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Purpose Epiglottic collapse is a specific sleep-endoscopic finding that can prove challenging to treat in patients with obstructive sleep apnea (OSA). Its effect on mandibular advancement devices (MAD) remains largely unknown. Therefore, this study assessed whether or not epiglottic collapse affects treatment outcome with MAD. Methods Patients with diagnosed OSAD underwent drug-induced sleep endoscopy (DISE) and were treated with a titratable MAD. Two age- and gender-matched controls were selected for every subject with primary epiglottic collapse (i.e., complete closure without involvement of other upper airway structures). Treatment response was defined as a reduction in oxygen desaturation index (ODI) of >= 50% following MAD therapy. Results Of 101 patients who underwent DISE, twenty (20%) showed primary epiglottic collapse (mean [SD]: 17 men; age 49.8 [10.1]; body mass index 28.3 [2.9] kg/m(2); apnea-hypopnea index 27.0 [16.9] events/h). There were no significant differences in baseline clinical characteristics between cases and controls. MAD therapy was equally effective in patients with and without epiglottic collapse (mean [SD]; ODI with MAD, 8.7 [7.7] events/h vs. 7.8 [7.5] events/h, P = .62; Delta ODI, 53.3 [29.6]% vs. 50.6 [37.7]%, P = .82; responder status, 10/20 vs. 22/40, P = .79). Logistic regression analysis revealed no associations between epiglottic collapse and treatment outcome. Conclusion The presence of epiglottic collapse during DISE does not impair the effectiveness of MAD. Therefore, MAD therapy should be considered in patients with predominant epiglottic collapse.

In the present report, a comprehensive approach on the assessment of the lower eyelid for blepharoplasty is provided. Important items such as anatomical key areas and surgical factors are discussed. Proper management of lower eyelid deformities requires an understanding of both intrinsic and extrinsic anatomical factors resulting in the unfavorable outcome.

Assessment of pharyngeal collapse patterns by drug‐induced sleep endoscopy (DISE) is often paramount to guide clinical decision‐making in patients with obstructive sleep apnoea. Being a subjective investigation, DISE findings are prone to interindividual variation. The present study introduces the concept of an expert review panel to standardize DISE scoring. Comparing the ratings of the review panel with the original ratings revealed a substantial concordance at the level of the oropharynx and a fair to moderate concordance at the levels of the soft palate, tongue base, hypopharynx, and epiglottis. Several recommendations were made to address the observed discrepancies in DISE ratings.

Mandibular advancement device (MAD) treatment outcome for obstructive sleep apnea (OSA) is variable and patient dependent. A global, clinically applicable predictive model is lacking. Our aim was to combine characteristics obtained during drug-induced sleep endoscopy (DISE), awake nasendoscopy, and computed tomography scan-based computational fluid dynamic (CFD) measurements in one multifactorial model, to explain MAD treatment outcome. A total of 100 patients with OSA were prospectively recruited and treated with a MAD at fixed 75% protrusion. In all, 72 underwent CFD analysis, DISE, and awake nasendoscopy at baseline in a blinded fashion and completed a 3-month follow-up polysomnography with a MAD. Treatment response was defined as a reduction in the apnea-hypopnea index (AHI) of >= 50% and deterioration as an increase of >= 10% during MAD treatment. To cope with missing data, multiple imputation with predictive mean matching was used. Multivariate logistic regression, adjusting for body mass index and baseline AHI, was used to combine all potential predictor variables. The strongest impact concerning odds ratios (ORs) was present for complete concentric palatal collapse (CCCp) during DISE on deterioration (OR 28.88, 95% confidence interval [CI] 1.18-704.35; p = 0.0391), followed by a C-shape versus an oval shape of the soft palate during wakefulness (OR 8.54, 95% CI 1.09-67.23; p = 0.0416) and tongue base collapse during DISE on response (OR 3.29, 95% CI 1.02-10.64; p = 0.0464). Both logistic regression models exhibited excellent and fair predictive accuracy. Our findings suggest DISE to be the most robust examination associated with MAD treatment outcome, with tongue base collapse as a predictor for successful MAD treatment and CCCp as an adverse DISE phenotype.

