Associations between Adenotonsillar Hypertrophy, Age, and Obesity in Children with Obstructive Sleep Apnea

To investigate the contributions of adenoid and tonsil size to childhood obstructive sleep apnea (OSA) and the interactions between adenotonsillar hypertrophy, age, and obesity in children with OSA.  In total, 495 symptomatic patients were recruited. The patients were assigned to four groups according to age：toddler (age 1-3, n=42), preschool (age 3-6, n=164), school (age 6-12, n=200), and adolescence (age 12-18, n=89). All subjects had tonsil size graded by otolaryngologists, adenoid size determined on lateral radiographs (Fujioka method), and a full-night polysomnography. The apnea-hypopnea index (AHI), adenoid size, and tonsil size were compared in obese and non-obese children in the four age groups. Adjusted odds ratios (ORs) and 95% confidence interval (CI) of adenotonsillar hypertrophy and OSA risk were estimated by multi-logistic regression.  The AHI was positively related to tonsil grade (r=0.33, p <0.001) and adenoid size (r=0.24, p <0.01) in all patients. Tonsil grade was positively related to AHI in all four age groups. Adenoid size was positively related to AHI in the toddler, preschool, school groups, but not in the adolescent group (r=0.11, p=0.37). Tonsil grade and adenoid size were both positively related to AHI in obese and non-obese children. In the regression model, obesity (OR=2.89; 95% CI 1.47-5.68), tonsillar hypertrophy (OR=3.15; 95% CI 2.04-4.88), and adenoidal hypertrophy (OR=1.89; 95% CI 1.19-3.00) significantly increased OSA risk.  Adenotonsillar hypertrophy and obesity are the major determinants of OSA in children. However, the influence of adenoid size decreases in adolescence.

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title: Diagnosis and Management of Childhood Obstructive Sleep Apnea Syndrome
abstract: This revised clinical practice guideline, intended for use by primary care clinicians, provides recommendations for the diagnosis and management of the obstructive sleep apnea syndrome (OSAS) in children and adolescents. This practice guideline focuses on uncomplicated childhood OSAS, that is, OSAS associated with adenotonsillar hypertrophy and/or obesity in an otherwise healthy child who is being treated in the primary care setting.  Of 3166 articles from 1999–2010, 350 provided relevant data. Most articles were level II–IV. The resulting evidence report was used to formulate recommendations.  The following recommendations are made. (1) All children/adolescents should be screened for snoring. (2) Polysomnography should be performed in children/adolescents with snoring and symptoms/signs of OSAS; if polysomnography is not available, then alternative diagnostic tests or referral to a specialist for more extensive evaluation may be considered. (3) Adenotonsillectomy is recommended as the first-line treatment of patients with adenotonsillar hypertrophy. (4) High-risk patients should be monitored as inpatients postoperatively. (5) Patients should be reevaluated postoperatively to determine whether further treatment is required. Objective testing should be performed in patients who are high risk or have persistent symptoms/signs of OSAS after therapy. (6) Continuous positive airway pressure is recommended as treatment if adenotonsillectomy is not performed or if OSAS persists postoperatively. (7) Weight loss is recommended in addition to other therapy in patients who are overweight or obese. (8) Intranasal corticosteroids are an option for children with mild OSAS in whom adenotonsillectomy is contraindicated or for mild postoperative OSAS.

title: Snoring, apneic episodes, and nocturnal hypoxemia among children 6 months to 6 years old. An epidemiologic study of lower limit of prevalence.
abstract: To identify a lower limit of the prevalence of sleep-related breathing disturbances among preschool children.



A cross-sectional epidemiologic study in two stages, first by questionnaires and second by whole-night investigation of children symptomatic of the sleep apnea syndrome.



Gardabaer, a small town, 10 km south of Reykjavìk, Iceland.



All children in Gardabaer, 6 months to 6 years old (n = 555).



Symptom score estimated by questionnaire and respiratory events based on overnight oximetry, thermistors, and a static charge sensitive bed.



The response rate was 81.8%. Snoring was reported as often or very often among 14 (3.2%) and occasionally by 73 (16.7%). Apneic episodes were reported often or very often among seven (1.6%). Altogether 18 children were highly suspected of the sleep apnea syndrome because of habitual snoring or apneic episodes. The girls (n = 9) were older than the boys (mean age: 46 +/- 21 months vs 20 +/- 12 months, p < 0.001). Eventually 11 children came for a whole-night investigation and 8 of them showed more than three respiratory events per hour of sleep, associated with > or = 4% oxygen desaturation. The lower limit of the sleep apnea syndrome prevalence among these children was thus 2.9% (SE, 0.5%).



Among children, symptoms such as snoring and apneic episodes are reported relatively seldom, but a high proportion of the children with these symptoms have hypoxic respiratory events.

title: Ambulatory blood pressure in children with obstructive sleep apnoea: a community based study
abstract: Childhood obstructive sleep apnoea (OSA) is increasingly being recognised. Its effects on blood pressure (BP) elevation and hypertension are still controversial.  To evaluate the association between OSA and ambulatory BP in children.  Children aged 6–13 years from randomly selected schools were invited to undergo overnight sleep study and ambulatory BP monitoring after completing a validated OSA questionnaire. OSA was diagnosed if the obstructive apnoea–hypopnoea index (AHI) was >1, and normal controls had AHI <1 and snoring <3 nights per week. Children with OSA were subdivided into a mild group (AHI 1–5) and moderate to severe group (AHI >5).  306 subjects had valid sleep and daytime BP data. Children with OSA had significantly higher BP than normal healthy children during both sleep and wakefulness. BP levels increased with the severity of OSA, and children with moderate to severe disease (AHI >5) were at significantly higher risk for nocturnal systolic (OR 3.9 (95% CI 1.4 to 10.5)) and diastolic (OR 3.3 (95% CI 1.4 to 8.1)) hypertension. Multiple linear regression revealed a significant association between oxygen desaturation index and AHI with daytime and nocturnal BP, respectively, independent of obesity.  OSA was associated with elevated daytime and nocturnal BP, and is an independent predictor of nocturnal hypertension. This has important clinical implications as childhood elevated BP predicts future cardiovascular risks. Future studies should examine the effect of therapy for OSA on changes in BP.

title: Neurocognitive and behavioral morbidity in children with sleep disorders
abstract: This review examines in detail progress made regarding our understanding of the presence and pathophysiology of cognitive and behavioral morbidities among children with sleep disorders in general. Particular focus is given to pediatric obstructive sleep apnea.  In recent years, increased awareness of the morbid consequences of respiratory sleep disturbances in children has emerged. Evidence suggesting a causal association of intermittent hypoxia and sleep fragmentation with alterations in memory, attention, and intelligence has accumulated. Research has also identified a link between sleep disorders, and problematic and hyperactive behaviors and mood disturbances. Furthermore, there is considerable inter-individual variability in the presence and magnitude of neurobehavioral morbidity at any given level of disease severity. This further suggests that, in addition to the disease per se, both genetic (individual susceptibility) and environmental modifiers play a role in determining morbidity.  A more individually tailored approach to detecting morbidity associated with sleep disorders in children, employing biomarkers and gene-related single nucleotide polymorphisms, may ultimately be required to allow more rational prioritization of treatment.

