Cine Magnetic Resonance Imaging: Evaluation of Persistent Airway Obstruction after Tonsil and Adenoidectomy in Children with Down Syndrome

Advanced Diagnostic Techniques in Obstructive Sleep Apnea

Optimal surgical and medical management of obstructive sleep apnea requires clinically reliable identification of patterns and sites of upper airway obstruction. A wide variety of modalities have been used to evaluate upper airway obstruction. Drug-induced sleep endoscopy (DISE) and cine MRI are increasingly used to identify upper airway obstruction sites, to characterize airway obstruction patterns, to determine optimum medical and surgical treatment, and to plan individualized surgical management. Here, we provide an overview of the applications of DISE and cine MRI in assessing upper airway obstruction in children and adults with obstructive sleep apnea.

Polysomnographic outcomes of revision adenoidectomy in children with obstructive sleep apnea and recurrent/residual adenoidal hypertrophy

INTRODUCTION

Recurrent/residual adenoidal hypertrophy after adenotonsillectomy in children can result in obstructive sleep apnea (OSA). We aimed to assess the polysomnographic (PSG) outcomes of revision adenoidectomy in children with recurrent/residual adenoidal hypertrophy and OSA.

METHODS

This was a single-center retrospective study that included children with sleep studies that confirmed OSA and known history of adenotonsillectomy who were diagnosed with adenoidal hypertrophy and subsequently underwent revision adenoidectomy. Pre- and postoperative PSG variables of revision adenoidectomy were included in the analysis.

RESULTS

A total of 20 children were included in the study. The cohort included 13 males and 7 females with a mean age of 7.8 years (± 3.6 years). The mean BMI z score was 1.96 [1.31, 2.43]. The median duration from adenotonsillectomy performance was 2.3 years [1.4, 4.0]. Overall, revision adenoidectomy resulted in significant improvements in multiple respiratory parameters, including AHI 6.6 [1.4, 13. 7] vs 14.8 [7.4, 20.7], p = 0.02; oxygen desaturations nadir 88.0 [84.0, 93.0] vs 80.0 [72.2, 88.9], p = 0.01; supine AHI 8.6 [1.5, 14.3] vs 17.6 [8.3, 30.2], p = 0.02; and arousal index 12.2 [9.6, 15.7] vs 18.9 [13.4, 24.9], p = 0.04.

CONCLUSIONS

Children with recurrent/residual adenoidal hypertrophy after adenotonsillectomy who undergo revision adenoidectomy experience improvements in respiratory event, gas exchange, and arousal index.

Advanced Diagnostic Techniques in Obstructive Sleep Apnea

Optimal surgical and medical management of obstructive sleep apnea (OSA) requires clinically reliable identification of patterns and sites of upper airway obstruction. A wide variety of modalities has been used to evaluate upper airway obstruction. Drug-induced sleep endoscopy (DISE) and cine MRI are increasingly used to identify upper airway obstruction sites, to characterize airway obstruction patterns, to determine optimum medical and surgical treatment, and to plan individualized surgical management. Here, the authors provide an overview of the applications of DISE and cine MRI in assessing upper airway obstruction in children and adults with OSA.

Diagnosis of Paediatric Obstructive Sleep-Disordered Breathing beyond Polysomnography

Obstructive sleep-disordered breathing (SDB) has significant impacts on health, and therefore, a timely and accurate diagnosis is crucial for effective management and intervention. This narrative review provides an overview of the current approaches utilised in the diagnosis of SDB in children. Diagnostic methods for SDB in children involve a combination of clinical assessment, medical history evaluation, questionnaires, and objective measurements. Polysomnography (PSG) is the diagnostic gold standard. It records activity of brain and tibial and submental muscles, heart rhythm, eye movements, oximetry, oronasal airflow, abdominal and chest movements, body position. Despite its accuracy, it is a time-consuming and expensive tool. Respiratory polygraphy instead monitors cardiorespiratory function without simultaneously assessing sleep and wakefulness; it is more affordable than PSG, but few paediatric studies compare these techniques and there is optional recommendation in children. Nocturnal oximetry is a simple and accessible exam that has high predictive value only for children at high risk. The daytime nap PSG, despite the advantage of shorter duration and lower costs, is not accurate for predicting SDB. Few paediatric data support the use of home testing during sleep. Finally, laboratory biomarkers and radiological findings are potentially useful hallmarks of SDB, but further investigations are needed to standardise their use in clinical practice.

Are the severity of obstruction and the apnea-hypopnea index related to orofacial anatomy in children with obstructive sleep apnea? a kinetic MRI study

OBJECTIVES

The proportionality between anatomical characteristics and disease severity in children and adolescents with obstructive sleep apnea (OSA) has not been well characterized. The present study investigated the relationship between the dentoskeletal and oropharyngeal features of young patients with OSA and either the apnea-hypopnea index (AHI) or the amount of upper airway obstruction.

METHODS

MRI of 25 patients (8- to 18-year-old) with OSA (mean AHI = 4.3 events/h) was retrospectively analyzed. Sleep kinetic MRI (kMRI) was used to assess airway obstruction, and static MRI (sMRI) was used to assess dentoskeletal, soft tissue, and airway parameters. Factors related to AHI and obstruction severity were identified with multiple linear regression (significance level α = 0.05).

RESULTS

As evidenced by kMRI, circumferential obstruction was present in 44% of patients, while laterolateral and anteroposterior was present in 28%; as evidenced by kMRI, obstructions were retropalatal in 64% of cases and retroglossal in 36% (no nasopharyngeal obstructions); kMRI showed a higher prevalence of retroglossal obstructions compared to sMRI(p = 0.037); the main obstruction airway area was not related to AHI; the maxillary skeletal width was related to AHI (β = -0.512, p = 0.007) and obstruction severity (β = 0.625, p = 0.002); and the retropalatal width was related to AHI (β = -0.384, p = 0.024) and obstruction severity (β = 0.519, p = 0.006).

CONCLUSIONS

In children and adolescents, the severity of OSA and obstruction were inversely proportional to the maxillary basal width and retropalatal airway width. Further studies are needed to assess the benefits of targeted clinical treatments widening the transverse dimension of these structures.

A biophysiological framework exploring factors affecting speech and swallowing in clinical populations: focus on individuals with Down syndrome

Speech and swallowing are complex sensorimotor behaviors accomplished using shared vocal tract anatomy. Efficient swallowing and accurate speech require a coordinated interplay between multiple streams of sensory feedback and skilled motor behaviors. Due to the shared anatomy, speech and swallowing are often both impacted in individuals with various neurogenic and developmental diseases, disorders, or injuries. In this review paper, we present an integrated biophysiological framework for modeling how sensory and motor changes alter functional oropharyngeal behaviors of speech and swallowing, as well as the potential downstream effects to the related areas of language and literacy. We discuss this framework with specific reference to individuals with Down syndrome (DS). Individuals with DS experience known craniofacial anomalies that impact their oropharyngeal somatosensation and skilled motor output for functional oral-pharyngeal activities such as speech and swallowing. Given the increased risk of dysphagia and "silent" aspiration in individuals with DS, it is likely somatosensory deficits are present as well. The purpose of this paper is to review the functional impact of structural and sensory alterations on skilled orofacial behaviors in DS as well as related skills in language and literacy development. We briefly discuss how the basis of this framework can be used to direct future research studies in swallowing, speech, and language and be applied to other clinical populations.

