Evaluation of the impact of hearing loss in adults: Validation of a quality of life questionnaire.

OBJECTIVES: The impact of hearing loss and of auditory rehabilitation (hearing aid, cochlear implant) on quality of life is a crucial issue. Commonly used questionnaires to assess quality of life in these patients (Nijmegen, APHAB, GBI) are time-consuming, difficult for patients to fill out, and show poor sensitivity to small improvements or deterioration. The objective of the present study was to validate a dedicated quality of life scale for hearing-impaired adults with or without auditory rehabilitation. MATERIAL AND METHODS: ERSA (Évaluation du Retentissement de la Surdité chez l'Adulte: Evaluation of the Impact of Hearing Loss in Adults) is a self-administered questionnaire. It is divided into 4 domains, each comprising 5 questions graded from 1 to 10. The questions are simple, and formulated so patients will answer according to how they feel at the actual time of the session. Test-retest reliability was measured in 38 patients. Internal coherence and validity against the APHAB questionnaire as gold standard and in relation to hearing performance were measured in 122 patients at auditory assessment. Sensitivity to change in hearing was measured in 36 cochlear implant patients, before and 6 or 12 months after implantation. RESULTS: Test-retest reliability was very satisfactory (ρ=0.88). Internal coherence was good for all questions. External validity, comparing ERSA to APHAB scores in the same non-implanted hearing-impaired patients, was good (ρ=0.52). Additionally, ERSA scores correlated with hearing performance in adverse conditions (monosyllabic words: ρ=0.22; sentences in noise: ρ=0.19). In patients tested before and after cochlear implantation, improvement in hearing performance in silence and in noise correlated with an improvement in ERSA score (ρ=0.37 to 0.59, depending on the test), but not to GBI score. CONCLUSION: The ERSA questionnaire is easy and quick to use, reliable, and sensitive to change in hearing performance after cochlear implantation.

[A report of three cases and review of auditory brainstem implants in children]. / Implantation auditive du tronc cérébral chez l'enfant. À propos de trois cas.

AIM OF THE STUDY: To present three pediatric cases of auditory brainstem implantation (ABI) and review literature data concerning this topic. PATIENTS: The first two children had a neurofibromatosis type II with bilateral sensorineural deafness; in both cases, the implant was inserted during the surgical removal of a vestibular schwannoma; the third patient had profound deafness due to bilateral cochlear nerve insufficiency associated with inner ear malformation. RESULTS: Two postoperative complications were observed: patient 1 had a persistent fever which required the replacement of the fat graft used to seal the translabyrinthine approach; patient 3 had a CSF leakage requiring additional surgery and lumbar external drainage. In our three patients, the numbers of active electrodes were 6/22 (Cochlear ABI 24M ABI), 11/12 (Medel Opus II ABI) and 11/12 (implant Medel), respectively. Due to additional major surgical procedures and to disappointing functional results of the ABI, patient 1 stopped wearing her implant 18 months after implantation. Nine months after surgery, patient 2 achieved open-set speech recognition and was very satisfied with the implant. Six months after implantation, patient 3 (cochlear nerve deficiency), who was 3.5 years-old at the time, clearly reacted to some environmental sounds but was not yet able to achieve speech recognition. CONCLUSIONS: ABI has now entered the list of treatments that can be proposed in pediatric profound sensorineural deafness. Its major risks of complications are CSF leakage and non-auditory side effects. Its outcomes are worse and less predictable than cochlear implants. Thus, its indications must remain restricted to cases meeting the following conditions: absence of alternative option to restore hearing, patients and parents high level of motivation and realistic expectations.

[Paradoxical cutaneous reactions associated with tocilizumab therapy]. / Réactions cutanées paradoxales sous traitement par tocilizumab.

INTRODUCTION: Tocilizumab (TCZ) is a humanized antihuman interleukin (IL)-6 receptor antibody recommended for the treatment of moderate to severe active rheumatoid arthritis, adult-onset Still disease, Castleman disease and more recently, systemic juvenile idiopathic arthritis. Like anti-TNFα, rituximab and less frequently abatacept, TCZ can induce paradoxical cutaneous eruption like psoriasis with predominantly palmoplantar presentation. CASE REPORT: We report a 47-year-old woman with psoriastic arthritis who developed under anti-TNFα therapy and later under tocilizumab a paradoxical palmoplantar eruption. CONCLUSION: The specific underlying mechanisms of this side effect are unclear but relapse of these lesions seems to be observed with certain biological agents.

