How does open-mouth breathing influence upper airway anatomy?

Strengthening oropharyngeal muscles as an approach to treat post-stroke obstructive sleep apnea: A feasibility randomised controlled trial

This study aimed to determine the feasibility of a randomised controlled trial (RCT) evaluating oropharyngeal exercise (OPE) intervention as an alternative therapy for obstructive sleep apnea (OSA) in patients with stroke or transient ischaemic attack (TIA). Despite the high prevalence of OSA in this population, the standard therapy, continuous positive airway pressure (CPAP), is often poorly tolerated. Thirty stroke/TIA patients with OSA unable to tolerate CPAP were randomly assigned to an oropharyngeal exercise or sham exercise protocol. They performed exercises for 6 weeks, 5 days per week, 30 minutes twice per day. Feasibility was ascertained by the proportion of enrolled patients who completed more than 80% of the OPE regimen. Isometric tongue pressures, apnea-hypopnea index (AHI), oxygen desaturation index (ODI), daytime sleepiness, and quality of life (QOL) outcomes were collected at baseline, post-training (6-week follow-up), and retention (10-week follow-up) to document preliminary efficacy. Adherence to study exercises was excellent, with 83% of participants completing more than 80% of the exercises. The isometric tongue pressures were observed to improve in the oropharyngeal exercise group (compared with the sham group), along with a decrease in OSA severity (measured by the AHI and ODI), reduced daytime sleepiness, and enhanced quality of life outcomes following the exercise programme. Only the effects on posterior isometric tongue pressure and daytime sleepiness remained significantly different between groups at the retention session. In conclusion, an RCT evaluating the efficacy of oropharyngeal exercises on post-stroke/TIA OSA is feasible and our preliminary results suggest a clinically meaningful effect.

Analysis of maxillary arch morphology and its relationship with upper airway in mouth breathing subjects with different sagittal growth patterns

OBJECTIVE

This three-dimensional cone beam computed tomography(CBCT) study assessed pharyngeal airway and maxillary arch in mouth breathing subjects with different skeletal classifications and analyzed the factors associated with the upper airway morphological variations in mouth breathing (MB) and nasal breathing (NB) subjects.

METHODS

One hundred and five subjects (52 MB and 53 NB children), divided into three skeletal groups: Class I (1° ≤ ANB° ≤ 5°), Class II (ANB° >5°), and Class III (ANB°<1°). An independent t-test and one-way ANOVA test were utilized in the group analysis of normal distributed data. The linear multiple regression test was applied to create a model for the airway volumes based on the maxillary arch parameters in different skeletal groups.

RESULTS

In three skeletal groups, NB individuals had greater oropharyngeal airway volume (OPV) and total pharyngeal airway volume (TPV) than MB. Maxillary arch parameters of intermolar width (IMW), intercanine width (ICW), and maxillary width of canines (MWC) were larger in NB participants than in MB subjects. In the MB group, we discovered that Class II individuals had lower NPV (nasopharyngeal airway volume) than Class I and Class III. MWC was lower in Class II subjects compared to Class I and Class III in both the NB and MB groups.

CONCLUSION

NB individuals had greater pharyngeal airway and maxillary arch parameters than MB subjects. Our model equation revealed that the inter-molar width (IMW) and palatal area (PA) parameters were the strongest predictors of total pharyngeal airway volume (TPV) in the skeletal Class II and Class I groups.

The Impact of Mouth-Taping in Mouth-Breathers with Mild Obstructive Sleep Apnea: A Preliminary Study

Background: Many patients with obstructive sleep apnea (OSA) are mouth-breathers. Mouth-breathing not only narrows the upper airway, consequently worsening the severity of OSA, but also it affects compliance with nasal continuous positive airway pressure (CPAP) treatment. This study aimed to investigate changes in OSA by the use of mouth tape in mouth-breathers with mild OSA. Method: Mouth-breathers with mild OSA who met inclusion criteria and tolerated the sealing of the mouth were enrolled in the study. We used 3M silicone hypoallergenic tape was used to seal the mouths of the participants during sleep. The home sleep test (HST) used in this study was ApneaLink^®. Subjects received both a baseline HST and an outcome HST to be used 1 week later while their mouths were taped. The changes between the baseline and the outcome HSTs were compared, and the factors that influenced the differences in the sleep-test parameters after the shift of the breathing route were analyzed. A “responder” was defined as a patient who experienced a reduction from the baseline snoring index of at least 50% under mouth-taping in the HST; otherwise, patients were considered as having a poor response. Results: A total of 20 patients with mild OSA were included. Following the taping of the mouth, a good response was found in 13 patients (65%). The median apnea/hypopnea index (AHI) decreased significantly, from 8.3 to 4.7 event/h (by 47%, p = 0.0002), especially in supine AHI (9.4 vs. 5.5 event/h, p = 0.0001). The median snoring index (SI) was also improved (by 47%, 303.8 vs. 121.1 event/h, p = 0.0002). Despite no significant difference in the mean saturation, improvements in the oxygen desaturation index (8.7 vs. 5.8, p = 0.0003) and the lowest saturation (82.5% vs. 87%, p = 0.049) were noted. The change in AHI was associated with baseline AHI (r = −0.52, p = 0.02), oxygen desaturation index (ODI) (r = −0.54, p = 0.01), and SI (r = −0.47, p = 0.04). The change in SI was strongly associated with baseline SI (r = −0.77, p = 0.001). Conclusions: Mouth-taping during sleep improved snoring and the severity of sleep apnea in mouth-breathers with mild OSA, with AHI and SI being reduced by about half. The higher the level of baseline AHI and SI, the greater the improvement was shown after mouth-taping. Mouth-taping could be an alternative treatment in patients with mild OSA before turning to CPAP therapy or surgical intervention.

