Drug-induced sleep endoscopy in sleep-disordered breathing: report on 1,249 cases

Surgical failure guided by DISE in patients with obstructive sleep apnea: a systematic review and meta-analysis

OBJECTIVES

The failure rate and risk factors of upper airway surgery with drug induced sleep endoscopy (DISE) remain unknown in the treatment of obstructive sleep apnea (OSA). This review aims to analyze the failure rate of upper airway surgery with DISE and identify obstruction sites for surgical failure.

METHODS

A systematic review was conducted using PubMed, Embase, Web of Science, and Google Scholar until May 20th, 2023. We included studies that used DISE to assess obstructive sites before upper airway surgery and reported surgical failure rates and outcomes in patients with OSA.

RESULTS

25 studies with a total of 1522 patients were included in the systematic review and meta-analysis. Upper airway surgery guided by DISE had a relatively low failure rate of 37% (95% CI 0.31-0.44) in the random effects model (I2 = 85.97%, P < 0.001). According to the velum, oropharynx, tongue base, and epiglottis (VOTE) scoring system, major risk factors for surgical failure included circumferential collapse at the velum, lateral wall collapse and small tonsils at the oropharynx, anterior-posterior lingual collapse and complete collapse at the tongue base. High body mass index and large preoperative apnea hypopnea index were also risk factors for OSA surgical failure.

CONCLUSIONS

Upper airway surgery guided by DISE in patients with OSA had a low failure rate of 37%. DISE can identify obstruction sites associated with surgical failure and guide single-level and multi-level surgeries.

Polysomnographic airflow shapes and site of collapse during drug-induced sleep endoscopy

BACKGROUND

Differences in the pharyngeal site of collapse influence efficacy of non-continuous positive airway pressure therapies for obstructive sleep apnoea (OSA). Notably, complete concentric collapse at the level of the palate (CCCp) during drug-induced sleep endoscopy (DISE) is associated with reduced efficacy of hypoglossal nerve stimulation, but CCCp is currently not recognisable using polysomnography. Here we develop a means to estimate DISE-based site of collapse using overnight polysomnography.

METHODS

182 OSA patients provided DISE and polysomnography data. Six polysomnographic flow shape characteristics (mean during hypopnoeas) were identified as candidate predictors of CCCp (primary outcome variable, n=44/182), including inspiratory skewness and inspiratory scoopiness. Multivariable logistic regression combined the six characteristics to predict clear presence (n=22) versus absence (n=128) of CCCp (partial collapse and concurrent tongue base collapse excluded). Odds ratios for actual CCCp between predicted subgroups were quantified after cross-validation. Secondary analyses examined complete lateral wall, tongue base or epiglottis collapse. External validation was performed on a separate dataset (ntotal=466).

RESULTS

CCCp was characterised by greater scoopiness (β=1.5±0.6 per 2sd, multivariable estimate±se) and skewness (β=11.4±2.4) compared with non-CCCp. The odds ratio for CCCp in predicted positive versus negative subgroups was 5.0 (95% CI 1.9-13.1). The same characteristics provided significant cross-validated prediction of lateral wall (OR 6.3, 95% CI 2.4-16.5), tongue base (OR 3.2, 95% CI 1.4-7.3) and epiglottis (OR 4.4, 95% CI 1.5-12.4) collapse. CCCp and lateral wall collapse shared similar characteristics (skewed, scoopy), diametrically opposed to tongue base and epiglottis collapse characteristics. External validation confirmed model prediction.

CONCLUSIONS

The current study provides a means to recognise patients with likely CCCp or other DISE-based site of collapse categories using routine polysomnography. Since site of collapse influences therapeutic responses, polysomnographic airflow shape analysis could facilitate precision site-specific OSA interventions.

Eustachian Tube Function Symptoms in Palatal Surgeries for OSA: 3-Month Postoperative Analysis

OBJECTIVES

To assess the influence of different soft palate surgeries for obstructive sleep apnea (OSA) on eustachian tube function symptoms, considering various potential factors.

METHODS

A prospective, cohort study was conducted on patients who underwent isolated palatal surgeries for OSA at a single academic medical center between 2017 and 2022. Eustachian Tube Dysfunction Questionnaire (ETDQ-7) were assessed at baseline, 1-month, 2-month, and 3-month time points. Patients with retropalatal obstruction underwent tailored surgeries: anterior palatoplasty (AP), expansion sphincter palatoplasty (ESP), or barbed palatoplasty (BP). Baseline OSA severity between baseline and follow-up time points were also examined.

RESULTS

In this study, 96 patients with OSA were enrolled and allocated to three surgical groups: AP (n = 30), ESP (n = 32), and BP (n = 34). The mean age was 44.3 ± 10.2 years, with 86% male participants. No significant differences were found between the groups in terms of age, sex, and BMI. A two-way repeated measures ANOVA revealed a significant main effect of time on ETDQ-7 scores (p < 0.001), but no significant main effect of groups (p = 0.109) or interaction between time and groups (p = 0.082). Subgroup analysis showed a significant interaction for the 3-month change in ETDQ-7 scores by OSA severity (p = 0.046). In post hoc analysis, the BP group exhibited a higher mean ETDQ-7 score compared with the AP group at the 3-month follow-up.

CONCLUSION

This study highlights the importance of considering individual patient factors, such as OSA severity and eustachian tube function symptoms, when selecting the most appropriate surgical treatment to optimize outcomes.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:2471-2477, 2024.

Types of Epiglottic Collapse in Breathing Sleep Disorder and Their Impact in Clinical Practice

Introduction  Obstructive sleep apnea (OSA) is a severe form of sleep-disordered breathing (SDB) that is strongly correlated with comorbidities, in which epiglottic collapse (EC) and other contributing factors are involved. Objectives  To evaluate the occurrence of EC in OSA patients through drug-induced sleep endoscopy (DISE) and to determine the factors contributing to EC. Methods  A retrospective study of 37 adult patients using medical history. Patients were assessed for laryngopharyngeal reflux (LPR) and lingual tonsil hypertrophy (LTH) using reflux symptom index and reflux finding score (RFS); for OSA using polysomnography, and for airway collapse through DISE. An independent t -test was performed to evaluate risk factors, including the involvement of three other airway structures. Results  Most EC patients exhibited trap door epiglottic collapse (TDEC) (56.8%) or pushed epiglottic collapse (PEC) (29.7%). Lingual tonsil hypertrophy, RFS, and respiratory effort-related arousal (RERA) were associated with epiglottic subtypes. Laryngopharyngeal reflux patients confirmed by RFS (t(25) = -1.32, p  = 0.197) tended to suffer PEC; LTH was significantly associated (X2(1) = 2.5, p  = 0.012) with PEC (odds ratio [OR] value = 44) in grades II and III LTH patients; 11 of 16 TDEC patients had grade I LTH. Pushed epiglottic collapse was more prevalent among multilevel airway obstruction patients. A single additional collapse site was found only in TDEC patients. Conclusion  Laryngopharyngeal reflux causes repetitive acid stress toward lingual tonsils causing LTH, resulting in PEC with grade II or III LTH. Trap door epiglottic collapse requires one additional structural collapse, while at least two additional collapse sites were necessary to develop PEC. Respiratory effort-related arousal values may indicate EC.

Indications for Dental Specialists for Treating Obstructive Sleep Apnea with Mandibular Advancement Devices: A Narrative Review

Obstructive sleep apnea (OSA) syndrome is characterized by repeated airway collapse during sleep. It determines cardiovascular, pulmonary, and neurocognitive consequences and is associated with several daytime and nighttime symptoms that influence the patient's quality of life. The contribution of the dental specialist in the clinical management of OSA patients entails participating in the screening process as diagnostic sentinels and providing adequate treatment using mandibular advancement devices (MADs). Since the treatment of OSA requires a multidisciplinary approach, including different medical specialists, dentists should have a comprehensive understanding of medical and dental factors that influence the strategy and effectiveness of OSA treatment with MAD. Such expertise is crucial in determining the appropriate treatment indications and helps clinicians establish a consolidated position within the multidisciplinary OSA team. In this regard, this review summarizes the evidence of the clinical indications for MAD treatment and provides the dental specialist with helpful information about medical, functional, and other relevant factors that should be considered during diagnosis, treatment plan, and follow-up stages. Information retrieved was organized and discussed, generating specific domains/queries oriented to the clinical management of OSA patients from the clinical perspective of dental specialists.

Severity of tongue base collapse in various body positions in patients with obstructive sleep apnea: A trajectory analysis

BACKGROUND

Drug-induced sleep endoscopy (DISE) is used for evaluating upper airway anatomy and determining airway obstruction patterns. It is typically performed with the patient in the supine position. Airway collapse severity is influenced by body position and level of consciousness; the resultant dynamic changes may vary across patients. In this study, we evaluated the severity of upper airway collapse through awake endoscopy and DISE and identified factors affecting the pattern of airway collapse severity.

METHODS

This study included 66 patients with obstructive sleep apnea. The patients underwent type 1 polysomnography, tongue strength assessment, awake endoscopy in the sitting and supine positions, and DISE. Group-based trajectory modeling was performed to identify patients with different collapse severity patterns in different body positions and at different levels of consciousness.