Role of neck radiography in assessing recurrent/residual adenoid hypertrophy in children with OSA and history of adenotonsillectomy: a sleep physician perspective

STUDY OBJECTIVES

Recurrent/residual adenoid hypertrophy after adenotonsillectomy in children can result in obstructive sleep apnea (OSA). We aimed to assess the role of soft tissue neck X-ray (STN-XR) in evaluating recurrent/residual adenoid tissue hypertrophy.

METHODS

This was a single-center retrospective study that included children with sleep study-confirmed OSA and a known history of adenotonsillectomy who underwent STN-XR to evaluate for recurrent/residual adenoid tissue hypertrophy. STN-XR nasopharyngeal obliteration and baseline polysomnographic data were analyzed. Multiple linear regression was used to assess the independent relationship between the results of STN-XR and the total apnea-hypopnea index, while controlling for relevant characteristics.

RESULTS

The study included 160 participants with a median age of 10 years (quartile [Q] 1 = 7, Q3 = 12.25). More than half of the children were male (59.4%) and the median body mass index z-score was 2.11 (Q1 = 1.23, Q3 = 2.54). STN-XR was normal in 39.4%, and it showed mild, moderate, and complete nasopharyngeal obliteration in 20.6%, 32.5%, and 7.5% of the participants, respectively. Multiple regression analysis showed that moderate and complete nasopharyngeal obliteration was associated with an increase in the mean total apnea-hypopnea index by 109% (P = .0002) and 185% (P = .001), respectively, when compared with children without nasopharyngeal obliteration. However, mild nasopharyngeal obliteration, body mass index z-score, age, sex, and race were not significantly associated with an increase in the total apnea-hypopnea index.

CONCLUSIONS

STN-XR was useful in assessing recurrent/residual adenoid tissue hypertrophy in children with OSA and a history of adenotonsillectomy. Moderate and complete nasopharyngeal obliteration were associated with significantly increased apnea-hypopnea index. Pediatric sleep physicians may consider STN-XR in the evaluation of children with OSA and previous history of adenotonsillectomy.

CITATION

Senthilvel E, Nguyen QL, Gunaratnam B, Feygin YB, Palani R, El-Kersh K. Role of neck radiography in assessing recurrent/residual adenoid hypertrophy in children with OSA and history of adenotonsillectomy: a sleep physician perspective. J Clin Sleep Med. 2023;19(6):1027-1033.

Sleep Endoscopy and Cine Magnetic Resonance Imaging Evaluation of Children With Persistent Obstructive Sleep Apnea

OBJECTIVE

To compare findings of same-day cine magnetic resonance imaging (MRI) and drug-induced sleep endoscopy (DISE) and examine how each technique uniquely contributes to the evaluation of persistent obstructive sleep apnea following adenotonsillectomy.

STUDY DESIGN

Retrospective cohort study.

SETTING

Quaternary care center.

METHODS

Chart review was performed for consecutive patients who underwent same-day cine MRI and DISE between 2015 and 2020. Descriptive statistics are reported, and Cohen kappa coefficients were calculated to evaluate the agreement between cine MRI and DISE for obstruction at the adenoids, lingual tonsils, and tongue base.

RESULTS

There were 137 patients, the mean age was 10.4 years (95% CI, 3.2-16.7), and 62.8% were male. The most common sites of obstruction on DISE were the tongue base (86.9%), velum (78.7%), epiglottis (74.5%), inferior turbinate (68.6%), and lingual tonsil (61.3%). The most common sites of obstruction on cine MRI were the hypopharynx (56.3%), tongue base (44.8%), lingual tonsil (38.0%), and macroglossia (37.6%). There was moderate agreement for adenoid hypertrophy (κ = 0.53) and poor agreement for lingual tonsil hypertrophy (κ = 0.15) and tongue base obstruction (κ = 0.09). DISE identified more instances of multilevel obstruction when compared with cine MRI (94.9% vs 48.2%).

CONCLUSION

DISE offered a better examination of nasal and supraglottic obstruction and is sensitive to partial vs complete collapse, while cine MRI offered better soft tissue resolution for lymphoid tissue hypertrophy and provided a global view of primary and secondary airway obstruction. Cine MRI and DISE are complementary modalities in the evaluation of children with persistent obstructive sleep apnea.

Can Dynamic Magnetic Resonance Images Improve Prenatal Diagnosis of Robin Sequence

BACKGROUND

Robin sequence (RS) is a triad of micrognathia, glossoptosis, and airway obstruction. Prenatal diagnosis of RS improves delivery planning and postnatal care, but the process for prenatal diagnosis has not been refined. The purpose of this study was to determine if dynamic cine magnetic resonance imaging (MRI) can improve the reliability of prenatal diagnosis for RS compared to current static imaging techniques.

MATERIALS AND METHODS

This is a retrospective cross-sectional study including fetuses with prenatal MRIs obtained in a single center from January 2014 to November 2019. Fetuses were included if they: 1) had a prenatal MRI with cine dynamic sequences of adequate quality, 2) were live born, and 3) had postnatal craniofacial evaluation to confirm RS. Patients without postnatal confirmation of their prenatal findings were excluded. The primary predictor variable was imaging type (cine or static MRI). Outcome variables were tongue and airway measurements: 1) tongue height, 2) length and width, 3) tongue shape index, 4) observation of tongue touching the posterior pharyngeal wall, and 5) measurement of oropharyngeal space. All measurements were made independently on the cine images and on static MRI sequences for the same cohort of subjects by a pediatric radiologist. Data were analyzed using paired samples t tests and Fisher exact tests, and significance was set as P < .05.

RESULTS

A total of 11 patients with RS were included in the study. The smallest airway space consistently demonstrated complete collapse on the cine series compared to partial collapse on static images (0 mm vs 1.7 ± 1.4 mm, P = .002). No other imaging variable was statistically significantly different between techniques.

CONCLUSIONS

Cine imaging sequences on prenatal MRI were superior to static images in discerning complete collapse of the smallest airway space, an important marker of RS. This suggests a possible benefit to adding dynamic MRI evaluation for prenatal diagnosis of this condition.

Smartphone videos to predict the severity of obstructive sleep apnoea

OBJECTIVE

Diagnosis of obstructive sleep apnoea (OSA) is made on overnight polysomnography (PSG). Given the widespread availability of smartphone video technology, we aimed to develop and test a standardised scoring system for smartphone videos and compare these scores to PSG results.

METHODS

Children aged 1-16 years undergoing PSG for suspected OSA were included. Parents were asked to take 1-2 min videos of the breathing they were concerned about. Videos were scored using a newly developed and tested tool on five components: inspiratory obstructive noises (1-4), presence of obstructive events (0-1), increased work of breathing (0-1), mouth breathing (0-1) and neck extension (0-1). Video scores and the Obstructive Apnoea Hypopnoea Index (OAHI) were compared using Spearman correlation. Sensitivity, specificity, positive predictive value and negative predictive value were calculated for different cut-off scores to achieve the best results.