Long-term outcomes and risk factors for failure with the EX-press glaucoma drainage device.

PURPOSE: To report on the long-term outcomes and risk factors for failure with the EX-PRESS shunt implanted under a scleral flap. SETTINGS: Eye Department, University of Ancona, Ancona, Italy and the Oxford Eye Center, University of Witwatersrand, Johannesburg, South Africa. METHODS: The medical records of glaucoma patients who underwent consecutive EX-PRESS implantations under a scleral flap between 2000 and 2009 were reviewed. The operations were performed by two experienced surgeons using an identical surgical technique. The potential risk factors for failure that were analysed included age, sex, race, glaucoma type, previous antiglaucoma medications, previous glaucoma surgeries, diabetes, and smoking. Complete success was defined as postoperative intraocular pressure (IOP) 5 mm Hg>IOP<18 mm Hg without antiglaucoma medications. Qualified success was defined as 5 mm Hg>IOP<18 mm Hg with or without antiglaucoma medications. RESULTS: Two hundred and forty-eight eyes of 211 consecutive patients were included. The mean IOP was reduced from 27.63 ± 8.26 mm Hg preoperatively (n=248) to 13.95 ± 2.70 mm Hg at 5 years (n=95). The mean follow-up was 3.46 ± 1.76 years. Complete and qualified success rates decreased gradually from 83% and 85% at 1 year to 57% and 63% at 5 years follow-up, respectively. The risk factors for failure were diabetes, non-Caucasian race, and previous glaucoma surgery. Complete success rates of diabetic patients and non-Caucasian patients decreased from 63% and 75% at 1 year to 42% and 40% at 5 years follow-up, respectively. CONCLUSIONS: EX-PRESS success rates decrease over time but compare favourably with trabeculectomy literature data. The main identifiable risk factors for failure are diabetes, non-Caucasian race, and previous glaucoma surgery.

Comparison of trabeculectomy and Ex-PRESS implantation in fellow eyes of the same patient: a prospective, randomised study.

PURPOSE: To compare intraocular pressure (IOP) over time after standard trabeculectomy vs Ex-PRESS implantation in patients with bilateral primary open-angle glaucoma (POAG). DESIGN: Prospective, randomised study. PATIENTS AND METHODS: This study included adult patients with bilateral POAG necessitating surgery. Each patient underwent trabeculectomy in one eye and Ex-PRESS implantation under a scleral flap in the other eye according to randomised contralateral allocations. Efficacy was assessed by IOP values and success rates (IOP threshold and/or need for topical glaucoma medication) during 30 months. Statistical analysis included Generalised Estimate Equation and Cox Survival models, and paired t-tests. RESULTS: Thirty eyes of 15 patients were studied for a mean of 23.6 months (SD, ± 6.9). At the last follow-up visit, mean pre-operative IOP decreased from 31.1 (± 14.2) to 16.2 (± 1.5) mm Hg after trabeculectomy, and from 28.1 (± 9.0) to 15.7 (± 1.8) mm Hg after Ex-PRESS implantation (P=0.001). The mean number of anti-glaucoma medicines prescribed at the last follow-up decreased from 3.7 pre-operatively (both groups) to 0.9 after trabeculectomy vs 0.3 after Ex-PRESS implantation (P=0.001). Complete success rates (5

Metformin-associated lactic acidosis following acute kidney injury. Efficacious treatment with continuous renal replacement therapy.

INTRODUCTION: Metformin is a biguanide anti-hyperglycaemic drug. Metformin-associated lactic acidosis may sometimes be life-threatening. Continuous renal replacement therapy has been suggested as a method for resolving this extremely dangerous metabolic state. We describe the history of six patients admitted to the intensive care unit over a 28-month period in pre-shock conditions because of severe lactic acidosis, attributed to metformin-associated lactic acidosis, and successfully treated. METHODS: We reviewed the charts of six patients admitted to our intensive care unit between January 2008 and May 2010. After initial assessment, all patients were treated with continuous renal replacement therapy. Admission serum lactate and creatinine levels, pH, need for ventilatory and cardiovascular support, as well as continuous renal replacement therapy details and length of stay were reviewed. RESULTS: Admission pH levels of the six patients ranged between pH 6.63 and 7.0 and their serum lactate levels ranged between 12 and 27 mmol/l; the estimated creatinine clearance ranged between 6 and 24 ml min(-1) 1.73 m(-2) . All patients required vasoactive support and five required ventilatory support. Lactate levels decreased to near zero with continuous renal replacement therapy within 7-19 h in five of the patients whose intensive care unit length of stay ranged between 1 and 5 days. One patient's length of stay reached 11 days because of pneumonia, one died from multi-organ failure and another suffered permanent neurological damage following prolonged cardiopulmonary resuscitation before continuous renal replacement therapy was administered. All other patients recovered without sequellae. CONCLUSIONS: Accurate recognition of metformin-associated lactic acidosis and prompt initiation of haemodialysis are paramount steps towards rapid recovery. Large series reports and controlled studies may better determine the optimal duration and best dialysis technique in these patients.