RESULTS

Patient with similar severity trajectory were assigned to the same group. Two different severity trajectories (group 1 and group 2) were identified at the tongue base level. Tongue depression strength varied significantly between groups 1 and 2 (47.00 vs. 35.00 kPa; P = .047). During awake endoscopy, collapse severity was significantly higher in group 2 than in group 1. Group 1 had lower rapid eye movement/nonrapid eye movement apnea-hypopnea index ratios and higher tongue depression strength than did group 2.

CONCLUSION

In patients with obstructive sleep apnea, tongue strength may vary depending on body position. Our results should be interpreted with caution because of the limited sample size. Future studies should investigate the effect of oropharyngeal rehabilitation on tongue strength and collapse severity.

Quantitative Measurement of Pharyngeal Dimensions During Drug-induced Sleep Endoscopy for Oral Appliance Outcome

OBJECTIVE

To quantitatively investigate the effect of mandibular advancement devices (MADs) on pharyngeal airway dimensions in a transverse plane as measured during drug-induced sleep endoscopy (DISE).

METHODS

Data from 56 patients, treated with MAD at 75% maximal protrusion and with baseline Apnea-Hypopnea Index ≥10 events/h, were analyzed. For each patient, three snapshots were selected from DISE video footage at baseline, with MAD presence, and during chin lift, resulting in 498 images (168/168/162, baseline/MAD/chin lift). Cross-sectional areas, anteroposterior (AP) and laterolateral (LL) dimensions on both retroglossal and retro-epiglottic levels were measured. To define the effect of MAD and chin lift on pharyngeal dimensions, linear mixed-effect models were built. Associations between MAD treatment response and pharyngeal expansion (MAD/chin lift) were determined.

RESULTS

Significant differences were found between retroglossal cross-sectional areas, AP, and LL dimensions at baseline and with MAD presence. At a retro-epiglottic level, only LL dimensions differed significantly with MAD presence compared to baseline, with significant relation of LL expansion ratio to treatment response (p = 0.0176). After adjusting the response definition for the sleeping position, greater retroglossal expansion ratios were seen in responders (1.32 ± 0.48) compared to non-responders (1.11 ± 0.32) (p = 0.0441). No significant association was found between response and pharyngeal expansion by chin lift.

CONCLUSION

Our observations highlight the additional value of quantitative pharyngeal airway measurements during DISE with MAD presence in evaluating MAD treatment outcome. These findings demonstrate an increase in retroglossal airway dimensions during DISE, with MAD presence, and more pronounced increase in retroglossal expansion ratios in MAD treatment responders compared to non-responders after sleeping position correction.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:3619-3627, 2023.

Drug-induced sleep endoscopy-continuous positive airway pressure (DISE-CPAP), a newer modality to choose the right candidates for CPAP

BACKGROUND

Continuous positive airway pressure (CPAP) therapy is recommended for moderate-to-severe obstructive sleep apnea (OSA). We aimed to investigate whether or not combining drug-induced sleep endoscopy (DISE) with CPAP titration may inform more appropriate pressure settings.

MATERIALS AND METHODS

A sleep CPAP titration study and DISE-CPAP treatment were performed on consecutive subjects with moderate-to-severe OSA under controlled sedation using bispectral monitoring. Video recordings of dynamic changes in UA with CPAP pressure ranges of 5 to 25 cm were assessed in accordance with the VOTE classification. The 95th percentile (95th PC) pressure of the CPAP titration trial was compared to optimal pressure for alleviating UA blockage.

RESULTS

We included 30 subjects (mean age 37.5, 17% women). All showed UA collapse at more than one level, with more than 80% of them collapsing completely at the levels of the velum and oropharynx. At the velum, 90% of subjects experienced improvement with CPAP. At the oropharynx, 75% of subjects experienced improvement with CPAP. The mean pressure and standard deviation (SD) of the 95th PC of the CPAP titration was 14.3 (3.5) cmH2O, while the pressure required to partially or fully open the airway (best possible pressure) was 16.1 (3.9) cmH2O; mean (SD) difference, 1.9 (2.2); P ≤ 0.001. The limits of agreement between the CPAP 95th pressure and the ideal pressure were - 6.32 to + 2.52.

CONCLUSIONS

The palate and lateral pharynx were more affected by CPAP than the hypopharynx. Most of the time, the mean 95th PC CPAP titration pressure was lower than the mean optimal pressure needed to alleviate the collapse.

Patterns of Pharyngeal Obstruction and Collapse in Obese and Nonobese Children on Drug-Induced Sleep Endoscopy

OBJECTIVE

(1) Compare proportions of collapse, obstruction, or mixed instances on drug-induced sleep endoscopy findings of obese and nonobese children with obstructive sleep disordered breathing. (2) Determine the frequency of collapse in general between both groups.

STUDY DESIGN

Retrospective case-control study.

SETTING

Tertiary pediatric center.

METHODS

Obese (body mass index >95 percentile) children presenting with obstructive sleep disordered breathing (>33 on the pediatric sleep questionnaire) were identified from a prospectively kept surgical database. Only those who had undergone drug-induced sleep endoscopy were eligible. Age and sex pair-matched nonobese children were identified. Only nonsyndromic, neurologically normal, surgically naïve patients were included. The frequency of obstructive, collapse, and mixed pharyngeal patterns was documented in both groups. A comparison of proportions was then undertaken (χ2 test).

RESULTS

Over a 5-year period, 73 consecutive children with obesity were identified (40 males; mean of 8.5 ± 3.0 years, 2.8-13.1). They were matched with 73 nonobese children (8.4 ± 3.0 years, 2.6-14.1). The obese group exhibited significantly more pharyngeal collapses (62:47) (p = .0021 odds ratio [OR] 3.358, 95% confidence interval [CI] 1.52-7.42). The proportion of pharyngeal findings on drug-induced sleep endoscopy was significantly different (p = .000129) between the 2 groups; obese (61 mixed: 3 obstruction: 9 collapse) and nonobese (48 mixed: 22 obstruction: 4 collapse).

CONCLUSION

The predominance of hypopharyngeal collapse in children with obesity may explain the likelihood of failure of surgery directed at obstructive findings. This may also strengthen the case for drug-induced sleep endoscopy in this group at the initial surgery to guide it rather than after the failure of adenotonsillectomy.

The relationship between bi-spectral index and VOTE score in evaluation of drug-induced sleep endoscopy: A systematic meta-analysis

OBJECTIVE

The aim of this study was to investigate both the presence and severity of collapse in anatomical regions defined by the VOTE score (velum, orofarinx, tongue, and epiglottis), during drug induced sleep endoscopy (DISE) in patients diagnosed with obstructive sleep apnea, based on the bi-spectral index (BIS) sedation level.

METHODS

In order to conduct a meta-analysis of articles examining the relationship between the VOTE score and BIS sedation level in determining the presence and severity of upper airway collapse during DISE, a literature review was performed.

RESULTS

As a result of the search made in the specified databases, a total of 1864 articles were reached. Five articles included in this review that had sufficient statistical data to be included in the meta-analysis were found. A statistically significant correlation was found between the BIS sedation level and the areas of obstruction in the VOTE score. The strongest association is at the epiglottis level, followed by the velum, oropharynx, and tongue, respectively (CC: 0.639, CC: 0.53, CC: 0.49, and CC: 0.346, P < .001). In the subgroup analysis of publications with BIS sedation levels in the range of 60 to 65, the distribution in the epiglottis region was heterogeneous, and it was found to be statistically significant according to the random effect model (P < .001). The distribution in the tongue was homogeneous, and it was found to be statistically significant according to the fixed effect model (P < .001). When the publications in which the BIS sedation level is in the range of 65 to 75 are examined according to the areas of obstruction; the distribution in 4 anatomical regions was homogeneous and statistically significant according to the fixed effect model (P < .001).

CONCLUSION

It was found that BIS sedation levels during DISE application in obstructive sleep apnea patients were associated with obstruction of the anatomical regions of the upper airway. The strongest association was found at the epiglottis level, followed by the velum, oropharynx, and tongue, respectively. It is helpful to monitor the sedation level with BIS in order to better define the collapsed areas during DISE application. However, more studies are needed to better understand the relationship between BIS sedation values and sleep stages.

Barbed palatal surgery: single stage or multilevel setting-a systematic review by the Young Otolaryngologists of the Italian Society of Otolaryngology

PURPOSE

This systematic review aims to compare the efficacy and safety of multilevel and single level surgery, including barbed pharyngoplasties, in the treatment of obstructive sleep apnea (OSA).

METHODS

The study followed PRISMA guidelines and searched PubMed/MEDLINE, Google Scholar, and Ovid databases for studies evaluating the effect of barbed pharyngoplasties on adults with OSA. Prospective and retrospective cohort studies were included with pre- and post-treatment comparisons of sleep tests and self-reported clinical outcomes. Exclusion criteria were non-English studies, case reports, reviews, conference abstracts, letters, and pediatric studies. Successful surgery was classified using Sher's criteria.

RESULTS

The study selected a total of 1014 patients from 26 studies, 24 of which were longitudinal studies with 10 retrospective trials and 14 prospective studies. The average age of the patients was 46.9 years, with an average Body Mass Index (BMI) of 25.6 kg/m2. Most of the patients were male (84.6%). The study included only palatal surgical techniques with barbed sutures, and patients who underwent cardio-respiratory monitoring and Drug Induced Sleep Endoscopy (DISE) before surgery. Mean Apnea Hypopnea Index (AHI) preoperative was 32.9/h, AHI postoperative was 11.9/h, and mean reduction of AHI was 62.3%. The most commonly adopted palatoplasty was Barbed Repositioning Pharyngoplasty (BRP) in 16 out of 26 studies, followed by its subsequent modifications in 3 studies.