RESULTS

Videos from 43 children (28 men (65.1%), median age 5.7 years (range 2.6-14.0 years), median OAHI 3.8/hour (range 0-82 events/hour) were included. Nine children (20.9%) had a video score of <3, all of whom had an OAHI of ≤5 events/hour. For a video score of ≥3, sensitivity was 100%; specificity was 36%; positive predictive value was 53%; and negative predictive value 100% for moderate to severe OSA (OAHI>5 events/hour) .

CONCLUSION

We have developed and validated a simple clinical tool (the Monash Obstructive Sleep Apnoea Video Score) to quantify abnormalities in breathing seen on short video recordings made on a smartphone. A low score rules out moderate-severe OSA and may be valuable in the triage of children with symptoms of OSA.

Predicting critical closing pressure in children with obstructive sleep apnea using fluid-structure interaction

Surgical treatment of obstructive sleep apnea (OSA) in children requires knowledge of upper airway dynamics, including the closing pressure (Pcrit), a measure of airway collapsibility. We applied a flow-structure interaction (FSI) computational model to estimate Pcrit in patient-specific upper airway models obtained from magnetic resonance imaging (MRI) scans. We sought to examine the agreement between measured and estimated Pcrit from FSI models in children with Down syndrome. We hypothesized that the estimated Pcrit would accurately reflect measured Pcrit during sleep and therefore reflect the severity of OSA as measured by the obstructive apnea-hypopnea index (AHI). All participants (n = 41) underwent polysomnography and sedated sleep MRI scans. We used Bland-Altman plots to examine the agreement between measured and estimated Pcrit. We determined associations between estimated Pcrit and OSA severity, as measured by AHI, using regression models. The agreement between passive and estimated Pcrit showed a fixed bias of -1.31 [confidence interval (CI) = -2.78, 0.15] and a nonsignificant proportional bias. A weaker agreement with active Pcrit was observed. A model including AHI, gender, an interaction term for AHI, and gender and neck circumference explained the largest variation (R2 = 0.61) in the relationship between AHI and estimated Pcrit (P < 0.0001). Overlap between the areas of the airway with the lowest stiffness, and areas of collapse on dynamic MRI, was 77.4 ± 30% for the nasopharyngeal region and 78.6 ± 33% for the retroglossal region. The agreement between measured and estimated Pcrit and the significant association with AHI supports the validity of Pcrit estimates from the FSI model.NEW & NOTEWORTHY We present a noninvasive method for estimating critical closing pressure (Pcrit) using fluid-structure interaction (FSI) simulations and magnetic resonance imaging (MRI) scans in patients with obstructive sleep apnea (OSA). We used patient-specific stiffness measures in our FSI model to account for any individual variability in the elasticity of soft tissues surrounding the upper airway. We validated this model by measuring the degree of agreement between measured and estimated Pcrit.

Pediatric drug-induced sleep endoscopy: An updated review of the literature

The field of drug-induced sleep endoscopy (DISE) has grown considerably over the last 10∼15 years, to now include its use in pediatric patients. In this review article, we outline our approach to the use of this technology in Children with Airway Obstruction, most specifically in the management of children with airway obstruction and known or suspected adenotonsillar enlargement.

Effect of sleep on upper airway dynamics in obese adolescents with obstructive sleep apnea syndrome

STUDY OBJECTIVES

The biomechanical basis of obstructive sleep apnea syndrome (OSAS) may influence upper airway dynamics. In this study, we investigate dynamic changes during respiration in wakefulness and sleep in obese adolescents with and without OSAS.

METHODS

Respiratory-gated dynamic magnetic resonance imaging (MRI) at the retropalatal and retroglossal regions was performed with simultaneous measurement of SpO2 and nasal-oral mask airflow and pressure. Airway cross-sectional area (CSA) was determined using AMIRA. Percent change in CSA was calculated from five continuous tidal breaths in states of wakefulness and sleep. Mixed effects models were used to evaluate interactions between group (OSAS/control), site (retropalatal/retroglossal), and stage (wake/sleep).

RESULTS

We studied 24 children with OSAS (mean age 15.49 ± 2.00 years, mean apnea-hypopnea index [AHI] 16.53 ± 8.72 events/h) and 19 controls (mean age 14.86 ± 1.75 years, mean AHI 2.12 ± 1.69 events/h). Groups were similar in age, sex, height, weight, and BMI Z-score. Participants with OSAS had a 48.17% greater increase in percent change of airway CSA during sleep than controls (p < 0.0001), while there was no difference between groups during wakefulness (p = 0.6589). Additionally, participants with OSAS had a 48.80% increase in percent change of airway CSA during sleep as compared with wakefulness (p < 0.0001), whereas no such relationship was observed in controls (p = 0.5513).

CONCLUSIONS

This study demonstrates significant effects of sleep on upper airway dynamics in obese children with OSAS. Dynamic MRI with physiological data can potentially provide further insight into the biomechanical basis of OSAS and assist in more effective management.

Evaluation of Upper Airway in Children with Obstructive Sleep Apnea Using Cone-Beam Computed Tomography

OBJECTIVE

Cone-beam computed tomography (CBCT) offers three-dimensional structures in assessing upper airway of patients. This study aims to compare the cone-beam computerized tomography scan measurements between children with obstructive sleep apnea (OSA) and primary snoring.

STUDY DESIGN

Case-control study.

METHODS

This prospective study was conducted in a tertiary referral center. Thirty-six children with moderate-to-severe OSA (with apnea-hypopnea index [AHI] > 5 events/hour) and 36 age-, gender-, and obesity-matched children with primary snoring (AHI <1) were enrolled. The measurements in CBCT parameters were compared between children with moderate-to-severe OSA and primary snorers by conditional logistic regression model.

RESULTS

A total of 72 children (mean age, 7.9 ± 2.8 years; 64% male) were included. Children with moderate-to-severe OSA had a significantly smaller nasopharyngeal (2900 ± 1400 vs. 3800 ± 1800 mm³ , P = .017) and oropharyngeal airway volume (5600 ± 2700 vs. 7400 ± 4000 mm³ , P = .026) than those with primary snoring. Children with moderate-to-severe OSA, as compared to primary snorers, also had a significantly smaller minimal airway area in nasopharynx (77.4 ± 37.7 vs. 107.7 ± 52.0 mm² , P = .006) and oropharynx (66.6 ± 61.9 vs. 101.6 ± 65.8 mm² , P = .023). Moreover, the airway length was not significantly different between children with moderate-to-severe OSA and primary snoring.

CONCLUSIONS

The three-dimensional CBCT airway analysis could be used as a useful tool to evaluate upper airway in children with OSA.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:680-685, 2021.

Role of dynamic sleep MRI in obstructive sleep apnea syndrome

PURPOSE

To identify obstruction sites of the upper airway during sleep in patients with obstructive sleep apnea syndrome (OSAS) under dynamic conditions and improve knowledge to guide surgical treatment and advancements.

MATERIALS AND METHODS

The study included 15 patients (5 females and 10 males) who were diagnosed as having OSAS. Overall mean age was 40.2 years (± 7.01 years). All the patients underwent drug-induced sleep endoscopy (DISE) and dynamic sleep MRI. The presence, location, and direction of airway collapse were assessed. Dynamic MRI findings were correlated to DISE. Data of the site and direction of airway collapse were correlated with those of endoscopic findings and interobserver agreement was done.

