Anterior nasal resistance in obese children with obstructive sleep apnea syndrome

Drug-Induced sleep endoscopy in children: NAVOTEL scoring system development

OBJECTIVES

Pediatric drug-induced sleep endoscopy (DISE) lacks a universal and easy-to-use scoring system. The velum, oropharynx, tongue, epiglottis (VOTE) scoring system is widely used but needs to be completed in pediatrics. The main objective of this study was to investigate the distribution of obstructive sites in DISE and to propose an appropriate pediatric scoring system. The secondary objective was to evaluate the changes in surgical management induced by the proposed scoring system.

METHODS

A single-center prospective 5-year study was conducted from March 2016 to December 2021, including 99 children with a mean age of 7.2 years (±3.7), with pathological preoperative sleep recordings and undergoing DISE. The distribution of all upper airway obstructive sites was studied.

RESULTS

Adenoids (A) were the most frequent obstructive site (63% of patients), and the nasal cavities (N) and the larynx (L) were other frequent obstructive sites. These sites are not explored by the VOTE scoring system, leading to the creation of the nose, adenoids, velum, oropharynx, tongue, epiglottis, larynx (NAVOTEL) scoring system. NAVOTEL was significantly correlated with the severity of obstructive sleep apnea-hypopnea syndrome (OSAS) (ρ = 0.2; p = 0.04) and highlighted obstructive sites in 6/9 patients with VOTE = 0. Of these patients, 4 had a complete obstructive site, and 3 had a multisite obstruction. VOTE indicated 8 additional surgical actions; NAVOTEL indicated 50 other actions compared to clinical examination. The NAVOTEL scoring system was exhaustive regarding surgical indications for OSAS.

CONCLUSIONS

The NAVOTEL scoring system is exhaustive in pediatric DISE and correlated to OSAS severity. It should be preferred in pediatric DISE.

Correlating Nasal Patency with Obstructive Sleep Apnea in Obese Versus Non-Obese Patients: An Acoustic Rhinometry Study

The aim of this study was to correlate nasal patency with Obstructive Sleep Apnea (OSA) in obese versus non-obese patients using Acoustic Rhinometry (AR). Eccovision® Acoustic Rhinometer equipment was used to compare nasal cross-sectional areas (CSA1,2 & 3 corresponding to nasal valve region, anterior portion of middle & inferior turbinate and posterior portion of middle & inferior turbinate respectively) and volume in age and gender matched sample divided into three groups: Group 1: Non-obese patients without OSA (25 patients, 13 males and 12 females); Group 2: Non-obese patients with OSA (25 patients, 14 males and 11 females); Group 3: Obese patients with OSA (25 patients, 13 males and 12 females). The mean nasal cross-sectional areas and volume were lower in Group 2 compared to Group 1 but statistically non-significant (P value > 0.05 for all). The mean nasal cross-sectional areas and volume were significantly lower in Group 3 as compared to Groups 1 and 2 (P value < 0.05 for all). BMI showed a statistically significant positive (direct) correlation with AHI in Groups 2 and 3 (P value < 0.05 for both). The nasal cross-sectional areas and volume showed a statistically significant negative (inverse) correlation with AHI in Groups 2 and 3 (P value < 0.05 for both). OSA diagnosed cases with high BMI may not present with an obvious nasal obstruction; the nasal patency may still be compromised due to reduced nasal lumen secondary to obesity. AR, being cost-effective and non-invasive modality; is advocated to evaluate pre-treatment nasal patency, as well as follow up evaluation to ascertain improvement after the intervention.

Specific dento-craniofacial characteristics in non-syndromic children can predispose to sleep-disordered breathing

AIM

To ascertain and illustrate specific clinical dento-craniofacial characteristics associated with sleep-disordered breathing (SDB) in non-syndromic children.

METHODS

Narrative review of literature on SDB, dental occlusion and craniofacial morphology retrieved through online literature database search for these terms. The review focused on clinical examples and graphical illustrations in order to ascertain the association between dento-craniofacial characteristics and SDB. Only publications concerning healthy non-syndromic children without any somatic or psychological diagnosis were included.