Dynamic psychotherapy or dialectical behavioral therapy-- which is better for borderline personality disorder?

Clinical dilemma: A 20-year-old female patient, diagnosed as suffering from borderline personality disorder, is referred to your clinic. Her disorder is characterized by unstable personal relationships, impulsivity, suicidal behavior, emotional instability and pan-anxiety. After initiation of pharmacological treatment which you have chosen, you meet with her parents who ask you which is better for their daughter dynamic-analytic psychotherapy or dialectical behavioral therapy.

Bilateral uneven cataracts in children: amblyopia management by sequential intraocular lens implantation.

PURPOSE: To report on amblyopia management of children with bilateral uneven cataracts treated by sequential intraocular lens implantation. METHODS: Children with bilateral uneven cataracts who needed bilateral cataract surgery were prospectively enrolled in Oxford Eye Center, Johannesburg, South Africa and Southwest Eye Hospital, Chong Qing, China. In the same patient, the amblyopic eye with the denser cataract underwent primary intraocular lens implantation, whereas the better eye was temporarily left aphakic as an alternative to patching. A secondary intraocular lens implantation was performed in the aphakic eye when best-corrected visual acuity in the amblyopic eye attained its best potential. RESULTS: Thirteen children were included in this non-comparative study. Average age at surgery was 3.02+/-1.87 years with an average follow-up period of 9.35+/-5.23 years. In the amblyopic eyes, 10 out of 13 (77%) had less than 20/120 best-corrected visual acuity before amblyopia treatment. The optical penalization of the dominant eye (temporary aphakia) lasted on average 8.38+/-4.05 weeks. The best-corrected visual acuity of the amblyopic eye improved to 20/50 or better in six eyes (46%), and ranged from 20/60 to 20/200 in five eyes (38%); in remaining two eyes, the best-corrected visual acuity stayed below 20/200. Best-corrected visual acuity was restored to 20/30 or better following intraocular lens implantations in 12 of the dominant eyes (92%). CONCLUSIONS: Optical penalization by temporary aphakia of the dominant eye is a convenient means for treating amblyopia in children with bilateral uneven cataracts.

Rapid fluidic exchange microsystem for recording of fast ion channel kinetics in Xenopus oocytes.

We present a new lab-on-a-chip system for electrophysiological measurements on Xenopus oocytes. Xenopus oocytes are widely used host cells in the field of pharmacological studies and drug development. We developed a novel non-invasive technique using immobilized non-devitellinized cells that replaces the traditional "two-electrode voltage-clamp" (TEVC) method. In particular, rapid fluidic exchange was implemented on-chip to allow recording of fast kinetic events of exogenous ion channels expressed in the cell membrane. Reducing fluidic exchange times of extracellular reagent solutions is a great challenge with these large millimetre-sized cells. Fluidic switching is obtained by shifting the laminar flow interface in a perfusion channel under the cell by means of integrated poly-dimethylsiloxane (PDMS) microvalves. Reagent solution exchange times down to 20 ms have been achieved. An on-chip purging system allows to perform complex pharmacological protocols, making the system suitable for screening of ion channel ligand libraries. The performance of the integrated rapid fluidic exchange system was demonstrated by investigating the self-inhibition of human epithelial sodium channels (ENaC). Our results show that the response time of this ion channel to a specific reactant is about an order of magnitude faster than could be estimated with the traditional TEVC technique.

Integrated microsystem for non-invasive electrophysiological measurements on Xenopus oocytes.

