Effectiveness of pediatric drug-induced sleep endoscopy for REM-predominant obstructive sleep apnea.

STUDY OBJECTIVES: Because dexmedetomidine (DEX)-induced sedation mimics non-rapid eye movement (NREM) sleep, its utility in sedating children with REM-predominant disease is unclear. We sought to determine the effectiveness of pediatric drug-induced sleep endoscopy (DISE) using DEX and ketamine for children with REM-predominant OSA, specifically whether or not at least one site of obstruction could be identified. METHODS: A retrospective case series of children without tonsillar hypertrophy undergoing DISE at a tertiary pediatric hospital from 10/2013 through 9/2015 who underwent subsequent surgery to address OSA with polysomnography (PSG) before and after. RESULTS: We included 56 children, mean age 5.6±5.4 years, age range 0.1-17.4 years, mean BMI 20.3±7.4 kg/m2 (76±29 percentile). At least one site of obstruction was identified in all patients, regardless of REM- or NREM-predominance. The mean obstructive apnea-hypopnea index (oAHI) improved (12.6 ± 10.7 to 9.0 ± 14.0 events/h) in children with REM-predominant (P = 0.013) and NREM-predominant disease (21.3 ± 18.9 to 10.3 ± 16.2 events/h) (P = 0.008). The proportion of children with a postoperative oAHI < 5 was 53% and 55% for REM- and NREMpredominant OSA, respectively. Unlike children with NREM-predominant disease, children with REM-predominant disease had significant improvement in the mean saturation nadir (P < 0.001), total sleep time (P = 0.006), and sleep efficiency (P = 0.015). CONCLUSIONS: For children with OSA without tonsillar hypertrophy, DISE using DEX/ketamine was useful to predict at least one site of obstruction, even for those with REM-predominant OSA. DISE-directed outcomes resulted in significant improvements in mean oAHI, total sleep time, sleep efficiency, saturation nadir, and the proportion with oAHI < 5, after surgery for some children with REM-predominant disease.

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.

Wideband acoustic immittance in children with Down syndrome: prediction of middle-ear dysfunction, conductive hearing loss and patent PE tubes.

OBJECTIVE: The purpose of this study was to evaluate pressurised wideband acoustic immittance (WAI) tests in children with Down syndrome (DS) and in typically developing children (TD) for prediction of conductive hearing loss (CHL) and patency of pressure equalising tubes (PETs). DESIGN: Audiologic diagnosis was determined by audiometry in combination with distortion-product otoacoustic emissions, 0.226 kHz tympanometry and otoscopy. WAI results were compared for ears within diagnostic categories (Normal, CHL and PET) and between groups (TD and DS). STUDY SAMPLE: Children with DS (n = 40; mean age 6.4 years), and TD children (n = 48; mean age 5.1 years) were included. RESULTS: Wideband absorbance was significantly lower at 1-4 kHz in ears with CHL compared to NH for both TD and DS groups. In ears with patent PETs, wideband absorbance and group delay (GD) were larger than in ears without PETs between 0.25 and 1.5 kHz. Wideband absorbance tests were performed similarly for prediction of CHL and patent PETs in TD and DS groups. CONCLUSIONS: Wideband absorbance and GD revealed specific patterns in both TD children and those with DS that can assist in detection of the presence of significant CHL, assess the patency of PETs, and provide frequency-specific information in the audiometric range.

Evaluation of Upper Airway Stimulation for Adolescents With Down Syndrome and Obstructive Sleep Apnea.