title: Obstructive sleep apnea, morbid obesity, and adenotonsillar surgery: a review of the literature.
abstract: Obstructive sleep apnea syndrome is a common occurrence in the obese pediatric population. As this subgroup is rapidly expanding, these children will be increasingly encountered by the otolaryngologist in practice. The literature regarding the etiology, pathogenesis, diagnosis and surgical treatment of obstructive sleep apnea in morbidly obese children is reviewed and pertinent data presented.

title: Updated systematic review of tonsillectomy and adenoidectomy for treatment of pediatric obstructive sleep apnea/hypopnea syndrome
abstract: Perform an updated systematic review and meta-analysis to determine the cure rate of tonsillectomy and adenoidectomy (T&A) for pediatric obstructive sleep apnea/hypopnea syndrome (OSAHS).  A systematic review was performed to identify English-language studies that evaluate the treatment of pediatric (age < 20 years) OSAHS patients with T&A using polysomnography as a metric of cure. Twenty-three studies fit the inclusion criteria and a meta-analysis was performed to determine the overall success. Meta-analysis was also performed to determine the success in obese and comorbid populations vs cohorts of healthy children.  The meta-analysis included 1079 subjects (mean sample size of 42 patients) with a mean age of 6.5 years. The effect measure was the percentage of pediatric patients with OSAHS who were successfully treated (k = 22 studies) with T&A based on preoperative and postoperative PSG data. Random-effects model estimated the treatment success of T&A was 66.3 percent, when cure was defined per each individual study. When “cure” was defined as an apnea-hypopnea index (AHI) of <1 (k = 9 studies), random-effects model estimate for OSAHS treatment success with T&A was 59.8 percent. Postoperative mean AHI was significantly decreased from preoperative levels.  Contrary to popular belief, meta-analysis of current literature demonstrates that pediatric sleep apnea is often not cured by T&A. Although complete resolution is not achieved in most cases, T&A still offers significant improvements in AHI, making it a valuable first-line treatment for pediatric OSAHS.

title: Systematic Review of Pediatric Tonsil Size and Polysomnogram-Measured Obstructive Sleep Apnea Severity
abstract: Systematically review the biomedical literature for data comparing clinical, subjective tonsil size (0-4+ scale) to objectively measured obstructive sleep apnea syndrome (OSAS) using polysomnography (PSG).  PubMed database.  A comprehensive PubMed MeSH search was conducted to identify articles comparing subjective tonsil size to objectively measured OSAS. Inclusion criteria included pediatric patients only, sample size greater than 5, and sufficient data to extract for analysis. Exclusion criteria included patients with obesity or craniofacial syndromes.  Twenty articles were included in the final data set. The mean sample size was 161 (range, 32-700) and grand mean age was 6.7 (range, 2.7-11.7). Case series (evidence based medicine [EBM] level 4) was the predominant study design (16 studies). Eleven of 20 studies concluded there was an association between subjective tonsil size and objective OSAS, whereas 9 did not. Varying statistical techniques were used including simple diagnostic tables (k = 8), linear or logistic regression (k = 19), correlation (k = 5), and analysis of variance (k = 2). A customized quality assessment of each study was performed. Studies showing no association between tonsil size and OSAS had a higher quality score than studies showing an association (3.22 vs 2.36, P = .0317).  The association between subjective pediatric tonsil size using 0-4+ scale and objective OSAS severity is weak at best. High-quality studies suggest no association. Providers must recognize the limitations of using tonsil size in clinical decision making.

title: Assessment of lateral cephalometric diagnosis of adenoid hypertrophy and posterior upper airway obstruction: a systematic review.
abstract: Our objective was to evaluate the capability of lateral cephalograms in diagnosing hypertrophied adenoids and obstructed posterior nasopharyngeal airways.



A systematic review of the literature by using several electronic databases (Cochrane Library, Medline, Medline in progress, PubMed, Web of Science, Embase, and Lilacs) was performed with the help of a senior health-sciences librarian. The electronic search was followed up with hand searches. After applying our inclusion-exclusion criteria, the search yielded 11 articles that were then scored based on their methodological validity.



Lateral cephalograms performed reasonably well in evaluating adenoid size; both quantitative measures of adenoid area and subjective grading of adenoid size on lateral cephalograms had reasonable correlations to actual adenoid size (range of r, 0.60 to 0.88). However, evidence suggested that cephalograms were less ideal for evaluating the size of the posterior nasopharyngeal airway. The diagnostic difference is likely because the adenoid is a simpler 3-dimensional structure than the nasopharynx; therefore, it loses less information when compressed into 2 dimensions by the radiograph.



Being used as a screening tool to determine the need for more rigorous ENT follow-up appears to be the greatest utility of lateral cephalograms. Because no consensus could be reached on what are the most useful landmarks, we recommend that clinicians look for multiple deviant measures of adenoid size rather than one definitive quantification.

title: Lateral X-ray view of the skull for the diagnosis of adenoid hypertrophy: a systematic review.
abstract: Many studies have been developed aiming to reveal the usefulness of cavum X-rays and telerradiographies as diagnostic tools for the detection of upper airway obstruction due to adenoid hypertrophy. However, the scientific literature is diverse and controversial. Therefore, a systematic review is proposed; with the objective to determine the diagnosis value of lateral X-ray view of the skull regarding adenoid hypertrophy.



Searching was conducted on Pubmed, Lilacs, Cochrane Library, Embase, and Web of Knowledge databases; and was restricted to studies published in English, Portuguese or Spanish languages, carried out on humans under 18 years of age. All the obtained publications were first submitted to a pre-selection, and then, full-texts (n=66) were analyzed and selected by independent examiners. The resultant studies (n=11) were systematically and critically analyzed, and qualified according to QUADAS (Quality Assessment of Diagnostic Accuracy Studies) questionnaire, an assessment tool designed to qualify diagnostic tests accuracy studies.



Searching and selection procedures generated 11 studies which were considered adequate to be systematically analyzed. Accordingly, large variation was observed concerning the evaluation methods of radiographic and fibronasoendoscopic exams, and the sample characteristics. Additionally, little amount of scientific evidences could be provided, since few radiographic variables were analyzed simultaneously. Moreover, assessment methods were, at most, subjective or poorly described. QUADAS application revealed other significant limitations related to the sampling, such as inadequate spectrum of the investigated "disease" (adenoid hypertrophy), and poor report of the subjects' enrollment and participation process. Further, QUADAS revealed inadequacies regarding methodological features, including poor description of the radiographic exams and assessment methods. In addition, it was also shown that most of the studies did not specify the moment in clinical time when both exams were performed; neither reported a strategy of "blindness" by the examiners.



