Measurements of normal nasal airway assessed by 3-dimensional computed tomography in Chinese children and adolescents

Dynamical Changes of Mandible and Upper Airway After Mandibular Distraction Osteogenesis in Pierre Robin Sequence

OBJECTIVE

To present the dynamical evaluation of mandible and upper airway size among Chinese infant patients following mandibular distraction osteogenesis in a short-term follow-up and compare predistraction measurements with a normal age- and sex-matched control.

METHODS

All the patients have undergone the computed tomography (CT) scan before mandibular distraction osteogenesis (T0), at the end of the distraction phase (T1), and 3 months after the end of the distraction phase before the distractor removal (T2). A CT analyzing computer software MIMICS was utilized to analyze the anatomic variables of upper airway size and mandible size. All analysis was based on a significance level of 0.05.

RESULTS

Eight patients with Pierre Robin sequence differed mainly in the mandibular body length and the minimum anteroposterior dimension of the retroglossal airway from the control. After mandibular distraction osteogenesis, the mandibular body length and the ramus height both increased significantly, the ramus height also increased after 3 months of consolidation. Only small increase in the airway dimension of the retroglossal area at T2 was observed compared with T1.

CONCLUSION

Mandibular distraction osteogenesis is an effective modality in treating Pierre Robin sequence. Compared with normal control, the main difference may be the length of mandibular body and the area of the retroglossal airway. There may not be an increase in the diameter of airway and the length of mandibular body after 3 months of growth and development in Pierre Robin sequence. Individual surgical plan should be made to gain a better prognosis.

Endonasal measurements by acoustic rhinometry in children: A preliminary study

The acoustic reflection method (ARM) is a non-invasive technique which uses the reflection of acoustic waves to measure the cross sectional area of nasal cavities in adults and patency of endotracheal tubes. Characteristics and volume of normal nasal cavities in pre-school children has so far not been studied.

OBJECTIVE

The aim of this study was to determine the optimal ARM recording and the minimal cross-sectional area (MCA) and volume (NV) values in healthy children.

DESIGN

Prospective monocentric study using the ARM in pre-school children (<6 years of age).

RESULTS - DISCUSSION

Seventy children (age 2 to 5) were included in the study. Reliable measures were difficult to obtain in children younger than 2 years of age. The use of a standard nosepiece and a single-use surgical filter enabled reliable, serial recordings. Mean MCA values were 0.46, 0.53 and 0.58 cm² in the 24-35, 36-47 and 48-60 months-old age groups, respectively. Mean NV values were 2.14, 2.59, and 2.86 cm³ in the same age groups. The MCA and NV values were significantly correlated with height, age and weight. In conclusion, the ARM is feasible in children over the age of 2 and seems to be a promising non-invasive tool to study the nasal cavity patency, anatomy, and volume.

Gender-related difference in the upper airway dimensions and hyoid bone position in Chinese Han children and adolescents aged 6-18 years using cone beam computed tomography

OBJECTIVE

To investigate the gender-related differences in upper airway dimensions and hyoid bone position in Chinese Han children and adolescents (6-18 years) using cone-beam computed tomography (CBCT).

MATERIALS AND METHODS

CBCT-scans of 119 boys and 135 girls were selected and divided into four groups (group 1: 6-9 years; group 2: 10-12 years; group 3: 13-15 years; group 4: 16-18 years). The airway dimensions including the cross-sectional area (CSA), anteroposterior (AP) and lateral (LAT) width, length (L), mean CSA and volume (VOL) of upper airway segmentations and hyoid bone position including 11 linear and three angular measurements were investigated using Materialism's interactive medical image control system (MIMICS) 16.01 software. Gender-related differences were analyzed by two independent sample t-tests.

RESULTS

No gender-related difference was found in values of the facial morphology, airway dimensions and hyoid bone position for group 1 (p > 0.05). The children and adolescents in groups 2, 3 and 4 showed significant gender-related differences in the measurement results of facial morphology, airway dimensions and hyoid bone positions (p < 0.05). What's more, the measurement values of boys were obviously larger than those of girls except some measurements in group 2.

CONCLUSIONS

The measurements of airway dimensions and hyoid bone positions have gender-related differences in children and adolescents aged 10-18 years. These results could be taken into consideration during orthodontic diagnosis and treatment.