Background The first edition of the European position paper (EPP) on drug-induced sleep endoscopy (DISE) was published in 2014 with the aim to standardise the procedure, to provide an in-depth insight into the main aspects of this technique and to have a basis for future research. Since 2014, new studies have been published concerning new sedative agents or new insights into the pattern/levels of the obstruction depending on the depth of sedation. Therefore, an enlarged group of European experts in the field of sleep breathing disorders (SBD), including the most of the first DISE EPP main authors, has decided to publish an update of the European position paper on DISE, in order to include new evidence and to find a common language useful for reporting the findings of this endoscopic evaluation in adult population affected by SBD. Methods The authors have evaluated all the available evidence reported in the literature and have compared experience among various departments in leading European centres in order to provide an update regarding the standardisation of the DISE procedure and an in-depth insight into the main aspects of this technique. Results After the first European Position Consensus Meeting on DISE and its update, consensus was confirmed for indications, required preliminary examinations, where to perform DISE, technical equipment required, staffing, local anaesthesia, nasal decongestion, other medications, patient positioning, basics and special diagnostic manoeuvres, drugs and observation windows. So far, no consensus could be reached on a scoring and classification system. However, regarding this aim, the idea of an essential classification, such as VOTE with the possibility of its graded implementation of information and descriptions, seems to be the best way to reach a universal consensus on DISE classification at this stage. A common DISE language is mandatory, and attempts to come to a generally accepted system should be pursued.

Obstructive sleep apnea (OSA) is a very common disorder with important day and nighttime symptoms and long-term effects on health. Different treatment modalities such as positive airway pressure (PAP), oral appliance therapy using custom-made, titratable mandibular advancement devices (MAD), different types of surgery and positional therapy have been introduced over the years, with patient preference and adherence to therapy being key elements in improving treatment outcomes. Several patient selection tools to improve treatment outcomes have been introduced and evaluated over the years. Drug-induced sleep endoscopy (DISE) is a procedure that provides real-time upper airway evaluation of the sites of flutter and upper airway collapse. This review focuses on the indications and contraindications for DISE, methods of sedation and evaluation, add-on maneuvers, and the results on patient selection and treatment outcomes. A PICO approach was used to clarify the aims of this review. DISE has the advantage of being easily accessible in most ENT practices and being 3-dimensional, dynamic, site specific, safe and it is valuable in selecting patients for upper airway surgery and oral appliance therapy. There is a strong interest for further standardization and exploration of the predictive value of this evolving technique.

STUDY OBJECTIVES: The variable efficacy of mandibular advancement device (MAD) treatment necessitates both accessible and accurate methods for patient selection. However, the role of awake nasopharyngoscopy for this purpose remains dubious. We introduced an assessment method based on anatomical upper airway features during tidal breathing for nasopharyngoscopy. The current study aimed to relate these features to MAD treatment outcome. METHODS: One hundred patients diagnosed with obstructive sleep apnea were prospectively recruited for MAD treatment in a fixed 75% degree of maximal protrusion. Nasopharyngoscopic observations during Müller’s maneuver and tidal breathing were recorded both with and without MAD. Treatment outcome, confirmed by 3-month follow-up polysomnography with MAD, was classified as (1) apnea-hypopnea index reduction ≥ 50%, (2) treatment apnea-hypopnea index < 5 events/h, and (3) ≥ 10% increase in apnea-hypopnea index compared with baseline (treatment deterioration). RESULTS: A complete dataset was obtained in 65 patients. After adjusting for baseline apnea-hypopnea index, body mass index, and supine dependency, the position of the soft palate (odds ratio, 4.0; 95% confidence interval, 1.3–11.8; P = .013) and crowding of the oropharynx (odds ratio, 7.7; 95% confidence interval, 1.4–41.4; P = .017) were related to treatment deterioration. Addition of both features significantly (P = .031) improved the accuracy of baseline models based on clinical measurements alone. Moreover, with the MAD in situ, a posteriorly located soft palate (odds ratio, 9.8; 95% confidence interval, 1.7–56.3; P = .010) and a posteriorly located tongue base (odds ratio, 7.4; 95% confidence interval, 1.5–35.9; P = .013) were associated with treatment deterioration. CONCLUSIONS: Awake nasopharyngoscopy might be a valuable office-based examination to exclude the risk of treatment deterioration and improve patient selection for MAD treatment. CLINICAL TRIAL REGISTRATION: Registry: ClinicalTrials.gov; Name: Predicting Therapeutic Outcome of Mandibular Advancement Device Treatment in Obstructive Sleep Apnea (PROMAD); URL: https://clinicaltrials.gov/ct2/show/NCT01532050; Identifier: NCT01532050. CITATION: Van de Perck E, Op de Beeck S, Dieltjens M, et al. The relationship between specific nasopharyngoscopic features and treatment deterioration with mandibular advancement devices: a prospective study. J Clin Sleep Med. 2020;16(7):1189–1198.