We propose a new non-invasive integrated microsystem for electrophysiological measurements on Xenopus laevis oocytes. Xenopus oocyte is a well-known expression system for various kinds of ion channels, that are potential tools in drug screening. In the traditional "Two Electrode Voltage Clamp" (TEVC) method, delicate micromanipulation is required to impale an oocyte with two microelectrodes. In our system, a non-invasive electrical access to the cytoplasm is provided by permeabilizing the cell membrane with an ionophore (e.g. nystatin). Unlike the classical patch-clamp or "macropatch" techniques, this method does not require removal of the vitelline membrane. Cell handling is significantly simplified, resulting in more robust recordings with increased throughput. Moreover, because only part of the oocyte surface is exposed to reagents, the required volume of reagent solutions could be reduced by an order of magnitude compared to the TEVC method. The fabrication process for this disposable microchip, based on poly-dimethylsiloxane (PDMS) molding and glass/PDMS bonding, is cost-efficient and simple. We tested this new microdevice by recording currents in oocytes expressing the human Epithelial Sodium Channel (hENaC) for membrane potentials between -100 and +50 mV. We recorded benzamil-sensitive currents with a large signal-to-noise ratio and we also obtained a benzamil concentration-inhibition curve displaying an inhibition constant IC(50) of about 50 nM, comparable to previously published values obtained with the TEVC technique.

[Auditory brainstem implant: indications and results]. / Implant auditif du tronc cérébral: indications et résultats.

OBJECTIVES: To summarize the indications and evaluate the Auditory Brainstem Implant (ABI) performances in neurofibromatosis type 2 (NF2) and other otologics indications, as postmeningitis ossified cochlea. MATERIAL AND METHODS: Main and first indication of ABI is NF2. Emergent indications are bilateral total ossified cochlea, vestibular schwannoma with controlateral lesions, cochlear nerve aplasia or inner ear's malformations. The pre-operative evaluation includes clinical, radiological, lipreading, and psychological status. A translabyrinthine or retrosigmoid approach is performed, depending on tumoral or not tumoral status. The auditory perception with the ABI is evaluated by testing, the words recognition in open-set lists, and the speech understanding with usual sentences. RESULTS: In NF2 patients, best results are obtained in cases of smaller vestibular schwannoma and none, or short term, auditory deprivation. Negative prognostic factors are duration of total hearing loss (>10 years), tumor size (>30 mm), difficulties in electrode array placement, complications during post-operative course and number of active electrodes (<10). In cases of postmeningitis total deafness with totally ossified cochlea, results demonstrate a good benefit reaching these obtained with cochlear implant in post-meningitis deafness. CONCLUSION: These results show a clear benefit of ABI in NF2 patients, with or without previous tumor removal, in case of small tumor with a short duration of hearing loss. In case of postmeningitis ossified cochlea, results potentially reach those of cochlear implants.

Cochlear implantation and far-advanced otosclerosis.

OBJECTIVE: To evaluate results of cochlear implantation in patients with far-advanced otosclerosis. METHODS: Sixteen patients with far-advanced otosclerosis had undergone unilateral (n = 13) or bilateral (n = 3) cochlear implantation. Surgical difficulties, incidence of complications and postoperative benefit were analyzed. RESULTS: A full electrode insertion was achieved in all patients without surgical difficulties. All patients demonstrated excellent benefit of cochlear implantation. Binaural implantation still improves speech performances, compared to unilateral implantation. In case of residual cochlear function of one nonoperated side, a stapes surgery, performed during the same surgical time as cochlear implantation, can improve speech scores and restore bilateral hearing. Facial nerve stimulation occurred only in 1 patient. CONCLUSION: Cochlear implantation is the method of choice for rehabilitation of patients with otosclerosis, presenting profound or total hearing loss. Patients obtain excellent benefit with a low rate of complications.

[What should be done when surgery fails? Congenital Glaucoma: IOP rises years after surgery]. / Que faire quand la chirurgie marche mal? Glaucome congénital : la pression remonte des années après une intervention.