RESULTS

Dento-craniofacial characteristics such as anterior open bite, large overjet, cross bite and facial appearance such as convex profile due to mandibular retrognathia and inclination, narrow and high palate can predispose to SDB in non-syndromic children. Furthermore, extended head posture, mouth breathing and general adenoidal face may be symptoms or predisposing factors to SDB in non-syndromic children.

CONCLUSION

Dento-craniofacial characteristics as anterior open bite, large overjet due to mandibular retrognathia, cross bite, and narrow and high palate can predispose to SDB in non-syndromic children. Facial characteristics predisposing to SDB can be a convex facial profile, extended head posture, mouth breathing and general adenoidal face. Interdisciplinary collaboration between medical doctors and dentists can prove valuable in diagnostics, prevention and treatment of SDB in non-syndromic children.

Clinical parameters influencing the results of anterior rhinomanometry in children

BACKGROUND

Nasal obstruction is a frequent symptom in both adults and children and it is a common reason to see an otorhinolaryngologist. Endoscopy of the nasal cavity and the epipharyngeal space along with anterior rhinomanometry is regarded the gold standard since many years to estimate the severity of nasal obstruction in the particular patient. Endoscopy shows anatomical reasons for an obstruction, whereas the nasal flow volume and nasal resistance can be determined using anterior rhinomanometry. Currently, there are only few data available for rhinomanometry results in children. The purpose of the present study was to evaluate the application of this technique in the pediatric population for objective evaluation of nasal flow. Whether it achieves reproducible results and which clinical parameters have some influence on the results were studied.

PATIENTS AND METHODS

427 children (average age of 8.5 years, range 7 months through 17 years) who were admitted to evaluate nasal patency or for allergy testing were examined. After clinical examination and endoscopy of the nasal cavity and epipharyngeal space, anterior rhinomanometry was performed before and after application of decongestant nose drops separately for each nose side in 334 children. The nasal flow with a pressure of 150 Pasc was measured and served for statistical evaluation. Flow values were correlated to clinical and endoscopic parameters along with results of allergy tests (prick tests).

RESULTS

Reproducible rhinomanometric measurements were possible in children age 3 years and older. However, the standard deviation and variation of measurements were significant in this cohort of patients. Statistically highest significant correlations were found between flow measurements and body height along with the age of the children (p < 0.01) and status following adenoidectomy (p < 0.05). No statistically significant correlations were found between rhinomanometry and results of prick tests.

CONCLUSIONS

The study demonstrates that rhinomanometry can be applied in the pediatric population for objective evaluation of nasal obstruction and for determining the effects of decongestant nose drops. The highest correlation was found between nasal flow and children's body height, children's age and status following adenoidectomy. The correlation between nasal flow and clinically/endoscopically determined degree of nasal obstruction was lower. However, definition of normal flow values for particular age groups is challenging since the results showed high variation and standard deviation. Yet with regard to individual patient, the technique achieves reliable results in nasal provocation tests, which are widely used for allergy testing in children. When performed in children it should always be considered that there are age-specific requirements for the examination and interpretation of results in this patient cohort.

Upper airway effective compliance during wakefulness and sleep in obese adolescents studied via two-dimensional dynamic MRI and semiautomated image segmentation