RESULTS

The dynamic images in sagittal section showed collapse of the upper airway at retropalatal level in 14 patients (93.33%) and at retroglossal level in seven patients (46.7%) and of these 14 patients; seven had combined retropalatal and retroglossal collapse. These findings were highly correlated with DISE findings with an excellent interobserver agreement for retropalatal and retroglossal levels (Kappa = 1 and 0.867, P value = 0.000), respectively. Objective measurements of the direction of collapse in axial dynamic sleep MRI images showed significant statistical correlation with endoscopic findings regarding retropalatal anteroposterior and circumferential collapse (Kappa = 0.58 and 0.52, P value = 0.02 and 0.03, respectively).

CONCLUSION

Dynamic sleep MRI can reliably characterize the actual site of dynamic airway obstruction and has the potential of improving predictions of successful surgical outcomes in OSAS patients.

Evaluation and Management of Children with Obstructive Sleep Apnea Syndrome

Obstructive sleep apnea syndrome (OSAS) is a common pediatric disorder characterized by recurrent events of partial or complete upper airway obstruction during sleep which result in abnormal ventilation and sleep pattern. OSAS in children is associated with neurobehavioral deficits and cardiovascular morbidity which highlights the need for prompt recognition, diagnosis, and treatment. The purpose of this state-of-the-art review is to provide an update on the evaluation and management of children with OSAS with emphasis on children with complex medical comorbidities and those with residual OSAS following first-line treatment. Proposed treatment strategies reflecting recommendations from a variety of professional societies are presented. All children should be screened for OSAS and those with typical symptoms (e.g., snoring, restless sleep, and daytime hyperactivity) or risk factors (e.g., neurologic, genetic, and craniofacial disorders) should undergo further evaluation including referral to a sleep specialist or pediatric otolaryngologist and overnight polysomnography, which provides a definitive diagnosis. A cardiology and/or endocrinology evaluation should be considered in high-risk children. For the majority of children, first-line treatment is tonsillectomy with or without adenoidectomy; however, some children exhibit multiple levels of airway obstruction and may require additional evaluation and management. Anti-inflammatory medications, weight loss, and oral appliances may be appropriate in select cases, particularly for mild OSAS. Following initial treatment, all children should be monitored for residual symptoms and polysomnography may be repeated to identify persistent disease, which can be managed with positive airway pressure ventilation and additional surgical approaches if required.

The spectrum of obstructive sleep apnea in infants and children with Down Syndrome

OBJECTIVE

Describe the spectrum of OSA across time in infants and children with Down syndrome.

METHODS

Retrospective records review of children who underwent formal polysomnography (PSG) in one of two Australian tertiary sleep centres over selected 3.5-year periods. 152 children were identified, then all sleep study and treatment records were retrieved for the lifetime of the child through 2018.

RESULTS

3.8 ± 3.2 studies (range 1-17) were retrieved per child and 38.2% had mild disease at worst. Children having only 1 study were more likely to have a normal or mild result than those having ≥2 (chi-square 11.25, p-value 0.0008) Studies were more often severe in children age <2 compared to those ≥2 years, (chi-square 12.87, p = 0.005). After age 2 years, OSA severity increased with age. Amongst 91 (56.4%) children with ≥2 studies, 71 (78.0%) had moderate or severe disease at some time. Studies evaluating the effects of surgery (most often adenotonsillectomy) showed resolution of disease to mild or normal in 53.3%. Where ≥2 studies were evaluated, the last study polarised towards normal or mild disease 40 (44.0%), or treatment titrations 34 (37.4%) with moderate or severe disease in 17 (18.7%).

CONCLUSIONS

In a tertiary sleep unit, a full spectrum of sleep disordered breathing in Down syndrome was seen from infancy onwards. Children having only one study were more likely to have normal results. Children with multiple studies reflected disease surveillance, including follow-up after treatment interventions.

Long Term Continuous Positive Airway Pressure and Non-invasive Ventilation in Obstructive Sleep Apnea in Children With Obesity and Down Syndrome

This review will focus on non-invasive ventilation (NIV) and continuous positive airway pressure (CPAP) therapy in children with obstructive sleep apnea (OSA) due to obesity and underlying syndromes. These children have a high prevalence of OSA and residual OSA after adenotonsillectomy. Therefore, a high proportion of these children are treated with CPAP or NIV. This review will focus on treatment selection tools and will subsequently cover specific issues on CPAP treatment in obese and syndromic children with a major focus on Down syndrome.

Non-invasive Ventilation and CPAP Failure in Children and Indications for Invasive Ventilation

Non-invasive ventilation (NIV) and continuous positive airway pressure (CPAP) are effective treatments for children with severe sleep disordered breathing (SBD). However, some patients may present too severe SDB that do not respond to NIV/CPAP or insufficient compliance to treatment. A careful revaluation of the interface and of ventilator settings should be performed before considering alternative treatments. In patients with obstructive sleep apnea (OSA), alternatives to CPAP/NIV rely on the underlying disease. Ear-nose-throat (ENT) surgery such as adeno-tonsillectomy (AT), turbinectomy or supraglottoplasty represent an effective treatment in selected patients before starting CPAP/NIV and should be reconsidered in case of CPAP failure. Rapid maxillary expansion (RME) is restricted to children with OSA and a narrow palate who have little adenotonsillar tissue, or for those with residual OSA after AT. Weight loss is the first line therapy for obese children with OSA before starting CPAP and should remain a priority in the long-term. Selected patients may benefit from maxillo-facial surgery such as mandibular distraction osteogenesis (MDO) or from neurosurgery procedures like fronto-facial monobloc advancement. Nasopharyngeal airway (NPA) or high flow nasal cannula (HFNC) may constitute efficient alternatives to CPAP in selected patients. Hypoglossal nerve stimulation has been proposed in children with Down syndrome not tolerant to CPAP. Ultimately, tracheostomy represents the unique alternative in case of failure of all the above-mentioned treatments. All these treatments require a multidisciplinary approach with a personalized treatment tailored on the different diseases and sites of obstruction. In patients with neuromuscular, neurological or lung disorders, non-invasive management in case of NIV failure is more challenging. Diaphragmatic pacing has been proposed for some patients with central congenital hypoventilation syndrome (CCHS) or neurological disorders, however its experience in children is limited. Finally, invasive ventilation via tracheotomy represents again the ultimate alternative for children with severe disease and little or no ventilatory autonomy. However, ethical considerations weighting the efficacy against the burden of this treatment should be discussed before choosing this last option.

Updates on management of pediatric obstructive sleep apnea

Obstructive sleep apnea (OSA) affects about 1%-5% of the pediatric population. The consequences of untreated OSA in children include neurocognitive deficits, behavioral problems, poor school performance as well as systemic and pulmonary hypertension. The treatment options for pediatric OSA are numerous with a variety of surgical and non-surgical interventions. As our understanding of the complexities of OSA grows, the options for management have continued to expand as well. The objectives of this review are to describe the commonly prescribed treatments for pediatric OSA including adenotonsillectomy as well as use of positive airway pressure. We also highlight other surgical and non-surgical interventions available. In addition, we provide updates on current research focusing on newer diagnostic and experimental treatment modalities.

