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1.
Rev Mal Respir ; 36(2): 179-190, 2019 Feb.
Article in French | MEDLINE | ID: mdl-30429093

ABSTRACT

INTRODUCTION: This paper reports the French data from a post-hoc analysis of the international IDEAL study, which aimed to describe a recent cohort of patients with severe asthma, the impact of the disease on quality of life, as well as the population of patients eligible for treatment with omalizumab, mepolizumab and reslizumab. METHODS: Eligible patients were≥12 years of age, with severe asthma (GINA steps 4 and 5). RESULTS: A total of 129 patients were included in this post-hoc analysis. Their mean age was 53 years, the majority were overweight, they were mainly women (64%) and had at least one medical comorbidity (85%). More than half had suffered from asthma for more than 25 years and were non-smokers. Lung function was moderately impaired. Blood eosinophil count was≥150 cells/µL in 66% of patients,≥300 cells/µL in 34% of patients, and≥500 cells/µL in 12% of patients. One out of three patients was currently treated with omalizumab and 24% had maintenance oral corticosteroids. Asthma was poorly controlled with a negative impact on quality of life (ACQ≥1.5) in 67% of patients. In this population 40% of patients were eligible for omalizumab, 27% for mepolizumab and 2% for reslizumab. CONCLUSIONS: These findings show that a considerable proportion of patients with severe asthma remain uncontrolled and are not eligible for any of the available biological treatments. This underlines the need for therapeutic innovations in this disease.


Subject(s)
Anti-Asthmatic Agents/therapeutic use , Antibodies, Monoclonal, Humanized/therapeutic use , Asthma/drug therapy , Asthma/epidemiology , Omalizumab/therapeutic use , Adolescent , Adult , Aged , Aged, 80 and over , Asthma/pathology , Child , Cohort Studies , Comorbidity , Female , France/epidemiology , Humans , Male , Middle Aged , Quality of Life , Severity of Illness Index , Treatment Outcome , Young Adult
2.
Allergy ; 71(9): 1335-44, 2016 09.
Article in English | MEDLINE | ID: mdl-27087007

ABSTRACT

BACKGROUND: We performed post hoc analyses to evaluate the effect of humanized monoclonal antibody mepolizumab in patients with severe eosinophilic asthma previously treated with omalizumab. METHODS: Data were collected from two randomized double-blind, placebo-controlled studies: MENSA (NCT01691521: 32-week treatment phase) and SIRIUS (NCT01691508: 24-week treatment phase). Active treatment was 75 mg intravenous mepolizumab (MENSA) or 100 mg subcutaneous mepolizumab (MENSA, SIRIUS). Patients had evidence of eosinophilic inflammation ≥150 cells/µl (at screening) or ≥300 cells/µl (during the previous year). Primary outcomes were the rate of exacerbations (MENSA) and the percentage reduction in oral corticosteroid (OCS) dose (SIRIUS). Other outcomes included lung function (forced expiratory volume in 1 s and morning peak expiratory flow), Asthma Control Questionnaire (ACQ-5), St George's Respiratory Questionnaire (SGRQ) scores, and safety. RESULTS: Overall, 576 patients were included from MENSA and 135 from SIRIUS, with 13% and 33% previously receiving omalizumab, respectively. In MENSA, mepolizumab reduced the rate of exacerbations by 57% (prior omalizumab) and 47% (no prior omalizumab) vs placebo. In SIRIUS, reductions in OCS use were comparable regardless of prior omalizumab use. Despite reducing chronic OCS use, mepolizumab also resulted in similar reductions in exacerbation rate relative to placebo in both subgroups. Asthma control and quality of life improved with mepolizumab vs placebo in both studies independent of prior omalizumab use, as shown by ACQ-5 and SGRQ scores. Adverse events were also comparable irrespective of prior omalizumab use. CONCLUSIONS: These post hoc analyses indicate that patients with severe eosinophilic asthma respond positively to mepolizumab regardless of prior use of omalizumab.