Novel biomarkers of upper airway biomechanics may improve diagnosis of obstructive sleep apnea syndrome (OSAS). Upper airway effective compliance (EC), the slope of cross-sectional area versus pressure estimated using computational fluid dynamics (CFD), correlates with apnea-hypopnea index (AHI) and critical closing pressure (P_crit). The study objectives are to develop a fast, simplified method for estimating EC using dynamic MRI and physiological measurements and to explore the hypothesis that OSAS severity correlates with mechanical compliance during wakefulness and sleep. Five obese children with OSAS and five control subjects with obesity aged 12-17 yr underwent anterior rhinomanometry, polysomnography, and dynamic MRI with synchronized airflow measurement during wakefulness and sleep. Airway cross section in retropalatal and retroglossal section images was segmented using a novel semiautomated method that uses optimized singular value decomposition (SVD) image filtering and k-means clustering combined with morphological operations. Pressure was estimated using rhinomanometry Rohrer's coefficients and flow rate, and EC was calculated from the area-pressure slope during five normal breaths. Correlations between apnea-hypopnea index (AHI), EC, and cross-sectional area (CSA) change were calculated using Spearman's rank correlation. The semiautomated method efficiently segmented the airway with average Dice Coefficient above 89% compared with expert manual segmentation. AHI correlated positively with EC at the retroglossal site during sleep (r_s = 0.74, P = 0.014) and with change of EC from wake to sleep at the retroglossal site (r_s = 0.77, P = 0.01). CSA change alone did not correlate significantly with AHI. EC, a mechanical biomarker which includes both CSA change and pressure variation, is a potential diagnostic biomarker for studying and managing OSAS.NEW & NOTEWORTHY This study investigated the dynamics of the upper airway at retropalatal and retroglossal sites during wakefulness and sleep by evaluating the effective compliance (EC) of each site and its correlation with apnea-hypopnea index (AHI) using novel semiautomated image processing. AHI correlated significantly with retroglossal EC during sleep and change of retroglossal EC from wake to sleep. The results suggest EC as a promising noninvasive diagnostic marker for estimating the mechanical properties of various upper airway regions in patients with OSAS.

Nasal Obstruction as a Potential Factor Contributing to Hypoxemia in Obstructive Sleep Apnea

PURPOSE

This study aimed to evaluate the correlation between nasal resistance and oxygen desaturation to better elucidate the role of nasal obstruction in the pathophysiology of obstructive sleep apnea (OSA).

PATIENTS AND METHODS

Eighty-eight OSA patients aged between 22 and 77 years were enrolled in this study. Nasal resistance was measured at pressures of 75, 150, and 300 Pa, with the patients first in the seated position than in the supine position. Relationships between the oximetric variables and nasal resistance in the seated and supine positions were analyzed.

RESULTS

From seated to supine position, a statistically significant increase in nasal resistance was observed at pressures of 75 and 150 Pa (p=0.001 and p=0.006, respectively). Significant positive correlations were noted between nasal resistance in the supine position at 75 Pa (SupineNR75) and oximetry variables, including oxygen desaturation index (ODI, p=0.015) and the percentage of total time with oxygen saturation level lower than 90% (T < 90%, p=0.012). However, significant positive correlations existed only in moderate to severe OSA when the study group was further divided into two subgroups (mild vs moderate to severe OSA). Body mass index (β = 0.476, p<0.001) and SupineNR75 (β = 0.303, p=0.004) were identified as independent predictors for increased ODI.

CONCLUSION

Nasal resistance in the supine position measured at 75 Pa significantly correlated with the severity of oxygen desaturation. Therefore, nasal obstruction may play an important role in the pathophysiology of hypoxemia in OSA patients, especially in patients with moderate to severe OSA.

Comparison of nasal geometry among adults with obstructive sleep apnea: a preliminary study

ABSTRACT Purpose: to compare nasal geometry between two groups of patients with different degrees of obstructive sleep apnea and to correlate apnea-hypopnea index, apnea severity and degree of daytime sleepiness with nasal areas and volume. Methods: a total of 20 adults (15 women and 5 men, mean age of 52.0±11.4 years old) without nasal obstruction were submitted to polysomnography. The subjects were divided into two groups: a) 10 individuals without apnea or with mild-grade apnea; b) 10 with moderate or severe apnea. Nasal geometry was evaluated by acoustic rhinometry. The volume, comprising the distance from the nasal valve to the posterior part of the middle nasal turbinate, and the three sectional areas corresponding to nasal valve, anterior part of the inferior nasal turbinate and posterior part of the inferior nasal turbinate, were considered. The Shapiro-Wilk, Mann-Whitney, Student’s t tests for independent samples and Spearman’s correlation coefficient were used for the analysis, with a significance level lower than 5%. Results: group 2 presented lower values in the area corresponding to the nasal valve (on the right), and higher values in the nasal turbinate areas. There was no correlation between the drowsiness scale and nasal areas and volumes. Conclusion: the area of the nasal valve was unilaterally smaller in the group with moderate and severe apnea. There was no correlation between volumes and nasal areas and excessive daytime sleepiness.