The treatment for congenital glaucoma is based on surgery, initially nonpenetrating and then penetrating. To start with, a simple trabeculectomy can be augmented by a deep sclerectomy, concentrated Mitomycin C application and iridencleisis. This surgical alternative starts with an "L" shaped conjunctival flap, followed by a superficial scleral flap, then by a deep scleral flap in which bed, Mitomycin C is applied. A trabeculectomy is then performed in the deep sclerectomy. The iris is prolapsed followed by a horseshoe iridotomy in order to suture it in the deep sclerectomy. The scleral flap is tightly sutured and the anterior chamber is filled with viscelastic material. The postoperative treatment consists of topical steroids until the IOP reaches 14mmHg; by then NSAIDs are used for several weeks. If needed, a beta-blocker or acetazolamide can be used during the hypertensive period.

[Performances and complications of cochlear implant in 134 adult patients implanted since 1990]. / Performances et complications de l'implant cochléaire chez 134 patients adultes implantés depuis 1990.

OBJECTIVE: The aim of this study was to analyse performance of cochlear implants in a retrospective series of adults with postlingually in order to search for predictive factors and identify complications. METHODS: Between 1990 and 2003, 134 adult patients were implanted: 129 patients on one side and 5 patients on both sides. Hearing benefit at 6, 12, 24 and 36 months and performance at 12 months were analyzed as function of the etiology, age at implantation, lipreading and speech coding strategy. RESULTS: Compared to performances before implantation, cochlear implants provided significant and rapid improvement at 6 months (p<0.0001). The results were not correlated with age at implantation, etiology or lipreading ability before implantation. Performances were worse in patients with meningitis (p<0.01), but the percentage of improvement was similar between the different etiologies. Major complications were rare: one case of regressive postoperative facial nerve weakness. CONCLUSION: Cochlear implants provide significant and rapid improvement, with low morbidity. Results are not correlated with age at implantation, etiology or lipreading ability.

[Beneficial effect of cochlear implants in the elderly]. / Bénéfice de l'implant cochléaire chez le sujet âgé.

OBJECTIVE: To evaluate the benefit of cochlear implantation in older adults aged 60 Years and over. METHODS: Fifty-six profoundly or totally hearing-impaired patients, aged 60 Years and over, were studied retrospectively. At the end of the preoperative evaluation, 28 patients received a cochlear implant. The mean age was 66 Years and the median follow-up was 22.5 Months. Speech perception scores before and after implantation were analyzed in order to evaluate the benefit of cochlear implantation. The speech perception score before implantation was compared to that of the non-implanted patients. RESULTS: There was a significant improvement of the dissyllabic words and sentences scores after implantation. The patients who are over 70 Years performed as well as those who are younger (between 60 and 70 Years). One patient developed a postoperative vertigo due a perilymphatic fistula. There was no flap-related problems. In the non-implanted group (mean age: 68 Years), 18 patients declined the cochlear device because they thought the subjective benefit of their hearing aid was sufficient and 5 patients declined because of surgical risk. The mean age, the cause and the duration of the deafness, and the speech perception scores were similar between implanted and non-implanted patients. CONCLUSION: This study demonstrates the beneficial effect of cochlear implantation in the elderly. These results suggest that a similar benefit could have been obtained in the patients who declined surgery. An early implantation could reduce the duration of the deafness and preserve binaural sound perception allowing increased performance in older people.

[Progressive bilateral hearing loss with superficial hemosiderosis of the central nervous system: contribution of cochlear implantation]. / La surdité dans l'hémosidérose superficielle du système nerveux central. Intérêt de l'implantation cochléaire.

Two cases of progressive bilateral hearing loss associated with superficial hemosiderosis of the central nervous system are reported. This is a rare disease caused by repetitive hemorrhage in subarachnoid spaces with hemosiderin deposits on the brain surface and cranial nerves. MRI provided the etiologic diagnosis in both cases based on typical low-density signals from the brain, the brainstem, and the cerebellar surfaces on T1 and T2 sequences. In one case a fourth ventricle ependymoma, which was the probable cause of hemosiderosis, was also discovered. Based on a literature review, we discuss the pathophysiological hypotheses, the modalities for treating hearing loss including cochlear implantation despite retrocochlear sensorineural hearing loss.

Developmental regulation of heat shock protein 83 in Leishmania. 3' processing and mRNA stability control transcript abundance, and translation id directed by a determinant in the 3'-untranslated region.

