Development of the nasopharynx: A radiological study of children.

The relation between pharyngeal tonsil and the bony nasopharynx determines the nasopharyngeal airway patency. Despite its importance, an anatomical study utilizing advanced imaging has not been conducted. The aim of the study was to evaluate the pharyngeal tonsil and bony nasopharynx depth and their ratio (adenoid-nasopharyngeal ratio [ANR]) with relation to sex and age in the general pediatric population. After excluding reported history of adenoidectomy, acute upper airway illness, allergy, and poor quality, 200 randomly selected head computed tomographies (CTs) of children were evaluated. CTs were divided into five age groups (0-5, 5.1-8, 8.1-11, 11.1-14, and 14.1-17 years). For each CT scan, the pharyngeal tonsil, bony nasopharynx and ANR values were calculated. A significant difference was found in the bony nasopharynx and pharyngeal tonsil depth between the five age subgroups (P < 0.001). Both bony nasopharynx and pharyngeal tonsil depth significantly increased between the age groups of 0-5 years to 5.1-8 years (4.17 mm increase, P < 0.001 and 3.47 mm increase, P < 0.009, respectively). The pharyngeal tonsil depth gradually decreases following the age of 8 years. No difference was found between age groups beyond age of eight for both the pharyngeal tonsil tissue and the bony nasopharynx. The ANR has an upward trend in the age group of 5.1-8 years. No sexual predilection was found. The bony nasopharynx and the pharyngeal tonsil tissue both grow during childhood. Different growth rates result in the narrowest airway in the age group of 5.1-8 years (ANR peak). These growth curves should be taken under consideration when treating pediatric pharyngeal tonsil hypertrophy. Clin. Anat., 33:1019-1024, 2020. © 2019 Wiley Periodicals, Inc.

Beneficial effects of a lifestyle intervention program on C-reactive protein: impact of cardiorespiratory fitness in obese adolescents with sleep disturbances.

The objectives of this study were to assess the relationship between inflammation and obstructive sleep apnea (OSA) and determine whether the lifestyle program's effects on inflammatory markers are associated with changes in anthropometric parameters, cardiorespiratory fitness, sleep duration, and OSA severity in severely obese adolescents. Participants were aged 14.6 (SD 1.2) yr, with a body mass index (BMI) of 40.2 (SD 6.5) kg/m2. Sleep, anthropometric parameters, glucose metabolism, inflammatory profile, and cardiorespiratory fitness [V̇o2peak relative to body weight (V̇o2peakBW) and fat-free mass (V̇o2peakFFM)] were assessed at admission and at the end of a 9-mo lifestyle intervention program (LIP). Associations between C-reactive protein (CRP) concentrations and BMI, sex, oxygen desaturation index (ODI), sleep fragmentation, total sleep time (TST), and V̇o2peak were assessed via ANCOVA. Twenty-three subjects completed the study. OSA subjects ( n = 13) exhibited higher CRP concentrations and a trend for higher BMI than non-OSA subjects ( P = 0.09) at admission. After intervention, OSA was normalized in six subjects, and CRP significantly decreased in the OSA group and in the whole population. In both groups, leptin levels significantly decreased, whereas adiponectin concentrations increased. At admission, BMI adjusted for sex, arousal index, ODI, TST, and V̇o2peakBW was associated with CRP levels (adjusted r2 = 0.32, P < 0.05). The decrease in CRP concentrations postintervention was associated with enhanced V̇o2peakFFM adjusted for sex, weight loss, and changed sleep parameters (adjusted r2 = 0.75, P < 0.05). Despite higher amounts of CRP in OSA subjects, obesity severity outweighs the proinflammatory effects of OSA, short sleep duration, and low cardiorespiratory fitness. However, enhanced cardiorespiratory fitness is associated with the decrease of inflammation after controlling for the same parameters.

Patterns of adenoid and tonsil growth in Japanese children and adolescents: A longitudinal study.