Association of allergic rhinitis with obstructive sleep apnea: A meta-analysis

BACKGROUND

The co-existence of allergic rhinitis (AR) and obstructive sleep apnea (OSA) is a common phenomenon in clinical practice. AR has long been considered a risk factor for OSA. However, the relationship is not completely clear. Therefore, we conducted a meta-analysis to evaluate the prevalence of AR in sleep-disordered breathing (SDB) /OSA and their relationship.

METHODS

A comprehensive literature search was performed in PubMed/Medline, Google Scholar, Wiley Online Library, EMBASE, and Web of Science. Data were analyzed and pooled to estimate effect size (ES) /odds ratio (OR) with 95% confidence intervals (95%CI). Heterogeneity was quantified and evaluated by chi-squared-based Q-test and I2 test, with P < .05 and I > 50% indicating evidence of heterogeneity.

RESULTS

44 studies contained 6086 participants were included in this meta-analysis. For adults, the prevalence of AR was 22.8 (95% CI, 15.0-30.6) % in SDB and 35.2 (95% CI, 25.6-44.7) % in OSA. In children with SDB and OSA, the prevalence of AR was 40.8 (95% CI, 24.3-57.2) %, and 45.2 (95% CI, 25.4-65.0) % respectively. The odds ratios of prevalence of the SDB pediatric patients with AR was 2.12 (95%CI, 1.75, 2.57; P < .0001) times higher than that of non-SDB pediatric patients. There were no significant differences between OSA adults with or without AR in BMI (Body Mass Index), neck circumference, apnea hypopnea index (AHI) and epworth sleep scale score (ESS).

CONCLUSION

The prevalence of AR in OSA/SDB is considerably high and children with SDB suffering from a higher incidence of AR than non-SDB. OSA adults accompanied with AR do not have any influences on sleep parameters.

Risk factors associated with obstructive sleep apnea-hypopnea syndrome in Chinese children: A single center retrospective case-control study

Pediatric obstructive sleep apnea-hypopnea syndrome is caused by multiple factors. The present study aimed to investigate the potential risks of pediatric obstructive sleep apnea hypopnea syndrome (OSAHS) and their correlation with the disease severity. A total of 338 pediatric patients with OSAHS (polysomnography (PSG) diagnosis) were enrolled between June 2008 and October 2010. These pediatric patients were divided into mild, moderate and severe subgroups according to the obstructive apnea index (OAI) and/or apnea hypoventilation index (AHI). A total of 338 pediatric patients with vocal nodules who were without obstruction of the upper respiratory tract were enrolled as the control group. The patients were analyzed retrospectively. The average number of upper respiratory tract infections each year and tonsil hypertrophy, adenoid hypertrophy, positive serum tIgE, chronic sinusitis, nasal stenosis, craniofacial features and obesity were significantly higher in OSAHS compared with controls (P<0.01). The parameters the average number of upper respiratory tract infections each year (OR: 1.395, 95% CI: 1.256–1.550), adenoid hypertrophy (OR: 8.632, 95% CI: 3.990–18.672), tonsil hypertrophy (OR: 9.138, 95% CI: 4.621–18.073), nasal stenosis (8.023, 95% CI: 3.633–17.717) and chronic sinusitis (OR: 27.186, 95% CI: 13.310–55.527) were independent factors of pediatric OSAHS (P<0.01). The distribution of chronic sinusitis, nasal stenosis, craniofacial features and obesity indicated a gradual increasing trend in the severity of OSAHS (P<0.01). Number of upper respiratory tract infections per year, adenoid hypertrophy, tonsil hypertrophy, chronic sinusitis, nasal stenosis, infections, allergic reactions, craniofacial features and obesity may be potential risk factors of pediatric OSAHS.