Upper airway visualization in pediatric obstructive sleep apnea

Pediatric Obstructive Sleep Apnea (OSA) is a condition that may lead to a variety of comorbidities in adolescence and adulthood. The gold standard of diagnosing OSA is polysomnography (PSG). Over the past fifteen years numerous publications have explored how to better visualize the upper airway to further assess OSA in the pediatric population, and eventually institute personalized treatment. Lateral neck radiograph, cephalometry, computed axial tomography, and magnetic resonance imaging are all unique imaging techniques that are used in the diagnosis of OSA. Drug Induced Sleep Endoscopy is a direct visualization technique that is gathering momentum in pediatrics. Each approach has respective benefits and weaknesses. However, none of them at this time can replace PSG. They are a helpful supplement in those patients with complicated upper airway anatomy and in those with residual OSA.

Managing the Child with Persistent Sleep Apnea

Pediatric obstructive sleep apnea (OSA) affects 2% to 4% of American children, and is associated with metabolic, cardiovascular, and neurocognitive sequelae. The primary treatment for pediatric OSA is adenotonsillectomy. Children with obesity, craniofacial syndromes, and severe baseline OSA are at risk for persistent disease. Evaluation of persistent OSA should focus on identifying the causes of upper airway obstruction. Interventions should be tailored to address the patient's symptomatology, sites of obstruction, and preference for surgical versus medical management. Further research is needed to identify management protocols that result in improved outcomes for children with persistent OSA.

Diagnostic techniques and surgical outcomes for persistent pediatric obstructive sleep apnea after adenotonsillectomy: A systematic review and meta-analysis

OBJECTIVE

To evaluate the efficacy of upper airway surgery for children with persistent obstructive sleep apnea after adenotonsillectomy and to assess sleep study outcomes when Drug Induced Sleep Endoscopy, Cine MRI, or other imaging procedure is performed to assist in identifying the location of obstruction and planning surgery.

METHODS

Systematic review and meta-analysis was performed. Inclusion criteria was English-language studies with original data including pediatric patients with persistent OSA after T&A. Exclusion criteria included case reports and lack of pre and post-operative sleep study data. Data Sources were PubMed, Cochrane Central, and Embase from 2000 to 2018. PRISMA standards were followed for the selection and review of articles. The Newcastle-Ottawa Quality Assessment scale was used to score the quality of evidence of the studies. All manuscripts were reviewed independently by two investigators. Primary outcome measures were apnea-hypopnea index and minimum oxygen saturation. Data was pooled using a random-effects model.

RESULTS

Of the 1902 abstracts identified, 11 studies (214 patients) met inclusion criteria for systematic review, 5 with Drug Induced Sleep Endoscopy as the diagnostic technique, 4 with Cine MRI, and 2 with MRI/CT. All studies were case series. Most subjects had syndromic comorbidities and/or obesity. Ten studies (198 patients) were included in the meta-analysis. Overall, there was a change in apnea hypopnea index of -6.51 (95% CI, -8.17 to - 4.85; p < 0.001) and an increase in minimum oxygen saturation by 3.24% (95% CI, 1.49%-4.98%; p < 0.001) following surgical intervention. Both Drug Induced Sleep Endoscopy and Cine MRI directed surgeries resulted in significant improvement in sleep study parameters. The two techniques could not be directly compared due to significant differences in co-morbidity rates between patients.

CONCLUSIONS

Surgery for pediatric persistent obstructive sleep apnea improves apnea hypopnea index and minimum oxygen saturation but does not resolve the disease. This is true when both Drug Induced Sleep Endoscopy and Cine MRI findings were used to direct surgery.

Outcomes of Tongue Base Reduction and Lingual Tonsillectomy for Residual Pediatric Obstructive Sleep Apnea after Adenotonsillectomy

Introduction  Upper airway obstruction at multiple sites, including the velum, the oropharynx, the tongue base, the lingual tonsils, or the supraglottis, has been resulting in residual obstructive sleep apnea (OSA) after tonsillectomy and adenoidectomy (TA). The role of combined lingual tonsillectomy and tongue base volume reduction for treatment of OSA has not been studied in nonsyndromic children with residual OSA after TA. Objective  To evaluate the outcomes of tongue base volume reduction and lingual tonsillectomy in children with residual OSA after TA. Methods  A retrospective chart review was conducted to obtain information on history and physical examination, past medical history, findings of drug-induced sleep endoscopy (DISE), of polysomnography (PSG), and surgical management. Pre- and postoperative PSGs were evaluated to assess the resolution of OSA and to determine the improvement in the obstructive apnea-hypopnea index (oAHI) before and after the surgery. Results  A total of 10 children (5 male, 5 female, age range: 10-17 years old, mean age: 14.5 ± 2.6 years old) underwent tongue base reduction and lingual tonsillectomy. Drug-induced sleep endoscopy (DISE) revealed airway obstruction due to posterior displacement of the tongue and to the hypertrophy of the lingual tonsils. All of the patients reported subjective improvement in the OSA symptoms. All of the patients had improvement in the oAHI. The postoperative oAHI was lower than the preoperative oAHI ( p  < 0.002). The postoperative apnea-hypopnea index during rapid eye movement sleep (REM-AHI) was lower than the preoperative REM-AHI ( p  = 0.004). Obstructive sleep apnea was resolved in children with normal weight. Overweight and obese children had residual OSA. Nonsyndromic children had resolution of OSA or mild OSA after the surgery. Conclusions  Tongue base reduction and lingual tonsillectomy resulted in subjective and objective improvement of OSA in children with airway obstruction due to posterior displacement of the tongue and to hypertrophy of the lingual tonsils.

Effect of a 1-week intense myofunctional training on obstructive sleep apnoea in children with Down syndrome

BACKGROUND

Obstructive sleep apnoea (OSA) is common in children with Down syndrome (DS), yet difficult to treat. As muscular hypotonia of the upper airway may cause OSA and is also common in DS, we tested whether intense myofunctional therapy improves OSA in children with DS.

PATIENTS AND METHODS

Forty-two children underwent cardiorespiratory sleep studies immediately before and after a 1-week intensive training camp consisting of three daily 45 min sessions of myofunctional exercises according to Padovan. Primary outcome was the mixed-obstructive-apnoea/hypopnoea index (MOAHI), secondary outcomes the ≤3% oxygen desaturation index (DI₃), the ≤90% desaturation index (DI₉₀) and the lowest pulse oximeter saturation (SpO_2nadir).

RESULTS

Eighteen recordings had ≥3 hours of artefact-free recording in both the pretreatment and post-treatment sleep study and were therefore included in the analysis. Mean age was 6.3 years (SD 2.5); 83% had OSA prior to intervention. Mean MOAHI was 6.4 (SD 8.6) before and 6.4 (SD 10.8) after the intervention (p>0.05); the DI₃ and SpO_2nadir also did not change. Only the DI₉₀ decreased significantly from 2.7 (SD 4.5) to 2.1 (SD 3.7) (p<0.05).