Despite such limitations, the majority of the resultant data indicates that lateral X-rays might be considered somewhat useful, even though it could not be clearly demonstrated. Future research should then adhere to greater methodological rigor, in order to investigate the significance of radiographies as a screening test.

title: Influence of Gender and Age on Upper-Airway Length During Development
abstract: Obstructive sleep apnea has a strong male predominance in adults but not in children. The collapsible portion of the upper airway is longer in adult men than in women (a property that may increase vulnerability to collapse during sleep). We sought to test the hypothesis that in prepubertal children, pharyngeal airway length is equal between genders, but after puberty boys have a longer upper airway than girls, thus potentially contributing to this change in apnea propensity.  Sixty-nine healthy boys and girls who had undergone computed tomography scans of their neck for other reasons were selected from the computed tomography archives of Rambam and Carmel hospitals. The airway length was measured in the midsagittal plane and defined as the length between the lower part of the posterior hard palate and the upper limit of the hyoid bone. Airway length and normalized airway length/body height were compared between the genders in prepubertal (4- to 10-year-old) and postpubertal (14- to 19-year-old) children.  In prepubertal children, airway length was similar between boys and girls (43.2 ± 5.9 vs 46.8 ± 7.7 mm, respectively). When normalized to body height, airway length/body height was significantly shorter in prepubertal boys than in girls (0.35 ± 0.03 vs 0.38 ± 0.04 mm/cm). In contrast, postpubertal boys had longer upper airways (66.5 ± 9.2 vs 52.2 ± 7.0 mm) and normalized airway length/body height (0.38 ± 0.05 vs 0.33 ± 0.05 mm/cm) than girls.  Although boys have equal or shorter airway length compared with girls among prepubertal children, after puberty, airway length and airway length normalized for body height are significantly greater in boys than in girls. These data suggest that important anatomic changes at puberty occur in a gender-specific manner, which may be important in explaining the male predisposition to pharyngeal collapse in adults.

title: A controlled study of sleep related disordered breathing in obese children
abstract: Unlike the adult sleep related disordered breathing (SDB) patients who are typically obese, the relation between obesity and childhood SDB is not clear.  To investigate whether obese children are more at risk of obstructive SDB when compared to normal population, and whether this risk is potentiated by the presence of pharyngeal lymphoid tissue.  Forty six obese children (age 10.8 (SD 2.3) years; BMI 27.4 (SD 5.1)), and 44 sex and age matched normal weight children (age 11.7 (SD 2.1) years; BMI 18 (SD 1.8)) were studied. All children underwent a set of physical examinations (including the upper airways) and sleep studies.  The obese children were different from the normal weight children in terms of type (predominantly obstructive), frequency, and severity of respiratory disturbances. Depending on the criteria used, 26% or 32.6% of obese children had SDB; 2.3% of normal controls had OAI ⩾1 and 4.5% had RDI ⩾5. Presence of SDB was related to presence of tonsils (size >2; range 0–4) (OR 12.67, 95% CI 2.14 to 75.17) and BMI (OR 1.20, 95% CI 1.08 to 1.33).  Results suggest that obese children are at increased risk of obstructive SDB; the presence of any pharyngeal lymphoid tissue enlargement in obese children should therefore be aggressively managed.

title: Relationship between adenoid size and severity of obstructive sleep apnea in preschool children.
abstract: To investigate the contributions of adenoid and tonsil sizes to obstructive sleep apnea syndrome (OSAS) in normal-weight children in two age categories: preschool and schoolchildren.



Fifty-eight normal-weight (body mass index z-score<2) symptomatic children with OSAS (apnea-hypopnea index ≥ 2) were evaluated. The patients were divided into two age categories: preschool (age<6; n=33) and schoolchildren (age ≥ 6; n=25). Polysomnographic findings and adenoid and tonsil sizes were compared. The relative contributions of body mass index and adenoid and tonsil sizes were also investigated with a regression analysis.



Adenoid grade and apnea index correlated significantly in preschool children (r=0.45, p<0.01). On regression analysis, adenoid grade was a significant predictor of the apnea index in preschool children. The influence of adenoid hypertrophy decreased from preschool to schoolchildren. Tonsil size had little influence on the apnea index in either group.



Adenoid hypertrophy was a major contributor to OSAS in normal-weight preschool children. The upper airway morphology of younger children with OSAS differed from that of older children with OSAS.

title: Normal polysomnographic respiratory values in children and adolescents.
abstract: Polysomnography is important in the evaluation of children and adolescents with sleep-disordered breathing. Adult criteria for obstructive sleep apnea have been shown to be inapplicable to children. Nevertheless, very little data are available regarding normal respiratory parameters during sleep in healthy children and adolescents. The purpose of the study was to characterize normal polysomnography values in healthy children and adolescents and to establish respiratory reference values for pediatric polysomnography.



Seventy healthy, normal children and adolescents were studied. Age ranged from 1 to 15 years (mean +/- SD, 8.02 +/- 4.57 years). All children underwent overnight polysomnography including EEG, electromyography, electrooculography, ECG, pulse oximetry arterial oxygen saturation (SpO(2)), chest wall and abdomen motion, oral and nasal airflow, and end-tidal PCO(2) (PETCO(2)).



Three children (4%) had a mean of 0.37 obstructive apneas (OAs) per hour of sleep (1 to 5 OAs per child per study), with mean apnea duration of 10.3 +/- 2.1 s. This was not accompanied with oxygen desaturation. Twenty-six children had one to seven central apneas (CAs) per child, resulting in a mean of 0.4 CAs per hour of sleep (median, 0.33; 97.5 percentile, 0.9). Eleven of the 58 events of CA in six children coincided with oxygen desaturation to a minimum of 88% (nadir apnea desaturation range, 88 to 93%). The mean SpO(2) was 97.2 +/- 0.8% with SpO(2) nadir of 94.6 +/- 2.2%. PETCO(2) > 45 mm Hg occurred for 1.6 +/- 3.8% of total sleep time (TST) in 21 of 70 children (30%), with a distribution of 1.3 +/- 3.03% in the range of 46 to 47 mm Hg; < 0.7% were within the range of 48 to 50 mm Hg; and in 0.29 +/- 0.24% of TST, PETCO(2) values were > 50 mm Hg.



Based on these data, the recommended limits for normal values are as follows: OA index, 1; CA index, 0.9; oxygen desaturation, 89%; baseline saturation, 92%; and PETCO(2) > 45 mm Hg for < 10% of TST.

title: Polysomnographic Characteristics in Normal Preschool and Early School-Aged Children
abstract: The objective of this study was to describe overnight polysomnographic measures in normal children aged 3 to 7 years. We conducted a retrospective analysis of normal polysomnographic evaluations from participants in 2 large community-based studies of sleep-disordered breathing among preschoolers and early school-aged children at Kosair Children’s Hospital Sleep Medicine Research Center at the University of Louisville. Participants included 542 healthy children with ages ranging from 3.2 to 8.6 years.  Subjects were excluded from analysis if they had documented snoring during polysomnography, an obstructive apnea-hypopnea index of ≥1.0, or a periodic leg-movement index of ≥5.0. Because the greatest differences in polysomnography occurred between ages 5 and 6 years, analyses were performed for children 3 to 5 years and for ages ≥6. Sleep cyclicity was distinct between age groups, with both showing an initial brief rapid-eye-movement period, which lengthened across the night, but only the older group showing a decrease in cycle length across the night. Average obstructive apnea indices were 0.03 per hour of total sleep time (TST) for 3- to 5-year-old children and 0.05 per hour of TST for ≥6-year-old children, whereas central apnea indices were 0.82 and 0.45 per hour of TST, respectively. Older children spent a greater percentage of sleep time supine, and the apnea-hypopnea index differed according to body position. Twenty percent of all subjects had end tidal carbon dioxide values of >45 mm Hg, and 2.2% had recorded values >50 mm Hg during ≥50% TST. High variance was present on all measures.  Developmental changes occur in several polysomnographic measures among normal children from 3 to 7 years of age, particularly during transition from preschool to early school age. Our findings in a large number of healthy community children comprise the most extensive compilation of normative reference values for laboratory-based pediatric polysomnography to date.

title: Meta-analysis of quantitative sleep parameters from childhood to old age in healthy individuals: developing normative sleep values across the human lifespan.
abstract: The purposes of this study were to identify age-related changes in objectively recorded sleep patterns across the human life span in healthy individuals and to clarify whether sleep latency and percentages of stage 1, stage 2, and rapid eye movement (REM) sleep significantly change with age.