Importance: Patients with Down syndrome have a high incidence of persistent obstructive sleep apnea (OSA) and limited treatment options. Upper airway hypoglossal stimulation has been shown to be effective for adults with OSA but has not yet been evaluated for pediatric populations. Objective: To evaluate the safety and effectiveness of upper airway stimulation for adolescent patients with Down syndrome and severe OSA. Design, Setting, and Participants: This prospective single-group multicenter cohort study with 1-year follow-up was conducted between April 1, 2015, and July 31, 2021, among a referred sample of 42 consecutive adolescent patients with Down syndrome and persistent severe OSA after adenotonsillectomy. Intervention: Upper airway stimulation. Main Outcomes and Measures: The prespecified primary outcomes were safety and the change in apnea-hypopnea index (AHI) from baseline to 12 months postoperatively. Polysomnographic and quality of life outcomes were assessed at 1, 2, 6, and 12 months postoperatively. Results: Among the 42 patients (28 male patients [66.7%]; mean [SD] age, 15.1 [3.0] years), there was a mean (SD) decrease in AHI of 12.9 (13.2) events/h (95% CI, -17.0 to -8.7 events/h). With the use of a therapy response definition of a 50% decrease in AHI, the 12-month response rate was 65.9% (27 of 41), and 73.2% of patients (30 of 41) had a 12-month AHI of less than 10 events/h. The most common complication was temporary tongue or oral discomfort, which occurred in 5 patients (11.9%). The reoperation rate was 4.8% (n = 2). The mean (SD) improvement in the OSA-18 total score was 34.8 (20.3) (95% CI, -42.1 to -27.5), and the mean (SD) improvement in the Epworth Sleepiness Scale score was 5.1 (6.9) (95% CI, -7.4 to -2.8). The mean (SD) duration of nightly therapy was 9.0 (1.8) hours, with 40 patients (95.2%) using the device at least 4 hours a night. Conclusions and Relevance: Upper airway stimulation was able to be safely performed for 42 adolescents who had Down syndrome and persistent severe OSA after adenotonsillectomy with positive airway pressure intolerance. There was an acceptable adverse event profile with high rates of therapy response and quality of life improvement. Trial Registration: ClinicalTrials.gov Identifier: NCT02344108.

Demographic and Clinical Characteristics Associated With Adherence to Guideline-Based Polysomnography in Children With Down Syndrome.

OBJECTIVES: To compare the demographic and clinical characteristics of children with Down syndrome who did and did not receive polysomnography to evaluate for obstructive sleep apnea after publication of the American Academy of Pediatrics' guidelines recommending universal screening by age 4 years. STUDY DESIGN: Retrospective cohort study. SETTING: Single tertiary pediatric hospital. METHODS: Review was conducted of children with Down syndrome born between 2007 and 2012. Children who obtained polysomnography were compared with children who did not, regarding demographic data, socioeconomic status, and comorbidities. RESULTS: We included 460 children with Down syndrome; 273 (59.3%) received at least 1 polysomnogram, with a median age of 3.6 years (range, 0.1-8.9 years). There was no difference in the distribution of sex, insurance status, or socioeconomic status between children who received polysomnography and those who did not. There was a significant difference in race distribution (P = .0004) and distance from home to the medical center (P < .0001) between groups. Among multiple medical comorbidities, only children with a history of hypothyroidism (P = .003) or pulmonary aspiration (P = .01) were significantly more likely to have obtained polysomnography. CONCLUSIONS: Overall, 60% of children with Down syndrome obtained a polysomnogram. There was no difference between groups by payer status or socioeconomic status. A significant difference in race distribution was noted. Proximity to the medical center and increased medical need appear to be associated with increased likelihood of obtaining a polysomnogram. This study illustrates the need for improvement initiatives to increase the proportion of patients receiving guideline-based screening.

Sleep Architecture in Children With Down Syndrome With and Without Obstructive Sleep Apnea.

OBJECTIVE: To characterize polysomnographic sleep architecture in children with Down syndrome and compare findings in those with and without obstructive sleep apnea. STUDY DESIGN: Case series with retrospective review. SETTING: Single tertiary pediatric hospital (2005-2018). METHODS: We reviewed the electronic health records of patients undergoing polysomnography who were referred from a specialized center for children with Down syndrome (age, ≥12 months). Continuous positive airway pressure titration, oxygen titration, and split-night studies were excluded. RESULTS: A total of 397 children were included (52.4% male, 81.6% Caucasian). Mean age at the time of polysomnography was 4.7 years (range, 1.4-14.7); 79.4% had obstructive sleep apnea. Sleep variables were reported as mean (SD) values: sleep efficiency, 85% (11%); sleep latency, 29.8 minutes (35.6); total sleep time, 426 minutes (74.6); rapid eye movement (REM) latency, 126.8 minutes (66.3); time spent in REM sleep, 22% (7%); arousal index, 13.3 (5); and time spent supine, 44% (28%). There were no significant differences between those with obstructive sleep apnea and those without. Sleep efficiency <80% was seen in 32.5%; 34.3% had a sleep latency >30 minutes; 15.9% had total sleep time <360 minutes; and 75.6% had an arousal index >10/h. Overall, 69.2% had ≥2 metrics of poor sleep architecture. REM sleep time <20% was seen in 35.3%. REM sleep time decreased with age. CONCLUSION: In children with Down syndrome, 32.5% had sleep efficiency <80%; 75.6% had an elevated arousal index; and 15.9% had total sleep time <360 minutes. More than a third of the patients had ≥3 markers of poor sleep architecture. There was no difference in children with or without obstructive sleep apnea.

