Prediction of Epiglottic Collapse in Obstructive Sleep Apnea Patients: Epiglottic Length

Lateral epiglottic collapse in obstructive sleep apnea is associated with laterally directed pharyngeal collapse

STUDY OBJECTIVES

Epiglottic collapse can obstruct the airway in patients with obstructive sleep apnea in an anteroposterior or lateral direction. The present study investigates the concept that lateral or concentric pharyngeal collapse patterns may remodel the epiglottis and predispose it to lateral collapse. To do so, we hypothesized that the presence of-any form of laterally directed pharyngeal collapse, eg, oropharyngeal lateral wall collapse or complete concentric collapse of the soft palate, is associated with increased odds for having concurrent lateral epiglottic collapse (E-lat).

METHODS

We analyzed 582 patients with obstructive sleep apnea from our drug-induced sleep endoscopy cohort. Site of collapse was scored by a single scorer using the VOTE criteria, with patients with epiglottic collapse reviewed by 2 additional independent scorers. Logistic regression evaluated the association between presence of laterally directed pharyngeal collapse and the presence of E-lat.

RESULTS

The overall prevalence of E-lat was 2.6% (n = 15). The presence of any form of laterally directed pharyngeal collapse was associated with 4-fold increased odds (4.4 [1.5-12.6], P = .006) of having concurrent E-lat. Further, the specific presence of either complete oropharyngeal lateral wall collapse or complete concentric collapse of the soft palate was associated with an odds ratio of 3.4 [1.2-9.6] and 8.6 [2.2-33.5], respectively, of having concurrent E-lat.

CONCLUSIONS

Greater prevalence of severe laterally directed pharyngeal collapse, in the form of either complete concentric collapse of the soft palate or oropharyngeal lateral wall collapse in patients with E-lat supports the concept that laterally and concentric pharyngeal collapse patterns may shape the epiglottis and thereby contribute to the pathogenesis of E-lat.

CITATION

Wang T-Y, Huyett P, Yang H, et al. Lateral epiglottic collapse in obstructive sleep apnea is associated with laterally directed pharyngeal collapse. J Clin Sleep Med. 2025;21(4):649-654.

3D morphometric analysis of the epiglottis using CBCT: age and gender differences

BACKGROUND

This study aimed to perform a comprehensive morphometric analysis of the epiglottis using cone-beam computed tomography (CBCT) images, including the determination of epiglottis dimensions, the investigation of shape variations, and the assessment of their relationship with gender and age.

METHODS

A retrospective analysis was conducted on high-quality CBCT images from 100 patients, obtained using the NewTom 5G system. In CBCT images, epiglottis thicknesses (right, midline, left) and horizontal angle at three levels (suprahyoid, hyoid, infrahyoid) were measured in axial sections, while the length and vertical angle of epiglottis were measured in midsagittal view. Epiglottis shapes were identified through 3D visualization.

RESULTS

The midline epiglottis thicknesses were 4.68 mm at the suprahyoid level, 5.51 mm at the hyoid level, and 6.80 mm at the infrahyoid levels. Epiglottis thicknesses and length were statistically significantly greater in males. Of the 100 patients, 51 had a normal curvature, 41 had a flat epiglottis, and 8 had an omega epiglottis. The omega-shaped epiglottis was significantly longer compared to both the flat and normal curvature types (p = 0.011). There was a positive correlation between age and epiglottis thicknesses at the suprahyoid level and horizontal angles at three levels.

CONCLUSIONS

This study visualizes epiglottis morphology and uncovers significant morphometric differences. Males exhibit greater epiglottis thickness and length compared to females, while the omega-shaped epiglottis is notably longer than other types. These findings underscore the need for further investigation into the clinical relevance of these morphometric differences, particularly in improving airway management and refining approaches to swallowing function.