Subject(s)
Anti-Asthmatic Agents/therapeutic use , Antibodies, Monoclonal, Humanized/therapeutic use , Asthma/diagnosis , Asthma/drug therapy , Eosinophilia/pathology , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Leukocyte Count , Male , Middle Aged , Omalizumab/therapeutic use , Randomized Controlled Trials as Topic , Respiratory Function Tests , Retreatment , Severity of Illness Index , Treatment Outcome , Young Adult
3.
Ear Hear ; 29(6): 947-56, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18941410

ABSTRACT

OBJECTIVE: Evaluating the effect of anxiety and depression on clinical measures of general health, tinnitus-specific quality of life, and coping abilities. DESIGN: Two hundred sixty-five chronic, subjective tinnitus sufferers were divided into four psychological symptom groups according to cut-off scores on anxiety and depression subscales of the Hospital Anxiety and Depression Scale: (1) no-symptoms, (2) anxiety-only, (3) depression-only, and (4) anxiety-plus-depression. General health-related quality of life (SF-36), tinnitus-specific quality of life (tinnitus reaction questionnaire and tinnitus handicap inventory), and coping abilities (tinnitus coping style questionnaire) were assessed and analyzed across these four psychological symptom groups, which did not differ on age, gender, marital, and working status. RESULTS: Statistically significant and clinically relevant differences on general health-related and tinnitus-specific quality of life and coping abilities were identified when comparing anxiety-plus-depression subgroup with the subgroups anxiety-only, depression-only, or no-symptoms. Highest associations were seen between the anxiety-plus-depression subgroup and impaired quality of life and maladaptive coping. CONCLUSIONS: Our results demonstrate the additive effect of both anxiety and depression in impairing general health-related and tinnitus-specific quality of life and application of coping strategies, and reiterate the need for investigating both symptoms in the clinical evaluation of tinnitus patients.


Subject(s)
Adaptation, Psychological , Anxiety/complications , Depression/complications , Tinnitus/complications , Tinnitus/psychology , Adult , Affective Symptoms , Aged , Female , Health Status , Humans , Logistic Models , Male , Middle Aged , Multivariate Analysis , Quality of Life , Surveys and Questionnaires
4.
Eur Arch Otorhinolaryngol ; 265(3): 287-92, 2008 Mar.
Article in English | MEDLINE | ID: mdl-17901968

ABSTRACT

During and after an increase of inner ear pressure, induced by injection of artificial perilymph, the 2f1 - f2 and f2 - f1 distortion products (DPs) in cochlear microphonics (CM) and otoacoustic emissions (OAE) were recorded in the guinea pig. An inner pressure increase of approximately 600 Pa gave only small changes in CMDP and DPOAE. Along with a decrease in f1 amplitude, a small decrease in amplitude of the 2f1 - f2 and a small increase in the f2 - f1 were measured in CM. This matches a shift from a symmetrical position of the operating point for hair cell transduction, leading to an increase in even-order distortion and a decrease in odd-order distortion. Similar, a decrease in 2f1 - f2 DPOAE was expected. This might be the case at the generation sites but this effect was then more than compensated for by a better middle ear transfer, accounting for the increase of 0.4 dB of the 2f1 - f2 DPOAE amplitude. In conclusion, changes of overall inner ear fluid pressure have minor effects on cochlear function. This is a relevant finding for further understanding of diseases with changed inner ear fluid volumes, as Ménière's.


Subject(s)
Cochlear Microphonic Potentials , Ear, Inner , Otoacoustic Emissions, Spontaneous , Animals , Guinea Pigs , Pressure
5.
Stereotact Funct Neurosurg ; 85(4): 150-7, 2007.
Article in English | MEDLINE | ID: mdl-17259751