CONCLUSIONS

Barbed pharyngoplasties appear to be effective both on objective measurement and subjective scores. DISE represents a fundamental tool to assess uni-level or multilevel obstruction. When retro-palatal collapse is present, barbed pharyngoplasty appears to be effective. Barbed pharyngoplasties maintain their good results both in single level or multilevel surgery. Randomized clinical controlled trials with multi-center cooperation and long-term study are necessary.

International Consensus Statement on Obstructive Sleep Apnea

BACKGROUND

Evaluation and interpretation of the literature on obstructive sleep apnea (OSA) allows for consolidation and determination of the key factors important for clinical management of the adult OSA patient. Toward this goal, an international collaborative of multidisciplinary experts in sleep apnea evaluation and treatment have produced the International Consensus statement on Obstructive Sleep Apnea (ICS:OSA).

METHODS

Using previously defined methodology, focal topics in OSA were assigned as literature review (LR), evidence-based review (EBR), or evidence-based review with recommendations (EBR-R) formats. Each topic incorporated the available and relevant evidence which was summarized and graded on study quality. Each topic and section underwent iterative review and the ICS:OSA was created and reviewed by all authors for consensus.

RESULTS

The ICS:OSA addresses OSA syndrome definitions, pathophysiology, epidemiology, risk factors for disease, screening methods, diagnostic testing types, multiple treatment modalities, and effects of OSA treatment on multiple OSA-associated comorbidities. Specific focus on outcomes with positive airway pressure (PAP) and surgical treatments were evaluated.

CONCLUSION

This review of the literature consolidates the available knowledge and identifies the limitations of the current evidence on OSA. This effort aims to create a resource for OSA evidence-based practice and identify future research needs. Knowledge gaps and research opportunities include improving the metrics of OSA disease, determining the optimal OSA screening paradigms, developing strategies for PAP adherence and longitudinal care, enhancing selection of PAP alternatives and surgery, understanding health risk outcomes, and translating evidence into individualized approaches to therapy.

Comparative Efficacy of Velopharyngeal Surgery Techniques for Obstructive Sleep Apnea: A Systematic Review

Background: In recent years, surgical interventions for obstructive sleep apnea (OSA) have evolved rapidly, with numerous techniques described in the literature. The approach to velopharyngeal surgery for obstructive sleep apnea has transformed over time, shifting from an aggressive removal of redundant excess soft tissue to less invasive reconstruction techniques that aim to preserve pharyngeal function while effectively managing sleep apnea. This review aims to evaluate and compare the efficacy of the surgical techniques utilized for OSA at the level of the palate and pharynx. It will cover both traditional and novel procedures. Methods: A comprehensive search of the major databases, such as PubMed/MEDLINE, Web of Science, and Scopus, was conducted to identify the relevant literature. We included articles written in English that analyzed the outcomes of adult patients who received velopharyngeal surgery for sleep apnea. Only comparative studies that examined at least two techniques were considered. Results: In all of the studies combined, the total number of patients who underwent velopharyngeal surgery was 614 in eight studies. All surgical procedures resulted in improvements in the apnea-hypopnea index (AHI). The highest success rates and best outcomes were achieved by barbed reposition pharyngoplasty (BRP) in most studies, ranging from 64.29% to 86.6%. BRP also demonstrated the most significant improvements in both objective and subjective parameters closely followed by ESP that obtained similar efficiency in some studies, especially when combined with anterior palatoplasty (AP), but with a higher incidence of complications. While LP showed moderate efficiency compared with BRP or ESP, the UPPP techniques exhibited greater outcome variability among studies, with a success rate ranging from 38.71% to 59.26%, and the best results observed in a multilevel context. Conclusions: In our review, BRP was the most preferred, effective, and safe among all velopharyngeal techniques, closely followed by ESP. However, older described techniques also showed good results in well-selected patients. Larger-scale studies, preferably prospective, that rigorously incorporate DISE-based strict inclusion criteria might be needed to assess the efficacy of different techniques and generalize the findings.

Multilevel Airway Obstruction Phenotypes in Adult OSA

Objective

To describe multilevel phenotypes of airway obstruction identified on drug-induced sleep endoscopy (DISE) in adults.

Study Design

Retrospective chart review.

Setting

Tertiary care center.

Methods

Video recordings of DISE on adult patients were retrospectively scored. A cross-correlation matrix was created to detect significant correlations between DISE findings at anatomical subsites. Three multilevel phenotypes resulted from the matrix: complete collapse at the tongue base with complete collapse at the epiglottis (T2-E2), complete circumferential obstruction at the velum with complete lateral pharyngeal wall collapse at the oropharynx (V2C-O2LPW), and incomplete collapse at the velum with complete collapse due to tonsillar hypertrophy (V0/1-O2T). The mean difference (MD) and 95% confidence interval (CI) were calculated for demographic and polysomnogram metrics of each phenotype compared to all other subjects.

Results

Phenotype 1 (T2-E2) (n = 88) had older ages (MD 5.784 years, CI [1.992, 9.576]), lower body mass index (BMI) (MD -1.666 kg/m², CI [02.570, -0.762]), and smaller neck circumferences (MD -0.448 in., CI [-9.14, -0.009]) than the other phenotypes. Phenotype 2 (V2C-O2LPW) (n = 25) had higher BMIs (MD 2.813 kg/m², CI [1.362, 4.263]), higher neck circumference (MD 0.714 in., CI [0.004, 1.424]), and higher apnea-hypopnea index (MD 8.252, CI [0.463, 16.041]). Phenotype 3 (V0/1-O2T) (n = 20) had younger ages (MD -17.697, CI [-25.215, -11.179]).

Conclusion

Three distinct multilevel phenotypes of obstruction were identified on DISE, suggesting different anatomic subsites collapse in a nonrandom pattern. The phenotypes appear to represent distinct patient groups and their identification may have implications in terms of pathophysiology and treatment modalities.

Automatic scoring of drug-induced sleep endoscopy for obstructive sleep apnea using deep learning

BACKGROUND

Treatment of obstructive sleep apnea is crucial for long term health and reduced economic burden. For those considered for surgery, drug-induced sleep endoscopy (DISE) is a method to characterize location and pattern of sleep-related upper airway collapse. According to the VOTE classification system, four upper airway sites of collapse are characterized: velum (V), oropharynx (O), tongue (T), and epiglottis (E). The degree of obstruction per site is classified as 0 (no obstruction), 1 (partial obstruction), or 2 (complete obstruction). Here we propose a deep learning approach for automatic scoring of VOTE obstruction degrees from DISE videos.

METHODS

We included 281 DISE videos with varying durations (6 s-16 min) from two sleep clinics: Copenhagen University Hospital and Stanford University Hospital. Examinations were split into 5-s clips, each receiving annotations of 0, 1, 2, or X (site not visible) for each site (V, O, T, and E), which was used to train a deep learning model. Predicted VOTE obstruction degrees per examination was obtained by taking the highest predicted degree per site across 5-s clips, which was evaluated against VOTE degrees annotated by surgeons.

RESULTS

Mean F1 score of 70% was obtained across all DISE examinations (V: 85%, O: 72%, T: 57%, E: 65%). For each site, sensitivity was highest for degree 2 and lowest for degree 0. No bias in performance was observed between videos from different clinicians/hospitals.

CONCLUSIONS

This study demonstrates that automating scoring of DISE examinations show high validity and feasibility in degree of upper airway collapse.

Objective Pharyngeal Phenotyping in Obstructive Sleep Apnea With High-Resolution Manometry

OBJECTIVE

Drug-induced sleep endoscopy (DISE) is a commonly used diagnostic tool for surgical procedural selection in obstructive sleep apnea (OSA), but it is expensive, subjective, and requires sedation. Here we present an initial investigation of high-resolution pharyngeal manometry (HRM) for upper airway phenotyping in OSA, developing a software system that reliably predicts pharyngeal sites of collapse based solely on manometric recordings.

STUDY DESIGN

Prospective cross-sectional study.

SETTING

An academic sleep medicine and surgery practice.

METHODS

Forty participants underwent simultaneous HRM and DISE. A machine learning algorithm was constructed to estimate pharyngeal level-specific severity of collapse, as determined by an expert DISE reviewer. The primary outcome metrics for each level were model accuracy and F1-score, which balances model precision against recall.

RESULTS

During model training, the average F1-score across all categories was 0.86, with an average weighted accuracy of 0.91. Using a holdout test set of 9 participants, a K-nearest neighbor model trained on 31 participants attained an average F1-score of 0.96 and an average accuracy of 0.97. The F1-score for prediction of complete concentric palatal collapse was 0.86.

CONCLUSION

Our findings suggest that HRM may enable objective and dynamic mapping of the pharynx, opening new pathways toward reliable and reproducible assessment of this complex anatomy in sleep.