Developmental gene regulation in trypanosomatids proceeds exclusively by post-transcriptional mechanisms. Stability and abundance of heat shock protein (HSP)70 and HSP83 transcripts in Leishmania increase at mammalian-like temperatures, and their translation is enhanced. Here we report that the 3'-untranslated region (UTR) of HSP83 (886 nucleotides) confers the temperature-dependent pattern of regulation on a chloramphenicol acetyltransferase (CAT) reporter transcript. We also show that the majority of the 3'-UTR sequences are required for increasing mRNA stability during heat shock. Processing of the HSP70 and HSP83 primary transcripts to poly(A)(+) mRNA was more efficient during heat shock; therefore, even when stability at 33 degrees C was reduced by deletions in the 3'-UTR, transcripts still accumulated to comparable and even higher levels. Translation of heat shock transcripts in Leishmania increases dramatically upon temperature elevation. Unlike in other eukaryotes in which the 5'-UTR confers preferential translation on heat shock transcripts, we show that translational control of HSP83 in Leishmania originates from its 3'-UTR. The 5'-UTR alone cannot induce translation during heat shock, but it has a minor contribution when combined with the HSP83 3'-UTR. We identified an element located between positions 201 and 472 of the 3'-UTR which is essential for increasing translation of the CAT-HSP83 reporter RNA at 33-37 degrees C. This region confers preferential translation during heat shock even in transcripts that were less stable. Thus, investigating the traditionally conserved heat shock response reveals that Leishmania parasites use unique pathways for translational control.

Combined effects of a nasal dilator and nasal prongs on nasal airflow resistance.

STUDY OBJECTIVES: Nasal prongs (NPs), when used to assess nasal flow, can result in dramatic increases in nasal airflow resistance (NR). The aim of this study was to investigate whether the NP-induced increases in NR could be corrected by the simultaneous use of an internal nasal dilator (ND). DESIGN: NR was estimated by posterior rhinomanometry, in the basal state (NRb), and while breathing with NP (NRp), with ND (NRd), and with both ND and NP (NRd + p). PARTICIPANTS: The study was performed in 15 healthy subjects. MEASUREMENTS AND RESULTS: NR (mean NRb [+/- SEM], 2.5 +/- 0.4 cm H(2)O/L/s) significantly decreased with ND (NRd = 1.4 +/- 0.2 cm H(2)O/L/s; p < 0.001) and significantly increased with NP (NRp = 3.8 +/- 0.8 cm H(2)O/L/s; p < 0.001). A significant logarithmic relationship was found between NRd and NRb (r(2) = 0.95; p < 0.0001), and a significant exponential relationship was found between NRp and NRb (r(2) = 0.99; p < 0.0001). While breathing with both ND and NP, NRd + p was significantly lower than NRb (1.9 +/- 1.4 cm H(2)O/L/s; p < 0.02). CONCLUSIONS: Our results demonstrate that the ND tends to slightly overcorrect the NP-induced increase in NR and suggest that, in view of the possible effects of NPs on upper airway resistance, the combination of both devices might be used for nasal airflow monitoring during nocturnal polysomnography in patients presenting with highly resistive nares.

Respiratory impedance response to continuous negative airway pressure in awake controls and OSAS.

The aim of the study was to determine whether the response of respiratory impedance (Zrs) to decreasing levels of continuous negative airway pressure (CNAP) during wakefulness, differs in controls and subjects with obstructive sleep apnoea syndrome (OSAS). Zrs was measured by the forced oscillation technique (4-32 Hz) in 15 controls and 21 patients with OSAS (apnoea/hypopnoea index >20 per sleep hour) with normal lung function, in the basal state and with application of decreasing CNAP of -5, -10, and -15 hPa. Respiratory resistance was extrapolated to 0 Hz (R0) and estimated at 16 Hz (R16) by linear regression analysis of respiratory resistive impedance versus frequency. Respiratory elastance (Ers) and inertance (Irs) were estimated by multilinear regression analysis of respiratory reactance versus frequency, and resonance frequency (RF) was determined as RF=(1/2pi)(Ers/Irs)0.5. In both groups, R0, R16, Ers and RF significantly increased as the CNAP level decreased (p <0.0001 for all). R0, Ers, and RF increased significantly more in OSAS than in controls (p < 0.01, 0.001, and 0.0001, respectively), independently of the severity of obesity. Receiver operator characteristic curves showed that the parameter which best detected OSAS was RF, with a sensitivity of 81% and 93% specificity for the 13.6 Hz cut-off point. The results of the present study suggest that the response of respiratory impedance to decreasing continuous negative airway pressure levels, might allow detection of obstructive sleep apnoea syndrome in subjects with normal lung function.