Sleep apnea patients with epiglottic collapse elevate their larynx more with swallowing; videofluoroscopic swallowing study of 80 patients

OBJECTIVE

The epiglottis plays an integral role in the swallowing mechanism and is also implicated as an obstruction site in obstructive sleep apnea (OSA). The underlying causes of epiglottic collapse during sleep remain unclear. This study aimed to investigate the cognitive functions using the Loewenstein Occupational Therapy Cognitive Assessment (LOTCA) and the neurophysiological and anatomical factors using videofluoroscopic swallowing studies (VFSS). We compared patients with OSA exhibiting epiglottic collapse to those without, assessing differences in anatomical or neurophysiological characteristics.

METHODS

The study included 12 patients with epiglottic collapse (Epi-group) and 68 without (non-Epi group), all undergoing overnight polysomnography (PSG), drug-induced sleep endoscopy (DISE), LOTCA, and VFSS. Oral transit time (OTT), pharyngeal delay time (PDT), and pharyngeal transit time (PTT) were considered as neurophysiological traits, and laryngeal elevation length (LE) as anatomical trait, and were measured across various test diets (10 ml of liquid, soft, or solid).

RESULTS

The study comprised 80 individuals, 57 men and 23 women, with no significant age, sex, body mass index or PSG parameters between groups, or DISE findings, with the exception of epiglottic collapse. Swallowing metrics from VFSS were normal, with no differences in OTT, PDT, PTT, or LOTCA scores. Notably, patients with epiglottic collapse showed a greater laryngeal elevation when swallowing soft and solid foods (p = 0.025 and p = 0.048, respectively).

CONCLUSIONS

Patients with epiglottic collapse do not exhibit neurophysiological or cognitive impairments when compared to non-Epi group. However, the Epi-group displayed a significantly increased laryngeal elevation length. This suggests that anatomical factors may have a more substantial role in the development of epiglottic collapse than neurophysiological factors.

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.

Potential Treatments for Epiglottic Collapse in Obstructive Sleep Apnea: How Modified Drug-Induced Sleep Endoscopy Help?

OBJECTIVE

In patients with obstructive sleep apnea (OSA), epiglottic collapse (EC) constitutes a major factor in the failure of continuous positive airway pressure therapy and uvulopalatopharyngoplasty. This study explored treatments that can improve EC in patients with OSA through drug-induced sleep endoscopy with target-controlled infusion (TCI-DISE).

STUDY DESIGN

Retrospective cohort study.

SETTING

Tertiary center.

METHODS

This study screened 352 OSA patients who underwent TCI-DISE between 2016 and 2022. Fifty-four patients with EC were included in the final analysis. EC severity was assessed multiple times through TCI-DISE with different interventions.

RESULTS

The application of these interventions in patients with anteroposterior epiglottic collapse (apEC) led to a significant decrease in apEC severity from total to partial or no obstruction in 60.0% of patients by head rotation, in 53.6% by mouth closure, in 47.4% who received oral appliances (OA), and in 28.0% who received intermittent negative airway pressure (iNAP). With simultaneous head rotation, apEC severity decreased more significantly from total to partial or no obstruction in 77.8% of patients by mouth closure, in 70.3% who received OA, and in 68.0% who received iNAP. Lateral epiglottic collapse (latEC) severity decreased in 53.8% of patients after OA use and in 61.5% of patients with OA use and head rotation.

CONCLUSION

This study identified head rotation with mouth closure as the most effective treatment for apEC through TCI-DISE. Patients with latEC had higher weight, apnea-hypopnea index, and body mass index compared with patients with apEC. OA use with head rotation appeared more effective in latEC through TCI-DISE.

Arytenoid Cartilage Collapse During Inhalation in Awake Patients with Intermediate/High Risk of Obstructive Sleep Apnea: A Retrospective Analysis of Sixty-Four Patients

OBJECTIVE

To assess the prevalence of arytenoid cartilage collapse (ACC) during deep inhalation in awake patients with intermediate/high risk of obstructive sleep apnea (OSA).

STUDY DESIGN

Retrospective case-control study.