Obstructive sleep apnea: personalizing CPAP alternative therapies to individual physiology

Introduction The recent continuous positive airway pressure (CPAP) crisis has highlighted the need for alternative obstructive sleep apnea (OSA) therapies. This article serves to review OSA pathophysiology and how sleep apnea mechanisms may be utilized to individualize alternative treatment options.Areas covered: The research highlighted below focuses on 1) mechanisms of OSA pathogenesis and 2) CPAP alternative therapies based on mechanism of disease. We reviewed PubMed from inception to July 2022 for relevant articles pertaining to OSA pathogenesis, sleep apnea surgery, as well as sleep apnea alternative therapies.Expert opinion: Although the field of individualized OSA treatment is still in its infancy, much has been learned about OSA traits and how they may be targeted based on a patient's physiology and preferences. While CPAP remains the gold-standard for OSA management, several novel alternatives are emerging. CPAP is a universal treatment approach for all severities of OSA. We believe that a personalized approach to OSA treatment beyond CPAP lies ahead. Additional research is needed with respect to implementation and combination of therapies longitudinally, but we are enthusiastic about the future of OSA treatment based on the data presented here.

Three-dimensional evaluation of pharyngeal airway and maxillary arch in mouth and nasal breathing children with skeletal Class I and II

OBJECTIVE

This study aimed to investigate whether the subjects with mouth breathing (MB) or nasal breathing (NB) with different sagittal skeletal patterns showed different maxillary arch and pharyngeal airway characteristics.

METHODS

Cone-beam computed tomography scans from 70 children aged 10 to 12 years with sagittal skeletal Classes I and II were used to measure the pharyngeal airway, maxillary width, palatal area, and height. The independent t-test and the Mann-Whitney U test were used for the intragroup analysis of pharyngeal airway and maxillary arch parameters.

RESULTS

In the Skeletal Class I group, nasopharyngeal airway volume (P < 0.01), oropharyngeal airway volume (OPV), and total pharyngeal airway volume (TPV) (all P < 0.001) were significantly greater in subjects with NB than in those with MB. Furthermore, intermolar width, maxillary width at the molars, intercanine width, maxillary width at the canines, and palatal area were significantly larger in subjects with NB than in those with MB (all P < 0.001). In the Skeletal Class II group, OPV, TPV (both P < 0.05) were significantly greater in subjects with NB than in those with MB. No significant differences in pharyngeal airway parameters in the MB group between subjects with Skeletal Class I and those with Skeletal Class II.

CONCLUSION

Regardless of sagittal Skeletal Class I or II, the pharyngeal airway and maxillary arch in children with MB differ from those with NB. However, the pharyngeal airway was not significantly different between Skeletal Class I and II in children with MB.

Volumetric Changes after Coblation Ablation Tongue (CAT) in Obstructive Sleep Apnea Patients

Background: Obstruction of the tongue is commonly seen in patients with obstructive sleep apnea (OSA). This study proposed whole tongue treatment using coblation ablation tongue (CAT) and aimed to explore the potential association between the dimensions of a tongue and the severity of OSA, to inspect volumetric changes of the tongue after CAT, and to search for factors that influence outcome of tongue volume change. Methods: The prospective study enrolled 12 OSA patients (all male, average age: 35 years, average apnea/hypopnea index (AHI): 45.5 event/h, average body mass index (BMI): 27.0 kg/m²). All patients received multi-level sleep surgery including septomeatoplasty, uvulopalatopharyngoplasty, and CAT. The CAT used a coblation wand to perform uniform multiple ablations (15 points, body −6, base −9) on dorsal tongue. Three dimensions of the tongue (length, height, and width) and tongue volume were measured from head and neck computed tomography. The perioperative changes in the tongue dimension/volume and AHI were assessed at baseline and 3 months after surgery. Result: The baseline tongue length and AHI had a significant correlation (r = 0.60, p = 0.02). The multi-level surgery significantly improved AHI (43.8 vs. 23.7, p = 0.008). The CAT significantly decreased tongue volume from 91.3 to 85.6 cm³ (p = 0.02), with an average tongue volume reduction of 5.7 cm³ per person and 0.38 cm³ per ablation. Further outcome analysis showed surgical success was significantly higher in patients with non-hypertrophic lingual tonsils (grade I/II) than in those with hypertrophic lingual tonsils (grade III/IV) (p = 0.02). Conclusion: Length of the tongue is associated with the severity of OSA. The CAT significantly decreased the tongue volume in OSA patients. A volumetric reduction of 0.38 cm³ per ablation could be useful in the optimal reduction of tongue for OSA. The CAT significantly enlarged the retroglossal airway volume, which is related to the non-hypertrophic lingual tonsil.

Detection of Sleep-Disordered Breathing in Patients with Spinal Cord Injury Using a Smartphone

Patients with spinal cord injury (SCI) have an increased risk of sleep-disordered breathing (SDB), which can lead to serious comorbidities and impact patients’ recovery and quality of life. However, sleep tests are rarely performed on SCI patients, given their multiple health needs and the cost and complexity of diagnostic equipment. The objective of this study was to use a novel smartphone system as a simple non-invasive tool to monitor SDB in SCI patients. We recorded pulse oximetry, acoustic, and accelerometer data using a smartphone during overnight tests in 19 SCI patients and 19 able-bodied controls. Then, we analyzed these signals with automatic algorithms to detect desaturation, apnea, and hypopnea events and monitor sleep position. The apnea–hypopnea index (AHI) was significantly higher in SCI patients than controls (25 ± 15 vs. 9 ± 7, p < 0.001). We found that 63% of SCI patients had moderate-to-severe SDB (AHI ≥ 15) in contrast to 21% of control subjects. Most SCI patients slept predominantly in supine position, but an increased occurrence of events in supine position was only observed for eight patients. This study highlights the problem of SDB in SCI and provides simple cost-effective sleep monitoring tools to facilitate the detection, understanding, and management of SDB in SCI patients.

The Importance of Mask Selection on Continuous Positive Airway Pressure Outcomes for Obstructive Sleep Apnea. An Official American Thoracic Society Workshop Report

Continuous positive airway pressure (CPAP) remains the major treatment option for obstructive sleep apnea (OSA). The American Thoracic Society organized a workshop to discuss the importance of mask selection for OSA treatment with CPAP. In this workshop report, we summarize available evidence about the breathing route during nasal and oronasal CPAP and the importance of nasal symptoms for CPAP outcomes. We explore the mechanisms of air leaks during CPAP treatment and possible alternatives for leak control. The impact of nasal and oronasal CPAP on adherence, residual apnea-hypopnea index, unintentional leaks, and pressure requirements are also compared. Finally, recommendations for patient and partner involvement in mask selection are presented, and future directions to promote personalized mask selection are discussed.