Computational fluid dynamics upper airway effective compliance, critical closing pressure, and obstructive sleep apnea severity in obese adolescent girls

Obstructive sleep apnea syndrome (OSAS) is associated with anatomical abnormalities restricting upper airway size and functional factors decreasing pharyngeal dilator activity in sleep. In this study we hypothesized that OSAS is also associated with altered pharyngeal mechanical compliance during wakefulness. Five OSAS and six control obese girls between 14 and 18 years of age were studied. All underwent polysomnography, critical closing pressure (P_crit) studies, and dynamic MRI of the upper airway during awake tidal breathing. Effective airway compliance was defined as the slope of cross-sectional area vs. average pressure between maximum inspiration and maximum expiration along the pharyngeal airway. Pharyngeal pressure fields were calculated by using image-based computational fluid dynamics and nasal resistance. Spearman correlations were calculated to test associations between apnea-hypopnea index (AHI), P_crit, and airway compliance. Effective compliances in the nasopharynx (C_NP) and velopharynx (C_VP) were lower and negative in OSAS compared with controls: -4.4 vs. 1.9 (mm²/cmH₂O, P = 0.012) and -2.1 vs. 3.9 (mm²/cmH₂O, P = 0.021), respectively, suggesting a strong phasic pharyngeal dilator activity during inspiration in OSAS compared with controls. For all subjects, C_NP and AHI correlated negatively (r_S = -0.69, P = 0.02), and passive P_crit correlated with C_NP (r_S = -0.76, P = 0.006) and with AHI (r_S = 0.86, P = 0.0006). Pharyngeal mechanics obtained during wakefulness could be used to characterize subjects with OSAS. Moreover, negative effective compliance during wakefulness and its correlation to AHI and P_crit suggest that phasic dilator activity of the upper pharynx compensates for negative pressure loads in these subjects.

Airway Resistance in Children with Obstructive Sleep Apnea Syndrome

STUDY OBJECTIVES

Enlarged tonsils and adenoids, the main cause of obstructive sleep apnea syndrome (OSAS) in children, results in upper airway (UA) loading. This contributes to the imbalance between structural and neuromotor factors ultimately leading to UA collapse during sleep. However, it is unknown whether this UA loading can cause elevated airway resistance (AR) during wakefulness. We hypothesized that children with OSAS have elevated AR compared to controls and that this improves after OSAS treatment.

METHODS

Case control study performed at an academic hospital. Children with OSAS and nonsnoring healthy controls underwent baseline polysomnography and spirometry, and AR measurement by body plethysmography while breathing via an orofacial mask. Children with OSAS repeated the previously mentioned tests after adenotonsillectomy.

RESULTS

31 OSAS participants (mean age ± SD = 9.7 ± 3.0 y, obstructive apnea-hypopnea index (OAHI) median [range] = 14.9 [2-58.7] events/h, body mass index [BMI] z = 1.5 ± 1) and 31 controls (age = 10.5 ± 2.5 y, P = 0.24; OAHI = 0.4 [0-1.4], P < 0.001; BMI z = 0.9 ± 1, P = 0.01) were tested. OSAS AR at baseline was 3.9 [1.5-10.3] cmH2O/L/sec and controls 2.8 [1.4 - 6.2] (P = 0.027). Both groups had similar spirometry results. 20 patients with OSAS were tested 6.4 ± 6.6 mo after adenotonsillectomy. OAHI decreased from 15.2 [2.1-58.7] to 0.5 [0 - 5.1] events/h postoperatively (P < 0.001), and AR decreased from 4.3 [1.5 - 10.3] to 2.8 [1.7 - 4.7] cmH2O/L/sec (P = 0.009).

CONCLUSIONS

Children with OSAS have elevated AR that decreases after treatment. This is likely because of upper airway loading secondary to adenotonsillar hypertrophy and may contribute to the increased frequency of respiratory diseases in untreated children with OSAS.