Lymphoid tissues, such as adenoids (Ad) and tonsils (Tn), are suggested to undergo hypertrophy during childhood and involution in adulthood. Enlargement of Ad and Tn can cause transient obstruction of the respiratory airways, thus inducing obstructive sleep apnoea. To date, the standard Ad and Tn sizes have not been reported, and there are no explicit objective criteria for evaluating their sizes or deducing whether they have enlarged, reduced, or remained constant over time. Our previous cross-sectional study revealed the age-dependent airway occupation ratio of Ad and Tn in Japanese individuals. We conducted a longitudinal observational study of the Ad and Tn sizes in Japanese individuals aged 6-20 years. Ninety individuals were retrospectively enrolled. The average and standard deviation of the sizes was calculated in 5 age-based groups.

The relationship between allergic status and adenotonsillar regrowth: a retrospective research on children after adenotonsillectomy.

Adenotonsillar regrowth in children after adenotonsillectomy (T&A) for obstructive sleep apnea (OSA) is often seen in clinical treatment, however, the relationship between allergic disease and adenotonsillar regrowth remains unclear. In this retrospective study, children were assigned to either the recurrence or control group, and subdivided by age at operation. Among children over 36 months, those in the recurrence group had more allergic disease and higher IgE, IL-4, and IL-5 levels than the same-aged children in control group. The Paediatric Allergic Disease Quality of Life Questionnaire (PADQLQ) scores for nasal symptoms and activity were higher in children older than 36 months in recurrence group. The results of immunohistochemistry and immunofluorescence showed that FoxP3+ cells (Tregs) were less, while GATA3+ cells (Th2 cells) were more in recurrence group for all ages. Allergic status and low levels of FoxP3 were proved as independent risk factors for adenotonsillar regrowth by multivariate logistic regression. These results indicate that allergic disease is a risk factor for adenotonsillar regrowth in children following T&A for OSA, and this risk increases with age. The decreased level of Tregs and subsequent changes in immune function play an important role in the pathogenesis of adenotonsillar regrowth.

Impact of partial and total tonsillectomy on adenoid regrowth.

OBJECTIVES/HYPOTHESIS: To compare the rates of adenoid regrowth in children who underwent total tonsillectomy and adenoidectomy (TA) versus partial intracapsular tonsillectomy and adenoidectomy (ITA). STUDY DESIGN: Retrospective cohort study. METHODS: A medical database was used to retrieve the records of 5,120 children younger than 12 years of age who had an adenoidectomy in combination with a tonsil surgery between April 2008 and September 2014. Children who had symptomatic obstructive sleep apnea without a history of recurrent tonsillitis, and underwent an endoscopic adenoidectomy with a microdebrider, in addition to a traditional tonsillectomy or partial tonsillectomy with coblation, were included in the study. Adenoid regrowth was evaluated in the children who completed at least a 1-year follow-up. The sizes of adenoids were subjectively graded and reported based upon a numerical scale. RESULTS: In total, 1,504 and 1,340 children met the inclusion, and were comprised of ITA and TA groups, respectively. Adenoid regrowth was seen in 98 (7.3%) children in the TA group after 1-year follow-up. Symptomatic adenoid regrowth was seen in 19 (1.4%) children in the TA group. In the ITA group, although 71 (4.7%) children had adenoid regrowth, only one (0.06%) reached grade 3 hypertrophy that could be attributed to nasal obstruction at 1-year follow-up. Comparison of the regrowth rates of both groups at the end of the 1-year follow-up period showed a statistically significant difference (P < .001). CONCLUSIONS: ITA seems to be a safe procedure with a low incidence of regrowth of adenoid tissue in children with adenotonsillar hypertrophy when compared to TA. LEVEL OF EVIDENCE: 4. Laryngoscope, 127:753-756, 2017.

[Nasopharyngeal changes in 8-13 years old healthy children in China: a longitudinal study].