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 Between Breathing Route, Oxygen Desaturation, and Upper Airway Morphology

OBJECTIVES/HYPOTHESIS

This study aimed to assess the role of capnography in objectively evaluating breathing routes during drug-induced sleep endoscopy (DISE) and further elucidate the relationship between breathing route, obstructive sleep apnea (OSA) severity, and DISE findings.

STUDY DESIGN

Prospective observational study.

METHODS

Nighty-five patients with established OSA were recruited for this study from May 2017 to May 2019. DISE was performed in the operating room. Sedation was maintained with propofol using a target-controlled infusion system and the depth of sedation was monitored based on the bispectral index. The breathing routes, which included oral breathing, oronasal breathing, and nasal breathing, were detected using capnography. DISE findings were recorded using the VOTE (velum, oropharynx, base of tongue, and epiglottis) classification.

RESULTS

Patients with mouth breathing were associated with increased OSA severity, worse oximetric variables, and higher body mass index in comparison with those with other breathing routes. Mouth breathing was associated with a higher degree and higher prevalence of lateral pharyngeal wall collapse and tongue base collapse during DISE.

CONCLUSIONS

Mouth breathing was significantly associated with worse oxygen desaturation and increased degree of upper airway collapse. Therefore, patients with mouth breathing during propofol-based intravenous anesthesia should be carefully monitored.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E659-E664, 2021.

Mandibular movement analisys by means of a kinematic model applied to the design of oral appliances for the treatment of obstructive sleep apnea

BACKGROUND

Mandibular advancement devices (MADs) are one of the treatment options used for the obstructive sleep apnea syndrome (OSAS). At present, MADs are designed with standard titration systems, without considering each patient's anatomical characteristics of the temporomandibular joint and mandible shape. The main objective of this study is to evaluate if a variability in mandibular morphology will influence the displacement of the jaw with a MAD. Such knowledge will be of help to find optimal mandibular positions with MAD even when opening the mouth.

METHODS

By using a mandibular movement model, the movement patterns of different points on the chin have been analyzed. The influence of different skeletal mandibular shapes on these movements have also been studied. The results show differences in the movement patterns of the lower front teeth depending on its distance to the center of the condyle, with a more horizontal direction in those in which there is a greater distance.

RESULTS

Variations in mandibular morphology imply differences in movement patterns of the analyzed points of the mandible. Consequently, MADs should be designed according to each patient's anatomy to avoid mandibular retrusion in those areas that may narrow the upper airways.

CONCLUSIONS

This study may help to understand why not all patients move their lower jaws forwards equally with the same degree of mandibular protrusion measured in relation to the teeth. These results might also partially explain why airway obstruction is more severe in certain untreated sleep apnea subjects than in others when opening their mouth during sleep.

Assessment of obstructive sleep apnoea (OSA) in children: an update

OSA is a condition characterised by episodes of complete or partial obstruction of the upper airway, associated with blood-gas changes and atypical sleep patterns. Early diagnosis of OSA may reduce the occurrence of systemic complications over time, although the diagnosis of OSA is, unfortunately, often late. The aim of the work is to review the current concepts in evaluation of paediatric obstructive sleep apnoea (OSA), with an updated revision of the literature considering risk factors, clinical manifestations, and basic and advanced assessment in the paediatric population. For this narrative review, PubMed, Embase and Cinahl databases were searched for the last 10 years, according to PRISMA criteria/guidelines. Assessment of paediatric OSA remains challenging and paediatric patients should always be carefully evaluated; polysomnography is the gold standard for diagnosis of paediatric OSA.

Effect of mouth closure on upper airway obstruction in patients with obstructive sleep apnoea exhibiting mouth breathing: a drug-induced sleep endoscopy study

PURPOSE

Snoring and obstructive sleep apnoea (OSA) exhibit multifactorial aetiologies; mouth breathing increases airway obstruction and upper respiratory tract resistance. Of the many published studies, few have evaluated sleeping subjects. We explored how mouth breathing affected the upper respiratory tract anatomy and OSA during sleep.

METHODS

Eighteen patients with OSA, confirmed via full-night polysomnography, were enrolled in this study. We performed drug-induced sleep endoscopy (DISE) and defined obstruction sites before and after mouth closure using commercial mouth strips. We evaluated obstruction sites in two ways, i.e. by grading obstructions using our DISE grading system and measuring the affected areas. Patients who improved by at least one DISE grade were defined as responders. Areas were measured based on DISE videos analysed using ImageJ software. The apnoea-hypopnoea index (AHI) and body mass index (BMI) were recorded.

RESULTS

Based on the DISE grade, 40% (7/18) of patients showed obstruction site improvement. When assessed areally, the mean number of pixels improved significantly at both the retropalatal (p = 0.045) and retrolingual (p = 0.019) levels. However, DISE non-responders exhibited no areal improvements. Responders and non-responders did not differ significantly in terms of AHI or BMI (both p < 0.05).

CONCLUSIONS

Mouth closure improves or at least does not lead to further deterioration of the upper airway. Improvements were evident at the retropalatal and especially retrolingual levels. Neither the BMI nor the AHI differed between the two groups. However, responders tended to have a higher AHI than non-responders (39.4 vs. 32.8 events/h).

Oral dysfunction as a cause of malocclusion

This narrative review surveys current research demonstrating how oral dysfunction can escalate into malocclusion, acquired craniofacial disorder and contribute to generational dysfunction, disorder and disease.

INTRODUCTION

Baseline orthodontic consultations are generally recommended beginning age seven. However, the dysmorphic changes that result in malocclusion are often evident years earlier. Similarly, following orthodontic treatment, patients require permanent retention when the bite is not stable, and without such retention, the malocclusion can return.

SETTING AND POPULATION

Narrative review article including research on infants, children and adults.

MATERIALS AND METHODS

This review is a brief survey of the symptomology of orofacial myofunctional disorder and outlines 10 areas of oral function that impact occlusal and facial development: breastfeeding, airway obstruction, soft tissue restriction, mouth breathing, oral resting posture, oral habits, swallowing, chewing, the impact of orofacial myofunctional disorder (OMD) over time and maternal oral dysfunction on the developing foetus.