CONCLUSION

The 1-week intense myofunctional training camp evaluated here in children with DS had only a marginal effect on OSA. Whether a longer follow-up period or duration of intervention would yield stronger effects remains to be determined.

Magnetic resonance imaging of obstructive sleep apnea in children

Sleep-disordered breathing has a spectrum of severity that spans from snoring and partial airway collapse with increased upper airway resistance, to complete upper airway obstruction with obstructive sleep apnea during sleeping. While snoring occurs in up to 20% of children, obstructive sleep apnea affects approximately 1-5% of children. The obstruction that occurs in obstructive sleep apnea is the result of the airway collapsing during sleep, which causes arousal and impairs restful sleep. Adenotonsillectomy is the first-line treatment of obstructive sleep apnea and is usually effective in otherwise healthy nonsyndromic children. However, there are subgroups in which this surgery is less effective. These subgroups include children with obesity, severe obstructive sleep apnea preoperatively, Down syndrome, craniofacial anomalies and polycystic ovarian disease. Continuous positive airway pressure (CPAP) is the first-line therapy for persistent obstructive sleep apnea despite previous adenotonsillectomy, but it is often poorly tolerated by children. When CPAP is not tolerated or preferred by the family, surgical options beyond adenotonsillectomy are discussed with the parent and child. Dynamic MRI of the airway provides a means to identify and localize the site or sites of obstruction for these children. In this review the authors address clinical indications for imaging, ideal team members to involve in an effective multidisciplinary program, basic anesthesia requirements, MRI protocol techniques and interpretation of the findings on MRI that help guide surgery.

[A specialised consultation for children and young adults with trisomy 21]

The life expectancy of people with trisomy 21 has increased over recent decades. More than half live over 55 years today, compared to just 9 years in 1929. This progress is thanks to easier access to care and improved medical diagnoses as well as greater physical and psychological stimulation. Continued monitoring remains essential but it becomes less systematic as children grow up, despite the risk of certain complications increasing from puberty. Consultations devoted to trisomy 21 aim to facilitate access to care through an adapted care pathway.

The Role of Functional Respiratory Imaging in Treatment Selection of Children With Obstructive Sleep Apnea and Down Syndrome

STUDY OBJECTIVES

The complexity of the pathogenesis of obstructive sleep apnea (OSA) in children with Down syndrome (DS) is illustrated by a prevalence of residual OSA after adenotonsillectomy. The aim of this study was to investigate whether upper airway imaging combined with computation fluid dynamics could characterize treatment outcome after adenotonsillectomy in these children.

METHODS

Children with DS and OSA were prospectively included. All children underwent an evaluation of the upper airway and an ultra-low dose computed tomography scan of the upper airway before adenotonsillectomy. The upper airway tract was extracted from the scan and combined with computational fluid dynamics. Results were evaluated using control polysomnography after adenotonsillectomy.

RESULTS

Thirty-three children were included: 18 boys, age 4.3 ± 2.3 years, median body mass index z-score 0.6 (-2.9 to 3.0), and median obstructive apnea-hypopnea index was 15.7 (3-70) events/h. The minimal upper airway cross-sectional area was significantly smaller in children with more severe OSA (P = .03). Nineteen children underwent a second polysomnography after adenotonsillectomy. Seventy-nine percent had persistent OSA (obstructive apneahypopnea index > 2 events/h). A greater than 50% decrease in obstructive apnea-hypopnea index was observed in 79% and these children had a significantly higher volume of the regions below the tonsils.

CONCLUSIONS

This is the first study to characterize treatment outcome in children with DS and OSA using computed tomography upper airway imaging. At baseline, children with more severe OSA had a smaller upper airway. Children with a less favorable response to adenotonsillectomy had a smaller volume of regions below the tonsils, which could be due to enlargement of the lingual tonsils, glossoptosis, or macroglossia.

COMMENTARY

A commentary on this article appears in this issue on page 501.

An updated review of pediatric drug-induced sleep endoscopy

Objectives

Drug-induced sleep endoscopy (DISE) involves assessment of the upper airway using a flexible endoscope while patients are in a pharmacologically-induced sleep-like state. The aim of this article is to review the current literature regarding the role of DISE in children with obstructive sleep apnea (OSA). The indications, typical anesthetic protocol, comparison to other diagnostic modalities, scoring systems, and outcomes are discussed.

Methods

A comprehensive review of literature regarding pediatric DISE up through May 2017 was performed.

Results

DISE provides a thorough evaluation of sites of obstruction during sedation. It is typically indicated for children with persistent OSA after tonsillectomy, those with OSA without tonsillar hypertrophy, children with risk factors predisposing then to multiple sites of obstruction, or when sleep-state dependent laryngomalacia is suspected. The dexmedotomidine and ketamine protocol, which replicates non-REM sleep, appears to be safe and is often used for pediatric DISE, although propofol is the most commonly employed agent for DISE in adults. Six different scoring systems (VOTE, SERS, Chan, Bachar, Fishman, Boudewyns) have been used to report pediatric DISE findings, but none is universally accepted.

Conclusions

DISE is a safe and useful technique to assess levels of obstruction in children. There is currently no universally-accepted anesthetic protocol or scoring system for pediatric DISE, but both will be necessary in order to provide a consistent method to report findings, enhance communication among providers and optimize surgical outcomes.

Level of Evidence

N/A.

Lingual Tonsillectomy for Treatment of Pediatric Obstructive Sleep Apnea: A Meta-analysis

Importance

Evidence indicates correlations between lingual tonsil hypertrophy and pediatric obstructive sleep apnea (OSA). However, to our knowledge, a meta-analysis of surgical outcomes for lingual tonsillectomy in children with OSA has not been conducted.

Objective

To evaluate the therapeutic outcomes of lingual tonsillectomy for treatment of pediatric OSA.

Data Sources

The study protocol was registered on PROSPERO (CRD42015027053). PubMed, MEDLINE, EMBASE, and the Cochrane Reviews databases were searched independently by 2 authors for relevant articles published by September 2016.

Study Selection

The literature search identified English-language studies that used polysomnography to evaluate children with lingual tonsil hypertrophy and OSA after lingual tonsillectomy alone. The search keywords were lingual tonsil, lingual tonsillectomy, sleep endoscopy, sleep apnea, and child.

Data Extraction and Synthesis

Polysomnographic data from each study were extracted. A random-effects model pooled postoperative sleep variable changes and success rates for lingual tonsillectomy in treating pediatric OSA.

Main Outcomes and Measures

Four outcomes for lingual tonsillectomy were analyzed. These included net postoperative changes in the apnea-hypopnea index (AHI), net postoperative changes in the minimum oxygen saturation, the overall success rate for a postoperative AHI less than 1, and the overall success rate for a postoperative AHI less than 5.