Review of literature of articles published between 1960 and 2003 in peer-reviewed journals and meta-analysis.



65 studies representing 3,577 subjects aged 5 years to 102 years.



The research reports included in this meta-analysis met the following criteria: (1) included nonclinical participants aged 5 years or older; (2) included measures of sleep characteristics by "all night" polysomnography or actigraphy on sleep latency, sleep efficiency, total sleep time, stage 1 sleep, stage 2 sleep, slow-wave sleep, REM sleep, REM latency, or minutes awake after sleep onset; (3) included numeric presentation of the data; and (4) were published between 1960 and 2003 in peer-reviewed journals.



In children and adolescents, total sleep time decreased with age only in studies performed on school days. Percentage of slow-wave sleep was significantly negatively correlated with age. Percentages of stage 2 and REM sleep significantly changed with age. In adults, total sleep time, sleep efficiency, percentage of slow-wave sleep, percentage of REM sleep, and REM latency all significantly decreased with age, while sleep latency, percentage of stage 1 sleep, percentage of stage 2 sleep, and wake after sleep onset significantly increased with age. However, only sleep efficiency continued to significantly decrease after 60 years of age. The magnitudes of the effect sizes noted changed depending on whether or not studied participants were screened for mental disorders, organic diseases, use of drug or alcohol, obstructive sleep apnea syndrome, or other sleep disorders.



In adults, it appeared that sleep latency, percentages of stage 1 and stage 2 significantly increased with age while percentage of REM sleep decreased. However, effect sizes for the different sleep parameters were greatly modified by the quality of subject screening, diminishing or even masking age associations with different sleep parameters. The number of studies that examined the evolution of sleep parameters with age are scant among school-aged children, adolescents, and middle-aged adults. There are also very few studies that examined the effect of race on polysomnographic sleep parameters.

title: Recommendations for Prevention of Childhood Obesity
abstract: The majority of US youth are of healthy weight, but the majority of US adults are overweight or obese. Therefore, a major health challenge for most American children and adolescents is obesity prevention—today, and as they age into adulthood. In this report, we review the most recent evidence regarding many behavioral and practice interventions related to childhood obesity, and we present recommendations to health care providers. Because of the importance, we also suggest approaches that clinicians can use to encourage obesity prevention among children, including specific counseling strategies and practice-based, systems-level interventions. In addition, we suggest how clinicians may interact with and promote local and state policy initiatives designed to prevent obesity in their communities.

title: Radiographic evaluation of adenoidal size in children: adenoidal-nasopharyngeal ratio.
abstract: Adenoidal-nasopharyngeal ratios (AN ratios) obtained by simple linear measurements from lateral skull radiographs are described. The AN ratio reliably expresses adenoidal size and patency of the nasopharyngeal airway. The validity of the ratio as an indicator of adenoidal size was determined by evaluation of measurements of radiographs of 1,398 infants and children and comparison with a subjective visual assessment made by experienced observers in 92 patients. An AN ratio greater than 0.80 was present in 34 of 36 patients (94%) subjectively judged to have enlarged adenoids.

title: A case-control study of obstructive sleep apnea-hypopnea syndrome in obese and nonobese chinese children.
abstract: Obesity is a risk factor for obstructive sleep apnea-hypopnea syndrome (OSAHS) in adults. However, the prevalence of OSAHS in children is not clear, and the relationship between obesity and OSAHS remains controversial.



Obese children were recruited from the endocrinology, respiratory, and ear, nose, and throat clinics. Weight-matched, age-matched, and sex-matched children were recruited as control subjects. Standard questionnaires were administered, and a standardized physical examination was carried out. Lateral neck roentgenography, sleep polysomnography, full blood count, and arterial blood gas analysis were also performed. Children with body mass index z-scores of > 1.96 were considered to be obese. An adenoidal/nasopharygeal ratio of > 0.67 was considered to constitute adenotonsillar hypertrophy (ATH). OSAHS was defined as an apnea-hypopnea index (AHI) score of > 5 or obstructive apnea index (OAI) score of > 1.



Ninety-nine obese children and 99 control subjects were recruited into the study. Obese patients had significantly higher AHI and OAI scores, and lower sleep efficiency and minimum arterial oxygen saturation (MinSao(2)) than control subjects. The prevalence of OSAHS was significantly higher in obese children with or without the ATH groups than their nonobese counterparts (odds ratio, 1.9 vs 108, respectively; 95% confidence interval, 1.21 to 4.7 vs 6.2 to 191, respectively). Obesity, tonsillar hypertrophy, and adenoid hypertrophy were independent risk factors for OSAHS (p < 0.001, p = 0.042, and p = 0.004, respectively). There was a positive correlation between the degree of obesity and AHI (r = 0.535; p < 0.001), and an inverse correlation between obesity and MinSao(2) (r = -0.507; p < 0.001). End-tidal CO(2), Paco(2), and bicarbonate levels were within the normal range.



Obesity is a risk factor for OSAHS, and the degree of obesity is positively correlated with the severity of OSAHS.

title: Impacts of body weight after surgery for obstructive sleep apnea in children
abstract: To investigate the impacts of body weight status on surgical outcomes and shifts of body weight status after adenotonsillectomy(T&A) in children with obstructive sleep apnea (From 2009 to 2011, 161 children (mean age, 7.0±3.4 years; 78% boys) were included. All the children had clinical symptoms and preoperative polysomnographic evaluations diagnosis of OSA. Children were divided into four weight status groups (underweight, normal weight, overweight and obese), based on age and gender corrected body mass index (Following T&A, the four different weight status groups significantly improved in apnea/hypopnea index (AHI) and minimum oxygen saturation. However, 49.1% of the children (79/161) had residual OSA (AHI ⩾1). The incidence of residual OSA (AHI ⩾1) in the obese group was 75%, which was significantly higher than the other three groups (P<0.01). Weight status changes after T&A were documented, and 54% (13/24) of the underweight children shifted to normal weight status within 6 months after surgery.Although sleep parameters improved in all weight statuses, obese children had a higher incidence of residual OSA postoperatively. About half of the underweight children shifted to normal weight status after T&A.