Mandibular advancement device (MAD) outcome varies between patients. We hypothesized that upper airway collapse sites, patterns, and degrees assessed during baseline drug-induced sleep endoscopy (DISE) affect MAD outcome.One hundred patients with obstructive sleep apnea (OSA) were included and underwent baseline type 1 polysomnography. MAD was fitted intraorally at fixed 75% maximal protrusion. A total of 72 patients completed 3-month follow-up polysomnography and baseline DISE. Response was defined as apnea-hypopnea index (AHI) reduction ≥ 50%, deterioration as AHI increases during MAD treatment compared to baseline.Adjusting for baseline AHI and body mass index, patients with tongue base collapse showed 3.69 higher odds (1.27-10.73; P = .0128) for response. Complete concentric collapse at the level of the palate (5.32 [1.21-23.28]; P = .0234) and complete laterolateral oropharyngeal collapse (6.62 [1.14-38.34]; P = .0330) related to deterioration. Results for tongue base collapse and complete concentric collapse at the level of the palate were confirmed in the moderate to severe OSA subgroup. Applying these results to this selected subgroup increased response rate with 54% and decreased deterioration rate with 53%. These results were confirmed using other response and deterioration definitions.Three baseline DISE phenotypes identified during drug-induced sleep were significantly related to MAD treatment outcome: one beneficial, tongue base collapse, and two adverse, complete concentric collapse at the level of the palate and complete laterolateral oropharyngeal collapse. If confirmed in future prospective studies, these results could guide patient selection for MAD outcome.This prospective clinical trial (PROMAD) was registered on Clinicaltrials.gov with identifier: NCT01532050.Op de Beeck S, Dieltjens M, Verbruggen AE, Vroegop AV, Wouters K, Hamans E, Willemen M, Verbraecken J, De Backer WA, Van de Heyning PH, Braem MJ, Vanderveken OM. Phenotypic labelling using drug-induced sleep endoscopy improves patient selection for mandibular advancement device outcome: a prospective study. J Clin Sleep Med. 2019;15(8):1089-1099.

Although an increasing number of beneficial microbiome members are characterized for the human gut and vagina, beneficial microbes are underexplored for the human upper respiratory tract (URT). In this study, we demonstrate that taxa from the beneficial Lactobacillus genus complex are more prevalent in the healthy URT than in patients with chronic rhinosinusitis (CRS). Several URT-specific isolates are cultured, characterized, and further explored for their genetic and functional properties related to adaptation to the URT. Catalase genes are found in the identified lactobacilli, which is a unique feature within this mostly facultative anaerobic genus. Moreover, one of our isolated strains, Lactobacillus casei AMBR2, contains fimbriae that enable strong adherence to URT epithelium, inhibit the growth and virulence of several URT pathogens, and successfully colonize nasal epithelium of healthy volunteers. This study thus demonstrates that specific lactobacilli are adapted to the URT and could have a beneficial keystone function in this habitat. De Boeck et al. show that lactobacilli are decreased in patients with chronic rhinosinusitis and enriched in healthy controls. They isolate one strain adapted to the nasopharyngeal mucosa that shows beneficial probiotic effects and safety in the form of a nasal spray in healthy volunteers.