Results

This meta-analysis consisted of 4 studies (mean sample size, 18.25 patients), with a total of 73 unique patients (mean [SD] age, 8.3 [1.1] years). Fifty-nine percent (27 of 46) of the patients were male, and 1 of the 4 studies did not specify number of males. Lingual tonsillectomy was indicated for persistent OSA after adenotonsillectomy in all cases. Lingual tonsil hypertrophy was evaluated using computed tomography or magnetic resonance imaging in 1 study, sleep endoscopy in 2 studies, and cine magnetic resonance imaging in 1 study. The mean change in the AHI after lingual tonsillectomy was a reduction of 8.9 (95% CI, -12.6 to -5.2) events per hour. The mean change in the minimum oxygen saturation after lingual tonsillectomy was an increase of 6.0% (95% CI, 2.7%-9.2%). The overall success rate was 17% (95% CI, 7%-35%) for a postoperative AHI less than 1 and 51% (95% CI, 25%-76%) for a postoperative AHI less than 5. Postoperative complications that developed included airway obstruction, bleeding, and pneumonia.

Conclusions and Relevance

Lingual tonsillectomy is an effective surgical management for children with OSA caused by lingual tonsil hypertrophy, and it achieves significant improvement in the AHI and the minimum oxygen saturation. However, children frequently have residual OSA after lingual tonsillectomy, and postoperative complications must be carefully managed.

Upper Airway Reflexes are Preserved During Dexmedetomidine Sedation in Children With Down Syndrome and Obstructive Sleep Apnea

STUDY OBJECTIVES

The assessment of pharyngeal collapsibility is difficult to perform in children under normal sleep. An alternative is to perform the assessment under an anesthetic, such as dexmedetomidine (DEX), that induces non-rapid eye movement (NREM) sleep. The objectives of this study were to compare critical closing airway pressure (Pcrit) obtained during natural sleep to that obtained under DEX in patients with Down syndrome (DS) and persistent obstructive sleep apnea (OSA) and determine whether Pcrit measured under sedation predicts the severity of OSA.

METHODS

The passive and active Pcrit, which represent airway passive mechanical properties and active dynamic responses to airway obstruction, respectively, were measured. Upper airway reflex activity was estimated by calculating the difference between active and passive Pcrit. Subjects underwent overnight polysomnography during which Pcrit was measured during normal sleep. Pcrit was also measured during DEX sedation at a dose of 2 μg/kg/h.

RESULTS

The study included 50 patients with median age of 11.4 years (interquartile range: 7.0-13.9) and median body mass index of 23.0 kg/m² (interquartile range: 18.4-29.1), 66% male and 80% Caucasian. Passive Pcrit was significantly higher than active Pcrit when measured during normal sleep and DEX-induced sleep. There was a positive association between apnea-hypopnea index and passive Pcrit (Spearman r = 0.53, P = .0001) and active Pcrit (r = 0.55, P = .0002) under DEX-induced sleep. There were no significant differences between the Pcrit measurements during natural sleep and during DEX sedation.

CONCLUSION

Patients with OSA can compensate for airway obstruction under DEX-induced sleep. The close association between Pcrit and apnea-hypopnea index suggests that airway responses with DEX sedation parallel those seen during natural sleep.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01902407.

Outcome of adenotonsillectomy in children with Down syndrome and obstructive sleep apnoea

OBJECTIVE

To evaluate the outcome of adenotonsillectomy (AT) in a cohort of children with Down syndrome (DS) and obstructive sleep apnoea (OSA).

DESIGN

Retrospective, cross-sectional study.

SETTING

Tertiary care centre.

PATIENTS

Children with DS and OSA, without previous upper airway (UA) surgery.

INTERVENTIONS

AT and full overnight polysomnography.

MAIN OUTCOME RESULTS

A significant improvement of the obstructive apnoea-hypopnoea index (oAHI) after AT was obtained. No differences in sleep efficiency or sleep fragmentation were found postoperatively. Almost half of the children had persistent OSA (oAHI ≥5/hour).

RESULTS

Data are presented as median (lower-upper quartile). Thirty-four children were included, median age 4.0 years (2.7-5.8), body mass index (BMI) z-score 0.81 (-0.46-1.76), and oAHI 11.4/hour (6.5-22.7). The majority presented with severe OSA (58.9%). AT was performed in 22 children, tonsillectomy in 10 and adenoidectomy in two. Postoperatively, a significant improvement of the oAHI was measured from 11.4/hour (6.5-22.7) to 3.6/hour (2.1-9.5) (p=0.001), with a parallel increase of the minimum oxygen saturation (p=0.008). Children with initially more severe OSA had significantly more improvement after UA surgery (p=0.001). Persistent OSA was found in 47.1% of the children.

CONCLUSIONS

AT results in a significant improvement of OSA in children with DS without a change in sleep efficiency or sleep stage distribution. Severe OSA was associated with a larger reduction of OSA severity. Almost half of the children had persistent OSA, which was not correlated to age, gender or BMI z-score.

Pediatric Obstructive Sleep Apnea

Screening for obstructive sleep apnea (OSA) with in-laboratory polysomnography is recommended for children with sleep disordered breathing. Adenotonsillectomy is the first-line therapy for pediatric OSA, although intranasal steroids and montelukast can be considered for those with mild OSA and continuous positive airway pressure for those with moderate to severe OSA awaiting surgery, poor surgical candidates or persistent OSA. Bony or soft tissue upper airway surgery is reasonable for children failing medical management or those with persistent OSA following adenotonsillectomy. Weight loss and oral appliance therapy are also useful. A multi-modality approach to diagnosis and treatment is preferred.

Dynamic Volume Computed Tomography Imaging of the Upper Airway in Obstructive Sleep Apnea

STUDY OBJECTIVES

To describe a dynamic three-dimensional (3D) computed tomography (CT) technique for the upper airway and compare the required radiation dose to that used for common clinical studies of a similar anatomical area, such as for subjects undergoing routine clinical facial CT.

METHODS

Dynamic upper-airway CT was performed on eight subjects with persistent obstructive sleep apnea, four of whom were undergoing magnetic resonance imaging and an additional four subjects who had a contraindication to magnetic resonance imaging. This Health Insurance Portability and Accountability Act-compliant study was approved by our institutional review board, and informed consent was obtained. The control subjects (n = 41) for comparison of radiation dose were obtained from a retrospective review of the clinical picture-archiving computer system to identify 10 age-matched patients per age-based control group undergoing facial CT.

RESULTS

Dynamic 3D CT can be performed with an effective radiation dose of less than 0.38 mSv, a dose that is less than or comparable to that used for clinical facial CT. The resulting data- set is a uniquely complete, dynamic 3D volume of the upper airway through a full respiratory cycle that can be processed for clinical and modeling analyses.

CONCLUSIONS

A dynamic 3D CT technique of the upper airway is described that can be performed with a clinically reasonable radiation dose and sets a benchmark for future use.

How do we recognize the child with OSAS?

Obstructive sleep-disordered breathing includes a spectrum of clinical entities with variable severity ranging from primary snoring to obstructive sleep apnea syndrome (OSAS). The clinical suspicion for OSAS is most often raised by parental report of specific symptoms and/or abnormalities identified by the physical examination which predispose to upper airway obstruction (e.g., adenotonsillar hypertrophy, obesity, craniofacial abnormalities, neuromuscular disorders). Symptoms and signs of OSAS are classified into those directly related to the intermittent pharyngeal airway obstruction (e.g., parental report of snoring, apneic events) and into morbidity resulting from the upper airway obstruction (e.g., increased daytime sleepiness, hyperactivity, poor school performance, inadequate somatic growth rate or enuresis). History of premature birth and a family history of OSAS as well as obesity and African American ethnicity are associated with increased risk of sleep-disordered breathing in childhood. Polysomnography is the gold standard method for the diagnosis of OSAS but may not be always feasible, especially in low-income countries or non-tertiary hospitals. Nocturnal oximetry and/or sleep questionnaires may be used to identify the child at high risk of OSAS when polysomnography is not an option. Endoscopy and MRI of the upper airway may help to identify the level(s) of upper airway obstruction and to evaluate the dynamic mechanics of the upper airway, especially in children with combined abnormalities. Pediatr Pulmonol. 2017;52:260-271. © 2016 Wiley Periodicals, Inc.