The clinical application progress and potential of drug-induced sleep endoscopy in obstructive sleep apnea

Background and Objective: Obstructive sleep apnoea (OSA) is characterized by nocturnal repetitive upper airway (UA) collapse. For sleep physicians, the recognition of UA collapse characteristics is critical for understanding OSA mechanisms and developing individualized treatment plans. Drug-induced sleep endoscopy (DISE) is an exam during simulated sleep that allows the dynamic assessment of the UA of individuals with OSA. The initial recognition of DISE was to locate the sites of UA obstruction and direct the surgical selection of OSA since it was introduced in the 1990s. After approximately 30 years of studies, based on advances in endoscopic operative techniques and innovative treatments of OSA, DISE had been performed to explore mechanisms and comprehensive treatments related to UA collapse. Methods: This article reviewed contemporary DISE advances, including indications and contraindications, technique of induced sleep, endoscopic operation, UA characteristics classification.Results and Conclusions: Precise selection based on the association between collapse patterns and treatment modalities, such as continuous positive airway pressure, oral appliance, positional therapy, robotic surgery and neurostimulator implanting, is the future research prospect based on DISE.Key messagesDISE provides sleep physicians with valuable information about the upper airway collapse characteristics and dynamic changes during sleep.The studies based on DISE findings improve the selectivity and efficiency of treatment modalities, including classical therapies such as continuous positive airway pressure, oral appliance, positional therapy, and innovative therapies such as neurostimulator implanting and robotic surgery, promote the advancement of OSA precision medicine.

Volume of parapharyngeal fat pad in obstructive sleep apnea syndrome: prognostic role for multilevel sleep surgery

STUDY OBJECTIVES

To evaluate the prognostic role of volume of parapharyngeal fat pad (VPPFP) after multilevel sleep surgery in patients with obstructive sleep apnea syndrome.

METHODS

This retrospective cohort study was conducted in 50 patients with moderate to severe obstructive sleep apnea syndrome who underwent polysomnography (preoperative and postoperative 6 months) and preoperative facial computed tomography with multilevel sleep surgery between May 2010 and February 2019. All patients had failed or refused positive airway pressure treatment.

RESULTS

Of the 50 patients with moderate to severe obstructive sleep apnea syndrome who underwent multilevel sleep surgery, 46 were male (92.0%) with mean ± standard deviation age of 41.2 ± 12.5 years. On the preoperative polysomnography, mean ± standard deviation of apnea-hypopnea index and CT90 (cumulative percentage of time spent at oxygen saturation less than 90%) were 43.4 ± 19.3 events/h and 5.6 ± 9.6%, respectively. The average VPPFP measured by facial computed tomography scan was 4.9 ± 1.9 cm3. Multiple linear regression analysis showed that VPPFP was significantly correlated (R2 = 0.38) with age (β = 0.05; 95% confidence interval [CI], 0.01-0.09) and body mass index (β = 0.31; 95% CI, 0.16-0.45). Surgical success rate was 38%, and VPPFP higher than 5.1 cm3 was significantly associated with surgical failure after covariate adjustment (P = .01; odds ratio = 0.09; 95% CI, 0.02-0.48). Postoperative apnea-hypopnea index was positively correlated (R2 = 0.40) with CT90 (β = 1.33; 95% CI, 0.74-1.92) and VPPFP (β = 3.52; 95% CI, 0.30-6.74).

CONCLUSIONS

VPPFP correlated with age and body mass index, and high VPPFP and CT90 were associated with high postoperative apnea-hypopnea index. VPPFP larger than 5.1 cm3 was a possible risk factor for surgical failure, which may inform a decision on multilevel sleep surgery as salvage therapy for positive airway pressure treatment.

CITATION

Kim BK, Park SI, Hong SD, Jung YG, Kim HY. Volume of parapharyngeal fat pad in obstructive sleep apnea syndrome: prognostic role for multilevel sleep surgery. J Clin Sleep Med. 2022;18(12):2819-2828.

Comparison of readmission and complication rates between traditional sleep surgery and hypoglossal nerve stimulation

Objective

This study aims to compare readmission and complication rates between hypoglossal nerve stimulation (HNS) and traditional sleep surgery (TSS) in the 90‐day postoperative period using a federated electronic health record (EHR) database.

Methods

We queried TriNetX, a global federated health research network providing access to EHR data from approximately 70 million patients in 49 large health care organizations to identify individuals who underwent either HNS or TSS for obstructive sleep apnea (OSA) from April 2014 to March 2021. Propensity scores based on demographics and obesity were used to balance groups. We compared the frequency of readmission/representation and surgical‐related complication rates between cohorts.

Results

After propensity score matching of HNS versus palatal surgery (n = 1014 in each cohort) and HNS versus multilevel surgery (n = 374 in each cohort), we found palatal and multilevel surgery had a significantly higher risk of readmission versus HNS. (12% vs. 4%, p < .0001). Palatal surgery complication rate was also higher than HNS (21% vs. 2%, p < .0001). Multi‐level surgery results were similarly higher (22% vs. 3%, p < .001). The most common diagnoses at ER readmission for TSS were procedural complications and pain, while common diagnoses for HNS readmission were general complaints such as malaise and headache.

Conclusions

Hypoglossal nerve stimulation has lower risk of readmission and postoperative complications than traditional sleep surgery as demonstrated in a large research network database analysis.

Level of Evidence: 3.

This study aims to compare readmission and complication rates between hypoglossal nerve stimulation, a novel implantable neurostimulation system to treat selected CPAP‐intolerant obstructive sleep apnea by stimulating the distal branches of the hypoglossal nerve, against traditional sleep surgery methods in the 90‐day postoperative period using a federated electronic health record database. We found that hypoglossal nerve stimulation has a significantly lower risk of readmission and postoperative complications than traditional sleep surgery.

Predicting upper airway collapse sites found in drug-induced sleep endoscopy from clinical data and snoring sounds in patients with obstructive sleep apnea: a prospective clinical study

STUDY OBJECTIVES

The primary aim was to predict upper airway collapse sites found in drug-induced sleep endoscopy (DISE) from demographic, anthropometric, clinical examination, sleep study, and snoring sound parameters in patients with obstructive sleep apnea (OSA). The secondary aim was to identify the above-mentioned parameters that are associated with complete concentric collapse of the soft palate.

METHODS

All patients with OSA who underwent DISE and simultaneous snoring sound recording were enrolled in this study. Demographic, anthropometric, clinical examination (viz., modified Mallampati classification and Friedman tonsil classification), and sleep study parameters were extracted from the polysomnography and DISE reports. Snoring sound parameters during DISE were calculated.

RESULTS

One hundred and nineteen patients with OSA (79.8% men; age = 48.1 ± 12.4 years) were included. Increased body mass index was found to be associated with higher probability of oropharyngeal collapse (P < .01; odds ratio = 1.29). Patients with a high Friedman tonsil score were less likely to have tongue base collapse (P < .01; odd ratio = 0.12) and epiglottic collapse (P = .01; odds ratio = 0.20) than those with a low score. A longer duration of snoring events (P = .05; odds ratio = 2.99) was associated with a higher probability of complete concentric collapse of the soft palate.

CONCLUSIONS

Within the current patient profile and approach, given that only a limited number of predictors were identified, it does not seem feasible to predict upper airway collapse sites found in DISE from demographic, anthropometric, clinical examination, sleep study, and snoring sound parameters in patients with OSA.

CITATION

Huang Z, Bosschieter PFN, Aarab G, et al. Predicting upper airway collapse sites found in drug-induced sleep endoscopy from clinical data and snoring sounds in obstructive sleep apnea patients: a prospective clinical study. J Clin Sleep Med. 2022;18(9):2119-2131.

Association between antidepressants, benzodiazepine and all-cause mortality in elderly hip fracture: A Korean nationwide cohort study

BACKGROUND

The purpose of this study was to analyze the association between the preoperative and postoperative use of antidepressant and benzodiazepine and all-cause mortality in elderly hip fracture patients.

METHODS

Patients who underwent surgical treatment for hip fracture over 65 years old were classified into Past-user, Current-user, and Non-users for each period according to use history for antidepressants or benzodiazepines. And, for the subgroup analysis, patients were classified by presence of past history for psychiatric medication. A multivariable-adjusted Cox proportional hazards model was used to investigate the effects of antidepressants and benzodiazepines on all-cause mortality.

RESULTS

A total of 15,576 patients were included in this study. Past users of antidepressants and benzodiazepines were 5699 (36.59%) patients and 11,319 (72.67%) patients, respectively. Current users of antidepressants and benzodiazepines were 2888 (18.54%) patients and 6287 (40.36%) patients, respectively. There were no statistically significant differences in the adjusted hazard for death compared to the non-users for both the past and the current users (p > 0.05). In the subgroup analysis, there were 12,502 once-users and 3074 never-users according to psychiatric medication. Current uses of antidepressants and benzodiazepine in the once-user did not increase adjusted hazard for death compared to the non-users (p>0.05). However, current uses of antidepressants by never-users increased the adjusted hazard for death compared to the non-user (adjusted hazard ratio, 1.31; 95% CI, 1.08-1.59; p = 0.007).

CONCLUSIONS

No association was observed between the uses of antidepressants and benzodiazepines after hip fracture and mortality risk in elderly patients who received psychiatric medication before hip fracture. However, the use of these medications was associated with increased all-cause mortality risk in patients who had no history of psychiatric medication before hip fracture.

LEVEL OF EVIDENCE

III, retrospective cohort study.