Study Objectives: Oral appliances have gained their place in the treatment of obstructive sleep apnea (OSA) where custom-made titratable mandibular advancement devices (OAm) have become the oral appliance of choice. Retrospective studies assessing possible predictors of treatment outcome with OAm have been published but are lacking uniformity in their conclusions. The PRedicting therapeutic Outcome of Mandibular Advancement Device treatment in OSA (PROMAD) study aims at identifying predictive screening methods for treatment success with OAm, assessing the following upper airway (UA) evaluation methods: awake nasendoscopy including Müller manoeuvre, and drug-induced sedation endoscopy (DISE) will identify the level, degree, and pattern of UA collapse; while computed tomography (CT)-scan based computational fluid dynamics (CFD) will evaluate changes in UA volume and resistance. Methods: PROMAD is a prospective, single-center cohort study that enrolled 100 consecutive patients with diagnosed OSA (5 events/h < apnea-hypopnea index (AHI) < 50 events/h) to be treated with a custom-made titratable OAm. Primary endpoints are the positive and negative predictive values of awake nasendoscopy including Müller manoeuvre, DISE, and CFD with and without the OAm, toward reduction in AHI. Univariate and multivariate analyses will be performed to determine which of the investigations and/or combinations thereof predict success. Conclusions: PROMAD is a prospective trial to investigate the predictive potential of awake nasendoscopy including Müller manoeuvre, DISE, and CFD, and any combination thereof in the prediction of reduction of AHI with OAm in OSA patients. The results will allow translating the assessments into optimal OSA patient selection, leading to evidence-based decision making and targeted OAm treatment.

While an increasing number of beneficial microbiome members is characterized for the human gut and vagina, beneficial microbes are underexplored for the human upper respiratory tract (URT). In this study, we demonstrate that taxa from the beneficial Lactobacillus genus might have a role as keystone species in the healthy URT. Several URT-specific Lactobacillus isolates were cultured, characterized, and further explored for their genetic and functional properties related to adaptation to the URT. Catalase genes were found in the identified Lactobacillus taxa, which is a unique feature within this mostly facultative anaerobic genus. Moreover, one of our isolated strains, Lactobacillus casei AMBR2, contained unique fimbriae enabling strong adherence to URT epithelium, inhibited the growth and virulence of several URT pathogens, and successfully colonized nasal epithelium of healthy volunteers. This study thus demonstrates that specific Lactobacillus taxa are adapted to the URT and could have a beneficial keystone function in this habitat.

Background The amount of mandibular protrusion is a key factor in optimizing the efficacy of mandibular advancement device (MAD) therapy in an individual patient diagnosed with obstructive sleep apnea. This process is called titration and is generally based on resolution of subjective symptoms like snoring and/or daytime sleepiness as a function of protrusion. An objective approach uses a remotely controlled mandibular positioner (RCMP) during a full-night polysomnography (PSG), in analogy with continuous positive airway pressure (CPAP) titration. More recently, the feasibility of RCMP use during drug-induced sleep endoscopy (DISE) titration was reported. Methods This randomized crossover trial will compare DISE-assisted titration to PSG-guided titration, as well as with the conventional subjective titration method. The primary outcome is the actual mandibular protrusive position found to be the most optimal for each tested titration procedure. Furthermore, the therapeutic efficacy will be compared among the different titration modalities using level 1 sleep studies. Discussion Currently, the optimal titration of MAD therapy is most often based on ‘trial and error’. The conventional method relies on subjective improvement in symptoms, although this may not provide the most accurate indicator for efficient titration. Therefore, relying on objective criteria in the titration process should be advantageous. In analogy with CPAP, titration of the most optimal mandibular protrusion could be performed using RCMP during an overnight titration PSG. Recently, it was shown that titration under direct visualization of upper airway patency and collapsibility is feasible using the RCMP during DISE. However, no clinical results for such a procedure are as yet available. This study is the first to compare the most optimal mandibular protrusive position according to three titration procedures, as well as to compare the therapeutic efficacy of these titration methods. Trial registration ClinicalTrials.gov, NCT03716648. Registered on 23 October 2018.