CONCLUSION

Malocclusions and their acquired craniofacial dysmorphology are the result of chronic oral dysfunction and OMD. In order to achieve long-term stability of the face, it is critical to understand the underlying pathologies contributing to malocclusion, open bite and hard palate collapse.

Evaluation of sleep quality and risk of obstructive sleep apnea in patients referred for aesthetic rhinoplasty

Importance

Aesthetic rhinoplasty is the fifth surgical procedure most performed worldwide by plastic surgeons. With the growing demand for rhinoplasty, there is an unmet need for research into the profile of patients who seek aesthetic nasal surgery in an attempt to improve not only cosmetic dissatisfactions, but also the manifestations of other, possibly interrelated disorders, especially sleep disturbances.

Objective

To evaluate the sleep quality and the risk of Obstructive Sleep Apnea in patients referred for aesthetic rhinoplasty, as well as the association of these conditions with nasal symptoms. Design: Cross-sectional study performed at the period of June/2016 to August/2017. Setting: Department of Otolaryngology and Head and Neck Surgery - Universidade Federal de São Paulo. Participants: Patients of both sexes, aged 18 to 65 years, who were referred for aesthetic rhinoplasty. We evaluated 46 patients, two of whom were excluded because they were outside the inclusion age criteria. Main Outcome(s) and Measure(s): Anterior rhinoscopy and the following validated surveys were used. Pittsburgh Sleep Quality Index; Epworth Sleepiness Scale; Nasal Obstruction Symptom Evaluation scale; Berlin Questionnaire. The visual analog scale for snoring was also used.

Results

Of the 44 participants, 18 (41%) were males and 26 (59%) were females. 82% had poor sleep quality. 46% presented excessive daytime sleepiness. There was a high risk for Obstructive Sleep Apnea in 27%. Regarding to nasal symptoms, the mean score in the Nasal Obstructive Symptoms Evaluation was 66.25±25.38. When comparing the groups with good and poor sleep quality, we observed a higher risk for Obstructive Sleep Apnea (p=0.05) in patients with poor sleep quality. Patients at high risk for Obstructive Sleep Apnea had higher scores on the Nasal Obstructive Symptoms Evaluation (p=0.001) and on the analogue snoring scale (p<0.001) compared to patients at low risk.

Conclusions

We observed a high occurrence of poor sleep quality in participants. All participants who were at high risk for obstructive sleep apnea were also classified as having poor sleep quality. An association was also observed between the presence of high risk for obstructive sleep apnea and presence of nasal symptoms.

The effects of nasal decongestion on obstructive sleep apnoea

BACKGROUND

Many studies have indicated associations between impaired nasal breathing and sleep disorders. However, the precise nature of the relationship between nasal patency and sleep remains unclear.

PURPOSE

We analysed the effects of nasal patency on sleep architecture and breath in nasal obstruction-predominant obstructive sleep apnoea (NO-OSA) patients by applying nasal decongestant.

MATERIAL AND METHODS

A randomized, placebo-controlled double-blind crossover study was performed in OSA patients with chronic nasal obstruction and without obvious pharyngeal narrowing. All OSA patients (confirmed by polysomnography) were recruited and completed 2 overnight studies (randomly applying oxymetazoline or placebo). Data collected after oxymetazoline or placebo treatments were compared. The ClinicalTrials.gov identifier is NCT03506178.

RESULTS

Compared with placebo, oxymetazoline resulted in significant increase in rapid eye movement sleep (p = 0.027) and reduction of stage 1 sleep (p = 0.004), as well as arousal index (p = 0.002). Moreover, great improvements in apnoea/hypopnea index (AHI) were observed (p < 0.001); AHI in the supine position was significantly reduced (p = 0.001). Oxygen saturation during sleep was increased significantly [mean oxygen saturation (p = 0.005) and lowest oxygen saturation (p = 0.024)]. Oxygen desaturation index was significantly reduced (p < 0.001).

CONCLUSIONS

Improving nasal patency by decongestant could improve sleep quality, AHI, and oxygen saturation level during sleep.

The influential factors on the morphological changes of upper airway associated with mouth opening

OBJECTIVE

This study aimed to evaluate the influential factors on the morphological changes of upper airway caused by mouth opening (MO).

METHODS

One hundred and thirty-eight obstructive sleep apnea-hypopnea syndrome (OSAHS) patients were enrolled. Anthropometric and demographic data, Friedman tongue position (FTP), and tonsil scores were recorded. Overnight polysomnography and upper airway computed tomography scans under two conditions (mouth closed [MC] and MO) were acquired. Morphological parameters of upper airway were compared between MC and MO. Stepwise multiple linear regression analyses were performed with the variation ratio of upper airway parameters (Para-VRs) from MC to MO as the dependent variable, with age, gender, body mass index, neck circumference, waist circumference, four mandibular indexes, net angle or amount of MO, FTP, and tonsil scores as the independent variables.

RESULTS

Overall analysis and subgroup analyses based on OSAHS severity revealed that the minimal cross-sectional area of oropharyngeal lumen (OXmin) significantly decreased (P < 0.05) with MO, whereas the minimal cross-sectional area of velopharyngeal lumen (VXmin) did not significantly change with MO (P > 0.05). The net angle of MO or amount of MO combined with tonsil scores were identified to have significant positive correlation with EXP (OXmin-VR), [OXmin-VR was logarithmically transformed with an exponential function, EXP(n) = eⁿ ]; FTP appeared to be more related to EXP (VXmin-VR). Mouth opening induced a significant increase VXmin for patient subgroup with FTP grading I and a significant decrease VXmin for patient subgroup with FTP grading IV (P < 0.05).

CONCLUSION

Wider MO combined with larger tonsils lead to narrower oropharyngeal airway. The relative position of tongue to soft palate is the main factor influencing the changes of velopharyngeal lumen with MO.