ABSTRACT

OBJECTIVE: Long-term evaluation of treatment of chronic, therapeutically refractory tinnitus by means of chronic electrical stimulation of the vestibulocochlear nerve. PATIENTS: Inclusion criteria were severe, chronic, therapeutically refractory, unilateral tinnitus and severe hearing loss at the ipsilateral site. Out of 6 patients, 4 patients were selected for long-term evaluation. Two patients were not evaluated because of premature dropout. MATERIAL AND METHODS: A stimulation electrode was placed around the vestibulocochlear nerve through a retrosigmoid approach and connected to a subcutaneously positioned pulse generator via an extension cable. Follow-up was performed 3 months and 42.5 months after implantation. Three measures for treatment outcome were used. First, effect sizes were determined by means of the total Tinnitus Handicap Inventory (THI) score using Cohen's formula. Second, general and tinnitus-specific audiometric tests were performed in on and off conditions of the neurostimulation system. Third, recordings were noted for tinnitus severity and treatment success on a visual analogue scale. RESULTS: All 4 patients reported successful treatment with neurostimulation. The effect size after 3 months was 0.7, indicating an average effect, while the effect size measured during long-term follow-up was 1.75, indicating a substantial effect with major clinical implications. No changes in hearing level for both ears were measured. The neurostimulation system did not change the tinnitus pitch in any of the patients, and resulted in a minimal reduction of tinnitus loudness in only 2 patients. In all 4 patients the original tinnitus sound was replaced by another, pleasantly perceived sound. The average VAS score of perceived tinnitus severity was reduced from 8 to 3.25. The average VAS score for treatment success was 7.25. CONCLUSIONS: The long-term follow-up of neurostimulation treatment for chronic tinnitus shows promising results. Long-term results were better than those determined after a 3-month follow-up. In all patients the tinnitus was replaced by another sound, which was perceived as pleasant. Further studies are needed before accepting neurostimulation as a treatment modality for chronic, therapeutically refractory tinnitus.


Subject(s)
Brain/physiology , Electric Stimulation Therapy/methods , Tinnitus/therapy , Chronic Disease , Cochlear Nerve , Electric Stimulation Therapy/instrumentation , Electrodes , Female , Follow-Up Studies , Humans , Longitudinal Studies , Male , Middle Aged , Pain Measurement , Pilot Projects , Prostheses and Implants , Severity of Illness Index , Tinnitus/physiopathology , Vestibular Nerve
6.
Acta Otolaryngol ; 126(12): 1236-44, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17101583

ABSTRACT

In the last few decades functional neuroimaging tools have emerged to study the function of the human brain in vivo. These techniques have increased the knowledge of how the brain processes stimuli of different sensory modalities, including auditory processing. Positron emission tomography (PET) has been used for nearly 20 years to study changes in cerebral blood flow associated with auditory stimulation in normal and hearing impaired subjects. PET studies gave insight into the neural base of processing basic sound features such as frequency and intensity, but complex stimuli such as speech and music have also been investigated extensively. Knowledge of the normal auditory function of the brain helps us to understand the neural base of hearing deficits and provides ideas for possible treatments. Although functional magnetic resonance imaging (fMRI) is replacing PET in many neuroimaging studies nowadays, PET still holds unique advantages and can give us valuable knowledge about the auditory cortex and auditory perception.


Subject(s)
Acoustic Stimulation , Auditory Cortex/physiology , Positron-Emission Tomography , Auditory Cortex/diagnostic imaging , Humans
7.
Int J Audiol ; 45(9): 496-502, 2006 Sep.
Article in English | MEDLINE | ID: mdl-17005492

ABSTRACT

The objective of this study was to evaluate daily stressors, coping, personality, physical and mental health, and quality of life in Menière patients. 110 consecutive patients with definite Menière's disease were assessed using the Dutch Daily Hassles List, Coping Inventory for Stressful Situations (CISS), Symptoms Checklist 90 (SCL-90), NEO Five Factor Inventory (NEO-FFI), General Health Questionnaire (GHQ-12), and the Short Form Health Survey 36 (SF-36). Duration and subjective severity of symptoms were scored using a self-report questionnaire. It was shown that Menière patients had more daily stressors, used certain coping strategies less often, and had more psychopathology (e.g. anxiety and depression), and a worse quality of life compared to healthy reference groups. No abnormalities in personality were found. Patients with more severe symptoms had more psychopathology and a worse quality of life than patients with mild symptoms. The psychological profile of Menière patients seems comparable to patients with other chronic diseases. The outcomes should be used to intensify psychological support in patients with this disabling disease.


Subject(s)
Adaptation, Psychological , Meniere Disease/psychology , Quality of Life , Case-Control Studies , Female , Health Status , Humans , Male , Meniere Disease/diagnosis , Middle Aged , Personality , Sickness Impact Profile , Surveys and Questionnaires
8.
Acta Otolaryngol ; 126(10): 1030-5, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16923705