Objectives/Hypothesis To describe upper airway (UA) collapse patterns during drug-induced sleep endoscopy (DISE) in a large cohort of patients with sleep-disordered breathing (SDB) and to assess associations with anthropometric and polysomnographic parameters. Study Design Observational study. Methods A total of 1,249 patients [age 47 ± 10 y; apnea–hypopnea index (AHI) 18.9 ± 15.3/h; body mass index (BMI) 27.2 ± 3.7 kg/m2] underwent polysomnography and DISE. DISE findings were categorized to the following UA levels: palate, oropharynx, tongue base, and hypopharynx. The degree of collapse was reported as complete, partial, or none. The pattern of the obstruction was described as anteroposterior, lateral, or concentric. Associations between DISE findings and anthropometric and polysomnographic parameters were analyzed. Results Palatal collapse was seen most frequently (81%). Multilevel collapse was noted in 68.2% of all patients. The most frequently observed multilevel collapse pattern was a combination of palatal and tongue base collapse (25.5%). Palatal collapse was seen most frequently (81%). The prevalence of complete collapse, multilevel collapse, and hypopharyngeal collapse increased with increasing severity of obstructive sleep apnea (OSA). Multilevel and complete collapse were more prevalent in obese patients and in those with more severe OSA. Both higher BMI and AHI values were associated with a higher probability of complete concentric palatal collapse. Conclusion The current study provides an overview of UA collapse patterns in a large cohort of SDB patients who underwent DISE. The associations found in this study may indicate that UA collapse patterns observed during DISE cannot be fully explained by selected baseline polysomnographic and anthropometric characteristics. Level of Evidence 4. Laryngoscope, 124:797–802, 2014

Background Assessment of the overall therapeutic effectiveness of oral appliance therapy can only be realized through objectively measured compliance. The aims of this study were to assess objectively measured compliance during oral appliance therapy at 1-year follow-up and to compare these data with self-reported use. Methods Fifty-one eligible patients were enrolled in this 1-year prospective clinical study (men, 61%; mean age, 49 ± 10 years; apnea-hypopnea index, 18.0 ± 11.9 events/h sleep; BMI, 26.6 ± 4.1 kg/m2). Objective compliance during oral appliance therapy at 1-year follow-up was assessed with a microsensor thermometer. Subjective compliance was assessed by self-report. Patients with a mean objectively measured use of ≥ 4 h/night on 70% of nights monitored were considered regular users. The mean disease alleviation was calculated as a measure of overall therapeutic effectiveness. Results High agreement between objective and subjective compliance data at 1-year follow-up was reported (intraclass correlation coefficient, 0.8; 95% CI, 0.5–0.9), showing a mean subjective overestimation of 30 min (95% CI, −3.1 to 1.9; P = .02). The discontinuation rate at 1-year follow-up was 9.8%. The objective mean use rate was 6.4 ± 1.7 h/night at 1-year follow-up in continuing users, with a regular use rate of 83%. The mean disease alleviation was 54.9%. Conclusions This study is the first to our knowledge to report the 1-year results of objectively measured compliance during oral appliance therapy. In addition, a high agreement between objective and subjective compliance data were reported, with a mean subjective overestimation of 30 min. Trial registry ClinicalTrials.gov ; No.: NCT01284881; URL: www.clinicaltrials.gov