METHODS

The medical records and video recordings of awake flexible endoscopic examination of patients with history of OSA who presented to the sleep apnea clinic in a tertiary referral medical center between June 2022 and December 2022, were reviewed. All patients had filled the STOP-BANG questionnaire and had intermediate/high risk of having OSA. A group of patients matched by age and gender and with no history of OSA were used as controls.

RESULTS

A total of 95 patients, 64 with a history of OSA and 31 with no history of OSA, were included. Among the study group, 37.5% (n = 24) had a STOP-BANG score between 3 and 4 and were considered to be at an intermediate risk of OSA while the remaining had a score more than 5 and were considered to be at high risk of OSA. There was a significant difference in the prevalence of ACC between the study group and controls (32.8% vs 12.9%, respectively, P < 0.001).

CONCLUSION

The prevalence of ACC was significantly higher in patients with intermediate/high risk of OSA in comparison to healthy controls with no history of OSA. When present, ACC should raise the physician's suspicion for OSA and probably prompt further investigation such as a sleep study.

Treatment of a floppy epiglottis with upper airway stimulation therapy

PURPOSE

To evaluate the efficacy of upper airway stimulation therapy in patients with a floppy epiglottis who have experienced continuous positive airway pressure failure or intolerance.

METHODS

A retrospective single-center cohort study was conducted. Patients who received an Inspire Upper Airway Stimulation system and had a 1-year follow-up were included. Baseline and one-year in-laboratory polysomnography examinations were performed. Patient characteristics, Epworth Sleepiness Scale scores and upper airway stimulation device settings were collected.

RESULTS

A total of 75 patients were included, of whom 10 had a floppy epiglottis. Patients with a floppy epiglottis had a significant therapeutic response to upper airway stimulation therapy, similar to patients without a floppy epiglottis. According to the Sher's success criteria, 90% of patients with a floppy epiglottis and 68% of patients without a floppy epiglottis were responders to therapy (p = 0.149). In the floppy epiglottis group, the apnea-hypopnea index decreased from 35.1 ± 5.5 events/hour to 11.2 ± 11.3 events/hour (95% CI (15.0, 32.9), p < 0.001), similarly in the non-floppy epiglottis group, the decline was from 36.4 ± 8.3 events/hour to 14.4 ± 9.5 events/hour (95% CI (18.6, 25.2), p < 0.001, between groups p = 0.659). Comparable reductions were observed for the other respiratory parameters.

CONCLUSION

Treatment of patients with obstructive sleep apnea and a floppy epiglottis can be challenging. Continuous positive airway pressure may aggravate the epiglottis collapse. Upper airway stimulation therapy can be considered an effective alternative treatment option for patients with a floppy epiglottis who have encountered either continuous positive airway pressure failure or intolerance.

Relationship between level CPAP titration, anthropometric variables, and drug-induced sleep endoscopy DISE

INTRODUCTION

Subjects with palatal obstruction alone vs. multilevel obstruction on DISE had better outcomes after palate surgery. We asked ourselves if the therapeutic level positive airway pressure (PAP) titration could predict the level of airway obstruction and its complexity.

PURPOSE

The aim of this study was to identify possible relationships between therapeutic level of positive airway pressure initial titration and levels of collapse in drug-induced sleep endoscopy (DISE). A secondary objective was to establish the relationship the other variables and DISE.

METHODS

We analyzed retrospective clinical histories between March 2020 to March 2022 of 37 patients with polysomnography or cardiorespiratory polygraphy studies and PAP initial titration who were taken to drug-induced sleep endoscopy. Sleep study data, anthropometric variables, and patterns of airway collapse during DISE were analyzed with PAP initial titration levels.

RESULTS

Most of the patients with complex collapse had concentric velum collapse (p < 0.006). A significant association was found between the apnea-hypopnea index (AHI) and oropharyngeal collapse; (p < 0.0030) and finally we demonstrated relationship between neck circumference and gender with epiglottis collapse (p < 0.046), (p < 0.037), respectively.

CONCLUSIONS

Our findings show a strong relationship between that complex collapses and concentric velum collapse; patients with greater oropharyngeal collapse have a higher mean AHI. Patients without epiglottic collapse have a higher mean neck circumference. An association between mean pressure initial titration and complex collapse could not be established.