title: A comparison of tonsillar size and oropharyngeal dimensions in children with obstructive adenotonsillar hypertrophy.
abstract: Hypertrophy of the tonsils and adenoids is the most common cause of obstructive sleep apnea in children. There is relatively little known about the occurrence of subclinical variations in the dimensions of the oropharynx which may predispose to the development of obstructive sleep apnea in children without obvious craniofacial abnormalities. Fifty-one children (3-10 years) were divided into two groups: the first group consisted of 18 patients with small tonsils and no history of snoring who underwent tonsillectomy for chronic tonsillitis. They were compared to a second group of 33 patients with large tonsils who underwent tonsillectomy and adenoidectomy for symptoms of obstructive sleep apnea. Age, height, weight, body surface area and tonsil weight were correlated to the dimensions of the oropharynx obtained by direct measurement intraoperatively including the length of the soft palate, anterior-posterior depth of the nasopharynx and the distances between the medial tonsillar surfaces, anterior tonsillar pillars and lateral pharyngeal walls at mid-tonsil level. Increased patient height, weight and surface area correlated positively to increased distance between the lateral pharyngeal walls and to the length of the soft palate in the patients with small tonsils. No such correlation existed in the patients with obstructive adenotonsillar hypertrophy. In addition, the distance between the lateral pharyngeal walls was significantly decreased in the group with large, obstructing tonsils as compared to those with small tonsils and no history of obstruction (P less than 0.01). However, the patients with small tonsils and no obstruction had significantly longer soft plates (P less than 0.01) and less depth tot eh nasopharynx (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

title: Central sleep apnea in obese children with sleep-disordered breathing
abstract: In contrast to obstructive sleep apnea (OSA), central sleep apnea (CSA) in obese children has received lesser attention. As pediatric CSA is more prevalent than expected and adversely impacts health, this study aims to elucidate the major factors associated with central apnea index (CAI) and compare CSA between obese and non-obese children.Retrospective analysis was performed in a tertiary referral medical center. Children with sleep-disordered breathing (SDB) ranging from 2–18 years old were enrolled. All participants completed history taking, otolaryngological examination and overnight polysomnography. CSA was defined as having CAI exceeding 1 h−1. CAI and the prevalence of CSA were analyzed in children of different age groups, weight statuses and adenotonsillar sizes.A total of 487 cases were included. The prevalence of CSA was 13.3% (65/487). CAI was negatively correlated with age (r=−0.32, P<0.001). Obese children had a significantly lower CAI than that of non-obese ones (0.20±0.36 vs 0.48±0.82 h−1, P<0.001). Multiple linear regression analysis demonstrated a relationship between CAI, age and obesity as ‘CAI=0.883–0.055 × Age –0.22 × (Obesity)’.In children with SDB, younger ones have a significantly higher CAI than older ones. Additionally, obese children had a lower CAI than non-obese ones.

title: Validation of the Chinese version OSA-18 quality of life questionnaire in Taiwanese children with obstructive sleep apnea.
abstract: The OSA-18 questionnaire is one of the most widely-used sleep quality measurements in children. We tested the applicability and cross-cultural validation of the traditional Chinese version OSA-18 questionnaire.



This cross-sectional study was conducted in a tertiary medical referral center. The translation and cultural adaptation of the OSA-18 questionnaire were performed based on Brislin's revised model. A total of 109 children aged 2-18 years old with sleep problems were recruited. Overnight polysomnography and the OSA-18 questionnaire were administered. The reliability and validity of the traditional Chinese version of OSA-18 questionnaire were verified.



Excellent test-retest reliability and good internal consistency were achieved, and the validity of OSA-18 with overnight polysomnography was confirmed. The domain of sleep disturbance, daytime function, caregiver concerns, and the OSA-18 total scores were significantly higher in sleep apnea patients. The domain of caregiver concern had the highest score, while those of emotional distress had the lowest scores. The optimal cut-off point of the OSA-18 total scores for detecting obstructive sleep apnea was 67.



The traditional Chinese version of OSA-18 demonstrated high reliability and good validity in our study. The domain of caregiver concern is the major element in Taiwanese children with sleep-disordered breathing.

title: Roentgenologic Investigation of the Nasopharyngeal Tonsil in Children of Different Ages
abstract: Many otolaryngologists and pediatricians maintain that the methods employed clinically for estimating the volume of nasopharyngeal lymphoid tissue in children, i.e. the size of the so-called nasopharyngeal tonsil, are in many ways troublesome and unsatisfactory. The method most often employed, palpation through the mouth, is usually distressing, particularly for young patients. In many instances it is difficult to ascertain whether the findings thus established are pathologic; it is impossible to carry ont anterior or posterior rhinoscopy if the patient is not cooperative. Roentgen examination may reveal the size of the nasopharyngeal airway and the quantity of lymphatic tissue within it. The simplest way to perform the examination in children is to take a single lateral film of the nasopharynx. GOLDMAN & BACHMAN (1958) stated: 'Our experiences have revealed that the information obtained by radiography of the nasopharynx is usually more complete and accurate than that obtained by other methods, and can be related to the surgical scope when operation is indicated.

title: A radiological study of the adenoid in normal children.
abstract: In this study the radiology of the adenoid is compared in two groups of children: those selected for adenoidectomy and those with a history of head injury who had had a lateral radiograph of the skull. The size of the adenoid was found to be the same in both groups though the nasopharyngeal airway was found to be significantly smaller in the children selected for adenoidectomy. On the basis of measurements in the normal children a lower limit of normal is suggested for the width of the nasopharyngeal airway, this is 2 mm in the case of children below the age of 70 months and 3 mm in the case of children over 70 months old. Only 17% of the children selected for adenoidectomy have abnormally narrow nasopharyngeal airways.

title: Radiographic Evaluation of the Symptom-Producing Adenoid
abstract: Adenoid hypertrophy has several variable symptoms. In this study, symptoms were divided into minor and major. A lateral radiograph of the nasopharynx was performed in 114 patients to study the superior and antroadenoid diameters. With proper statistical analysis, a correlation was made between the various clinical groups (scores) and the adenoid measurements. Our results support Hibbert's findings that the antroadenoid width is a better indicator of the symptom-producing adenoid than adenoid mass measurements with their loosely defined norms. A thorough history and physical examination remain paramount in the diagnosis and management of adenoid hypertrophy.

title: The evaluation of radiographs of the nasopharynx.
abstract: Radiographs of the nasopharynx are sometimes misinterpreted because of poor technical quality. A simple method of interpretation is suggested based upon measuring the airway immediately behind the upper part of the soft palate. If it is narrower than the width of the soft palate it is considered as markedly obstructed. When narrower than half of the soft palate, it is severely obstructed. When it is the same width as the soft palate, it is not narrowed. One hundred and forty radiographs were evaluated by this method and by previously described methods. All methods showed good correlation and the present method is easy to use and easy to teach and has proven to be useful even in radiographs which other methods fail to interpret. The importance of evaluating the airway instead of the adenoidal thickness is stressed.

title: Assessment of adenoid size in children by fibreoptic examination.
abstract: In order to investigate the relationship between the size of the adenoid and upper respiratory symptoms in children, fibreoptic examination of the nasal cavity and nasopharynx was performed in 817 children. The size of the adenoid was classified into three categories according to the distance between the vomer and the adenoid tissue. There was a significant relation between the size of the adenoid and the complaints of nasal obstruction (P < 0.001) and of snoring (P < 0.001), but not with the presence of purulent sinusitis. In the whole population, the size of the adenoid correlated well with the results of tympanometry (P < 0.001), but this does not hold in all age groups. This study has confirmed adenoid hypertrophy as a common aetiological factor in children with the complaints of nasal obstruction and snoring. The enlargement of the adenoid only partially explains the occurrence of otitis media with effusion. The introduction of the flexible fibrescope in the examination of the nasal cavity and nasopharynx in children is of great clinical value, especially in the selection of children for adenoidectomy. It is a minor invasive examination well tolerated by most children, giving more information than a lateral skull radiograph and avoiding unnecessary radiation.