Objective: Nasopharynx is an important compartment of the upper airway. It is closely associated with the characteristic craniofacial skeletal pattern related to sleep breathing. The present study aimed to investigate the growth pattern of the nasopharynx during rapid puberty growth period. Methods: Thirty non-snoring children (aged 8 to 11 years old) were selected by means of questionnaires and clinical examination. Periodic yearly follow up using MRI, lateral cephalogram, and polysomnograph (PSG) was done in these children. Fifty-one final mixed longitudinal samples were consisted of 23 children completed three consecutive follow-up, and 5 children completed two consecutive follow-up. The yearly changes of the nasopharynx and craniofacial structures were measured. ANOVA was used to evaluate the yearly growth of the nasopharynx. Correlated analysis was used to explore the potential influencing factors of craniofacial structures. Results: The rapid growth period of the nasopharynx located in the age range of 8-10 years old, during which the transverse dimension of the nasopharynx developed rapidly, while the rapid development of the sagittal dimension of the nasopharynx was around 12-13 years old. The growth of the nasopharynx was continuous. The changes in the cross-sectional area of the nasopharynx (⊿CSA) was positively correlated with the changes in distance between mandible of glossopharyngeus (⊿M), distance of hyoid to cervical anterior surface (⊿H-CVP), and anterior pharyngeal distance of glossopharyngeus (⊿AD) (r=0.363, 0.363, 0.323, respectively, all P<0.05). The changes in the volume of the nasopharynx (⊿V) was positively correlated with the changes in upper facial height (⊿N-ANS), ⊿M, and ⊿AD (r=0.336, 0.413, 0.478, respectively, all P<0.05). The changes in the sagittal dimension of the nasopharynx (⊿S) was negatively correlated with angulation in supramental and anatomical horizontal line (⊿SNB) (r=-0.322, P=0.045). The changes in the transverse dimension of the nasopharynx (⊿T) was negatively correlated with the changes in adenoid (⊿A) (r=-0.411, P=0.009). Conclusions: The growth and development of the nasopharynx was early and continuous, which could be affected by the development of either maxilla or mandible.

Morphometric growth changes of the nasopharyngeal space in subjects with different vertical craniofacial features.

INTRODUCTION: The purpose of this study was to morphometrically investigate the growth pattern of the adenoids in growing subjects with hyperdivergent and hypodivergent vertical craniofacial features. METHODS: In this retrospective study, we used a longitudinal sample of lateral cephalometric radiographs of 28 hyperdivergent and 30 hypodivergent subjects from 4 to 13 years of age. The radiographs were obtained from the American Association of Orthodontists Foundation Craniofacial Growth Legacy Collection. Measurements were made using digital tracings of the lateral cephalograms and point distribution models. Mixed-model analyses were used for statistical analysis. RESULTS: The mean distance between the sphenoid bone and the posterior nasal spine increased up to 5.3 mm over a 9-year span (95% CI, 4.1-6.5 mm; P <0.001). Furthermore, the mean distance between the sphenoid bone and the posterior nasal spine differed significantly (P = 0.029) between facial types; it was consistently greater (1.8 mm; 95% CI, 0.2-3.3 mm) in the hyperdivergent group. The nasopharyngeal airway area showed a trend to increase with age up to 12-fold (P <0.001). A significant interaction (P = 0.004) was found between age and facial type. Assessment of the adenoid shapes showed greater convexities in the hyperdivergent group, which were observable from an earlier age and for a longer duration. CONCLUSIONS: Clear differences in the morphometric growth pattern of the adenoids were found between facial types. Evaluation of adenoid shapes showed more prominent convexities that lasted longer in the long facial types than in the short facial types.

Regrowth of the adenoids after adenoidectomy down to the pharyngobasilar fascial surface.

OBJECTIVES: This study aimed to explore adenoid regrowth after transoral power-assisted adenoidectomy down to the pharyngobasilar fascial surface. METHODS: Transoral adenoidectomy down to the pharyngobasilar fascia surface was performed on 39 patients under endoscopic guidance, using a power-assisted system. The operation time, amount of blood loss and iatrogenic injury, presence of complications, and success and regrowth rates were recorded to assess the feasibility, safety and effectiveness of our surgical technique. RESULTS: In this adenoidectomy procedure, the pharyngobasilar fascia was left intact. The estimated blood loss was 5-50 ml (mean 15 ml), and the success rate was 97.3 per cent. Early complications occurred in 2.3 per cent of patients, while no long-term complications occurred in the cohort. No regrowth was found in the follow-up assessments, which were performed for 18-36 months after surgery. CONCLUSION: Adenoid regrowth was rare after adenoidectomy down to the pharyngobasilar fascial surface. The pharyngobasilar fascia can therefore be considered a surgical boundary for adenoidectomy.