Redefining Success by Focusing on Failures After Pediatric Hypoglossal Stimulation in Down Syndrome.

OBJECTIVES/HYPOTHESIS: Patients with Down syndrome have a high incidence of obstructive sleep apnea (OSA) and limited treatment options. Hypoglossal stimulation has shown efficacy but has not yet been approved for pediatric populations. Our objective is to characterize the therapy response of adolescent patients with down syndrome and severe OSA who underwent hypoglossal stimulation. STUDY DESIGN: Prospective longitudinal trial. METHODS: We are conducting a multicenter single-arm trial of hypoglossal stimulation for adolescent patients with Down syndrome and severe OSA. Interim analysis was performed to compare objective sleep and quality of life outcomes at 12 months postoperatively for the first 20 patients. RESULTS: The mean age was 15.5 and baseline AHI 24.2. Of the 20 patients, two patients (10.0%) had an AHI under 1.5 at 12 months; nine patients of 20 (45.0%) under five; and 15 patients of 20 (75.0%) under 10. The mean decrease in AHI was 15.1 (P < .001). Patients with postoperative AHI over five had an average baseline OSA-18 survey score of 3.5 with an average improvement of 1.7 (P = .002); in addition, six of these patients had a relative decrease of apneas compared to hypopneas and seven had an improvement in percentage of time with oxygen saturation below 90%. CONCLUSIONS: Patients with persistently elevated AHI 12 months after hypoglossal implantation experienced improvement in polysomnographic and quality of life outcomes. These results suggest the need for a closer look at physiologic markers for success beyond reporting AHI as the gold standard. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:1663-1669, 2021.

Findings on MR sleep studies as biomarkers to predict outcome of genioglossus advancement in the treatment of obstructive sleep apnea in children and young adults.

OBJECTIVE: Genioglossus advancement, an operation to pull the tongue anteriorly, is a treatment of obstructive sleep apnea (OSA) secondary to glossoptosis. MRI predictors to identify which children will benefit from genioglossus advancement would be helpful for planning. We reviewed imaging findings on MR sleep studies as biomarkers to predict success or failure of genioglossus advancement in the treatment of OSA in children and young adults. MATERIALS AND METHODS: Twenty-eight patients who had undergone genioglossus advancement and preoperative MRI were identified. For each subject, genioglossus advancement, which was performed to treat OSA, was categorized as a success or failure on the basis of polysomnography and clinical criteria. Static and dynamic cine MR sequences were retrospectively evaluated for multiple parameters including measurements of the size of the tongue and of the bony confines of the supraglottic airway, the ratio of tongue size to bony confines size, static size and dynamic changes of the retroglossal airway, tonsil size, and soft palate thickness. Radiologists were blinded to the outcome of genioglossus advancement (i.e., success or failure category). Numeric biomarkers were compared in an analysis-of-covariance model adjusting for patient age. RESULTS: Genioglossus advancement was successful for the treatment of OSA in 17 patients and failed in 11 patients. The relative size of the tongue (tongue-bony confines ratio) was larger in patients with a successful surgical outcome than in those for whom the procedure failed (mean ratio, 0.51 vs 0.46; p = 0.023). Smaller adenoids were associated with a successful outcome (mean size of adenoids, 9.1 vs 12.4 mm; p = 0.049). No other biomarker-including absolute tongue size and airway size or dynamic airway motion-was significant. CONCLUSION: The relative (not absolute) tongue size and small size of the adenoid tonsils on MRI were predictors of success of genioglossus advancement for the treatment of glossoptosis causing OSA. These findings may be helpful in guiding surgical decision making in children with OSA.

Subcutaneous emphysema with pneumomediastinum after tonsillectomy: Case report and review of the literature.

Subcutaneous emphysema is a rare complication of tonsillectomy.We report a case of post-tonsillectomy crepitus with radiographic extravasation of contrast from the tonsil fossa into the neck, subcutaneous emphysema, pneumomediastinum and small pneumothorax in a patient with Down Syndrome. Subsequent direct laryngoscopy showed no visible defect in the mucosal or muscle layers of the tonsil fossa. We explore common presenting symptoms, clinical course, and treatment of subcutaneous emphysema secondary to tonsillectomy.

