgery for otosclerosis. Electrogustometric taste thresholds were measured at 11 loci on the tongue and the soft palate in 14 patients before surgery, and 8 d, 1 month and (in some cases) 6 months after surgery. A significant increase in thresholds was observed on the ipsilateral side of the tongue after surgery. The extent of the deficit and the recovery time course depended on tongue locus. The tip of the tongue displayed a limited deficit, suggesting bilateral chorda tympani innervation. The edge of the tongue was less impaired than the dorsal or the lateral tip loci; it may be dually innervated by both chorda tympani and glossopharyngeal nerves in humans, as already shown in rats. Likewise for the fungiform papillae located just anterior to the circumvallate papillae. Somatosensory early complaints suggest a derepression of chorda tympani on lingual nerve signals. In a second stage, relief of complaints before electrogustometric threshold recovery suggested trigeminal compensation of the chorda tympani deficit. Relief of complaints seems to involve central integrative processes, whereas the evolution of electrogustometric threshold represents the actual recovery time course of chorda tympani peripheral sensitivity.

[Vestibular schwannoma (acoustic neurinoma). Natural history and quality of life]. / Schwannome vestibulaire (neurinome de l'acoustique). Histoire naturelle et qualité de vie.

Management of patients with vestibular shwannomas has gradually improved with the development of stereotaxic radiotherapy, our better understanding of these tumours' natural history, and the increasing accent placed on quality of life. The aim of this study was two-fold:--to evaluate the natural history and tumor growth in a series of 386 patients presenting with small- or medium-sized tumors amenable to conservative management; and ii) to compare quality of life in 356 patients undergoing surgery (n = 198), radiosurgery (n = 23) or conservative management (n = 135). The annual tumor growth rate was < 1 mm in 58.6% of patients, 1-3 mm in 29.2%, and > 3 mm in 12.2%. The overall growth rate did not differ significantly between intrameatal and extrameatal tumors (1.02 +/- 1.8 and 1.40 +/- 3.1 mm/y, respectively). The tumor growth rate was not related to sex, age, initial hearing status or initial tumor grade. Late diagnosis was the only factor significantly associated with the tumor growth rate. All three treatment modalities had a negative impact on QOL, but surgery led to a significant deterioration. This study supports a conservative "wait-and-scan" policy for patients with small tumours, most of which are slow-growing. Long-term radiological controls are needed even for non growing tumours. Surgery significantly degrades quality of life.

Relationship between dynamic balance and self-reported handicap in patients who have unilateral peripheral vestibular loss.

OBJECTIVE: The purpose of this study was to investigate whether Dizziness Handicap Inventory (DHI) score is related to postural performance as assessed by dynamic posturography. STUDY DESIGN: Retrospective study. SETTING: Outpatient in a tertiary referral center. PATIENTS: Ninety-two complete unilateral vestibular loss patients, categorized into 3 groups according to the postlesion stage: 1 to 2 months (n = 32; age, 47.6 +/- 10.7 yr), 4 to 7 months (n= 23; 47.1 +/- 8.37 yr), and 1 year and older (n = 37; 49.2 +/- 9.5 yr). MAIN OUTCOME MEASURES: Dizziness Handicap Inventory and dynamic balance measured with a seesaw platform moving either in the anterior-posterior or in the mediolateral direction. RESULTS: The mean DHI score was 25.8 +/- 18.7 and the range was 0 to 68. Dizziness Handicap Inventory scores did not differ significantly between the different unilateral vestibular loss groups studied. No difference was detected between the groups for the 3 subscores (emotional, functional, and physical), except that the older-than-1-year group had a significantly higher physical score than the 2 others. No correlation was found between DHI scores and postural indicators for either direction of the platform. However, patients unable to maintain balance when the seesaw platform moved in the mediolateral direction had significantly higher DHI scores than those who did not fall. CONCLUSION: Even if they are not directly related, we suggest that DHI and dynamic posturography are complementary approaches for appreciating the vestibular compensation process and are thus useful for postoperative counseling for vestibular loss patients.

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.

Role of nitrogen in transmucosal gas exchange rate in the rat middle ear.

This study investigates the role of nitrogen (N2) in transmucosal gas exchange of the middle ear (ME). We used an experimental rat model to measure gas volume variations in the ME cavity at constant pressure. We disturbed the steady-state gas composition with either air or N2 to measure resulting changes in volume at ambient pressure. Changes in gas volume over time could be characterized by three phases: a primary transient increase with time (phase I), followed by a linear decrease (phase II), and then a gradual decrease (phase III). The mean slope of phase II was -0.128 microl/min (SD 0.023) in the air group (n = 10) and -0.105 microl/min (SD 0.032) in the N2 group (n = 10), but the difference was not significant (P = 0.13), which suggests that the rate of gas loss can be attributed mainly to the same steady-state partial pressure gradient of N2 reached in this phase. Furthermore, a mathematical model was developed analyzing the transmucosal N2 exchange in phase II. The model takes gas diffusion into account, predicting that, in the absence of change in mucosal blood flow rate, gas volume in the ME should show a linear decrease with time after steady-state conditions and gas composition are established. In accordance with the experimental results, the mathematical model also suggested that transmucosal gas absorption of the rat ME during steady-state conditions is governed mainly by diffusive N2 exchange between the ME gas and its mucosal blood circulation.