Surgical Treatment Options for Epiglottic Collapse in Adult Obstructive Sleep Apnoea: A Systematic Review

The critical role of epiglottis in airway narrowing contributing to obstructive sleep apnoea (OSA) and continuous positive airway pressure (CPAP) intolerance has recently been revealed. This systematic review was conducted to evaluate available surgical treatment options for epiglottic collapse in adult patients with OSA. The Pubmed and Scopus databases were searched for relevant articles up to and including March 2022 and sixteen studies were selected. Overall, six different surgical techniques were described, including partial epiglottectomy, epiglottis stiffening operation, glossoepiglottopexy, supraglottoplasty, transoral robotic surgery, maxillomandibular advancement and hypoglossal nerve stimulation. All surgical methods were reported to be safe and effective in managing selected OSA patients with airway narrowing at the level of epiglottis. The surgical management of epiglottic collapse can improve OSA severity or even cure OSA, but can also improve CPAP compliance. The selection of the appropriate surgical technique should be part of an individualised, patient-specific therapeutic approach. However, there are not enough data to make definitive conclusions and additional high-quality studies are required.

Patients with Epiglottic Collapse Are Less Adherent to Autotitrating Positive Airway Pressure Therapy for Obstructive Sleep Apnea

Rationale: The anatomic orientation of the epiglottis is such that it points in the opposite direction to inspiratory flow, thereby potentially making positive airway pressure (PAP) treatment challenging in patients with epiglottic collapse. However, no previous studies have analyzed PAP adherence in these patients. Objectives: This study aimed to analyze adherence to autotitrating PAP (APAP) treatment in patients with epiglottic collapse. Methods: We performed an age- and sex-matched case-control study. On the basis of their overnight level-I polysomnogram, patients were prescribed APAP in a tertiary hospital between July 2018 and March 2019. The site of airway collapse was diagnosed with drug-induced sleep endoscopy. Demographic factors, sleep questionnaire, polysomnography, and APAP usage statistics were analyzed. Results: Eighteen patients with epiglottic collapse (epi-group) and 36 without epiglottic collapse (control group) were analyzed. We found that 22.8% of patients in the epi-group terminated APAP within 2 weeks, whereas only 2.8% of patients in the control group terminated APAP within 2 weeks (P = 0.048). The percentage of days with usage over 4 hours was significantly lower in the epi-group (64.6% vs. 75.6%; P = 0.008). In addition, the adherence failure rate was 66.7% in the epi-group and 33.3% in the control group (P = 0.039). Patients with epiglottic collapse were also found to have lower body mass index, which is an unfavorable predictor of APAP adherence. Conclusions: This study suggests that patients with epiglottic collapse have a higher APAP adherence failure rate than patients without epiglottic collapse. Thus, patients with epiglottic collapse should be followed closely during treatment, and alternative therapies should probably be considered for these patients.

Obstructive Sleep Apnea and Role of the Diaphragm

Obstructive sleep apnea (OSA) causes multiple local and systemic pathophysiological consequences, which lead to an increase in morbidity and mortality in patients suffering from this disorder. OSA presents with various nocturnal events of apnoeas or hypopneas and with sub-clinical airflow limitations during wakefulness. OSA involves a large percentage of the population, particularly men, but the estimate of OSA patients could be much broader than data from the literature. Most of the research carried out in the muscle field is to understand the causes of the presence of chronic nocturnal desaturation and focus on the genioglossus muscle and other muscles related to dilating the upper airways. Sparse research has been published regarding the diaphragm muscle, which is the main muscle structure to insufflate air into the airways. The article reviews the functional anatomy of the muscles used to open the upper respiratory tract and the non-physiological adaptation that follows in the presence of OSA, as well as the functional anatomy and pathological adaptive aspects of the diaphragm muscle. The intent of the text is to highlight the disparity of clinical interest between the dilator muscles and the diaphragm, trying to stimulate a broader approach to patient evaluation.