Guidelines of the French Society of ENT (SFORL): Drug-induced sleep endoscopy in adult obstructive sleep apnea syndrome

OBJECTIVES

To determine the indications, anesthesiological and surgical procedure and interest of drug-induced sleep endoscopy in the treatment of adult obstructive sleep apnea syndrome.

DESIGN

A redactional committee of 17 experts was set up. Conflicts of interest were disclosed and followed up throughout the process of drawing up the guidelines. The work received no funding from any firm dealing in health products (drugs or devices). The GRADE (Grading of Recommendations Assessment, Development and Evaluation) method was applied to assess the quality of the data on which the guidelines were founded. It was stressed that strong recommendations should not be made on the basis of poor-quality or insufficient data.

METHODS

The committee studied 29 questions on 5 topics: indications and contraindications, anesthetic technique, surgical technique, interpretation and reporting of results, and management guided by results.

RESULTS

Expert review and application of the GRADE method led to 30 guidelines: 10 with high level of evidence (Grade 1+ or 1-), 19 with low level (GRADE 2+ or 2-) and 1 expert opinion.

CONCLUSION

Experts fully agreed on the strong guidelines formalizing the indications and modalities of drug-induced sleep endoscopy for adult obstructive sleep apnea syndrome.

Anxiety, depression and sleepiness in OSA patients treated with barbed reposition pharyngoplasty: a prospective study

PURPOSE

To evaluate the efficacy of barbed reposition pharyngoplasty (BRP) on sleepiness, anxiety, and depression o adult patients with obstructive sleep apnea (OSA).

METHODS

We performed a prospective multicentric study to assess functional outcomes in 20 OSA patients treated with BRP and compare the results with an observational group of 20 subjects. All recruited subjects performed at baseline and 6-months postoperative follow-up Polysomnography (PSG), daytime sleepiness scoring using the Epworth Sleepiness Scale (ESS), and anxiety and depression evaluation via the Beck Anxiety Inventory (BAI) and the Beck Depression Inventory-II (BDI-II) questionnaires.

RESULTS

At follow-up the BRP demonstrated greater improvements in AHI (8.92 ± 2.29 vs. 30.66 ± 2.56; p < 0.001) and ODI (7.65 ± 2.39 vs. 24.55 ± 3.20; p < 0.001) than control at intergroup analysis. Surgical group reported significant data in daytime sleepiness (5.15 ± 1.19 vs. 13.15 ± 1.35; p < 0.001), anxiety (12.65 ± 3.11 vs. 24.2 ± 2.37; p < 0.001), and depression domains (5.85 ± 1.19 vs. 17.55 ± 3.24; p < 0.001). AHI, ODI, and advanced age have been shown to multiple regression as independent predictors of treatment response for mood domains (p < 0.001; p = 0.02; p = 0.041, respectively).

CONCLUSIONS

Patients with OSA may benefit from palate surgery, reducing not only the apnea and hypopnea index, daytime sleepiness but also associated mood comorbidities. However, further studies are needed to confirm our preliminary results to validate the evidence to date reported.

Critical to Know Pcrit: A Review on Pharyngeal Critical Closing Pressure in Obstructive Sleep Apnea

It is crucial to understand the underlying pathophysiology of obstructive sleep apnea (OSA). Upper airway collapsibility is an important pathophysiological factor that affects the upper airway in OSA. The aim of the current study was to review the existing body of knowledge on the pharyngeal collapsibility in OSA. After a thorough search through Medline, PubMed, Scopus, and Web of science, the relevant articles were found and used in this study. Critical closing pressure (Pcrit) is the gold standard measure for the degree of collapsibility of the pharyngeal airway. Various physiological factors and treatments affect upper airway collapsibility. Recently, it has been shown that the baseline value of Pcrit is helpful in the upfront selection of therapy options. The standard techniques to measure Pcrit are labor-intensive and time-consuming. Therefore, despite the importance of Pcrit, it is not routinely measured in clinical practice. New emerging surrogates, such as finite element (FE) modeling or the use of peak inspiratory flow measurements during a routine overnight polysomnography, may enable clinicians to have an estimate of the pharyngeal collapsibility. However, validation of these techniques is needed.

Evaluation and Management of Snoring

Snoring can be harmless (primary) or a symptom of sleep-disordered breathing (secondary) and should alert the physician to evaluate the patient for risks thereof. Phenotypes of snoring and sleep-disordered breathing (SDB) are anatomic and nonanatomic and identifying these phenotypes and their interrelationships are critical to effective therapy. Mouth breathing alerts the physician to nasal airway obstruction, signals orofacial growth changes in children, and heralds the progression of SDB. Systematic evaluation to establish phenotypes includes assessing sleep habits, comorbidities, upper airway examination, polysomnography, and drug-induced sleep endoscopy. Strategies for treatment should be personalized and precise to the phenotype(s) to achieve the most benefit.

Identifying Patient Characteristics That Predict Drug-Induced Sleep Endoscopy Anatomy

OBJECTIVE

To examine if age, sex, body mass index (BMI), neck circumference, or apnea-hypopnea index can predict whether a patient will demonstrate velopharyngeal complete circumferential (CC) collapse on drug-induced sleep endoscopy (DISE).

STUDY DESIGN

Single-center retrospective review at The Ohio State Wexner Medical Center of 289 patients between March 2014 and June 2020.

SETTING

Quaternary care hospital.

METHODS

Patient characteristic and DISE information was extracted from charts and summarized with mean and standard deviation for continuous variables and count and percentage for categorical. CC collapse and patient characteristic associations were explored: 2-sample t test for continuous and chi-square test for categorical. Classification and regression tree (CART) analysis with 3-fold cross-validation was employed to search for the best CC collapse predictors.

RESULTS

Male and female BMI and female neck circumference were correlated to velopharyngeal CC collapse, with BMI more strongly correlated. CART analysis for males showed that a BMI ≤34.8 kg/m² is associated with an 89.4% chance of not demonstrating velopharyngeal CC collapse vs 48% for BMI >34.8 (area under the curve [AUC] = 0.705; AUC >0.7 is acceptable). For females, the CART analysis showed that a BMI ≤36.4 is associated with a 98.4% of not demonstrating velopharyngeal CC collapse vs 30.8% for BMI >36.4 (AUC = 0.73). For females, a neck circumference ≤38.05 cm is associated with a 100% chance of not demonstrating velopharyngeal CC collapse vs 18.4% for >38.05 cm (AUC = 0.72).

CONCLUSION

The BMI values for males and females and the female neck circumference values established by the CART model may accurately predict DISE anatomy and possible candidacy for hypoglossal nerve stimulation.

Comparison of Drug-Induced Sleep Endoscopy and Natural Sleep Endoscopy in the Assessment of Upper Airway Pathophysiology During Sleep: Protocol and Study Design

Study Objectives: Obstructive sleep apnea (OSA) is increasingly recognized as a complex and heterogenous disorder. As a result, a "one-size-fits-all" management approach should be avoided. Therefore, evaluation of pathophysiological endotyping in OSA patients is emphasized, with upper airway collapse during sleep as one of the main features. To assess the site(s) and pattern(s) of upper airway collapse, natural sleep endoscopy (NSE) is defined as the gold standard. As NSE is labor-intensive and time-consuming, it is not feasible in routine practice. Instead, drug-induced sleep endoscopy (DISE) is the most frequently used technique and can be considered as the clinical standard. Flow shape and snoring analysis are non-invasive measurement techniques, yet are still evolving. Although DISE is used as the clinical alternative to assess upper airway collapse, associations between DISE and NSE observations, and associated flow and snoring signals, have not been quantified satisfactorily. In the current project we aim to compare upper airway collapse identified in patients with OSA using endoscopic techniques as well as flow shape analysis and analysis of tracheal snoring sounds between natural and drug-induced sleep. Methods: This study is a blinded prospective comparative multicenter cohort study. The study population will consist of adult patients with a recent diagnosis of OSA. Eligible patients will undergo a polysomnography (PSG) with NSE overnight and a DISE within 3 months. During DISE the upper airway is assessed under sedation by an experienced ear, nose, throat (ENT) surgeon using a flexible fiberoptic endoscope in the operating theater. In contrast to DISE, NSE is performed during natural sleep using a pediatric bronchoscope. During research DISE and NSE, the standard set-up is expanded with additional PSG measurements, including gold standard flow and analysis of tracheal snoring sounds. Conclusions: This project will be one of the first studies to formally compare collapse patterns during natural and drug-induced sleep. Moreover, this will be, to the authors' best knowledge, the first comparative research in airflow shape and tracheal snoring sounds analysis between DISE and NSE. These novel and non-invasive diagnostic methods studying upper airway mechanics during sleep will be simultaneously validated against DISE and NSE. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT04729478.

Evaluation of drug-induced sleep endoscopy as a tool for selecting patients with obstructive sleep apnea for maxillomandibular advancement

STUDY OBJECTIVES

(1) to investigate if DISE findings are predictive of surgical response for patients undergoing MMA for OSA; and (2) to investigate the predictive value of jaw thrust maneuver during DISE in terms of surgical response to MMA.

METHODS

A retrospective cohort study was conducted on patients with OSA who underwent a baseline polysomnography (PSG) and DISE followed by MMA and a 3-6-months follow-up PSG, between September 1, 2011 and September 30, 2020.

