Lateral cephalometric radiograph versus lateral nasopharyngeal radiograph for quantitative evaluation of nasopharyngeal airway space

Asymptomatic Otitis Media With Effusion in Children With Adenoid Enlargement

OBJECTIVES

To estimate the burden, and clinical factors associated with development of Otitis media with effusion (OME) in children with enlarged adenoids.

METHODS

Consecutive eligible patients with adenoid (sometimes with tonsillar) enlargement managed operatively in a period of five years. Patients had no complaints suggestive of hearing impairment. Age, sex, clinical diagnosis, and weight of patients were recorded. Otoscopic, audiometric, and radiological examinations findings were recorded. Tympanometry patterns were classified according to Jerger's classification; type B and C tympanograms represented OME. Some patients had Pure Tone Audiometry (PTA). Plain nasopharyngeal X-ray assessed the adenoid: nasopharyngeal (AN) ratio with >0.5 regarded as obstructive adenoid.

RESULTS

216 ears of 108 children were assessed. 49.1% of children were in age range 1-3 years, mean 3.6 ± 2.6 years. 62.0% were males, weight ranged from 7.8 to 31.0 kg, mean was 14.3 ± 5.2 kg. 63.9% had associated tonsillar enlargement. Mean AN ratio was 0.69 ± 0.07. Tympanometric findings showed prevalence of OME in all ears was 63/216 = 29.2%, consisting of 30.5% with unilateral (Right ear 19.4%, Left ear 11.1%), and 13.9% with bilateral OME. Acoustic reflexes were absent in both ears in 32 (29.6%) of the patients. There was normal hearing in 16/38 ears (42.1%), while others had different types of hearing loss. Two factors namely increased age and weight were significantly associated with OME in patients with Adenoid enlargement.

CONCLUSIONS

29.2% of children with adenoid enlargement had a co-morbidity of asymptomatic OME. The factors associated with OME were increased age and weight of the patients.

MR Image Analytics to Characterize the Upper Airway Structure in Obese Children with Obstructive Sleep Apnea Syndrome

Purpose

Quantitative image analysis in previous research in obstructive sleep apnea syndrome (OSAS) has focused on the upper airway or several objects in its immediate vicinity and measures of object size. In this paper, we take a more general approach of considering all major objects in the upper airway region and measures pertaining to their individual morphological properties, their tissue characteristics revealed by image intensities, and the 3D architecture of the object assembly. We propose a novel methodology to select a small set of salient features from this large collection of measures and demonstrate the ability of these features to discriminate with very high prediction accuracy between obese OSAS and obese non-OSAS groups.

Materials and Methods

Thirty children were involved in this study with 15 in the obese OSAS group with an apnea-hypopnea index (AHI) = 14.4 ± 10.7) and 15 in the obese non-OSAS group with an AHI = 1.0 ± 1.0 (p<0.001). Subjects were between 8–17 years and underwent T1- and T2-weighted magnetic resonance imaging (MRI) of the upper airway during wakefulness. Fourteen objects in the vicinity of the upper airways were segmented in these images and a total of 159 measurements were derived from each subject image which included object size, surface area, volume, sphericity, standardized T2-weighted image intensity value, and inter-object distances. A small set of discriminating features was identified from this set in several steps. First, a subset of measures that have a low level of correlation among the measures was determined. A heat map visualization technique that allows grouping of parameters based on correlations among them was used for this purpose. Then, through T-tests, another subset of measures which are capable of separating the two groups was identified. The intersection of these subsets yielded the final feature set. The accuracy of these features to perform classification of unseen images into the two patient groups was tested by using logistic regression and multi-fold cross validation.

Results

A set of 16 features identified with low inter-feature correlation (< 0.36) yielded a high classification accuracy of 96% with sensitivity and specificity of 97.8% and 94.4%, respectively. In addition to the previously observed increase in linear size, surface area, and volume of adenoid, tonsils, and fat pad in OSAS, the following new markers have been found. Standardized T2-weighted image intensities differed between the two groups for the entire neck body region, pharynx, and nasopharynx, possibly indicating changes in object tissue characteristics. Fat pad and oropharynx become less round or more complex in shape in OSAS. Fat pad and tongue move closer in OSAS, and so also oropharynx and tonsils and fat pad and tonsils. In contrast, fat pad and oropharynx move farther apart from the skin object.

Conclusions

The study has found several new anatomic bio-markers of OSAS. Changes in standardized T2-weighted image intensities in objects may imply that intrinsic tissue composition undergoes changes in OSAS. The results on inter-object distances imply that treatment methods should respect the relationships that exist among objects and not just their size. The proposed method of analysis may lead to an improved understanding of the mechanisms underlying OSAS.