Endoscopic Removal of a Cervical Esophageal Duplication Cyst.

A 6-month-old female presented for 2 months of noisy breathing. Flexible laryngoscopy showed limited bilateral vocal fold abduction. Computed tomography revealed a non-enhancing 3.6 × 2.3 × 3.5 cystic prevertebral mass spanning C2-T. Using an endoscopic approach, the overlying mucosa was incised, and the cyst was freed and fully excised from the surrounding mucosa with blunt microlaryngeal instruments without complication. Three months postoperatively she had no respiratory issues and was eating well. Flexible laryngoscopy revealed bilateral vocal fold mobility. We propose that endoscopic removal of a cervical esophageal duplication cyst in selected cases is an alternative to open excision. Laryngoscope, 130:2053-2055, 2020.

Update on hypoglossal nerve stimulation in children with down syndrome and obstructive sleep apnea.

OBJECTIVES/HYPOTHESIS: Hypoglossal nerve (HGN) stimulation is a novel therapy for obstructive sleep apnea (OSA) in adults. Its efficacy and safety in children with Down syndrome (DS) was previously reported in a preliminary case series of six adolescents. STUDY DESIGN: Case series. METHODS: Twenty nonobese children and adolescents (aged 10-21 years) with DS and severe OSA (apnea-hypopnea index [AHI] >10 and <50 events/hr) despite prior adenotonsillectomy were enrolled. Participants had failed a trial of continuous positive airway pressure therapy and underwent sleep endoscopy confirming surgical candidacy. The primary outcome was to assess safety and monitor for adverse events. Secondary outcomes included efficacy in reducing AHI (% reduction in AHI), adherence to therapy, and change in a validated quality-of-life instrument, the OSA-18 survey. RESULTS: All 20 children (median age = 16.0 years [interquartile range = 13-17 years], 13 male) were implanted with no long-term complications. We report two interval adverse events, both of which were corrected with revision surgery. Twenty participants completed the 2-month polysomnogram, with median percent reduction in titration AHI of 85% (interquartile range = 75%-92%). The median nightly usage for these children was 9.21 hours/night. There was a median change in the OSA-18 score of 1.15, indicating a moderate, yet significant, clinical change. CONCLUSIONS: HGN stimulation was safe and effective in the study population. Two minor surgical complications were corrected surgically. Overall, these data suggest that pediatric HGN stimulation appears to be a safe and effective therapy for children with DS and refractory severe OSA. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:E263-E267, 2020.

Adherence to Guidelines for Screening Polysomnography in Children with Down Syndrome.

OBJECTIVES: To compare the percentage and mean age of children with Down syndrome (DS) who underwent polysomnography (PSG) to evaluate for obstructive sleep apnea (OSA) before and after the introduction of the American Academy of Pediatrics guidelines recommending universal screening by age 4 years. STUDY DESIGN: Retrospective cohort study. SETTING: Single tertiary pediatric hospital. METHODS: This study is a review of patients with DS seen in a subspecialty clinic. Children born preguidelines (2000-2006) were compared with children born postguidelines (2007-2012) regarding percentage receiving PSG, age at first PSG, and rate of OSA. RESULTS: We included 766 children with DS; 306 (40%) were born preguidelines. Overall, 61% (n = 467) underwent PSG, with a mean ± SD age of 4.2 ± 2.9 years at first PSG; 341 (44.5%) underwent first PSG by age 4 years. The rate of OSA (obstructive index ≥1 event/hour) among children undergoing first PSG was 78.2%. No difference was seen in the percentage receiving PSG preguidelines (63.4%) versus postguidelines (59.4%, P = .26). The mean age at the time of first PSG was 5.3 ± 3.5 years preguidelines versus 3.4 ± 2.0 years postguidelines (P < .0001). Children in the postguidelines cohort were more likely to undergo first PSG during the ages of 1 through 4 years (67.4% vs 52.1%, P < .0001). There was no difference in rates of OSA between the pre- and postguidelines cohorts (79.8% vs 75.9%, P = .32). CONCLUSIONS: Nearly two-thirds of children with DS (61%) underwent PSG overall, with a significant shift toward completion of PSG at an earlier age after the introduction of the American Academy of Pediatrics guidelines for universal screening for OSA.