RESULTS

Sixty-four OSA patients (50 males [78.1%]; mean ± SD age = 51.7 ± 9.5 years; mean ± SD AHI = 49.0 ± 20.8 events/hour) were included. Thirty-nine patients were responders, and twenty-five were nonresponders. Adjusting for baseline characteristics and surgical characteristics (e.g., age, baseline AHI, degree of maxillary advancement), patients with complete anteroposterior epiglottic collapse had 0.239 times lower odds for response to MMA (95% confidence interval, 0.059-0.979; P = 0.047). No significant relationship was found between complete concentric velum collapse and MMA response. There was no statistically significant association between effect of jaw thrust maneuver during DISE on upper airway patency and treatment outcome of MMA.

CONCLUSIONS

This study indicates that DISE is a promising tool in order to identify patients who will or will not respond to MMA for treating OSA. Patients with complete anteroposterior epiglottic collapse may be less suitable candidates for MMA.

[The safety and short-term efficacy of modified lateral pharyngoplasty combined with multilevel surgery for OSA]

Objective:To explore the safety and short-term efficiency of modified lateral pharyngoplasty combined with surgeries in other sites including nose and tongue. Methods:Thirty-five patients with OSA confirmed with polysomnography received modified lateral pharyngoplasty under general anesthesia. Some of the patients may also receive glossopharyngeal or nasal surgeries according to their physical examination, Müller test with electronic nasolaryngology and polysmnography. The postoperativepain, capacities of swallowing and speaking, and related postoperative complications after surgeries were recorded. And the changes of epworth sleep scale （ESS） snoring sore, apnea and hypopnea index （AHI） and lowest oxygen saturation （LSaO2） were compared before and after surgeries. Results:Among the 35 patients, 1 patient experienced experienced dyspnea after extubation and 2 patients experienced postoperative bleeding. The mean VAS after 1, 4 and 7 days of the surgery were 5.41±2.42, 2.93±1.80, 2.91±1.26, respectively. The mean pain visual analogue scale（VAS） was 5.41±2.42, 2.93±1.80 and 2.91±1.26 on the 1st, 4th and 7th day after operation. The mean time of starting to eat liquid and semi-liquid were （3.23±2.11） dand （5.55±2.67） d after surgery, respectively. Twenty-eight patients underwent 3-6 months follow-up, there was no significant difference in body mass index （BMI） before and after surgery, while mean ESS and snore index were significantly improved, ESS decreased from 11.33±4.91 to 6.19±4.45, and snore index decreased from 6.93±2.23 to 1.25±1.96. Among them, 23 of patients those patients received polysomnography after surgeries, AHI, LSaO2 and time with oxygen saturation below 90% （CT90） were significantly improvement. The mean AHI decreased from 45.05±27.90/h to 18.61±20.85/h，and mean SaO2 increased from 71.17% to 80.87%. Conclusion:Modified lateral pharyngoplasty combined with selective nasal and lingual plane surgery in the treatment of OSA is safe and can significantly improve ESS, snoring, AHI， LSaO2and other indicators.Modified lateral pharyngoplasty selectively with surgeries of nose or tongue is a kind of safe and effective surgery to treat OSA that ESS, snoring, AHI and SaO2can have satisfactory improvement.

Quantification of the Impact of Intraoperative Ultrasound in Transoral Robotic Tongue Base Reduction

OBJECTIVES/HYPOTHESIS

Transoral robotic surgery (TORS) in the base of the tongue (BOT) reduction has been shown to decrease the apnea-hypopnea index (AHI) and improve daytime sleepiness in obstructive sleep apnea (OSA) patients. Intraoperative ultrasound (IOU) can be employed to guide the surgery and prevent massive bleeding.

STUDY DESIGN

Cohort study with historical control.

METHODS

A cohort study to compare the outcomes between OSA patients who received TORS with and without IOU assistance.

RESULTS

From 2016 to 2019, this study enrolled 80 OSA patients who underwent TORS in BOT: 57 in the IOU(+) and 23 in IOU(-) groups. The TORS with IOU presented with shorter operative time, less blood loss, and greater excised BOT volume. The IOU(+) group had greater improvement in the AHI and subjective questionnaire evaluation. The excised volume of BOT was significantly associated with the change in AHI.

CONCLUSION

The IOU could improve outcomes in BOT reduction surgery without raising the risk of surgical complications.

LEVEL OF EVIDENCE

4 Laryngoscope, 2021.

Assessment of Site, Degree and Pattern of Airway Obstruction in Patients with Moderate to Severe Obstructive Sleep Apnoea (OSA) Using Drug Induced Sleep Endoscopy (DISE)and Its Association with Awake Fibreoptic Evaluation and Polysomnography Parameters

Accurate assessment of site of obstruction in Obstructive Sleep Apnoea (OSA) is key to its effective management, especially the surgical intervention. Currently, Drug induced sleep endoscopy (DISE) is widely used to assess the obstruction during sleep as assessing during physiologic sleep is impractical and cumbersome. To assess the site, pattern and degree of airway obstruction in patients with moderate to severe obstructive sleep apnoea using DISE and to find a co-relation of DISE findings with awake fibreoptic assessment and severity of OSA. 41 adult patients (29 males, 12 females, mean AHI 40.58 ± 16.94, mean age 54 ± 9.15 years underwent awake fibreoptic nasal endoscopy in the outpatient department and propofol induced DISE in the main operation theatre. The site/s, degree and pattern of obstruction were recorded as per VOTE and Fujita classification. Velum was the commonest site of collapse followed by oropharynx, base of tongue and epiglottis. All had multilevel collapse with velum, oropharynx and base of tongue being the most common combination. At velum, base of tongue and epiglottis, antero-posterior pattern of collapse was commonest and at oropharynx lateral pattern of collapse was the commonest. We found no difference in the site, pattern or severity of collapse between the moderate and severe group though there was a tendency of epiglottis collapse being present more frequently in severe OSA. Awake fibreoptic endoscopic evaluation was able to assess the collapse at level of velum with higher sensitivity but with poor specificity. There was high chances of missing a hypopharyngeal collapse with fibreoptic endoscopic evaluation.

Natural sleep endoscopy in obstructive sleep apnea: A systematic review

This study's objective is to systematically review the literature on natural sleep endoscopy (NSE), including the set-up, different scoring systems, visualized collapse patterns during natural sleep, additional measurements, and comparison of upper airway collapse between NSE and drug-induced sleep endoscopy (DISE). A computerized search on Medline, Web of Science and the Cochrane library was conducted, obtaining 39 hits. Ten prospective studies were included in which NSE was performed in adults with obstructive sleep apnea (OSA). This study's findings suggest the soft palate to be the most frequent site of obstruction (58.8 %), followed by the tongue base (43.2 %), lateral walls (29.9 %), and epiglottis (22.4 %), which is in line with previous findings during DISE. Based on this literature review, the authors conclude that at this stage high quality, comparative research between DISE and NSE is missing. To adequately compare findings between OSA patients, endoscopic classification of upper airway collapse should be standardized. Non-invasive predictive tools to determine pharyngeal collapse are currently under investigation and may obviate the need for invasive endoscopy. This review highlights the contribution of NSE in validating such novel diagnostic methods and in studying upper airway mechanics in a research setting, yet larger and adequately powered studies are needed.

Improving outcomes of hypoglossal nerve stimulation therapy: current practice, future directions and research gaps. Proceedings of the 2019 International Sleep Surgery Society Research Forum

Hypoglossal nerve stimulation (HGNS) has evolved as a novel and effective therapy for patients with moderate-to-severe obstructive sleep apnea (OSA). Despite positive published outcomes of HGNS, there exist uncertainties regarding proper patient selection, surgical technique, and the reporting of outcomes and individual factors that impact therapy effectiveness. According to current guidelines, this therapy is indicated for select patients, and recommendations are based on the Stimulation Therapy for Apnea Reduction (STAR) trial. Ongoing research and physician experiences continuously improve methods to optimize the therapy. An understanding of the way in which airway anatomy, OSA phenotypes, individual health status, psychological conditions and comorbid sleep disorders influence the effectiveness of HGNS is essential to improve outcomes and expand therapy indications. This manuscript presents discussions on current evidence, future directions, and research gaps for HGNS therapy from the 10th International Surgical Sleep Society expert research panel.

Association of Snoring Characteristics with Predominant Site of Collapse of Upper Airway in Obstructive Sleep Apnoea Patients

STUDY OBJECTIVES

Acoustic analysis of isolated events and snoring by previous researchers suggests a correlation between individual acoustic features and individual site of collapse events. In this study, we hypothesised that multi-parameter evaluation of snore sounds during natural sleep would provide a robust prediction of the predominant site of airway collapse.

METHODS

The audio signals of 58 OSA patients were recorded simultaneously with full night polysomnography. The site of collapse was determined by manual analysis of the shape of the airflow signal during hypopnoea events and corresponding audio signal segments containing snore were manually extracted and processed. Machine learning algorithms were developed to automatically annotate the site of collapse of each hypopnoea event into three classes (lateral wall, palate and tongue-base). The predominant site of collapse for a sleep period was determined from the individual hypopnoea annotations and compared to the manually determined annotations. This was a retrospective study that used cross-validation to estimate performance.