Study Objective: To determine variations in interobserver and intraobserver agreement of drug-induced sleep endoscopy (DISE) in a cohort of experienced versus nonexperienced ear, nose, and throat (ENT) surgeons. Design: Prospective, blinded agreement study. Setting: Ninety-seven ENT surgeons (90 nonexperienced with DISE; seven experienced) observed six different DISE videos and were asked to score the upper airway (UA) level (palate, oropharynx, tongue base, hypopharynx, epiglottis), direction (anteroposterior, concentric, lateral), and degree of collapse (none; partial or complete collapse). Findings were collected and analyzed, determining interobserver and intraobserver agreement [overall agreement (OA), specific agreement (SA)] and kappa values per UA level. Measurement and Results: In the nonexperienced group, overall interobserver agreement on presence of tongue base collapse (OA = 0.63; kappa = 0.33) was followed by the agreement on epiglottis (OA = 0.57; kappa = 0.23) and oropharynx collapse (OA = 0.45; kappa = 0.09). Low overall interobserver agreement in this group was found for hypopharyngeal collapse (OA = 0.33; kappa = 0.08). A similar ranking was found for degree of collapse. For direction of collapse, high interobserver agreement was found for the palate (OA = 0.57; kappa = 0.16). Among the experienced observers, overall interobserver agreement was highest for presence of tongue base collapse (OA = 0.93; kappa = 0.71), followed by collapse of the palate (OA = 0.80; kappa = 0.51). In this group, lowest agreement was also found for hypopharyngeal collapse (OA = 0.47; kappa = 0.03). Interob-server agreement on direction of collapse was highest for epiglottis collapse (OA = 0.97; kappa = 0.97). Concerning the degree of collapse, highest agreement was found for degree of oropharyngeal collapse (OA = 0.82; kappa = 0.66). Among the experienced observers a statistically significant higher interobserver agreement was obtained for presence, direction, and degree of oropharyngeal collapse, as well as for presence of tongue base collapse and degree of epiglottis collapse. Among the nonexperienced observers, high intraobserver agreement was found in particular for tongue base and epiglottis collapse. Among the experienced observers, high agreement was found for all levels but to a lesser extent for hypopharyngeal collapse. Intraobserver agreement was statistically significantly higher in the experienced group, for all UA levels expect for the hypopharynx. Conclusion: This study indicates that both interobserver and intraobserver agreement was higher in experienced versus nonexperienced ENT surgeons. Agreement ranged from poor to excellent in both groups. The current results suggest that experience in performing DISE is necessary to obtain reliable observations.

The aim of this study was to assess the value of drug-induced sleep endoscopy (DISE) using a custom-made simulation bite in maximal comfortable protrusion (MCP) of the mandible, in the prediction of treatment outcome for obstructive sleep apnoea (OSA) with a mandibular advancement device (MAD). Two hundred patients (74% male; age 46 ± 9 years; apnoeahypopnoea index [AHI] 19 ± 13 h−1 sleep; body mass index [BMI] 27 ± 4 kg m−2) with sleep-disordered breathing underwent DISE with a simulation bite in MCP. One hundred and thirty-five patients with an established diagnosis of OSA commenced MAD treatment. The associations between the findings during DISE with simulation bite and treatment outcome were evaluated. Treatment response was defined as a reduction in AHI following MAD treatment of ≥ 50% compared to baseline. Overall MAD treatment response in the studied population was 69%. The results of this study demonstrated a statistically significant association between a positive effect of the simulation bite on the upper airway patency during DISE and treatment response with MAD (P < 0.01). The results of this study suggest that the use of a simulation bite in maximal comfortable protrusion (MCP) of the mandible, as used during DISE in patients with OSA, tends to be effective in predicting treatment response of MAD treatment.

Nasal obstruction due to inferior turbinate hypertrophy is a common complaint. Radiofrequency-induced thermotherapy of the inferior turbinates (RFITT) under local anesthesia is now a widely used treatment, however reports of assessment of the long-term self-reported benefits and patient satisfaction of the treatment are scarce. This study focuses on the self-reported long-term effects of treatment and experience of RFITT. A questionnaire was sent to 441 patients who underwent RFITT in our clinic to treat symptoms of impaired nasal passage due to enlarged inferior turbinates. All patients had enlarged inferior turbinates on nasal examination. Patients were included if RFITT was done under local anaesthesia, was performed more than a year before the questionnaire was forwarded and on the indication-significant nasal obstruction because of enlarged inferior turbinates. Improvement of nasal breathing (by means of a Visual Analog Scale, VAS), changes in use of nasal spray (VAS), usage of pain medication, patient friendliness of the treatment, complaints reported after treatment, permanent effect of treatment during day and night time and willingness to recommend treatment to others were analyzed. No significant post-operative complications were observed. There was a significant reduction in use of nasal spray and the majority of patients interviewed reported long-term positive effects of RFITT during the daytime. This study shows that RFITT performed under local anesthesia is a valuable, minimally invasive, patient-friendly and well-tolerated treatment in patients with impaired nasal passage due to inferior turbinate hypertrophy.