The frequency of lingual tonsil enlargement in obese children.

OBJECTIVE: Enlargement of the lingual tonsils is being increasingly recognized as a not uncommon and treatable cause of obstructive sleep apnea, particularly in patients with Down syndrome who have undergone palatine tonsillectomy and adenoidectomy. We have recognized an increasing number of patients who are obese and have obstructive sleep apnea with enlarged lingual tonsils. The purpose of this study was to evaluate the frequency of enlarged lingual tonsils in obese children. SUBJECTS AND METHODS: Seventy-one obese children (mean body mass index = 41.6 kg/m(2)) underwent sagittal fast spin-echo inversion recovery imaging. Lingual tonsils were identified and measured in the greatest anteroposterior diameter. Lingual tonsils > 10 mm were considered markedly enlarged. The subgroup with absent palatine tonsils (previous tonsillectomy) (n = 41) were compared with those with palatine tonsils present (n = 30). RESULTS: Forty-four (62%) of the obese children had measurable lingual tonsils, which is greater than the frequency previously reported in normal subjects (0%), subjects with obstructive sleep apnea (33%), or subjects with Down syndrome and obstructive sleep apnea (50%). Ten (14%) had lingual tonsils > 10 mm. Obese subjects with absent palatine tonsils (previous tonsillectomy) had a higher prevalence of measurable lingual tonsils than those with palatine tonsils (78% vs 22%, respectively; p < 0.001) and a higher prevalence of lingual tonsils > 10 mm (90% vs 10%, p < 0.001). CONCLUSION: Obese children have a high frequency of enlargement of the lingual tonsils with a significantly higher prevalence in those with previous tonsillectomy. Enlarged lingual tonsils may play a role in the pathogenesis of obstructive sleep apnea in obese children.

Outcomes of Drug-Induced Sleep Endoscopy-Directed Surgery for Pediatric Obstructive Sleep Apnea.

Objectives To determine the effectiveness of pediatric drug-induced sleep endoscopy (DISE)-directed surgery for children with infant obstructive sleep apnea (OSA) or OSA after adenotonsillectomy. Study Design Case series with chart review. Setting Tertiary care pediatric hospital. Subjects and Methods We included 56 children undergoing DISE from October 2013 to September 2015 who underwent subsequent surgery to address OSA. The primary outcome was successful response to DISE-directed surgery based on the postoperative obstructive Apnea-Hypopnea Index (oAHI). Wilcoxon matched-pairs signed-ranks tests were used to compare polysomnography variables before and after surgery, and regression was used to model response to surgery. Results We evaluated 56 patients with a mean age of 5.9 ± 5.5 years (range, 0.1-17.4) and mean body mass index of 21.2 ± 7.9 kg/m2 (percentile, 77 ± 30). The most commonly performed surgical procedures were adenoidectomy (48%, n = 27), supraglottoplasty (38%, n = 21), tonsillectomy (27%, n = 15), lingual tonsillectomy (13%, n = 7), nasal surgery (11%, n = 6), pharyngoplasty (7%, n = 4), and partial midline glossectomy (7%, n = 4). Mean oAHI improved from 14.9 ± 13.5 to 10.3 ± 16.2 events/hour, with 54% (30 of 56) of children with oAHI <5 and 16.1% (9 of 56) with oAHI <1. There was a significant improvement in oAHI ( P = .001) and saturation nadir ( P < .001) but not in time with end tidal carbon dioxide >50 mm Hg ( P = .14). Multivariable modeling, controlling for age, race, body mass index, sex, and baseline polysomnography variables, revealed that white race predicted success of DISE-directed surgery. Conclusion Fifty-four percent of children with infant OSA or persistent OSA after adenotonsillectomy had oAHI <5 events per hour after DISE-directed surgery. Only white race was predictive of oAHI <5 events per hour.

OSAS in Down syndrome: T&A versus T&A plus lateral pharyngoplasty.