title: Validation of a new grading system for endoscopic examination of adenoid hypertrophy
abstract: To propose and validate a new subjective grading system of adenoid size with flexible fiberoptic evaluation.  Digital video clips of 24 flexible fiberoptic nasopharyngeal exams were presented to 24 examiners (otolaryngology resident and consultant physicians) at a tertiary care institution. Examiners were asked to use the proposed grading system to rate adenoid hypertrophy. Kappa statistical analysis was used to evaluate the degree of intergrader agreement or disagreement.  Statistical analysis of intergrader agreement demonstrated an overall Kappa score of 0.71 suggesting a “substantial” strength of agreement. The Kappa strength of agreement was found to be 0.83 (almost perfect) among consultant physicians and 0.62 (substantial) among resident physicians.  The proposed adenoid staging system is a reliable and consistent method of staging adenoid tissue size.  This new validated grading system may be a useful standard for reporting adenoid size in future clinical outcome studies.

title: Size assessment of adenoid and nasopharyngeal airway by acoustic rhinometry in children.
abstract: Adenoid hypertrophy is known as the most common cause of nasal obstruction in children; thus, adenoidectomy with, or without, tonsillectomy is one of the most commonly performed surgical procedures in the paediatric population. Although many methods have been suggested, few studies have reported on how to assess adenoid size, pre-operatively. Acoustic rhinometry is an objective technique as well as a non-invasive method, which can be easily used in young children. This study confirmed that acoustic rhinometry is a non-invasive and objective technique for assessing the geometry of the nasal cavity and nasopharynx. Forty children were evaluated using symptomology, two different radiological measurements and acoustic rhinometry; the results were compared with endoscopic findings. Clinical symptoms and A/N ratio measured with Fujioka's method significantly correlated with the endoscopic assessment findings (r = 0.769 and 0.604 respectively). Significant increases in the cross-sectional area and volume of the nasopharynx were observed at the adenoid notch after adenoidectomy (p < 0.005 and p < 0.005, respectively). Acoustic rhinometry showed a high degree of correlation of which adenoid occupied the nasopharyngeal airway under endoscopic examination (r = 0.771). Thus, the study concluded that acoustic rhinometry can be as good an objective method for measuring adenoid sizes as endoscopy and can be used as one of the pre-operative examination tools for adenoidectomy.

title: Plain radiographic evaluation of the nasopharynx: do raters agree?
abstract: Subjective plain radiographic evaluation of the nasopharynx has been a widely adopted technique. Although it has its own limitations, its ease of interpretation and simplicity are some of its advantages.



To investigate the reliability, using kappa, in subjectively reporting plain nasopharyngeal radiographs in children with symptoms suggestive of enlarged adenoids.



This was a retrospective study of the clinical records, and plain X-rays of the nasopharynx of paediatric patients with clinical features of adenoid hypertrophy in a Nigerian Tertiary Health Institution from January 2008 to December 2008.



Fifty-one children with a mean age of 3.4 years; standard deviation of 2.772 was studied. They had an age range of 2 months to 12 years. Most (66.6%) of the children studied were in the age bracket 0-4 years. The inter-rater reliability between the two Otolaryngologists, and that between an Otolaryngologist and a Radiologist using kappa statistics were 0.6696, 95% CI (0.5035-0.8357; p<0.05) and 0.8182, 95% CI (0.7073-0.9291; p<0.05) respectively. While the kappa intra-rater reliabilities for the two Otolaryngologists were 0.6931, 95% CI (0.5473-0.8389) and 0.9591, 95% CI (0.9033-1.000).



There was a high level of agreement among trained raters, in subjectively interpreting plain nasopharyngeal radiographs in children with suspected adenoidal obstruction.

title: Video fluoroscopy for evaluating adenoid hypertrophy in children.
abstract: Adenoid hypertrophy is a common cause of upper airway obstruction in children. Traditionally, adenoid size has been evaluated using a conventional lateral skull film. Flexible endoscopy is now the gold standard for the evaluation of the upper airway. Children need to be cooperative in order to complete a videonasopharyngoscopy examination, which is not always possible.



The purpose of this paper is to determine the sensitivity and specificity of lateral video fluoroscopy for assessing adenoid size compared to conventional lateral skull films with videonasopharyngoscopy as the gold standard.



Twenty pediatric patients with adenoid hypertrophy demonstrated by videonasopharyngoscopy, and 20 control patients without adenoid hypertrophy were assessed with video fluoroscopy and lateral skull radiograph. Two independent examiners evaluated all studies. Specificity, sensitivity, and predictive values were obtained for findings on video fluoroscopy and lateral skull film.



Video fluoroscopy showed 100% sensitivity, and 90% specificity for the diagnosis of adenoid hypertrophy. Lateral skull films showed 70% sensitivity, and 55% specificity. A Spearman correlation coefficient demonstrated a significant correlation (P<0.05) between findings on video fluoroscopy and videonasopharyngoscopy. In contrast, there was a no significant correlation (P>0.05) between lateral skull films and videonasopharyngoscopy.



Video fluoroscopy appears to be a safe and reliable procedure for assessing adenoid hypertrophy in children.

title: Correlation between adenoid-nasopharynx ratio and endoscopic examination of adenoid hypertrophy: a blind, prospective clinical study.
abstract: To determine the reliability of adenoid-nasopharynx (A/N) ratio that is calculated on lateral cephalometric graphies for measuring the adenoid tissue size.



85 patients that had been examined in our clinic with a prediagnosis of adenoid hypertrophy between June 2007 and March 2008 were included in the study. Local ethics committee approved the study protocol. Patients who had a previous adenoidectomy history and anatomic anomaly or acute infection in nose, palate or nasopharynx were excluded. Endoscopic nasal examination was done in all patients in addition to the routine ear nose throat examination. Lateral cephalometric graphs were obtained from all patients. Digital images obtained during endoscopic examination were evaluated on computer and obstruction ratios of adenoid tissue to choanal opening were calculated. Each cephalometric graph was evaluated by a blinded author. A/N ratio was calculated by dividing the distance from the outermost point of convexity of adenoid shadow to basiocciput to the distance between sphenobasiocciput and posterior end of hard palate (Fujioka Method). A/N ratio of each patient was then compared with the obstruction ratio obtained in nasal endoscopy. Pearson correlation test was used for statistical analysis and a p-value of <0.05 was accepted as significant.



There were 52 male and 33 female patients between the ages of 2 and 12 years (mean age, 5.0+/-2.2; median, 4.5). In nasal endoscopy, adenoid tissue was determined to obstruct the choanal opening as 88.5+/-12.0% (range, 51-99%) in an average. Mean adenoid nasopharynx ratio was found to be 0.87+/-0.1. There was a statistical significant correlation between A/N ratio and nasal endoscopic examination findings (r=0.511; p<0.0001).



A/N ratio is an easily applicable, noninvasive method that can correctly measure the size of the adenoid tissue in patients who are suspected to have adenoid hypertrophy.

title: Assessment of adenoid size: A comparison of lateral radiographic measurements, radiologist assessment, and nasal endoscopy.
abstract: Correlate adenoid size as determined by lateral neck radiographs and intra-operative mirror exam. Determine if a radiologist's assessment of the lateral neck X-ray correlates with adenoid size. Assess the correlation of endoscopic findings to the degree of adenoid hypertrophy seen on intra-operative mirror exam. To perform a cost analysis of radiographic and endoscopic evaluations of the adenoids.