Background It is still subject to controversy if an increased vertical opening (VO) is beneficial in oral appliance therapy for the treatment of obstructive sleep apnoea. Each oral appliance has a given thickness causing VO. Therefore, evaluation of the effects of the amount of VO on pharyngeal dimensions is mandatory. Methods The effects of VO on the cross-sectional area of the upper airway at the level of the tongue base during sleep endoscopy were scored and categorised. Results The figures demonstrate the possible effects of VO on pharyngeal collapse relative to the baseline cross-sectional area and the maximal comfortable protrusion of the mandible. Thirty-two patients (80%) showed an adverse effect of VO ( Fig. 1 ), one patient (2.5%) had a positive effect ( Fig. 2 ), and seven patients (17.5%) demonstrated an indifferent effect ( Fig. 3 ). Conclusion Based on literature, the effect of VO on pharyngeal collapse is unclear and the therapeutic impact of VO is not determined. The results of the present study indicate that the effect of VO on the degree of pharyngeal collapse as assessed during sleep endoscopy tends to be adverse, causing an increase in collapsibility in the majority of patients.

Prediction of treatment outcome is crucial for all OSA treatment modalities, as this may prevent unnecessary costs and “trial and error” treatment choices. This is an important item of the clinical reality involving OSA patients. With this in mind, the crucial question that still remains unanswered is: Can the effect of positional therapy be predicted from the (baseline) sleep study? What treatment outcome is to be expected in which patient? What is the predictive value of the baseline non-supine AHI? This item is subject to different theories and hypotheses and will be discussed in the following paragraphs.

Oral appliance (OA) therapy is a non-invasive treatment option for patients with obstructive sleep apnea (OSA). The most common type of OA therapy prescribed for the treatment of OSA is an oral appliance worn intraorally at night in order to reduce upper airway collapse by protruding the mandible (OAm). In this chapter, we will focus on the effect of supine-dependent OSA (sdOSA) on treatment outcome during OAm therapy, the prevalence of sdOSA before and under OAm therapy and the effect of combination of an OAm and positional therapy. Retrospective analyses of clinical, physiological and polysomnographic variables were performed in literature in order to identify predictors of treatment success with OA therapy. Six studies assessed a significant association between the efficacy of OAm therapy and the presence of sdOSA, whereas the results of two other studies couldnt confirm this finding. In order to evaluate the treatment effect of OAm therapy among patients with or without sdOSA, it can be important to determine the prevalence of sdOSA in the patient population starting OAm therapy. In this restricted patient group, the prevalence of sdOSA at baseline ranged from 27 to 80 %. In addition, up to one third of patients undergoing OAm therapy have sdOSA under OAm therapy. Those patients could probably benefit from additional therapy with a supine-avoidance device. Two studies assessed the efficacy of OA therapy combined with positional therapy showing promising results for this specific combination therapy.

Purpose Obstructive sleep apnea (OSA) is characterized by repetitive upper airway collapse during sleep, leading to decreased oxygen blood levels and arousal from sleep. The gold standard treatment option for moderate to severe OSA is considered continuous positive airway pressure (CPAP). In case primary treatment with CPAP fails, a reevaluation of disease severity [by means of the apnea/hypopnea-index (AHI)] can be required. A subset of patients that prefer a CPAP alternative is still using CPAP until the reevaluation polysomnography (PSG), and a so-called washout effect is not ruled out. The purpose of this study is to evaluate the evidence on the existence and duration of this washout effect and its clinical relevance for current practice. Methods To identify papers for this review, an extensive literature search was run electronically through MEDLINE and EMBASE databases. Results An overview of currently available literature on this washout effect and the findings of 13 studies on this topic are discussed. Conclusion There is some evidence that CPAP washout exists in patients with a stable BMI throughout the follow-up period. However, the intensity and duration of this effect remains unclear. Within the limitations of the present study, it seems reasonable to maintain a washout period of 1 week, in case alternative treatments options are considered and especially when a baseline PSG (and subsequent repeat PSG after treatment) is needed in case of clinical trials.