Age-dependent changes in the size of adenotonsillar tissue in childhood: implications for sleep-disordered breathing.

OBJECTIVE: To analyze age-associated changes in linear and cross-sectional area (CSA) measurements of adenoid, tonsils, and pharyngeal lumen. STUDY DESIGN: Measurements were completed in head magnetic resonance imaging examinations performed for diagnostic purposes. Linear and nonlinear regression models were applied to describe the effect of age on the size of soft tissues and upper airway. RESULTS: Magnetic resonance imaging data were analyzed in 149 children without snoring (aged 0-15.9 years) and in 33 children with snoring (aged 1.6-15 years). In the children without snoring, adenoid size increased during the first 7-8 years of life and then decreased gradually [% (adenoid oblique width/mental spine-clivus length) = 11.38 + 1.52 (age) - 0.11 (age)(2), R(2) = 0.22, P < .01; adenoid CSA = 90.75 + 41.93 (age) - 2.47 (age)(2); R(2) = 0.50; P < .01]. Nasopharyngeal airway CSA increased slowly up to age 8 years and rapidly thereafter. Similar patterns were noted for the tonsils and oropharyngeal airway. In contrast, in children with snoring, adenoid and tonsils were large irrespective of age, and nasopharyngeal airway size increased slowly with age. CONCLUSIONS: In children without snoring, growing adenotonsillar tissue narrows the upper airway lumen to variable degrees only during the first 8 years of life. In contrast, in children with snoring, appreciable pharyngeal lymphoid tissue enlargement is present during the preschool years and persists beyond the eighth birthday.

Role of endoscopic nasal examination in reduction of nasopharyngeal adenoid recurrence rates.

OBJECTIVES: To evaluate the benefit of endoscopic examination after adenoidectomy in detecting residual adenoid tissue that would need completion surgery, in ultimate aim to reduce rates of adenoid recurrence. METHODS: A total of 312 children were included in the study conducted at Ain-Shams University Hospital from January till December 2007, following routine adenoidectomy, 118 had a nasal and nasopharyngeal rigid fiberoptic examination and 194 did not, randomly according to the surgical subunit that performed the surgery. Patients were followed up for a minimum of 2 years for recurrence of symptoms of adenoid enlargement. RESULTS: Endoscopic examination revealed that 14.5% of patients undergoing adenoidectomy had residual adenoid tissue that needed further removal, of these the most common site was at the lateral walls of the nasopharynx (47%). The recurrence rate of adenoid hypertrophy needing re-surgery with endoscopic examination (0.85%) approaches that of the lowest recorded (0.5%) with more expensive and costly methods, and statistically significant lower than rates when endoscopy is not performed (5.6%). Additional time needed for such examination was negligible in terms of cost-benefit relationship. CONCLUSION: Rigid fiberoptic endoscopy of the posterior choana and nasopharynx at the end of adenoidectomy provides the benefit of detecting unremoved adenoid tissue without significantly extra cost, time, nor expertise, and helps reduce significantly the rates of recurrence of adenoid enlargement, which might be attributed to residual "missed" adenoid tissue.

Estudo longitudinal do desenvolvimento da oclusão entre as fases de dentição decídua e mista e a influência dos hábitos bucais deletérios e da adenóide hipertrófica / Longitudinal study of occlusion development between primary and mixed dentitions and the influence of deleterious oral habits and hypertrophied adenoids

O objetivo deste estudo foi determinar a incidência de maloclusão em um estudo longitudinal de 5 anos de crianças escolares e verificar a hipótese que indivíduos com maloclusão prévia são mais propensos em manter as mesmas características na transição da dentição decídua para a mista e associar com os fatores etiológicos. Os indivíduos, com idade idades entre 8 e 11 anos, foram selecionados aleatoriamente de uma amostra representativa. Os critérios de inclusão foram oclusão normal na dentição decídua (150 crianças) ou as seguintes maloclusões (150 crianças): mordida aberta anterior e/ou mordida cruzada posterior e/ou trespasse horizontal maior que 3mm, desde que não submetidas a tratamento ortodôntico...