RESULTS

Cluster analysis showed that the data fits well in two clusters with a mean silhouette coefficient of 0.79 and an accuracy of 68% for classifying tongue/non-tongue collapse. A classification model using linear discriminants achieved an overall accuracy of 81% for discriminating tongue/non-tongue predominant site of collapse and accuracy of 64% for all site of collapse classes.

CONCLUSIONS

Our results reveal that the snore signal during hypopnoea can provide information regarding the predominant site of collapse in the upper airway. Therefore, the audio signal recorded during sleep could potentially be used as a new tool in identifying the predominant site of collapse and consequently improving the treatment selection and outcome.

Concentric vs Anteroposterior-Laterolateral Collapse of the Soft Palate in Patients With Obstructive Sleep Apnea

The presence of complete concentric collapse of the soft palate (CCCp) during drug-induced sleep endoscopy (DISE) has important therapeutic consequences. However, CCCp may present in various, sometimes doubtful, ways due to the complex anatomy of the upper airway. Herein, we aimed to characterize these doubtful variants by reviewing the DISE recordings of patients with obstructive sleep apnea (n = 332). We observed in some individuals that the soft palate collapsed in an anteroposterior-laterolateral (AP-LL) way, producing a polygonal shape that was distinct from CCCp. Patients with this collapse pattern (n = 29) had a smaller neck circumference and less severe obstructive sleep apnea than patients with CCCp (n = 68). The majority of patients with AP-LL collapse (n = 19) were originally diagnosed with CCCp. Based on these findings, AP-LL collapse of the soft palate might represent a distinct DISE phenotype that is easily confounded with CCCp.

Ansa cervicalis stimulation increases pharyngeal patency in patients with obstructive sleep apnea

Hypoglossal nerve stimulation (HNS) is an alternative treatment option for obstructive sleep apnea (OSA) that reduces pharyngeal collapsibility, but HNS nonresponders often demonstrate continued retropalatal and lateral pharyngeal wall collapse. Recent evidence suggests that caudal pharyngeal traction with sternothyroid muscle contraction via ansa cervicalis stimulation (ACS) can also stabilize the pharynx, but the underlying mechanisms have not been elucidated. Our objective was to evaluate the effect of ACS on pharyngeal patency during expiration when the airway is most hypotonic. Eight participants with OSA underwent sustained ultrasound-guided fine-wire stimulation of the medial branch of the right hypoglossal nerve with and without transient stimulation of the branch of the ansa cervicalis nerve plexus innervating the right sternothyroid muscle during drug-induced sleep endoscopy. Airway cross-sectional area and expiratory airflow (V̇e) were measured from endoscopy video with ImageJ and pneumotachometry, respectively. ACS significantly increased retropalatal cross-sectional area (CSA_RP) to 211% [159-263] of unstimulated CSA_RP (P < 0.05). Adding ACS to HNS increased CSA_RP from baseline by 341% [244-439] (P < 0.05), a 180% [133-227] increase over isolated HNS (P < 0.05). ACS increased V̇e from baseline by 177% [138-217] P < 0.05). Adding ACS to HNS increased V̇e by 254% [207-301], reflecting decreases in pharyngeal collapsibility. Combining ACS with HNS increased retropalatal cross-sectional area and increased expiratory airflow, suggesting decreases in pharyngeal collapsibility. Our findings suggest that ACS exerts caudal traction on the upper airway through sternothyroid muscle contraction and that it may augment HNS efficacy in patients with OSA.NEW & NOTEWORTHY Ansa cervicalis stimulation (ACS) is a recently proposed neurostimulation mechanism for generating caudal pharyngeal traction that may benefit patients with obstructive sleep apnea. Here, we document endoscopic findings with ACS during drug-induced sleep endoscopy and additionally detail the effects of ACS on expiratory airflow, when the pharynx is known to be most hypotonic.

Obstructive Sleep Apnea: Non-positive Airway Pressure Treatments

Undiagnosed and untreated obstructive sleep apnea (OSA) is associated with health comorbidities and negatively affects quality of life. Alternative treatments should be considered in patients who are unable to tolerate or benefit from positive airway pressure treatment. When properly indicated, positional devices, oral appliances, airway surgery, and hypoglossal nerve stimulation have been shown to be effective in treating OSA. Hypoglossal nerve stimulation is a successful second-line treatment with low associated morbidity and complication rate.

Altered swallowing biomechanics in people with moderate-severe obstructive sleep apnea

STUDY OBJECTIVES

Dysphagia is a common but under-recognized complication of obstructive sleep apnea (OSA). However, the mechanisms remain poorly described. Accordingly, the aim of this study was to assess swallowing symptoms and use high-resolution pharyngeal manometry (HRPM) to quantify swallowing biomechanics in patients with moderate-severe OSA.

METHODS

Nineteen adults (4 female, mean age 46±26-68y) with moderate-severe OSA underwent HRPM testing with 5,10 & 20 ml volumes of thin and extremely thick liquids. Data were compared to 19 age- and sex-matched healthy controls (mean age 46±27-68y). Symptomatic dysphagia was assessed using the Sydney Swallow Questionnaire (SSQ). Swallow metrics were analyzed using the online application swallowgateway.com. General linear mixed model analysis was performed to investigate potential differences between people with moderate-severe OSA and controls. Data presented are means (95% CI).

RESULTS

26% (5/19) of the OSA group but none of the controls reported symptomatic dysphagia (SSQ>234). Compared to healthy controls, the OSA group had increased upper esophageal sphincter (UES) relaxation pressure (-2 [-1] vs. 2 [1]mmHg, F = 32.1, p <0.0001), reduced UES opening (6 vs. 5mS, F = 23.6, p<0.0001) and increased hypopharyngeal intrabolus pressure (2 [1] vs 7 [1]mmHg, F= 19.0, p <0.05). Additionally, upper pharyngeal pressures were higher, particularly at the velopharynx (88 [12] vs. 144 [12]mmHg.cm.s, F = 69.6, p<0.0001).

CONCLUSIONS

HRPM identified altered swallowing biomechanics in people with moderate-severe OSA, which is consistent with a subclinical presentation. Potential contributing mechanisms include UES dysfunction with associated upstream changes of increased hypopharyngeal distension pressure and velopharyngeal contractility.

Surgical, clinical, and functional outcomes of transoral robotic surgery used in sleep surgery for obstructive sleep apnea syndrome: A systematic review and meta-analysis

We investigated safety and efficacy of transoral robotic surgery (TORS) for base of tongue (BOT) reduction in obstructive sleep apnea syndrome (OSAS) patients. PubMed, Cochrane Library, and Scopus were searched. A meta-analysis was performed. Random effects models were used. Thirty-one cohorts met our criteria (1693 patients). The analysis was based mostly on retrospective studies. The summary estimate of the reduction of Apnea-Hypoxia Index (AHI) was 24.25 abnormal events per hour (95% CI: 21.69-26.81) and reduction of Epworth Sleepiness Scale (ESS) was 7.92 (95% CI: 6.50-9.34). The summary estimate of increase in lowest O₂ saturation was 6.04% (95% CI: 3.05-9.03). The success rate of TORS BOT reduction, either alone or combined with other procedures, was 69% (95% CI: 64-79). The majority of studies reported low level of evidence but suggested that TORS BOT reduction may be a safe procedure associated with improvement of AHI, ESS, and lowest O₂ saturation.

Can drug-induced sleep endoscopy (DISE) predict compliance with positive airway pressure therapy? A pilot study

PURPOSE

Drug-induced sleep endoscopy (DISE) has been poorly explored as an examination to assess positive airway pressure (PAP) therapy in patients with obstructive sleep apnea (OSA). The present study aimed to identify by DISE possible characteristics related to low compliance with PAP therapy due to respiratory complaints.

METHODS

Patients using PAP for OSA underwent DISE in two conditions: (1) baseline (without PAP) and (2) PAP (with the same mask and airway pressure used at home). We compared patients reporting low compliance to PAP due to respiratory complaints to those well-adapted to therapy. VOTE classification (assessment of velopharynx, oropharynx, tongue base, and epiglottis) and TOTAL VOTE score (the sum of VOTE scores at each anatomical site) were assessed. ROC curve analyzed the accuracy of TOTAL VOTE to predict low compliance due to persistent pharyngeal obstruction in both conditions.

RESULTS

Of 19 patients enrolled, all presented multilevel pharyngeal obstruction at baseline condition, with no difference between groups at this study point. When PAP was added, the median VOTE value was higher in the epiglottis (P value=0.02) and tended to be higher at the velum and tongue base in the poorly adapted group; TOTAL VOTE score was also significantly increased in patients with low compliance (P value<0.001). ROC curve demonstrated that patients with TOTAL VOTE scored 2.5 or more during DISE with PAP presented a 4.6-fold higher risk for low compliance with PAP therapy due to pharyngeal obstruction (AUC: 0.88±0.07; P value<0.01; sensitivity: 77%; specificity: 83%).

CONCLUSIONS

Adding PAP during a DISE examination may help to predict persistent pharyngeal obstruction during PAP therapy.