Retrospective study.



Patients who underwent adenoidectomy were reviewed. The adenoid size as determined by the adenoid-to-nasopharyngeal (A/N) ratio, radiology report, and flexible nasal endoscopy were compared to the adenoid size as determined by intra-operative mirror nasopharyngeal exam. Compensation rates for each modality were compared.



Sixty-one children had pre-operative airway radiography. Ninety-nine patients underwent flexible nasopharyngoscopy. When the A/N ratio was compared to the intra-operative mirror exam, the Pearson Correlation coefficient was 0.64 (p<0.0001). The radiology reading was compared to intra-operative mirror exam and the Spearman Correlation coefficient was 0.29 (p=0.0258). When endoscopic nasopharyngoscopy was compared to intra-operative mirror exam, the Pearson Correlation coefficient was 0.62 (p<0.0001). The cost of nasal endoscopy was $654. Lateral airway radiography plus radiology interpretation cost $605.



Children who undergo lateral radiographs to assess adenoid size are younger than those who undergo awake flexible endoscopic nasopharyngoscopy. Both the A/N ratio and endoscopic nasopharyngoscopy correlate well with the findings of the intra-operative mirror exam. The radiologist interpretations that do not utilize the A/N ratio measurement do not correlate well with intra-operative mirror exam findings. Both modalities are comparable in cost.

title: Plain radiographic evaluation of children with obstructive adenoids.
abstract: There are several methods of evaluating adenoidal size pre-operatively. Plain nasopharyngeal radiography is a common investigative modality: it has been advocated, and also condemned.



This study was intended to assess nasopharyngeal airway obstruction by the adenoids using plain X-rays; and also to find correlation if any, with the symptomatology.



This is a retrospective study carried out between January and December 2008. The case notes and plain X-rays of the nasopharynx of 34 paediatric patients with clinical features of obstructive adenoids were analyzed.



A total of 34 children were studied, 22 (64.7%) were males and 12 (35.3%) were females. Their ages ranged between 7 months and 10 years: mean age was 3.55 years, standard deviation 2.723. Majority (67.6%) of the children were in the age group 0-4 years. The lowest symptomatology assessment score was 0 and the highest was 3. Children 4 years and below had the highest symptomatology scores. The minimum adenoidal-nasopharyngeal ratio was 0.35 and the maximum was 0.94. There was no significant difference in the mean adenoidal-nasopharyngeal ratio of males and females (t=0.407; p=0.692). Many (75.0%) of the children with moderate to severe nasopharyngeal airway obstruction by the adenoids were in the age bracket 0-4 years. The lowest adenoidal-nasopharyngeal ratio score was 0 and the highest was 3. Children 4 years and below had the highest adenoidal-nasopharyngeal ratio scores. There was a very weak nonsignificant correlation between the symptomatology assessment score and the radiological assessment score (r=0.168; p=0.375).



The adenoidal-nasopharyngeal ratio is reliable in assessing the nasopharyngeal airway in children with obstructive adenoids.

title: Adenoid size is related to severity but not the number of episodes of obstructive apnea in children.
abstract: The objective of this study was to determine the extent to which adenotonsillar hypertrophy contributes to the severity of obstructive sleep apnea (OSA) in children.



Thirty-three consecutive children who were referred to a sleep disorders center for evaluation of suspected OSA had standard lateral neck roentgenography performed. Adenoid size was determined by measuring the adenoidal-nasopharyngeal (AN) ratio. Tonsil size was quantitated on physical examination. The severity of OSA was determined by full-night polysomnography in the sleep laboratory.



All of the patients reported snoring with trouble breathing, apneas, or both problems witnessed by a parent. The patients' respiratory disturbance index ranged from 0 to 95.3 (mean +/- SD 12.5 +/- 9.1). The patients' AN ratio ranged from 0.48 to 0.98 (0.76 +/- 0.14); 30 (91%) of the 33 patients had AN ratios greater than published normal means, and 16 (48%) had AN ratios more than 2 standard deviations above published means. Although the AN ratio and tonsil size did not predict the number of apneas, a significant relationship was seen between the AN ratio and the duration of obstructive apneas (r = 0.48, p < 0.01). Obesity (percent ideal body weight) was the only independent predictor for the number of respiratory events per hour of sleep (r = 0.49, p < 0.01). Percent ideal body weight was also the major predictor of the lowest oxyhemoglobin saturation (r = -0.58, p < 0.0001), but the AN ratio also contributed to the variance in saturation, with a correlation coefficient (r) of 0.69 for the two factors (p < 0.0001).



Lymphoid hyperplasia affects the severity of apnea more than the number of obstructive apneas. The pathophysiologic characteristics of OSA in children probably involve complex interactions between pharyngeal size and mechanics.

title: OSAS in children: Correlation between endoscopic and polysomnographic findings
abstract: To correlate polysomnographic findings with clinical history of apnea, the degree of obstruction caused by tonsillar hypertrophy, and to age group.  267 children with a clinical diagnosis of obstructive sleep apnea (OSAS) were evaluated. Patients were divided into preschool- and school-age categories, and subdivided in 3 additional groups, according to tonsillar hypertrophy. Polysomnographic findings were compared within groups.  34% of children had history of OSAS and normal polysomnographic findings. Tonsillar hypertrophy was correlated to more severe apnea among preschool-age children, but not among school-age children. Among children with tonsillar hypertrophy, more severe apnea was observed in preschool-age children than in school-age children.  There is little correlation between polysomnographic and clinical findings in children with OSAS.  Adenotonsillar hypertrophy leads to more severe polysomnographic patterns in preschool-age children. More severe apnea is observed in younger children with adenotonsillar hypertrophy than in older ones.

title: The correlation among obesity, apnea-hypopnea index, and tonsil size in children.
abstract: The correlation between obesity and severity of obstructive sleep apnea (OSA) is well established in adults, but data are inconsistent in children. We hypothesized that there is a significant correlation between the degree of obesity and the severity of OSA in children.



We retrospectively reviewed records of weight, height, history, and polysomnography of all 1- to 15- year-old children referred to our sleep laboratory. Children with known anomalies and repeated polysomnography were excluded from this study. Obesity was defined as body mass index z score (BMI Z score) > 1.96. The correlation between BMI Z score and apnea-hypopnea index (AHI) was assessed. Possible confounding factors, ie, age, gender, and tonsil size, were adjusted by multiple linear regression.



Four hundred eighty-two children were included in this study. Obese children had a significantly higher AHI (median, 1.5; interquartile range [IQR], 0.2 to 7.0) than the AHI of nonobese children (median, 0.7; IQR, 0.0 to 2.5). BMI Z score was significantly correlated with log-transformed AHI (Ln[AHI]) [r = 0.156, p = 0.003]. BMI Z score and tonsil size were still correlated with Ln(AHI) even after adjusted for other confounding factors (p = 0.001).