OBJECTIVE: Obstructive Sleep Apnea Syndrome (OSAS) is common in children with Down syndrome (DS). Adenotonsillectomy (T&A) has traditionally been the initial surgical treatment. More aggressive surgery has also been recommended. Previous studies have used parental reporting and not objective data to assess treatment outcomes. Polysomnography (PSG) is used to objectively evaluate the results of T&A versus T&A plus lateral pharyngoplasty in the initial treatment of OSAS in children with DS. METHODS: This is a retrospective study of children with OSAS and DS. Group 1 consisted of 21 children with DS who underwent T&A. Group 2 consisted of 16 children of similar age who had T&A plus lateral pharyngoplasty as initial surgical treatment. Post-operative PSG's were available for all patients. Apnea/hypopnea index (AHI), presence of hypoxemia and hypercarbia, and arousal index were measured and compared. RESULTS: In group 1, after T&A, 48% continued to have an elevated AHI. If hypercarbia and hypoxemia are included in the result analysis, 67% continued to have abnormal PSG's after their surgery. In group 2, 63% had an elevated AHI post-operatively. When hypercarbia and hypoxemia are included in the analysis, 75% continued to have abnormal PSG's after surgery. There was no statistically significant difference in the outcome of the two groups. CONCLUSIONS: Pediatric patients with OSAS and DS may show improvement after T&A, however only about one third will have a normal post-operative sleep study. Adding a lateral pharyngoplasty does not improve these results. Further study with objective outcome data is needed to determine a better first line surgical treatment for these patients.

Polysomnography in Pediatric Otolaryngology: If Not Obstructive Sleep Apnea, What Is It?

Objective To determine common polysomnographic (PSG) diagnoses for children referred by otolaryngologists. Study Design Retrospective case series with chart review. Setting Single tertiary pediatric hospital (2010-2015). Subjects and Methods Review of the medical records of 1258 patients undergoing PSG by otolaryngology referral. Patients who underwent previous otolaryngologic surgery were excluded. Data distributions were evaluated using means with standard deviations for continuous variables and frequencies with percentages for categorical variables. Results A total of 1258 patients were included; 55.9% were male, 64.5% were Caucasian, 16.6% had Down syndrome, and 48% had public insurance. The median age at the time of PSG was 5.2 years (range = 0.2-18.94). Indications for PSG were sleep-disordered breathing (SDB; 69.4%), restless sleep (12.7%), airway anomalies (7.5%), and laryngomalacia (7.2%). SDB was seen in 73.4%, obstructive sleep apnea (OSA) in 53.2%, OSA + central sleep apnea (CSA) in 4.5%, CSA in 0.9%, and non-OSA snoring in 15%. Other diagnoses included periodic limb movements of sleep (PLMS; 7.4%), hypoventilation (6.8%), and nonapneic hypoxemia (2.6%). SDB was more common in younger children and seen in 91.4% of children <12 months and in 69.2% of children ≥24 months, while non-OSA snoring was more common with increasing age (3.7% in children <12 months, 17.7% of children ≥24 months). PLMS were seen in 8.9% of children ≥24 months and in no children <12 months. Conclusion While OSA and snoring were the most common diagnoses reported, PLMS, alveolar hypoventilation, and CSA occurred in 7.4%, 6.8%, and 5.4%, respectively. These findings indicate that additional diagnoses other than OSA should be considered for children seen in an otolaryngology clinic setting who undergo PSG for sleep disturbances.

Polysomnographic outcomes following lingual tonsillectomy for persistent obstructive sleep apnea in down syndrome.

OBJECTIVES/HYPOTHESIS: Lingual tonsil hypertrophy is a common cause of persistent airway obstruction in patients with Down syndrome (DS) following adenotonsillectomy (T&A); however, little is known about the effect of lingual tonsillectomy (LT) on polysomnographic outcomes in these patients. Our objective was to describe changes in sleep-related respiratory outcomes following LT in children with DS and persistent obstructive sleep apnea (OSA) following T&A. STUDY DESIGN: Retrospective case series. METHODS: We included all children with DS who underwent polysomnography before and after LT at a tertiary care center from 2003 to 2013. Nonparametric analysis of variables was performed. RESULTS: Forty patients with DS underwent LT; 21 met inclusion criteria. The mean age at surgery was 9.3 ± 4.3 years and 47.6% were female. The median apnea-hypopnea index (AHI) was 9.1 events/hour (range, 3.8 to 43.8 events/hour) before surgery and 3.7 events/hour (range, 0.5 to 24.4 events/hour) after surgery. The median improvement in overall AHI and the obstructive AHI (oAHI) were 5.1 events/hour (range, -2.9 to 41) and 5.3 events/hour (range, -2.9 to 41), respectively (P <.0001). The mean oxygen saturation nadir improved from 84% to 89% (P =.004). The mean time with CO2 > 50 mm Hg, central index, and percentage of rapid eye movement sleep were not significantly different. After surgery, the oAHI was <5 events/hour in 61.9% and ≤1 in 19% of patients. CONCLUSIONS: In children with DS, persistent OSA after T&A and lingual tonsil hypertrophy, LT significantly improved AHI, oAHI, and O2 saturation nadir. We recommend that children with DS should be evaluated for lingual tonsil hypertrophy if found to have persistent OSA following T&A. LEVEL OF EVIDENCE: 4 Laryngoscope, 2016 127:520-524, 2017.