The effect of adenotonsillectomy on changes of position during sleep in pediatric obstructive sleep apnea syndrome.

BACKGROUND: It is unknown whether adenotonsillectomy influences changes of position during sleep in children with obstructive sleep apnea syndrome (OSAS). The aim of this study was to evaluate the effect of adenotonsillectomy on changes of position during sleep as determined by polysomnography in children with OSAS. METHODS: Forty-four polysomnograms from 22 children with OSAS were analyzed. We compared the frequency of positional changes during sleep and the distribution of sleep positions before and after adenotonsillectomy. RESULTS: Adenotonsillectomy significantly improved all respiratory parameters studied. The arousal index and sleep efficiency were improved among the sleep parameters. There was a significant decrease in the total number of positional changes during sleep (p < 0.001) and positional change index (p < 0.001). The proportion of sleep time spent in the supine position was significantly increased (p = 0.001), and the proportions spent in lateral (p = 0.003) and up (p = 0.018) positions were significantly decreased. CONCLUSION: Significant changes were found in the frequency of positional changes during sleep and the distribution of sleep positions in children with OSAS after adenotonsillectomy.

The incidence of adenoidal regrowth after adenoidectomy and its effect on persistent nasal symptoms.

Objective of the study is to evaluate the effectiveness of adenoidectomy for children, to asses the rates of adenoidal regrowth and find out if the regrowth of adenoidal tissue affects persistent nasal symptoms post-surgery. A prospective study was carried out in the period of 2005-2007. The inclusion criteria for patients in the study were hypertrophic adenoid tissue and moderate or severe persistent nasal obstruction. One hundred and fifty children had undergone an adenoidectomy using consistent technique and visual control. Medium-term follow-up results were conducted 12-24 months (the mean follow-up period was 17.1 months) post-surgery, performing transnasal fibroscopy and completing the questionnaire. A total of 104 (69.3%) out of 150 patients polled. Children's parents answered the questions that were used for the subjective assessment of symptoms and to ascertain the history of the patient's nasal obstruction and upper respiratory tract infection prior to surgery. The age range was from 3 to 15, of which, 68 (65.3%) of them had undergone a transnasal fibroscopy. There was a significant reduction in symptoms that were displayed by children prior to the operation: there were 5.8% patients with nasal obstruction after the surgery, while incidences of upper airway infections dropped from 79.8 to 7.7% after surgery (P < 0.001). Eighty-six (82.7%) parents considered their child's well-being as "having improved" and they were "satisfied" with the results. Transnasal fibroscopy examinations identified some regrowth of adenoidal tissue in 13 cases (19.1%), with only 3 cases demonstrating adenoidal regrowth to grade 1. Adenoidal regrowth was correlative with the age of the patients (P = 0.048) and to numerous postoperative treatment with antibiotics (P = 0.032). Adenoids rarely regrow after surgery and where there were traces of adenoidal tissue, it did not manifest clinically. Nasal obstruction after the adenoidectomy is rhinogenic origin, not the cause of enlarged adenoids. Adenoidal regrowth more often occurs in children younger than five years old and in those patients who were treated postoperatively with antibiotics on numerous occasions.

Histological studies on the ontogeny of bovine palatine and pharyngeal tonsil: germinal center formation, IgG, and IgA mRNA expression.