Degree of obesity as measured by BMI Z score and tonsil size are significantly related to severity of OSA as reflected by the AHI, although the correlation is mild.

title: Pediatric tonsil size: Objective vs subjective measurements correlated to overnight polysomnogram
abstract: To compare subjective and objective tonsil size measurements (weight, volume, intertonsillar distance) along with simple pharyngeal measurements in the prediction of pediatric obstructive sleep apnea hypopnea syndrome (OSAHS) severity.  Tonsil size (0–4+) and Mallampati/Friedman palate position were subjectively measured. During adenotonsillectomy, tonsil size was objectively measured along with simple pharyngeal dimensions. Spearman rank correlation coefficients were calculated and forward and reverse stepwise multivariate regression modeling was used to assess the prediction of preoperative OSAHS severity as determined by polysomnogram (PSG). Evaluation of possible outlier influence was also performed.  Thirty-four pediatric patients (median age, 4; range, 2–9) were included. Objective tonsil weight (Spearman's ρ = 0.6143, P = 0.0002), tonsil volume (ρ = 0.4960, P = 0.0039), and intertonsillar distance (ρ = −0.7559, P < 0.0001) were strongly correlated with subjective tonsil size but not with age, body mass index (BMI), or preoperative apnea-hypopnea index (AHI). Regression modeling demonstrated that only measured tonsil weight (β = 1.43, P = 0.003), age (β = −3.21, P = 0.001), and hard palate length (β = 0.979, P = 0.003) were significant predictors of the preoperative AHI (R2 = 0.5358). Evaluation of possible outliers indicated tonsil weight was the most robust predictor of preoperative AHI.  Subjective tonsil size measurements correlate well with objective tonsil volume measurements. However, only objective tonsil measurements were significantly predictive of objective PSG-measured OSAHS severity.

title: Tonsil volume, tonsil grade and obstructive sleep apnea: is there any meaningful correlation?
abstract: The aims of this study were to evaluate the correlation between oropharyngeal examination and objective palatine tonsil volume in snoring adults and verify the influence of the oropharyngeal anatomy, body mass index, age, and severity of obstructive sleep apnea on actual tonsil volume. In addition, we aimed to assess the influence of tonsil size on obstructive sleep apnea in adults.  Pharyngeal wall geometry is often altered in adults who have obstructive sleep apnea, and this might influence the findings of the oropharyngeal examination that, in turn, are the key factors when considering surgical management for this condition. Furthermore, the correlation between the actual tonsil volume and the severity of obstructive sleep apnea in adults is currently unknown.  We prospectively studied 130 patients with obstructive sleep apnea or primary snoring who underwent pharyngeal surgery with intraoperative measurement of tonsil volume. We compared tonsil volume with preoperative polysomnography, oropharyngeal examination, and anthropometric data.  We found a significant correlation between actual tonsil volume and subjective tonsil grade. We also found a significant correlation between tonsil volume and the apnea-hypopnea index. Using a multivariate linear regression model, tonsil volume was found to be significantly correlated with age, body mass index, and oropharyngeal examination, but not with polysomnography. Clinically, only the rare tonsil grade IV was indicative of more severe obstructive sleep apnea.  There is a strong correlation between clinical tonsil grade and objective tonsil volume in snoring adults, and this correlation exists regardless of the presence or severity of obstructive sleep apnea. Pharyngeal tissue volume likely reflects the body mass index rather than obstructive sleep apnea severity.

title: Tonsillar size in 2‐ to 14‐year‐old children with and without snoring
abstract: Few investigations have assessed tonsillar size in children of variable age, sleep‐disordered breathing (SDB) status and degree of adiposity. This study evaluated the size of tonsils in young and older, lean and obese children, without or with snoring.

title: Is there a clear link between overweight/obesity and sleep disordered breathing in children?
abstract: The proportion of children who are overweight or obese has risen steadily in recent decades and approaches a quarter of all children in Western countries. This global epidemic of excess weight and adiposity in humans is associated with increased morbidity and mortality, especially related to diabetes and poor cardiovascular health. It would appear that obesity is also generally accepted to be an important risk factor in the development of sleep disordered breathing (SDB), in children as well as adults. The article, "The prevalence, anatomical correlates and treatment of sleep-disordered breathing in obese children and adolescents", by Verhulst et al., also in this issue, reviews evidence supporting the view that obese children are at higher risk of developing SDB. We believe, however, that the available studies do not support a straightforward association of overweight or obesity with increased prevalence of SDB. Rather, the available data is clearly equivocal mainly due to methodological differences between the previous studies. This review nonetheless examines the factors which may modulate the relationship between overweight or obesity and prevalence of SDB, particularly ethnicity and age.

title: Three-dimensional computed tomographic analysis of airway anatomy in patients with obstructive sleep apnea.
abstract: To identify abnormalities in airway size and shape that correlate with the presence and severity of obstructive sleep apnea (OSA).



This was a retrospective case series of patients undergoing treatment of OSA who had preoperative computed tomographic (CT) scans of the upper airway available. Patients who had undergone CT scanning for nonairway pathologic features during the same period served as the controls. Digital 3D-CT reconstructions were made and 12 parameters of airway size and 4 of shape were analyzed. The posterior airway space, middle airway space, and hyoid to mandibular plane distance were measured on the lateral cephalograms of the patients with OSA. Bivariate analysis was used to identify the factors associated with the presence and severity of OSA as measured by the respiratory disturbance index (RDI). Multiple regression analysis identified the factors that correlated with the RDI.



Of the 44 patients with OSA, 15 (10 men and 5 women) had pre- and postoperative CT scans available. In addition, 17 patients (11 men and 6 women) were used as controls. The airway length was significantly increased in the patients with OSA (P < .01). On bivariate analysis, the length, lateral/retroglossal anteroposterior dimension ratio and genial tubercle to hyoid bone distance were associated with the RDI (P < .03). On multiple regression analysis, length (P < .01) had a positive correlation and the lateral/retroglossal anteroposterior dimension ratio (P = .04) an inverse correlation with the RDI.



The results of this study indicate that the presence of OSA is associated with an increase in airway length. Airways that were more elliptical in shape and mediolaterally oriented (greater lateral/retroglossal anteroposterior dimension ratio) had a decreased tendency toward obstruction.

title: Magnetic resonance imaging in the evaluation of anatomical risk factors for pediatric obstructive sleep apnoea-hypopnoea: a pilot study.
abstract: Aim of our study was to identify anatomical risk factors involved in the development of pediatric OSAHS through a MRI-based case-control pilot study.



MRI exams of the head and neck of 40 children affected by OSAHS were retrospectively evaluated. 25 indices referring to the air lumen, soft tissues and craniofacial skeleton were measured. Subsequently, the same process of measurement of indices was performed on MRI exams of 40 controls. For each index, then, we calculated in both groups mean, standard deviation, standard error and t value. Comparing the two series we finally calculated the degree of significance of each difference between children with OSAHS and controls through the Student's t-test.



Besides the expected and previously described differences of minimum retropharyngeal cross-sectional area (CSA), nasopharyngeal airway, combined upper airway volume, tonsillar and adenoid cross-sectional and volumetric indices, we found a higher midsagittal CSA of the soft palate and lower position of the hyoid bone, SNB angle and mandibular volume.



Results from our study population, certainly limited in terms of number of patients and considered age range, showed that not only adeno-tonsillar hypertrophy is important in determining the clinical syndrome: soft palate enlargement and certain skeletal pattern can even assume greater importance in the genesis and in the progression of the obstruction. MRI proved to be an accurate technique in the evaluation of the prevalent risk factor in children affected by OSAHS, leading to the most appropriate surgical approach.