Can Machine Learning Assist Locating the Excitation of Snore Sound? A Review

In the past three decades, snoring (affecting more than 30 % adults of the UK population) has been increasingly studied in the transdisciplinary research community involving medicine and engineering. Early work demonstrated that, the snore sound can carry important information about the status of the upper airway, which facilitates the development of non-invasive acoustic based approaches for diagnosing and screening of obstructive sleep apnoea and other sleep disorders. Nonetheless, there are more demands from clinical practice on finding methods to localise the snore sound's excitation rather than only detecting sleep disorders. In order to further the relevant studies and attract more attention, we provide a comprehensive review on the state-of-the-art techniques from machine learning to automatically classify snore sounds. First, we introduce the background and definition of the problem. Second, we illustrate the current work in detail and explain potential applications. Finally, we discuss the limitations and challenges in the snore sound classification task. Overall, our review provides a comprehensive guidance for researchers to contribute to this area.

Orofacial Myofunctional Therapy in Obstructive Sleep Apnea Syndrome: A Pathophysiological Perspective

Obstructive sleep apnea (OSA) syndrome is a multi-factorial disorder. Recently identified pathophysiological contributing factors include airway collapsibility, poor pharyngeal muscle responsiveness, a low arousal threshold, and a high loop gain. Understanding the pathophysiology is of pivotal importance to select the most effective treatment option. It is well documented that conventional treatments (continuous positive airway pressure (CPAP), upper airway surgery, and dental appliance) may not always be successful in the presence of non-anatomical traits, especially in mild to moderate OSA. Orofacial myofunctional therapy (OMT) consists of isotonic and isometric exercises targeted to oral and oropharyngeal structures, with the aim of increasing muscle tone, endurance, and coordinated movements of pharyngeal and peripharyngeal muscles. Recent studies have demonstrated the efficacy of OMT in reducing snoring, apnea-hypopnea index, and daytime sleepiness, and improving oxygen saturations and sleep quality. Myofunctional therapy helps to reposition the tongue, improve nasal breathing, and increase muscle tone in pediatric and adult OSA patients. Studies have shown that OMT prevents residual OSA in children after adenotonsillectomy and helps adherence in CPAP-treated OSA patients. Randomized multi-institutional studies will be necessary in the future to determine the effectiveness of OMT in a single or combined modality targeted approach in the treatment of OSA. In this narrative review, we present up-to-date literature data, focusing on the role of OSA pathophysiology concepts concerning pharyngeal anatomical collapsibility and muscle responsiveness, underlying the response to OMT in OSA patients.

Expert Consensus Statement: Pediatric Drug-Induced Sleep Endoscopy

OBJECTIVE

To develop an expert consensus statement on pediatric drug-induced sleep endoscopy (DISE) that clarifies controversies and offers opportunities for quality improvement. Pediatric DISE was defined as flexible endoscopy to examine the upper airway of a child with obstructive sleep apnea who is sedated and asleep.

METHODS

Development group members with expertise in pediatric DISE followed established guidelines for developing consensus statements. A search strategist systematically reviewed the literature, and the best available evidence was used to compose consensus statements regarding DISE in children 0 to 18 years old. Topics with significant practice variation and those that would improve the quality of patient care were prioritized.

RESULTS

The development group identified 59 candidate consensus statements, based on 50 initial proposed topics, that focused on addressing the following high-yield topics: (1) indications and utility, (2) protocol, (3) optimal sedation, (4) grading and interpretation, (5) complications and safety, and (6) outcomes for DISE-directed surgery. After 2 iterations of the Delphi survey and removal of duplicative statements, 26 statements met the criteria for consensus; 11 statements were designated as no consensus. Several areas, such as the role of DISE at the time of adenotonsillectomy, were identified as needing further research.

CONCLUSION

Expert consensus was achieved for 26 statements pertaining to indications, protocol, and outcomes for pediatric DISE. Clinicians can use these statements to improve quality of care, inform policy and protocols, and identify areas of uncertainty. Future research, ideally randomized controlled trials, is warranted to address additional controversies related to pediatric DISE.

Post-Operative Sleep Endoscopy with Target-Controlled Infusion After Palatopharyngoplasty for Obstructive Sleep Apnea: Anatomical and Polysomnographic Outcomes

INTRODUCTION

The findings of drug-induced sleep endoscopy (DISE) are not always correlated with the outcome of upper airway surgery for obstructive sleep apnea (OSA), and whether multilevel surgery is truly required in treating multilevel obstruction identified in preoperative DISE remains an issue. We attempted to compare DISE findings before and after palatopharyngoplasty in patients with OSA because changes in DISE may be beneficial to better understand polysomnographic and anatomical outcomes.

METHODS

This was a prospective cohort study for 34 patients with moderate to severe OSA who underwent palatopharyngoplasty at a tertiary care center from 2016 to 2018. We recorded the patients' demographic characteristics, procedures, and surgical outcomes and compared the preoperative and postoperative DISE staging patterns.

RESULTS

The apnea-hypopnea index (AHI) values of 34 adults improved significantly after surgery (40.6 ± 23.3 versus 25.6 ± 20.6, P < 0.001). The majority of patients, 26/34, had preoperative complete concentric collapse at the velum, and for most (20/26, 77%) there was a change of the collapse pattern into anteroposterior collapse postoperatively. Patients with postoperative velar collapse had higher follow-up AHI values than those who without (27.8 ± 21.9 versus 15.2 ± 7.7, P = 0.023). Patients with preoperative complete tongue base collapse had higher follow-up AHI values than did those with no or partial collapse (40.6 ± 21.0 versus 21.0 ± 18.6, P = 0.017). Patients with postoperative complete tongue base collapse also had higher follow-up AHI values than the others (42.7 ± 22.1 versus 18.5 ± 15.4, P = 0.001).

CONCLUSION

Palatopharyngoplasty could change the collapse pattern at the velum in most patients. Preoperative and postoperative complete tongue base collapse and postoperative velar collapse identified in TCI-DISE were associated with relatively poor outcomes.

Effect of Modified Uvulopalatopharyngoplasty without Tonsillectomy on Obstructive Sleep Apnea: Polysomnographic Outcome and Correlation with Drug-Induced Sleep Endoscopy

OBJECTIVE

Uvulopalatopharyngoplasty (UPPP) is a common procedure for the treatment of obstructive sleep apnea (OSA) and is usually initiated with the resection of palatine tonsils. Because tonsillectomy potentially contributes to complications, minimally invasive upper airway surgeries have been proposed for OSA therapy. Whether tonsillectomy is always essential for UPPP remains unclear, particularly for patients with small tonsils. The purpose of this study was to present the effect of modified UPPP without tonsillectomy (UPsT) on patients with OSA and attempt to select the candidates for this procedure.

METHODS

This is a retrospective cohort study of patients with OSA, with tonsil size of grade 0-2, and with only retropalatal obstruction in drug-induced sleep endoscopy (DISE). The patients underwent UPsT at a tertiary center from November 2017 to December 2019. The sleep study was performed before and at least 3 months after surgery. The demographics, surgical outcomes, and staging patterns of preoperative DISE were recorded. The correlation between surgical outcome and DISE was also established.

RESULTS

A total of 22 adults with an average age of 46.5 years [interquartile range: 40 to 60 years] completed the follow-up study. Their apnea-hypopnea index (AHI) and Epworth sleepiness scale values improved significantly after surgery. Of the 17 patients with partial collapse and complete anteroposterior collapse (APC) at the velum, 16 presented good responses to UPsT. However, among the five patients with complete concentric collapse (CCC), only two (2/5, 40%) satisfied the criteria for surgical success. Furthermore, their follow-up AHI values were significantly higher than those of patients without CCC in DISE.

CONCLUSION

UPsT was demonstrated to be an effective therapy for patients with OSA who had small tonsils and retropalatal obstruction in DISE. CCC in sleep endoscopy indicates a poorer surgical outcome than does complete APC and partial collapse at the velum.

Effect of body weight on upper airway findings and treatment outcome in children with obstructive sleep apnea

OBJECTIVE/BACKGROUND

Surgical interventions for obstructive sleep apnea (OSA) are less effective in obese than in normal-weight children. However, the mechanisms that underpin this relationship are not fully understood. Therefore, this study aimed to explore how body weight influences upper airway collapse and treatment outcome in children with OSA.

METHODS

We conducted a retrospective analysis of prospectively collected data on polysomnography, drug-induced sleep endoscopy (DISE), and treatment outcome in otherwise healthy children with OSA. Associations between body mass index (BMI) z-score and upper airway collapse during DISE were assessed using logistic regression modelling. Treatment success was defined as obstructive apnea-hypopnea index (oAHI) < 5 events/hour and cure as oAHI < 2 events/hour with obstructive apnea index < 1 event/hour.

RESULTS

A total of 139 children were included [median (Q1─Q3); age 4.5 (3.1─8.4) years; BMI z-score 0.3 (-0.8 to 1.4); oAHI 10.8 (6.8─18.0) events/hour]. Twenty-five of them were overweight and 21 were obese. After adjusting for age and history of upper airway surgery, BMI z-score was significantly correlated with circumferential upper airway collapse during DISE (odds ratio 1.67; 95% confidence interval 1.12─2.65; P = 0.011). Outcome of DISE-directed treatment was similar in normal-weight (success: 91.4%; cure: 78.5%), overweight (success: 88.0%; cure: 80.0%), and obese (success: 90.5%; cure: 76.5%) children. Children with circumferential collapse responded better to continuous positive airway pressure than to (adeno)tonsillectomy.

CONCLUSION

Increasing body weight is associated with circumferential upper airway collapse during DISE and, accordingly, may require treatment strategies other than (adeno)tonsillectomy.