Assessment of pediatric obstructive sleep apnea using a drug-induced sleep endoscopy rating scale

OBJECTIVES/HYPOTHESIS

Assess the reliability of a Sleep Endoscopy Rating Scale (SERS) and its relationship with pediatric obstructive sleep apnea (OSA) severity.

STUDY DESIGN

Retrospective case series of pediatric patients who underwent drug-induced sleep endoscopy (DISE) at the time of surgery for OSA from January 1, 2013 to May 1, 2014.

METHODS

Three blinded otolaryngologists scored obstruction on DISE recordings as absent (0), partial (+1), or complete (+2) at six anatomic levels: nasal airway, nasopharynx, velopharynx, oropharynx, hypopharynx, and arytenoids. Ratings were summed for a SERS total score (range, 0-12). Reliability was calculated using a κ statistic with linear weighting. SERS ratings and obstructive apnea-hypopnea index (OAHI) were compared using Spearman correlation. A receiver operating characteristic (ROC) analysis determined the ability of the SERS total score to predict severe OSA (OAHI >10).

RESULTS

Thirty-nine patients were included (mean age, 8.3 ± 5.1 years; 36% obese; mean OAHI, 19.1 ± 23.7). Intrarater and inter-rater reliability was substantial-to-excellent (κ = 0.61-0.83) and fair-to-substantial (κ = 0.33-0.76), respectively. Ratings correlated best with OAHI for the oropharynx (r = 0.54, P = .02), hypopharynx (r = 0.48, P = .04), and SERS total score (r = 0.75, P = .002). In ROC analysis, a SERS total score ≥6 demonstrated sensitivity/specificity of 81.8%/87.5%, respectively, and correctly classified 84% of patients.

CONCLUSIONS

The SERS can be applied reliably in children undergoing DISE for OSA. Ratings of the oropharynx, hypopharynx, and SERS total score demonstrated significant correlation with OSA severity. A SERS total score ≥6 was an accurate predictor of severe OSA.

LEVEL OF EVIDENCE

4. Laryngoscope, 126:1492-1498, 2016.

Cephalometric pattern and nasal patency in children with primary snoring: the evidence of a direct correlation

Introduction

Sleep disordered breathing (SDB) might affect craniofacial growth and children with obstructive sleep apnea syndrome present an increase in total and lower anterior heights of the face and a more anterior and inferior position of the hyoid bone when compared to nasal breathers.

Objective

To investigate the correlation between rhinomanometric and cephalometric parameters in children with primary snoring (PS), without apnea or gas exchange abnormalities.

Materials and Methods

Thirty children with habitual snoring (16 females and 14 males) aged 4–8 years (mean age 6.85±1.51 years) were selected by a SDB validate questionnaire. All subjects underwent lateral cephalometric, panoramic radiographies.

Results

In our sample 10 children (33%) had snoring 3 nights/week, 11 (37%) 4–6 nights/week and 9 (30%) every night/week. Overall 7 patients (23.3%) were affected by adenoid hypertrophy (AH), 4 (13.3%) by tonsillar hypertrophy (TH) and 13 (43.3%) by AH and TH. We found a more vertical position of the hyoid bone to the mandibular plane (H⊥VT) in patients with a higher frequency (7.3±2.7 vs 7.6±3.7 vs 10.9±2.5 in children snoring 3 nights/week, 4–6 nights/week and every night/week respectively; p = 0.032). Concerning nasal patency significant correlations were found with ANB (maxillary and jaw position with respect to the cranial base), NS∧Ar (growth predictor), sumangle, FMA (total divergence), SnaSnp∧GoMe (inferior divergence), BaN∧PtGn (facial growth pattern), Phw1_PsP (posterosuperior airway space), AHC3H (the horizontal distance between the most anterosuperior point of the hyoid bone and the third cervical vertebra).

Conclusion

The present study supports the relationship between nasal obstruction and specific craniofacial characteristics in children with primary snoring and lead us to hypothesize that nasal obstruction might explain the indirect link between snoring and cephalometric alterations.