ABSTRACT

CONCLUSION: The changes in cochlear function during a destructive acute endolymphatic hydrops were relatively small. This might be consistent with the hypothesis that an endolymphatic hydrops is a marker of disordered inner ear homeostasis rather than the cause of the clinical symptoms of Ménière's disease. OBJECTIVE: Assessment of cochlear function during induction of a destructive acute endolymphatic hydrops. MATERIALS AND METHODS: During repetitive microinjections of 0.5 microl of artificial endolymph at a rate of 50 nl/s the 2f1-f2 and f2-f1 cochlear microphonics distortion products (CMDP) and 2f1-f2 distortion products otoacoustic emissions (DPOAE) were recorded in the guinea pig. RESULTS: A 'catastrophe' occurred in the inner ear when 2.5-3.5 microl of artificial endolymph was injected. A rupture of Reissner's membrane was then found, most often in the apical turn of the cochlea. This rupture had only minor effects on the endocochlear potential, whereas it caused a marked decrease in 2f1-f2 DPOAE amplitude. The 2f1-f2 and f2-f1 CMDP amplitude increased during each injection prior to the rupture. After the rupture the f2-f1 CMDP amplitude decreased during each injection, possibly due to a shift of the cochlear transducer operating point position.


Subject(s)
Cochlear Duct/injuries , Endolymphatic Hydrops/physiopathology , Meniere Disease/etiology , Meniere Disease/physiopathology , Animals , Cochlea/physiopathology , Cochlear Microphonic Potentials/physiology , Disease Models, Animal , Endolymph/physiology , Endolymphatic Hydrops/etiology , Guinea Pigs , Microinjections , Otoacoustic Emissions, Spontaneous/physiology , Pressure , Rupture
9.
Eur Arch Otorhinolaryngol ; 263(5): 430-4, 2006 May.
Article in English | MEDLINE | ID: mdl-16380806

ABSTRACT

An acute endolymphatic hydrops was induced by the injection of 1.1 mul of artificial endolymph into the scala media of guinea pig cochleas. This volume corresponds with an acute endolymphatic hydrops of 23%. During and after the injection, cochlear function was assessed by measuring the 2f(1)-f(2 )and f(2)-f(1) distortion products in cochlear microphonics (CMDP) and the 2f(1)-f(2) distortion product otoacoustic emission (DPOAE). A reversible pressure increase of 23 Pa and a relatively stable endocochlear potential (EP) were accompanied by a mean decrease in 2f(1)-f(2) DPOAE of only 3.4 dB. Similarly, the 2f(1)-f(2) CMDP amplitude change was minimal during and after the injection. The only substantial change was measured in the f(2)-f(1) CMDP amplitude. The measured range of distortion amplitudes during an acute endolymphatic hydrops can be related to small changes in the cochlear transducer operating point.


Subject(s)
Cochlear Microphonic Potentials/physiology , Endolymphatic Hydrops/physiopathology , Otoacoustic Emissions, Spontaneous/physiology , Acute Disease , Animals , Audiometry, Evoked Response , Disease Models, Animal , Guinea Pigs , Meniere Disease
10.
Hear Res ; 209(1-2): 19-23, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16039079

ABSTRACT

The round window membrane and cochlear aqueduct complex in the guinea pig are reconstructed with 3D-imaging, using orthogonal plane fluorescence optical sectioning (OPFOS). The 3D-images show that the periotic duct and the aqueduct are connected to a pouch-like extension of the round window. The function of this may be regulation of aqueduct flow resistance under the influence of a pressure difference between inner ear fluid and middle ear.


Subject(s)
Cochlear Aqueduct/anatomy & histology , Guinea Pigs/anatomy & histology , Imaging, Three-Dimensional/instrumentation , Round Window, Ear/anatomy & histology , Animals , Female , Imaging, Three-Dimensional/methods
11.
Otol Neurotol ; 26(3): 425-8; discussion 428, 2005 May.
Article in English | MEDLINE | ID: mdl-15891644