LEVEL OF EVIDENCE

4 Laryngoscope, 128:2902-2909, 2018.

Guideline Values for Minimum Nasal Cross-Sectional Area in Children

OBJECTIVE

The purpose was to determine age-specific values of the minimum cross-sectional area of the nasal airway in children without cleft lip or palate and to assess whether gender differences occur with growth in order to develop guidelines for assessment in children with clefts.

PARTICIPANTS

All schoolchildren aged 8 to 17 years who met the research criteria were studied during rest breathing using the pressure-flow technique. The children came from a rural area of 3800 inhabitants. Consecutive age cohorts were used for comparisons.

RESULTS

Nasal cross-sectional area increased in females from 0.38 cm² in 8-year-olds to 0.58 cm² in 17-year-olds. There was a decrease in size at ages 10 to 11 and 14 to 15 years. In males, the area increased from 0.40 to 0.68 cm² and decreased slightly from 9 to 10 and 14 to 15 years. The annual changes were statistically significant in females between 8 and 9 and 11 to 13 years of age, and in males from 11 to 12, 13 to 14, and 15 to 17 years of age. Across gender, the only significant difference occurred at age 16.

CONCLUSIONS

Our results indicate that the increase in nasal airway size is not consistent during growth. Nasal airway size showed almost equal values for both genders in young children but was systematically larger in boys from 14 years of age on. The results refer that by 17 years of age nasal airway may not have reached adult size in males.

Palatal implant surgery effectiveness in treatment of obstructive sleep apnea: A numerical method with 3D patient-specific geometries

Obstructive sleep apnea (OSA) affects a large percentage of the population and is increasingly recognized as a major global health problem. One surgical procedure for OSA is to implant polyethylene (PET) material into the soft palate, but its efficacy remains to be discussed. In this study, we provide input to this topic based on numerical simulations. Three 3 dimensional (3D) soft palate finite element models including mouth-close and mouth-open cases were created based on three patient-specific computed tomography (CT) images. A simplified material modeling approach with the Neo-Hookean material model was applied, and nonlinear geometry was accounted for. Young's modulus for the implant material was obtained from uniaxial tests, and the PET implant pillars were inserted to the 3D soft palate model. With the finite element model, we designed different surgical schemes and investigated their efficacy with respect to avoiding the soft palate collapse. Several pillar schemes were tested, including different placement directions, different placement positions, different settings for the radius and the array parameters of the implant pillars, and different Young's moduli for the pillars. Based on our simulation results, the longitudinal-direction implant surgery improved the stiffness of the soft palate to a small degree, and implanting in the transverse direction was evaluated to be a good choice for improving the existing surgical scheme. In addition, the Young's modulus of the polyethylene material implants has an influence on the reinforcement efficacy of the soft palate.

Lip closure training improves eating behaviors and prefrontal cortical hemodynamic activity and decreases daytime sleep in elderly persons

Previous research suggests that aging-related deterioration of oral functions causes not only eating/swallowing disorders but also various conditions such as sleep disorders and higher-order brain dysfunction. The aim of the present study was to examine the effects of lip closure training on eating behavior, sleep, and brain function in elderly persons residing in an elder care facility. The 20 elderly subjects (mean age, 86.3 ± 1.0 years) were assigned to a control group or a lip closure training (LCT) group, in which an oral rehabilitation device was used for daily LCT sessions over a 4-week period. Before and after the 4-week intervention period, maximal lip closure force was measured, and prefrontal cortical hemodynamic activity (changes in oxygenated hemoglobin concentration) during lip closure movements was measured with (LCT group) or without (control group) use of the oral rehabilitation device. We also analyzed eating behavior and daytime sleep before and after the intervention period. Compared with the control group, the LCT group showed improved maximal lip closure force, shortened eating time, decreased food spill rates, and decreased daytime sleeping. Furthermore, compared with the control group, the LCT group showed a significant increase in prefrontal cortical activity during lip closure. In addition, the increase rate in the right dorsolateral prefrontal cortical activity after the intervention period was significantly correlated with the increase rate in the maximal lip closure force after the intervention period. These findings suggest that LCT is useful in elderly individuals with decreased eating/oral and cognitive functions without the risk of pulmonary aspiration during training.

From oral facial dysfunction to dysmorphism and the onset of pediatric OSA

The upper airway is a collapsible tube, and its collapsibility increases during sleep. Extrinsic factors such as atypical craniofacial features may increase the risks of airway collapse. We review early development of oral-facial structures and the anatomical variants that may be present at birth and can impact nasal breathing. After birth, there is a continuous interaction between orofacial functions and growth of anatomic features. We review the dysfunctions identified to date that may impact orofacial development leading to sleep-disordered-breathing through changes in the orofacial growth. The identification of risk-factors, ultimately leading to full-blown obstructive sleep apnea, may allow early recognition of these factors and the development of treatments to eliminate early problems or at least decrease their impact.

The evaluation of pattern and quality of sleep in patients with chronic rhinosinusitis with nasal polyps

OBJECTIVE

The goal of this study is to evaluate the impact of chronic rhinosinusitis with nasal polyps (CRSwNP) on sleep pattern and sleep quality before and after functional endoscopic sinus surgery using subjective and objective parameters.

METHODS

Twenty-two patients with CRSwNP were evaluated. All subjects underwent assessment by nasal endoscopy, rhinomanometry and computed tomography. Sleep pattern and sleep quality were evaluated by Pittsburgh sleep quality index (PSQI) and polysomnography (PSG). All patients were reassessed 6 months after surgery.

RESULTS

Nasal resistance decreased after the surgery (p<0.001). Postoperative PSQI scores were significantly lower than preoperative scores (p<0.001). The preoperative mean values of total apnea index and apnea-hypopnea index were 25.4 and 13.3, respectively. After surgery, the total apnea and apnea-hypopnea index had decreased significantly to 7.8 and 11.2, respectively (p=0.009 and 0.019, respectively).

CONCLUSION

In patients with CRSwNP, functional endoscopic sinus surgery significantly ameliorates sleep pattern and sleep quality. CRSwNP may be a predisposing factor for sleep related respiratory disorders.

Tooth loss and obstructive sleep apnea signs and symptoms in the US population

PURPOSE

The aim of this study is to investigate the relationship between tooth loss and signs and symptoms of obstructive sleep apnea (OSA) in a representative sample of the general US population.