The development and distribution of lymphocyte subsets in calf palatine and pharyngeal tonsil were examined. During prenatal development, B cells were distributed in the subepithelial area, and T cells and MHC class II(+) cells were found in the deep layer of B-cell area, respectively, in both tonsils. At neonatal stage, lymphoid follicle containing a few CD4(+) cells have been formed in both tonsils. IgG(+) and IgA(+) cells were found in the parafollicular and epithelial area. At 3 months old, many germinal centers were recognized in both tonsils. CD4(+) cells and IgG mRNA expression were detected in light zone of germinal centers. Many IgG, and IgA mRNA expressions also could be detected in the parafollicular and subepithelial area of both tonsils. The data suggest that both tonsils have an important role of local immune defense against invading antigen after birth. The comparison of the histological characteristics of tonsil and Peyer's patch during ontogeny is also discussed.

Growth of the nasopharynx and adenoidal development in Brazilian subjects.

The purpose of this research was to study the growth of the nasopharynx and adenoid development. Lateral cephalometric radiographs obtained from 320 white Brazilian subjects between 4 and 16 years of age were used. All the participants were nose breathers and none of them had previously undergone adenoidectomy. Tracings were made from the radiographs and cephalometric measurements were performed. The results showed that adenoid sagital thickness is larger in the age group 4 - 5 years and decreases progressively. There is a slight increase in the age group 10 - 11 years, but afterwards the decrease continues. However, the nasopharyngeal free airway space does not decrease in the age group 10 - 11 years, despite the increasing thickness of the adenoid. This is attributable to the downward displacement of the hard palate, resulting in an increase of the free airway space due to growth. Although the nasopharynx follows a growth pattern similar to that of the rest of the body, adenoid tissue does not. Adenoidal development seems to differ from that of other lymphatic tissues, showing a peculiar pattern that can be revealed when hypertrophy due to infections and allergies is eliminated.

Growth of the nasopharynx and adenoidal development in Brazilian subjects

O objetivo da pesquisa foi estudar o crescimento da nasofaringe e o desenvolvimento da adenóide. Foram utilizadas as radiografias cefalométricas de perfil obtidas de 320 indivíduos brasileiros brancos, cujas idades variavam entre 4 e 16 anos. Todos os participantes apresentavam respiração predominantemente nasal e não haviam sido submetidos previamente à adenoidectomia. A partir das radiografias foram feitos traçados cefalométricos, sobre os quais foram realizadas medições. Os resultados revelaram que a espessura sagital da adenóide é maior na faixa etária de 4 a 5 anos, regredindo, então, progressivamente, até a faixa etária de 10 a 11 anos, quando ocorre um leve aumento, voltando a diminuir em seguida. O espaço aéreo livre nasofaríngeo, entretanto, não diminui na faixa etária de 10 a 11 anos, mesmo diante do aumento da espessura da adenóide. Esse fato se deve ao deslocamento do palato duro para baixo, o que determina a ampliação do espaço aéreo livre em razão do crescimento. Apesar de a nasofaringe seguir um padrão de crescimento similar ao do resto do corpo, a adenóide não o segue. O desenvolvimento da adenóide parece ser diferente do dos demais tecidos de origem linfóide, apresentando um padrão peculiar que pode ser percebido quando se elimina a hipertrofia causada por infecções e alergias.

Las edades óseas y cronológicas como determinantes clínicos de la involución de los tejidos adenoideos / Bone and chronological ages as clinical markers of adenoidal tissue´s involution

El tejido adenoideo aparece como parte del anillo linfático de Waldeyer durante los primeros años de vida. Alcanza su máximo volumen a los 6 años de edad, comienza a desaparecer entre los 8 a 10 años de edad, reduciéndose a una pequeña cavidad faríngea en adultos. En presencia de adenoides hipertróficos, pueden existir alteraciones respiratorias y de crecimientos general en el niño. Para determinar patrones de involución adenoidea, fueron medidas áreas de tejido adenoideo y nasofaríngeas, usando telerradiografías de perfil, según el método de Handelman y Osborne. La edad ósea fue obtenida a través del análisis de madurez ósea de Bjõrk y Helm en radiografías de mano, comparadas con el atlas de madurez ósea de Canals. Se seleccionó una muestra de 5 grupos, cada una con 20 individuos entre 10 y 14 años de edad. Los resultados fueron analizados mediante regresión lineal y validados con análisis de varianza.