Study Objectives: To study the possible predictive value of drug-induced sleep endoscopy (DISE) in assessing therapeutic response to implanted upper airway stimulation (UAS) for obstructive sleep apnea (OSA). Methods: During DISE, artificial sleep is induced by midazolam and/or propofol, and the pharyngeal collapse patterns are visualized using a flexible fiberoptic nasopharyngoscope. The level (palate, oropharynx, tongue base, hypopharynx/epiglottis), the direction (anteroposterior, concentric, lateral), and the degree of collapse (none, partial, or complete) were scored in a standard fashion. Results: We report on the correlation between DISE results and therapy response in 21 OSA patients (apnea-hypopnea index [AHI] 38.5 +/- 11.8/h; body mass index [BMI] 28 +/- 2 kg/m(2), age 55 +/- 11 y, 20 male/1 female) who underwent DISE before implantation of a UAS system. Statistical analysis revealed a significantly better outcome with UAS in patients (n = 16) without palatal complete concentric collapse (CCC), reducing AHI from 37.6 +/- 11.4/h at baseline to 11.1 +/- 12.0/h with UAS (p < 0.001). No statistical difference was noted in AHI or BMI at baseline between the patients with and without palatal CCC. In addition, no predictive value was found for the other DISE collapse patterns documented. Conclusions: The absence of palatal CCC during DISE may predict therapeutic success with implanted UAS therapy. DISE can be recommended as a patient selection tool for implanted UAS to treat OSA.

Mandibular repositioning appliances (MRA) are currently the most widespread and evaluated type of oral appliance used to treat obstructive sleep apnea (OSA). Although oral appliance therapy usually reduces snoring, it is not always as effective in treating OSA. The methods that have been described to predict treatment outcome with oral appliance therapy mostly have relied on retrospective analysis and there is a significant lack of uniformity concerning the predictive models. Therefore, the ability to predict treatment outcome of oral appliance therapy prospectively in the individual patient and, thereby, preselecting suitable OSA patients for oral appliance therapy, is still limited in clinical practice. The site of upper airway obstruction can be assessed by sleep nasendoscopy or drug-induced sleep endoscopy (DISE). Generally, a decision is made after performing the so-called chin-lift maneuver, whereby the mandible is brought forward maximally. Although allowing for a visual inspection of the effect of mandibular protrusion, the position itself is not reproducible and it remains to be determined to what extent it is physiologically tenable by the patient. Furthermore, the chin-lift maneuver requires a further opening of the mouth simply for allowing the dental sleep professional the possibility to grasp and protrude the mandible. At our multidisciplinary dental sleep clinic at the Antwerp University Hospital, we started using a bite simulation approach to investigate the patients protrusive characteristics prior to the modified multipart DISE procedure. This specific technique using a simulation bite, custom-made for each individual patient, during DISE is described in detail in this article.

Purpose The objective of this randomized controlled trial was to assess the additional effect of a chest-worn sleep position trainer (SPT) in patients with residual supine-dependent obstructive sleep apnea (sdOSA) under mandibular advancement device (MAD) therapy. Methods Baseline and follow-up polysomnography with MAD were performed. Twenty patients with sdOSA under MAD therapy underwent two consecutive randomized polysomnographies: one with SPT and one with combination of SPT + MAD. Data are presented as median (quartile 1, quartile 3). Results The SPT reduced the time spent in supine sleeping position compared to baseline and MAD therapy. Both MAD and SPT were individually effective in reducing the overall apnea/hypopnea index (AHI) significantly when compared to baseline from 20.8 (15.1; 33.6)/h at baseline to 11.0 (6.7; 13.8)/h and to 11.1 (3.5; 17.7)/h with MAD or SPT, respectively. The combination of SPT + MAD further reduced the overall AHI to 5.7 (3.6; 7.4), which was significantly lower than with MAD alone (p p Conclusions The results of this study indicate that combination of SPT + MAD leads to a higher therapeutic efficacy in patients with sdOSA under MAD therapy when compared to one of the treatment modalities alone.