METHODS

Data were from 7305 men and women aged ≥25 years participating in the 2005-2008 National Health and Nutrition Examination Survey. Tooth loss, occlusal contacts, and denture use were determined by dental examination. Four cardinal OSA signs and symptoms were evaluated by questions based on American Academy of Sleep Medicine criteria. Adults with ≥2 signs/symptoms of OSA were classified at high-risk of OSA. Prevalence ratios (PR) and 95 % confidence limits (CL) from log binomial regression models estimated the strength of association between tooth loss and high-risk for OSA, adjusting for demographic characteristics, body mass index, dentures, and sleep duration.

RESULTS

Prevalence of high-risk for OSA increased 2 % for each additional lost tooth (PR = 1.02, 95 % CL, 1.01, 1.03) among adults aged 25 to 65 years. When tooth loss was modeled as an ordinal variable with 0-4 lost teeth as the referent category, adjusted prevalence of high-risk for OSA was as follows: 25 % greater in those missing 5-8 teeth (PR = 1.25, 95 % CL, 1.07, 1.46); 36 % greater in those missing 9-31 teeth (PR = 1.36, 95 % CL, 1.06, 1.73); and 61 % greater in the edentulous (PR = 1.61, 95 % CL, 1.11, 2.33).

CONCLUSION

Tooth loss may be an independent risk factor for OSA.

Three-dimensional computed tomography analysis of airway volume changes between open and closed jaw positions

INTRODUCTION

Airway dimensions are closely linked to the bone and soft-tissue craniofacial anatomy. Reduction of the airway is seen with airway disorders and can impair function. The purpose of this retrospective study was to determine whether changing from open to closed jaw position affects the volume of the nasal cavity, nasopharynx, and oropharynx; the soft palate; the soft-tissue thickness of the airway; and the most constricted area of the airway.

METHODS

Following reliability studies, in this retrospective study, we analyzed cone-beam computed tomography scans taken in both closed and open jaw positions of 60 subjects who were undergoing diagnosis and treatment of temporomandibular disorders. On each scan, condyle-fossa measurements, volumes of airway segments (nasal cavity, nasopharynx, oropharynx), soft palate areas, soft tissue thicknesses of the airway, and the most constricted area of the airway and its location were measured using Dolphin imaging software (version 11.5; Patterson Dental Supply, Chatsworth, Calif). Differences between the 2 jaw positions were analyzed with paired t tests, accepting P ≤0.05 as significant.

RESULTS

Significant changes in airway dimensions were found between the closed and open jaw positions. With jaw opening, the nasopharynx volume increased, whereas the oropharynx volume decreased. Significant decreases were also found for measurements of basion to posterior airway wall, cervical vertebrae to posterior airway wall, most constricted area, nasal cavity volume, and soft palate area when the jaw was open.

CONCLUSIONS

Changing jaw position significantly affects airway dimensions.

New insights on the pathophysiology of inspiratory flow limitation during sleep

INTRODUCTION

Inspiratory flow limitation (IFL) is defined as a "flattened shape" of inspiratory airflow contour detected by nasal cannula pressure during sleep and can indicate increased upper airway resistance especially in mild sleep-related breathing disorders (SRBD). The objective of this study was to investigate the association between upper airway abnormalities and IFL in patients with mild SRBD.

METHODS

This study was derived from a general population study consisting of selected individuals with apnea-hypopnea index (AHI) below 5 events/h of sleep, ("no obstructive sleep apnea" group) and individuals with AHI between 5 and 15 events/h ("mild obstructive sleep apnea" group). A total of 754 individuals were divided into four groups: group 1: AHI <5/h and <30 % of total sleep time (TST) with IFL (515 individuals), group 2: AHI <5/h and >30 % of TST with IFL (46 individuals), group 3: AHI: 5-15/h and <30 % of TST with IFL (168 individuals), and group 4: AHI: 5-15/h and >30 % of TST with IFL (25 individuals).

RESULTS

Individuals with complains of oral breathing demonstrated a risk 2.7-fold larger of being group 4 compared with group 3. Abnormal nasal structure increased the chances of being in group 4 3.2-fold in comparison to group 1. Individuals with voluminous lateral wall demonstrated a risk 4.2-fold larger of being group 4 compared with group 3.

CONCLUSION

More than 30 % of TST with IFL detected in sleep studies was associated with nasal and palatal anatomical abnormalities in mild SRBD patients.

Systematic Evaluation of the Upper Airway in a Sample Population: Factors Associated with Obstructive Sleep Apnea Syndrome

OBJECTIVES

To investigate the anatomy of the upper airway (UA) of a representative sample of the adult population of São Paulo city, Brazil, and to identify factors associated with the presence of obstructive sleep apnea syndrome (OSAS), as confirmed using full-night polysomnography (PSG).

STUDY DESIGN

Cross-sectional study.

SETTING

Population-based sample.

METHODS

A 3-stage sampling procedure was used to proportionally recruit adult residents of São Paulo city according to gender, age, and socioeconomic status. A complete evaluation was performed, including a systematic evaluation of the UA prior to conducting PSG.

RESULTS

Nine-hundred ninety-three (90.2%) of the participants were seen by an ear, nose, and throat (ENT) specialist. Individuals who were diagnosed with OSAS (32.9%) presented a higher frequency of nasal symptoms and structural abnormalities (both nasal and oropharyngeal) compared with those without OSAS. No anatomical differences were observed in the facial skeleton. An abnormal nasal structure visible via anterior rhinoscopy was the only UA factor predicting OSAS after adjustments for the other common OSAS risk factors (male sex, aging, obesity, and increased neck circumference).

CONCLUSION

This is the first study in which a systematic evaluation of the UA was followed by a sleep study in a population-based sample. In a sample of the general population that had not previously been screened for OSAS, having an abnormal nasal structure was found to be a risk factor for OSAS, in conjunction with other well-established clinical and demographic factors, such as male gender, increased age, increased neck circumference, and body mass index.