ABSTRACT

BACKGROUND: Tinnitus is an uncomfortable symptom for the patient and an embarrassing one for the consulted physician. So far, there is no treatment that can be considered well established in terms of providing long-term reduction of tinnitus in excess of placebo effects. There is considerable evidence of pathophysiological similarity between tinnitus and chronic pain. Some forms of chronic pain can be treated by neurostimulation. OBJECTIVE: This study was designed to investigate the feasibility of neurostimulation of the cochlear nerve in order to reduce tinnitus. STUDY DESIGN: Pilot study. SETTING: Tertiary referral center. PATIENTS: Five patients with therapeutically refractory tinnitus were selected for this study. INTERVENTION: Placing a stimulation lead around the cochlear nerve through the suboccipital approach and connecting the stimulation lead to a pulse generator. MAIN OUTCOME MEASURES: The patients experienced 1) an absence of major or minor complications, such as death, meningitis, cranial nerve deficit, and vestibular problems; 2) tolerance of the procedure as considered by the patient; 3) relief of tinnitus in at least one patient. RESULTS: Implantation of the neurostimulation system was accomplished in each patient without any difficulty. None of the patients considered the treatment unbearable. No major or minor complications occurred in this study. Subjective tinnitus reduction was accomplished in four patients. CONCLUSION: Our preliminary data show that neurostimulation of the cochlear nerve is feasible, is bearable for the patient, and is a safe treatment modality without major complications. The effects on tinnitus are promising.


Subject(s)
Cochlear Nerve , Electric Stimulation Therapy , Tinnitus/physiopathology , Tinnitus/therapy , Aged , Cochlear Nerve/physiopathology , Electrodes, Implanted , Feasibility Studies , Humans , Middle Aged , Pilot Projects , Severity of Illness Index , Treatment Outcome
12.
Hear Res ; 202(1-2): 180-7, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15811710

ABSTRACT

The role of the endolymphatic sac (ES) in endolymph volume homeostasis is speculative. The present study investigates changes of the ES's epithelia and luminal filling after induction of an acute endolymphatic hydrops. After microinjection of 1.1 mul artificial endolymph into scala media of the cochlea, guinea pigs were terminated immediately (n = 6) or after different time intervals ; 1/2 h (n = 3), 1 h (n = 4) and 2 h (n = 4). Inner ear specimens were processed for light and/or transmission electron microscopy. The non-injected contralateral ear served as a histological control. Correct injection was confirmed by detection of microspheres in the endolymphatic compartment after the same microinjection procedure. In all specimens, ribosome rich cells and intraluminal macrophages appeared to be actively involved in degradation of homogeneous substance (HS) by secreting lytic enzymes and digestion, respectively. Amazingly, in our study no ES differences were found between injected and non-injected ears and no distinct changes were observed in guinea pigs terminated after different time intervals. The ES's luminal HS was always present and often to a large extent. This is in contrast with [Hear. Res. 138, 81] dramatic changes were observed. Endolymph volume homeostasis is a complex mechanism, in which the role of HS remains obscure.


Subject(s)
Endolymphatic Hydrops/pathology , Endolymphatic Sac/pathology , Acute Disease , Animals , Cochlear Duct , Endolymph , Endolymphatic Hydrops/etiology , Female , Guinea Pigs , Microinjections , Microscopy, Electron , Microspheres , Time Factors
13.
Pneumologie ; 58(12): 837-44, 2004 Dec.
Article in German | MEDLINE | ID: mdl-15597250

ABSTRACT

The present cost-of-illness study is focused on the costs of COPD in Germany. In a pre-study, data on 814 randomly selected patients were collected to achieve reliable figures for the distribution of COPD severity grades and the frequencies of exacerbations. The main study was performed on 321 randomly selected patients from the pre-study. Data on resource use were collected in a face-to-face interview with the respective physicians using the patient records as a basis. Costs associated with resource consumption were weighted with the frequencies of COPD severity grades as assessed in the pre-study to determine the costs of COPD. Annual COPD-related costs per patient were 3,027 from the societal perspective. Main cost components were hospitalisations (26 %), medication (23 %) and early retirement (17 %). Annual COPD-related costs from the perspective of the German health insurance system (GKV) were 1,944 euros per patient.


Subject(s)
Pulmonary Disease, Chronic Obstructive/economics , Cost of Illness , Germany , Humans
14.
Clin Otolaryngol Allied Sci ; 29(6): 565-70, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15533137

ABSTRACT

This study investigates the test-retest distributions and the interval for true score change of the (modified) Amsterdam Inventory for Auditory Disability and Handicap [(m)AIAD], when the latter is used to measure the effect of an intervention. In a previous study the reliability and validity of the (m)AIAD in a cohort of hearing impaired patients were found to have satisfactory high values. In this prospective study, 66 patients underwent a tympanoplasty operation. Preoperatively and postoperatively pure tone audiometry was performed, and at the same time the subjective hearing ability was established by means of the (m)AIAD. The correlation between threshold change and score change was 0.35 (Pearson's r). Scores on the (m)AIAD had to change by at least 16 to be qualified as a true change. For only nine of 66 subjects this criterion was fulfilled. No clear relation exists, except for these nine subjects, between threshold change and score change in this patient population. The study also shows that disability questionnaires have their limitations, when using them to measure the result of a medical intervention in an individual patient.