Aberrant internal carotid artery in the temporal bone: imaging findings and management.

OBJECTIVES: To describe the clinical and radiological features of the vascular anomaly aberrant internal carotid artery (ICA) in the temporal bone and to discuss management strategies. DESIGN: Retrospective study. PATIENTS: Sixteen cases of aberrant ICA were diagnosed between 1982 and 2003. RESULTS: Of 16 cases, 11 were recognized by imaging assessment, 4 were recognized during middle ear surgery, and 1 was recognized clinically. Among the 11 cases, 8 malformations were diagnosed because of otologic symptoms related to the abnormal ICA or chronic otitis, while the other 3 were identified incidentally because of an underlying accompanying disease. In 4 cases, the diagnosis was made during surgery related to chronic otitis media (n = 2) or conductive hearing loss (n = 2). In these 4 cases, massive bleeding resulted from surgical injury to the vessel. Packing the external auditory canal and the middle ear first controlled the bleeding. Endovascular procedure was required in 2 cases to exclude an aneurysm or to control bleeding but was followed by anterior cerebral stroke in 1 case. The aberrant ICA could be identified on computed tomographic scan by the following features: intratympanic mass, enlarged inferior tympanic canaliculus, absence of the vertical segment of the ICA canal, and absence of bone covering the tympanic portion of the ICA. Conventional angiography was mandatory when intervention was planned to control bleeding or aneurysm. CONCLUSIONS: This study highlights that aberrant ICA has to be identified before any middle ear surgery because misdiagnosis may lead to dramatic surgical complications, whereas diagnosis with computed tomographic scan is easy. Bleeding is a minor complication compared with the putative neurologic deficit due to endovascular occlusion.

Transmucosal gas-loss rates in middle ears initially filled with O2 or CO2.

This study investigates the role of different gases in clearance of gas in the middle ear cavity (ME) by its mucosal blood flow. A rat model was used to measure gas volume changes in the ME cavity at constant pressure without ventilation. We disturbed the normal gas composition of the ME by filling it with O2 or CO2, measured the consequent changes in gas volume over time and compared these results with previously obtained ones for air and N2. The first 5 min of the primary transient phase (phase I) for O2 or CO2 was characterized by a volume loss decrease of -0.49 ± 0.34 µL and -46.28 ± 8.49 µL, respectively, with volume loss increase for air and N2 differing greatly, at +0.17 ± 0.17 and +2.31 ± 0.81, respectively. The CO2 value of -46.28 µL showed that a volume of gas equivalent to that of the ME cleft volume was eliminated within the first 5 min. In the second phase (phase II), all gases showed a linear decrease in volume, which presumably represents a steady-state gas loss rate. However, the gas loss rate of -0.307 ± 0.170 µL min-1 for O2-filled MEs was significantly higher than the mean of -0.124 µL min-1 for all other gases. We used a previously established mathematical model to calculate the effective ME mucosal blood flow rate under steady-state (phase II) conditions. The blood flow results for O2-filled MEs differed greatly from those of the other gases (89.0 ± 49.28 vs. 26.5 µL min-1, on average), which suggest that the model used to calculate blood flow should be modified if used with O2-filled MEs. Further work should involve a comparison of our method with different methods to verify ME blood flow rate.

In vivo demonstration of the absorptive function of the middle ear epithelium.

The present study investigated in vivo fluid and ion transport across the middle ear epithelium. The tympanic membrane of rats was punctured under general anesthesia. A capillary tube was fitted to the external auditory canal and the bulla filled with various solutions. Middle ear (ME) fluid volume variations were then measured at constant pressure. When saline was used, a linear decrease of fluid volume was apparent. Replacement of sodium with a non-permeable cation (N-methyl-D-glucamin) reduced the absorption rate from 0.065+/-0.008 to 0.019+/-0.003 microl/min (P<0.05, n=6). Similarly, amiloride (10(-3)M), a sodium channel antagonist, reduced the absorption rate to 0.027+/-0.006 microl/min (P<0.05, n=6). Net absorption was abolished when chloride was substituted with gluconate: -0.008+/-0.004 microl/min (P<0.02, n=6), which might have been related (i) to the role of chloride as a diffusible anion through the paracellular pathway, or (ii) to the secretion of chloride through apical channels. However in this condition, 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid, a chloride channel blocker, did not affect the rate of fluid exchange -0.008+/-0.007 microl/min (P=0.75, n=6). This model provides the first in vivo evidence for the absorptive function of the ME. Fluid introduced into the ME cavity disappears due to active transport through the mucosa. This process is sodium-dependent and can be hindered by high concentration of amiloride. The rate of absorption is high enough to allow total clearance of fluid from the cavity of the middle ear within 13 h. This process might play a role in the maintaining a fluid-free and gas-filled middle ear cavity.