[Usefulness of the basic exploration of the upper airways and neighbor structures in patients with adult obstructive sleep apnea-hypopnea syndrome]

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a prevalent disease in the general population, associated with an increase in the cardiovascular morbimortality. A basic and/or standardized otolaryngologic exploration could help us to detect the structural abnormalities that alter the upper airway collapsibility and offer a high pre-test risk factor, improve the CPAP adherence or even the possibility of offering alternative treatments. This article offers a revision of the exploration in OSAHS patients. We describe a guideline to identify the main structural abnormalities related to OSAHS. We also include a short algorithm for the diagnosis of OSAHS, when is suspected by primary care physicians.

Nasal obstruction and palate-tongue position on sleep-disordered breathing

OBJECTIVES

We wanted to evaluate whether the presence of nasal obstruction makes a change on the association between the modified Mallampati score and the severity of sleep-disordered breathing (SDB) and the sleep quality.

METHODS

Polysomnography (PSG), the modified Mallampati score (MMS), the body-mass index, and a questionnaire about nasal obstruction were acquired from 275 suspected SDB patients. The subjects were divided into two groups according to the presence of nasal obstruction. The clinical differences between the two groups were evaluated and the associations between the MMS and PSG variables in each group were also assessed.

RESULTS

Significant correlations were found between the MMS and many PSG variables, including the apnea-hypopnea index, the arousal index and the proportion of deep sleep, for the patients with nasal obstruction, although this was not valid for the total patients or the patients without nasal obstruction.

CONCLUSION

The severity of SDB and the quality of sleep are well correlated with the MMS, and especially for the patients with nasal obstruction. The MMS can give more valuable information about the severity of SDB when combined with simple questions about nasal obstruction.

Craniofacial morphologic predictors of oral appliance outcomes in patients with obstructive sleep apnea

BACKGROUND

Oral appliances (OAs) that advance the mandible can improve the intake of oxygen and reduce the number of apneic episodes in patients who have obstructive sleep apnea. Although OAs are not as effective as continuous positive airway pressure therapy, they are an important therapeutic consideration for patients with obstructive sleep apnea. However, the ability to predict efficacy of OAs is limited. The authors conducted a study to assess the value of relevant clinical and cephalometric variables that can help predict the outcome of OA use in an Asian population.

METHODS

Fifty-two Taiwanese patients consecutively treated with OAs were included in the study. Relevant clinical and cephalometric variables were determined at baseline. Treatment success was defined as a reduction of more than 50 percent in the apnea-hypopnea index and the residual apnea-hypopnea index less than 10 per hour with OAs. The predictive value of variables for treatment outcome was evaluated by means of univariate and multivariate analyses. A receiver operating characteristic curve for the multivariate logistic regression model was constructed.

RESULTS

A good outcome was found in 29 participants (56 percent). Minimal retroglossal airway, mandibular position and anterior face height were significant predictors of OA treatment success. The area under the receiver operating characteristic curve was 0.862, reflecting good model discrimination.

CONCLUSIONS

Some cephalometric variables had a predictive value for the outcome of OA use. OA treatment outcome was favorable in patients with certain craniofacial structures such as narrow minimal retroglossal airway, mandibular retrusion and short anterior face height.

CLINICAL IMPLICATIONS

Practitioners should consider OAs for treatment of patients with obstructive sleep apnea who have narrow minimal retroglossal airways, mandibular retrusion and short anterior face heights.

Change of obstruction level during drug-induced sleep endoscopy according to sedation depth in obstructive sleep apnea

OBJECTIVES/HYPOTHESIS

We evaluated the change in upper airway collapse according to the depth of sedation during drug-induced sleep endoscopy (DISE), as well as characteristics possibly associated with that change.

STUDY DESIGN

Prospective, single center, observational study.

METHODS

Twenty-nine patients with upper airway collapse were twice evaluated using DISE according to the depth of sedation, as confirmed by the bispectral index (BIS), which is a measure of the level of consciousness. Changes in the site and degree of obstruction according to the change in sedation depth at the retropalatal and the retroglossal levels were evaluated. The possible contributing factors of this change were explored.

RESULTS

As DISE sedation deepened, the upper airway became narrower in 37% of patients at the retropalatal level and in 44.8% of patients at the retroglossal level. No clinical, polysomnographic, or cephalometric variables showed any association with the change in the degree of retroglossal airway narrowing, with the exception of mouth breathing during DISE.

CONCLUSIONS

The degree of upper airway narrowing can be aggravated according to the sedation depth. The monitoring of sedation depth during DISE is critical, especially in patients with mouth breathing.

Polysomnographic effect of nasal surgery on positional and non-positional obstructive sleep apnea/hypopnea patients

CONCLUSION

The polysomnographic (PSG) effects of nasal surgery on positional obstructive sleep apnea/hypopnea syndrome (OSAHS) patients (PPs) and non-positional OSAHS patients (NPPs) were different.

OBJECTIVE

We aimed to determine the PSG data changes after nasal surgery and evaluate the PSG effect of nasal surgery on PPs and NPPs, respectively.

METHODS

A total of 79 OSAHS patients with nasal obstruction were recruited. Preoperative rhinomanometry and overnight polysomnography were recorded. Patients were distributed into three groups based on the severity level of the apnea and hypopnea indexes (AHI) (mild, moderate, and severe OSAHS). Three groups were each subdivided into two subgroups (PPs and NPPs). Postoperative data were obtained at least 6 months later.

RESULTS

After surgery, although nasal resistance decreased significantly in all patients, the total rate of success and response in treating OSAHS was only 22.7%. Grouped on the basis of the severity level of AHI, the lowest SpO2 increased and AHI, supine AHI, and arousal indexes decreased significantly only in mild OSAHS (p < 0.05). Subdivided according to the presence or absence of positional dependency, the lowest SpO2 increased and supine AHI decreased significantly in both PPs and NPPs with mild OSAHS and in PPs with moderate OSAHS (p < 0.05). AHI significantly increased in PPs with severe OSAHS (p < 0.05). Supine sleep time was relatively prolonged significantly in PPs with moderate and severe OSAHS (p < 0.05).