Subject(s)
Disability Evaluation , Disabled Persons , Hearing Disorders/diagnosis , Surveys and Questionnaires , Adolescent , Adult , Aged , Audiometry, Pure-Tone/methods , Auditory Threshold/physiology , Female , Hearing Disorders/epidemiology , Humans , Male , Middle Aged , Postoperative Care , Preoperative Care , Prospective Studies , Reproducibility of Results , Severity of Illness Index , Tympanoplasty
15.
Acta Otolaryngol ; 124(8): 929-36, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15513529

ABSTRACT

OBJECTIVE: To determine a relation between acute inner ear pressure changes and cochlear function as measured by low-level 2f(1)-f(2) distortion product otoacoustic emissions (DPOAEs). MATERIAL AND METHODS: During and after a change in inner ear pressure induced by injection or aspiration of perilymph, the 2f(1)-f(2) DPOAE at 4.5 kHz generated by low-level primaries was recorded in the guinea pig. RESULTS: Large changes in overall inner ear pressure produced only small changes in the 2f(1)-f(2) amplitude and phase. During injection of 0.5 microl of artificial perilymph into the scala tympani over a 10-s period, the mean inner ear pressure increased by approximately 500 Pa, with an accompanying mean increase in the 2f(1)-f(2) amplitude of 0.7 dB. During aspiration of 0.5 microl of perilymph over a 10-s period, the mean inner ear pressure decreased by approximately 700 Pa, with an accompanying mean decrease in the 2f(1)-f(2) amplitude of 0.9 dB. Changes in DPOAE amplitude followed inner ear pressure changes with a delay of 1-2 s. The magnitude and sign of the amplitude changes can (partly) be explained by a change in oval window stiffness. No explanation was found for the measured delay. CONCLUSION: Clinically, these experiments can be of value in gaining insight into the pathophysiological mechanisms of pathological pressure changes as seen in Meniere's disease and perilymphatic fistulae.


Subject(s)
Ear, Inner/physiology , Meniere Disease/physiopathology , Otoacoustic Emissions, Spontaneous/physiology , Perilymph/physiology , Animals , Cochlear Aqueduct/physiology , Female , Guinea Pigs , Pressure
16.
J Assoc Res Otolaryngol ; 5(4): 404-10, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15682510

ABSTRACT

The resistance for fluid flow of the cochlear aqueduct was measured in guinea pigs for different positions of the round window membrane. These different positions were obtained by applying different constant pressures to the middle ear cavity. Fluid flow through the aqueduct was induced by small pressure steps superimposed on these constant pressures. It was found that the resistance for fluid flow through the aqueduct depended on the round window position but not on flow direction. The results can be explained by special fibrous structures that connect the round window with the entrance of the aqueduct. It was also found that the equilibrium inner ear pressure depends on middle ear pressure, indicating that the aqueduct does not connect the inner ear with a cavity with constant pressure.


Subject(s)
Cochlear Aqueduct/physiology , Labyrinthine Fluids/physiology , Models, Biological , Round Window, Ear/physiology , Animals , Guinea Pigs , Pressure
17.
Acta Otolaryngol ; 123(4): 547-51, 2003 May.
Article in English | MEDLINE | ID: mdl-12797592