Are somatostatin analogs therapeutic alternatives in the management of head and neck paragangliomas?

BACKGROUND: Although mostly benign, head and neck paragangliomas require active management because of injury to adjacent neurovascular structures. Surgery, usually preceded by embolization, allows for complete tumor removal. However, surgery carries a significant risk of iatrogenic injury, related to tumor volume. Because paragangliomas express somatostatin receptors with high density, we investigated the effect of a long-acting somatostatin analogue (OCT-LAR) on the size of such tumors to reduce iatrogenic injury and related the percentage of tumor shrinkage to a tracer uptake index calculated on somatostatin receptor scintigraphy (SRS). METHODS: In eight of the first nine patients, 30 mg of OCT-LAR was given intramuscularly every 28 days for 3 doses; one patient withdrew after the first dose because of side effects. Conventional imaging with computed tomography (CT) scan or magnetic resonance imaging plus SRS revealed 18 paraganglioma sites. For each lesion, a tracer uptake index was calculated on pretreatment SRS. All 18 tumors were measured by CT scan before treatment and 1 month after the third injection. RESULTS: The average percent tumor shrinkage was 4.0 +/- 10.0%, and the average tumor reduction was 1.0 +/- 3.8 cm (P = .27, NS). Only 2 of the 18 paragangliomas shrank by more than 20%; these two tumors belonged to the only one secreting patient. There was no significant relation between tracer uptake index and tumor response. CONCLUSION: These results suggest 1) that SRS results do not predict OCT-LAR efficacy on paraganglioma size, and 2) OCT-LAR is not useful in the preoperative management of paragangliomas.

Technical pitfalls in middle ear gas studies: errors introduced by the gas permeability of tubing and additional dead space.

CONCLUSIONS: We demonstrated errors introduced by the gas permeability of the tubing and additional dead space. Materials with practically no permeability, such as glass, must be used to overcome the loss or gain of gas through the walls of tubes used for studying ME gas variations. Experiments conducted at a constant volume (variable pressure) require the smallest possible tubing volume in order to obtain good sensitivity and improve the accuracy of the results. OBJECTIVES: Experimental studies that investigate middle ear (ME) gas exchanges, using either pressure measurements or volume changes, are conducted using various tubing connections between the ME and a measuring device. The aims of this study were to highlight experimental problems due to the errors introduced by (i) the gas permeability of the tubing used and (ii) additional dead space in experiments conducted at constant volume. MATERIAL AND METHODS: The problem of the gas permeability of the tubing was addressed by comparing three types of tube (silicone, polyethylene, PVC) with a glass tube. Horizontally placed tubes were connected to a syringe filled with pure CO2 via a gas-tight valve. The end of each tube tested was plunged into colored water (5% Coomassie Brilliant Blue R-250). The tube was washed out with CO2 until gas bubbles were seen leaving it. The valve was then closed and the movement of water in the tube was observed. The same experiments were repeated for pure O2. The problem of the error introduced by the additional dead space volume was addressed at a theoretical level using the well-known gas laws. Two conditions were studied: condition A, in which the experiment was conducted at constant pressure and the volume was measured; and condition B, in which the experiment was conducted at constant volume and the pressure was measured. The main outcome measure of each condition was the calculated variation in the final number of moles of gas involved. RESULTS: No water movement was observed in glass tubes. In contrast, plastic tubes exhibited significant gas permeability effects for both CO2 and O2. The colored solution advanced at a faster rate with CO2 than O2 but differently for each type of tubing. For condition A, gas transfer was independent of the volume of the external tubing and was accurately measured by the displacement of the droplet in the lumen. In contrast, for condition B, the pressure variations were influenced by the volume of the tubing.

Sudden sensorineural hearing loss as a revealing symptom of vestibular schwannoma.

CONCLUSIONS: Sudden sensorineural hearing loss (SSHL) is a frequent symptom of vestibular schwannoma (VS), often reveals small VSs and does not exhibit specific features. Therefore, every case of SSHL should be evaluated using systematic MRI to rule out VS in order to improve hearing and preservation facial nerve function. OBJECTIVE: SSHL leads to the discovery of a VS in a small proportion of cases (2%). However, SSHL appears to be a more frequent occurrence in the history of patients with VS (3-23% in the literature), suggesting a large disparity in the evaluation of SSHL. MATERIAL AND METHODS: A total of 139 consecutive unilateral VSs operated on between 2000 and 2002 were reviewed and analyzed regarding the prevalence, clinical and audiological features of SSHL and their relation to the size of the tumor. RESULTS: SSHL was observed in 20% of cases at some point in their VS history. The characteristics of SSHL were: (i) lack of a specific audiometric pattern, except that low-tone loss was rare; and (ii) a high rate of hearing recovery (50%). Tumor size was significantly smaller in SSHL-associated VSs compared to other VSs. In the former cases, 96% involved the internal auditory canal.