Changes in the upper and lower pharyngeal airway spaces associated with rapid maxillary expansion

Objectives. The primary objectives of this retrospective study were first to compare the upper and lower pharyngeal airway spaces between orthodontic patients with and without maxillary constriction and second to evaluate the effect of rapid maxillary expansion (RME) on these airway spaces. A secondary objective was to compare the mode of breathing between groups. Materials and Methods. The experimental (RME) group consisted of 30 patients (mean age, 14.2 ± 1.3 years, 16 boys and 14 girls) with maxillary constriction who were treated with hyrax-type RME. The control group comprised the records of age- and gender matched patients (mean age, 13.8 ± 1.5 years, 16 boys and 14 girls) with no maxillary constriction but requiring nonextraction comprehensive orthodontic treatment. Cephalometric measurements in the sagittal dimension of upper and lower airway spaces for the initial and final records were recorded. Mode of breathing and length of treatment were also compared. Results. The sagittal dimension of the upper airway increased significantly in the RME group (mean = 1.3 mm) compared to the control group (mean = 0.5 mm), P = 0.016. However, there was no significant difference in the lower pharyngeal airway measurement between the RME group (mean = 0.2) and the control group (mean = 0.4), P = 0.30. There was no significant difference with respect to mode of breathing between the two groups (P = 0.79). Conclusion. Rapid maxillary expansion (RME) during orthodontic treatment may have a positive effect on the upper pharyngeal airway, with no significant change on the lower pharyngeal airway.

Craniofacial morphology and sleep apnea in children with obstructed upper airways: differences between genders

OBJECTIVES

To correlate sleep apnea with craniofacial characteristics and facial patterns according to gender.

METHODS

In this prospective survey we studied 77 male and female children (3-12 years old) with an upper airway obstruction due to tonsil and adenoid enlargement. Children with lung problems, neurological disorders and syndromes, obstructive septal deviation, previous orthodontic treatment, orthodontic surgeries or oral surgeries, or obesity were excluded. Patients were subjected to physical examinations, nasal fiberoptic endoscopy, teleradiography for cephalometric analysis, and polysomnography. Cephalometric analysis included the following skeletal craniofacial measurements: facial axis (FA), facial depth (FD), mandibular plane angle (MP), lower facial height (LFH), mandibular arch (MA), and vertical growth coefficient (VERT) index.

RESULTS

The prevalence of sleep apnea was 46.75% with no statistical difference between genders. Among children with obstructive sleep apnea (Apneia Hypopnea Index - AHI ≥ 1) boys had higher AHI values than girls. A predominance of the dolichofacial pattern (81.9%) was observed. The following skeletal craniofacial measurements correlated with AHI in boys: FD (r(s)=-0.336/p=0.020), MP (r(s)=0.486/p=0.00), and VERT index (r(s)=-0.337/p=0.019). No correlations between craniofacial measurements and AHI were identified in girls.

CONCLUSIONS

Craniofacial morphology may influence the severity of sleep apnea in boys but not in girls.

Systematic evaluation of the upper airway in the adult population of São Paulo, Brazil

OBJECTIVES

To study the prevalence of otorhinolaryngologic symptoms and findings of physical examination of the upper airway (UA) of a representative sample of the adult population of São Paulo, Brazil, and the association between these findings.

STUDY DESIGN

Cross-sectional survey.

SETTING

Population sample.

METHODS

A total of 1101 randomly selected volunteers representing the adult population of São Paulo according to sex, age, and socioeconomic class were included in this study. Otorhinolaryngological evaluation included investigation of nasal complaints, physical examination of the UA, and a facial inspection.

RESULTS

A total of 993 volunteers (53.9% women), with a mean age of 41.8 ± 0.89 years, underwent otorhinolaryngologic examination. The most prevalent symptoms were the following: symptoms suggestive of rhinitis (44.9%), snoring (42.8%), mouth breathing (39.3%), and nasal obstruction (33.3%). In physical examination, the most common findings were a web palate (redundant posterior pillar; 62.9%), septum deviation (56.9%), and inferior turbinate hypertrophy (37.7%). Significant associations were found between nasal obstruction and septum deviations, inferior turbinate hypertrophy, high-arched palate, and class II dental occlusion; between symptoms of rhinitis and inferior turbinate hypertrophy; and between snoring and obstructive deviated septum, modified Mallampatti grades III and IV, increased neck circumference, and age greater than or equal to 50 years.

CONCLUSIONS

The prevalence of otorhinolaryngologic symptoms and alterations in physical examination of the UA were high in the adult population of São Paulo, Brazil. The snoring and nasal symptoms were significantly associated with findings from UA physical examination and inspection of the facial skeleton.

Surgical options for the treatment of obstructive sleep apnea

Obstructive sleep apnea (OSA) is a prevalent condition characterized by repetitive airway obstruction during sleep with associated increased morbidity and mortality. Although CPAP is the preferred treatment, poor compliance is common. Patients intolerant of conventional OSA medical treatment may benefit from surgical therapy to alleviate pharyngeal obstruction. Case series suggest that maxillomandibular advancement has the highest surgical efficacy (86%) and cure rate (43%). Soft palate surgical techniques are less successful, with uvulopalatopharyngoplasty having an OSA surgical success rate of 50% and cure rate of 16%. Further research is needed to more thoroughly assess clinical outcomes (eg, quality of life, morbidity), better identify key preoperative patient and clinical characteristics that predict success, and confirm long-term effectiveness of surgical modalities to treat OSA.

The role of the nose in the pathogenesis of obstructive sleep apnea

PURPOSE OF REVIEW

To define the relationship between obstructive sleep apnea (OSA) and nasal obstruction, we have reviewed the literature on epidemiological, physiological, and randomized controlled studies in which the relationship between nasal obstruction and OSA was investigated.

RECENT FINDINGS

Data from observational studies suggest that nasal obstruction contributes to the pathogenesis of OSA. Recently, studies have mainly focused on the effects of therapeutic interventions on the nose and OSA. Eleven trials with randomized controlled designs were found; external nasal dilators were used in five studies, topically applied steroids in one, nasal decongestants in three, and surgical treatment in two studies. Data from these studies showed only minor improvement in the symptoms and severity of OSA.

SUMMARY

The current evidence suggests that the nose may not play a significant role in the pathogenesis of OSA. The impact of treating nasal obstruction in patients with OSA on long-term outcome remains to be defined more accurately through randomized controlled trials of medical and surgical therapies with large numbers of patients.