Involution of lymphoid organs in bottlenose dolphins (Tursiops truncatus) from the western Gulf of Mexico: implications for life in an aquatic environment.

Involution of lymphoid tissues in relation to age has not been defined for bottlenose dolphins (Tursiops truncatus). Twenty-five bottlenose dolphins from the coast of Texas and western Louisiana were examined and complete necropsies were performed with histological samples taken of nearly all tissues. Ages ranged from several days to 27 years. The histology of four lymphoid organs-thymus, pharyngeal tonsil, mucosa-associated lymphoid tissue (MALT) of the colon, and anal tonsil-was assessed. Numerical scores were assigned to specific morphological features, thus creating an involution score. Definable and scorable features of each organ were selected for evaluation and determination of loss of lymphoid elements. Neonatal dolphins were recorded as the reference standard for no involution. The highest score for each organ represented the greatest amount of retention of tissue elements. Thus, the lower the score, the greater degree of involution. Comparing involution scores to tooth age permitted an assessment of involution over time. The greatest degree of involution was found in the MALT of the colon. The MALT of the colon declined dramatically so that after age 10 it was absent from 4 of 14 animals and minimally present in 8 others. Thymic tissue also suffered a precipitous drop in volume after about age 5, but was found in animals up to 24 years of age. Involution was moderate and variable in both pharyngeal and anal tonsils. In some animals, these tissues were reduced in volume early, and prominent in others well into adult life (over 20 years).

Linear dimensions of the upper airway structure during development: assessment by magnetic resonance imaging.

The upper airway undergoes progressive changes during childhood. Using magnetic resonance imaging (MRI), we studied the growth relationships of the tissues surrounding the upper airway (bone and soft tissues) in 92 normal children (47% males; range, 1 to 11 yr) who underwent brain MRI. None had symptoms of sleep-disordered breathing or conditions that impacted on their upper airway. MRI was performed under sedation. Sequential T1-weighted spin echo sagittal and axial sections were obtained and analyzed on a computer. We measured lower face skeletal growth along the midsagittal and axial oropharyngeal planes. In the midsagittal plane the mental spine-clivus distance related linearly to age (r = 0.86, p < 0.001). Along this axis, the dimensions of tongue, soft palate, nasopharyngeal airway, and adenoid increased with age and maintained constant proportion to the mental spine-clivus distance. Similarly, a linear relationship was noted for mandibular growth measured along the intermandibular line on the axial plane and age (r = 0.78, p < 0.001). In addition, the intertonsillar, tonsils, parapharyngeal fat pads, and pterygoids widths maintained constant proportion to intermandibular width with age. We conclude that the lower face skeleton grows linearly along the sagittal and axial planes from the first to the eleventh year. Our data indicate that soft tissues, including tonsils and adenoid, surrounding the upper airway grow proportionally to the skeletal structures during the same time period.

Development of adenoids: a study by measurement with MR images.

Magnetic resonance (MR) imaging, which is able to demonstrate the actual size of adenoids by differentiating them from other soft-tissue structures, can be effectively used to study the normal development of adenoids. To assess the normal development of adenoids and to understand their role in the nasopharyngeal airway compromise, the adenoids of 290 children who had MR examination for other reasons were measured by midsagittal T1-weighted spin-echo MR image. The maximal thickness of adenoids (A), anteroposterior depth of the nasopharynx (N) and the adenoid-nasopharynx (A/N) ratios were obtained using this method. The results showed that of the infants under the age of 3 months only 2 out of 11 adenoids (18%) could be identified. By 4 months of age, adenoids could be identified in 6 of 8 infants (75%). After 5 months of age, all adenoids were well demonstrated by MR imaging. The adenoids developed rapidly during infancy and reached a plateau between 2- and 14 years of age with a mean thickness ranging from 10.7 to 12.2 mm. Finally, the adenoids regressed rapidly after 15 years old. The A/N ratios, which could be used to assess the airway compromise, had a plateau between 2- and 7 years of age. After that, with the steady growth of the nasopharynx, the possible role of adenoid in airway compromise will become increasingly less significant in later childhood.