ABSTRACT

OBJECTIVE: This study investigates the effect of regular airflow, as an isolated single factor, through Groningen and Provox2 voice prostheses on biofilm formation. MATERIAL AND METHODS: Groningen and Provox2 voice prostheses were placed in a modified Robbins device and inoculated with the total microflora from an explanted Groningen voice prosthesis. After 3 days, prostheses were either flushed 3 times per day with the Provox flush, treated with an airflow using an increasing order of air pressure (10, 15 and 20 cmH2O) or vigorously perfused by means of imitated coughing (air pressure 20 cmH2O). As a control, prostheses were left undisturbed to promote biofilm growth. Following flushing, blowing or coughing, each artificial throat was perfused with 200 ml of phosphate-buffered saline. This procedure was repeated three times a day for 9 days. At the end of each day, the artificial throats were filled with growth medium for 30 min and left empty during the night after draining. After 12 days the microflora on each voice prosthesis was quantified by plating on blood agar for bacteria and on de Man, Rogosa and Sharpe agar for yeasts. RESULTS: The use of the Provox flush reduced bacterial prevalence on Groningen and Provox2 voice prostheses to 71% and 45% of the control values, respectively, without affecting the number of yeasts. Increasing airflows and imitated coughing yielded reductions of 45-70% in bacterial and yeast prevalence on Provox2 voice prostheses. On the Groningen voice prostheses the effects of increasing airflows and imitated coughing were less pronounced: reductions in bacterial and yeast prevalence of 56-87% were observed. CONCLUSION: This study shows that use of the Provox flush has a cleansing effect, especially on Provox2 voice prostheses, and furthermore suggests that daily airflow through voice prostheses as part of a daily maintenance scheme reduces biofilm formation and can be expected to prolong the life of these devices.


Subject(s)
Biofilms , Cough , Larynx, Artificial , Therapeutic Irrigation , Air , Biofilms/growth & development , Humans , In Vitro Techniques , Water
18.
Eur Arch Otorhinolaryngol ; 260(1): 9-11, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12520349

ABSTRACT

We analysed the fluid pressure in the perilymphatic and endolymphatic spaces of the cochlea in eight guinea pigs after endolymphatic hydrops (EH) was surgically created. The control experiments were done in the opposite ears. EH was histologically confirmed after the conclusion of the pressure measurements. No statistically significant pressure difference between the scala media and the scala tympani was found, either in ears with EH or the control ears. However, the endocochlear potential, which we evaluated for position verification of the measurement pipette in the cochlea, was statistically significantly decreased in ears with EH.


Subject(s)
Endolymphatic Hydrops/physiopathology , Meniere Disease/physiopathology , Perilymph/physiology , Animals , Cochlea/pathology , Cochlea/physiopathology , Endolymphatic Hydrops/pathology , Female , Guinea Pigs , Meniere Disease/pathology , Pressure
19.
Article in English | MEDLINE | ID: mdl-12232468

ABSTRACT

In this study freeze fracture, low-voltage cryo-SEM, SEM and TEM were used to characterise the glycocalyx and stereociliary interconnections in the hair cell bundle of the vestibular sensory epithelia of the guinea pig. The glycocalyx resembles a shell-like structure separately surrounding each stereocilium and kinocilium over its entire length. The lateral interciliary connections emerge from the glycocalyx layer, forming an extensive extracellular network maintaining the stereocilia as a bundle. These connections are morphologically similar to the glycocalyx, and grossly oriented in the same direction, indicative of a role in the mechanical transduction system. The matrix material around the glycocalyx also appears to be morphologically similar to the glycocalyx, suggesting the glycocalyx to be even more important in the mechanical transduction system. The tip-links are covered with a layer, which is a continuation of the glycocalyx covering the stereocilia.


Subject(s)
Glycocalyx/ultrastructure , Hair Cells, Auditory/ultrastructure , Vestibule, Labyrinth/ultrastructure , Animals , Female , Freeze Fracturing , Guinea Pigs , Microscopy, Electron
20.
Acta Otolaryngol ; 122(2): 138-45, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11936904

ABSTRACT

The inner ear fluid pressure of guinea pigs was measured during square wave middle ear cavity pressure variation. Time constants were derived for the slopes of the inner ear pressure recovery curves after middle ear pressure change. A "single exponential" function did not fit well and therefore more complicated functions were used for this purpose. For middle ear pressure increasing from zero to a few centimetres of water, returning to zero again, decreasing from zero to minus a few centimetres of water and then returning to zero again, time constants for the inner ear pressure recovery curves were on average 15.0, 8.6, 2.5 and 2.5 s, respectively. The results could not be described using a linear model with constant window membrane compliance and cochlear aqueduct flow resistance. A possible explanation for the large difference in time constants for positive or negative middle ear pressure changes is a dependence on aqueduct flow resistance or round window membrane position.


Subject(s)
Ear, Inner/physiology , Ear, Middle/physiology , Animals , Cochlear Aqueduct/physiology , Female , Guinea Pigs , Labyrinthine Fluids/physiology , Pressure , Round Window, Ear/physiology , Time
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