Effect of airflow and material models on tissue displacement for surgical planning of pharyngeal airways in pediatric down syndrome patients.

Pharyngeal narrowing in obstructive sleep apnea (OSA) results from flow-induced displacement of soft tissue. The objective of this study is to evaluate the effect of airflow parameters and material model on soft tissue displacement for planning surgical treatment in pediatric patients with OSA and Down syndrome (DS). Anatomically accurate, three-dimensional geometries of the pharynx and supporting tissue were reconstructed for one pediatric OSA patient with DS using magnetic resonance images. Six millimeters of adenoid tissue was virtually removed based on recommendations from the surgeon, to replicate the actual adenoidectomy. Computational simulations of flow-induced obstruction of the pharynx during inspiration were performed using patient-specific values of tissue elasticity for pre and post-operative airways. Sensitivity of tissue displacement to selection of turbulence model, variation in inspiratory airflow, nasal airway resistance and choice of non-linear material model was evaluated. The displacement was less sensitive to selection of turbulence model (10% difference) and more sensitive to airflow rate (20% difference) and nasal resistance (30% difference). The sensitivity analysis indicated that selection of Neo-Hookean, Yeoh, Mooney-Rivlin or Gent models would result in identical tissue displacements (less than 1% difference) for the same flow conditions. Change in pharyngeal airway resistance between the rigid and collapsible models was nearly twice for the pre-operative case as compared to the post-operative scenario. The tissue strain at the site of obstruction in the velopharyngeal airway was lowered by approximately 84% following surgery. Inclusion of tissue elasticity resulted in better agreement with the actual surgical outcome compared to a rigid wall assumption, thereby emphasizing the importance of pharyngeal compliance for guiding treatment in pediatric OSA patients.

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.

Temporal trends in inpatient pediatric sleep apnea surgery: 1993-2010.

OBJECTIVES/HYPOTHESIS: We sought to characterize changes in the patterns of inpatient surgical sleep care over time and ascertain if these changes were consistent with previously reported trends in adult surgical sleep care. STUDY DESIGN: Repeated cross-sectional study. METHODS: Discharge data from the U.S. Nationwide Inpatient Sample for 125,691 nasal, palatal, or hypopharyngeal procedures in children for sleep-disordered breathing or obstructive sleep apnea (OSA) from 1993 to 2010 were analyzed using cross-tabulations and multivariate regression modeling. RESULTS: Inpatient surgical sleep procedures increased from 45,671 performed in 1993 to 2000 (study period 1) to 80,020 in 2001 to 2010 (study period 2). Overall, patients were commonly male (61.3%), privately insured (46.8%), 2 to 6 years old (39.4%), and white (36.4%). Obesity was reported in 4.6% and 6.7% of children during study periods 1 and 2, respectively (P < .0001). Tonsillectomy (with and without adenoidectomy) was the most commonly performed procedure in both study periods. With the exception of uvulopalatopharyngoplasty and tracheostomy, all sleep procedures increased over time; however, multilevel surgery did not significantly increase (P = .28). Children who underwent sleep surgery during study period 2 were more likely to receive a supraglottoplasty (P = .0125) and to undergo procedures at high-volume hospitals (P = .0311), and less likely to undergo a tracheostomy (P < .0001). CONCLUSIONS: These data reflect changing trends in the surgical management of pediatric OSA, with significant increases in nasal and hypopharyngeal procedures, particularly lingual tonsillectomy and supraglottoplasty. Unlike the trend in adults, multilevel surgery in children with sleep disordered breathing or OSA has not yet been integrated into routine clinical practice. LEVEL OF EVIDENCE: 2C Laryngoscope, 127:1235-1241, 2017.