Drug-induced sedation endoscopy in surgically naive children with Down syndrome and obstructive sleep apnea

OBJECTIVE

To describe the pattern of upper airway (UA) obstruction in surgically naive children with Down syndrome and obstructive sleep apnea (OSA), and to evaluate the outcome of drug-induced sedation endoscopy (DISE)-directed treatment.

METHODS

A prospective study of DISE in surgically naive children with Down syndrome and OSA was performed. Treatment was individually tailored based on the DISE findings and was evaluated by control polysomnography (PGS). Results are presented as median (lower-upper quartile) unless otherwise stated.

RESULTS

In 41 children, aged 4.2 years (range, 2.8-6.0) with a body mass z score of 1.04 (-0.55 to 1.82) and obstructive apnea-hypopnea index (oAHI) of 10.1/h (range, 6.3-23.0), DISE was performed. Adeno-/tonsillar obstruction was found in 75.6% of the patients, and these patients subsequently underwent UA surgery. Seven patients were non-surgically treated, and three received a combined treatment. A multilevel collapse was present in 85.4%. Tongue base obstruction was present in ten patients (24.4%) and epiglottic collapse in 48.8%. Pre- and postoperative PSG data were available for 25 children (adenotonsillectomy, n = 16; tonsillectomy, n = 7; adenoidectomy, n = 2). A significant improvement in oAHI from 11.4/h (range, 7.7-27.0) to 5.5/h (range, 2.1-7.6) was found. Persistent OSA was present in 52% of the children. No significant association between different DISE findings and persistent OSA could be found.

CONCLUSION

Most patients with Down syndrome and OSA present with multilevel collapse on DISE. Adenotonsillectomy results in a significant improvement of the oAHI; however more than half of the patients had persistent OSA, probably due to multilevel collapse. Upper airway evaluation may provide more insights into the pattern of UA obstruction in patients with persistent OSA.

Multimodality assessment of upper airway obstruction in children with persistent obstructive sleep apnea after adenotonsillectomy

OBJECTIVES/HYPOTHESIS

Children with obstructive sleep apnea (OSA) may have multiple sites of upper airway obstruction (UAO). A wide variety of techniques has been used to evaluate UAO. Our aim was to compare findings of cine magnetic resonance imaging (MRI) and drug-induced sleep endoscopy (DISE) in identifying UAO sites in children with persistent OSA after adenotonsillectomy (AT).

STUDY DESIGN

Retrospective chart review.

MATERIAL AND METHODS

The medical records of children who underwent DISE and cine MRI were reviewed. Data pertaining to demographics, past medical history, body mass index, polysomnography, findings of DISE, and cine MRI were obtained.

RESULTS

Fifteen children (11 boys, 4 girls; age range, 7-18 years) were identified. Comorbid conditions were Down syndrome in nine patients, cerebral palsy in one, attention deficit hyperactivity disorder in two, and asthma in three. Severity of OSA was moderate in five, and severe in 10. DISE and cine MRI showed the same UAO site in 10 patients: a single site (tongue) in nine and multiple sites (tongue and oropharynx/lateral walls) in one. DISE showed additional UAO sites undetected by cine MRI in three patients. Cine MRI showed additional UAO sites undetected by DISE in one patient. DISE and cine MRI showed different sites of obstruction in one patient.

CONCLUSIONS

Cine MRI and DISE documented single and multiple sites of UAO in children with persistent OSA after AT. Cine MRI and DISE findings were similar in the majority of the children. Assessment of the sensitivity and specificity of cine MRI and DISE in detecting sites of UAO merits further investigation.

LEVEL OF EVIDENCE

4. Laryngoscope, 127:1224-1230, 2017.

Obstructive Sleep Apnea Resolution in Hypopnea- versus Apnea-Predominant Children after Adenotonsillectomy

OBJECTIVE

Given that 30% to 40% of children have persistent obstructive sleep apnea (OSA) after adenotonsillectomy, we evaluated whether children with hypopnea-predominant OSA were more likely to have complete disease resolution after adenotonsillectomy than those with apnea-predominant disease. We also identified risk factors that might modify the relationship between disease resolution and polysomnographic event type (ie, hypopnea vs apnea).

STUDY DESIGN

Case series with chart review.

SETTING

Tertiary pediatric hospital.

SUBJECTS/METHODS

Consecutive 1- to 18-year-old typically developing children diagnosed with OSA from March 2011 to December 2012 underwent adenotonsillectomy and completed pre- and postoperative polysomnography within 1 year of surgery.

RESULTS

Fifty-eight children were included (27 female; mean ± SD: age, 5.6 ± 3.1 years; body mass index z score, 1.1 ± 1.7). Overall, adenotonsillectomy resulted in significant improvement in obstructive apnea-hypopnea index (oAHI) from 23.3 ± 40.0 to 4.3 ± 8.2 events per hour (P < .001), obstructive apnea index (5.1 ± 7.4 to 0.4 ± 0.8, P < .001), and obstructive hypopnea index (oHI; 18.1 ± 37.5 to 3.7 ± 8.1, P < .001). There was complete response (oAHI <1.0 event/h) in 24 of 58 patients (41%) but no difference by event type (P = .11). On univariate analysis, only race, sex, oxygen saturation nadir, and oHI were predictive of response to adenotonsillectomy, while multivariate analysis found that prematurity, age, oxygen saturation nadir, oHI, obstructive apnea index, and oAHI were predictive. Event type was not significant, even in a model controlling for age, race, sex, prematurity, asthma, body mass index, and baseline polysomnographic variables.

CONCLUSION

This small study demonstrated no difference in disease resolution between children with hypopnea- and apnea-predominant OSA who underwent adenotonsillectomy. Additionally, adenotonsillectomy significantly improved OSA in most children, and high preoperative oAHI was associated with persistent postoperative OSA.

Obstructive sleep apnea in children: update on the recognition, treatment and management of persistent disease

Adenotonsillectomy (AT) is the recommended first-line treatment for pediatric obstructive sleep apnea (OSA) in children with adenotonsillar hypertrophy. It is now clearly established that AT results in improvement in the severity of OSA in most children. However, a significant number of OSA children undergoing AT exhibit residual persistent OSA post-surgery. Patients at increased risk of persistent OSA include those with severe disease at initial review, older or obese patients, children with underlying asthma or allergic rhinitis, and those who have concurrent underlying medical conditions, such as Trisomy 21, craniofacial syndromes or cerebral palsy. Here, we aim to highlight recent research findings into those who have persistent OSA disease, and suggest a practical approach to the management of these children.