Cone-Beam Computed Tomography Analysis of the Nasopharyngeal Airway in Nonsyndromic Cleft Lip and Palate Subjects

Comparison of Nasopharyngeal Airway Volume in Cleft Lip and Palate Patients With Normal Individuals Using Cone Beam Computed Tomography

This study aimed to compare nasopharyngeal airway volume in cleft lip and palate patients with normal individuals using Cone Beam Computed Tomography (CBCT). In this cross-sectional study, 40 CBCT scans of 9 to 12-years-old patients were enrolled and divided into 3 groups: normal individuals (n=16), unilateral cleft lip and palate (UCLP, n=14) and bilateral cleft lip and palate patients (BCLP, n=10). Superior and middle pharyngeal airway volumes and nasal width were measured and compared between 3 groups. ANOVA and χ 2 tests were used for statistical comparison. P <0.05 was considered significant. Superior airway volume was not significantly different between the 3 groups ( P =0.36). However, there was a significant difference between the 3 groups regarding middle pharyngeal volume ( P =0.49) and nasal width ( P =0.021). There was not a significant difference in the upper and middle pharyngeal volume and also nasal width between the 2 sexes. Considering different dimensions of evaluation of the pharyngeal airway volume of cleft lip and palate patients, the evaluation of airway volume is essential during orthodontic or orthognathic surgical treatments that expand or protect the maxilla.

Three-dimensional assessment of airway volumes in patients with unilateral cleft lip and palate

Background

Considering the adverse consequences of respiratory insufficiency in cleft lip and palate (CLP) patients, this study aimed to assess the pharyngeal airway dimensions in 9–12-year-old patients with unilateral CLP. This historical cohort evaluated the cone-beam computed tomography (CBCT) scans of 30 patients with non-syndromic unilateral CLP between 9 and 12 years and 30 age- and sex-matched non-cleft controls. Three-dimensional (3D) images were reconstructed by the Mimics software, and the nasopharyngeal, oropharyngeal, and total airway volumes, as well as the minimal cross-sectional area of the airway (minAx), and posterior airway length (PAL) were all measured in the sagittal plane. Data were analyzed by the Student’s t test.

Results

The oropharyngeal and the total airway volumes, as well as the minAx and PAL in CLP patients, were significantly smaller than the corresponding values in the control group (P < 0.05). Despite smaller nasopharyngeal airway volume in CLP patients than controls, this difference was not statistically significant (P > 0.05).

Conclusions

Nine- to twelve-year-old non-syndromic unilateral CLP patients have smaller pharyngeal airway dimensions than non-cleft controls, and are therefore at higher risk of respiratory insufficiency.

Internal nasal dimensions of children with unilateral cleft lip and palate and maxillary atresia: comparison between acoustic rhinometry technique and cone-beam computed tomography

PURPOSE

To compare the nasal cavity geometry of children and teenagers with cleft lip and palate and maxillary atresia by two methods: cone-beam computed tomography, considered the gold standard, and acoustic rhinometry.

METHODS

Data on cone-beam computed tomography and acoustic rhinometry examinations of 17 children and teenagers with cleft lip and palate and maxillary atresia, previously obtained for orthodontic planning purposes, were evaluated prospectively. Using Dolphin Imaging 11.8 software, the nasal cavity was reconstructed by two evaluators, and the internal nasal volumes were obtained. Using rhinometry, the volumes of regions V1 and V2 were measured. The values of each examination were then compared at a significance level of 5%.

RESULTS

Statistical analysis showed high intra- and inter-rater reproducibility in the cone-beam computed tomography analysis. The mean internal nasal volumes (± standard deviation) obtained using acoustic rhinometry and cone-beam computed tomography corresponded to 6.6 ± 1.9 cm3 and 8.1 ± 1.5 cm3, respectively. The difference between the examinations was 17.7%, which was considered statistically significant (p = 0.006).

CONCLUSION

The nasal volumes measured via the two methods were different; that is, they presented discrepancies in the measurements. The gold standard technique identified larger volumes than acoustic rhinometry in the nasal cavity. Therefore, determining which test reflects clinical reality is an essential future step.

Nasopharyngeal structure development in patients with cleft palate who underwent repair surgery

OBJECTIVE

This study aimed to compare the developmental characteristics of bony nasopharyngeal (NP) in children with cleft palate (CP) and non-cleft subjects.

METHODS

This study was conducted on 64 non-syndromic CP patients who underwent repair surgery and 23 non-cleft subjects as controls. Lateral cephalograms were performed on participants at rest in the natural head position. The X-coordinate and the Y-coordinate of three points on cephalograms were determined as Hormion (Ho), posterior maxillary point (PMP) and anterior point of the atlas (At) representing the anterior-posterior (AP) and vertical dimension of the NP. The linear dimension of the NP (i.e. Ho-At, Ho-PMP, At-PMP) and its area was also calculated.

RESULTS

The bony structures of NP in the clef-affected subjects in isolated CP subgroup, had a significantly greater downward development in the maxillary region (PMP) (both with p = 0.001), more linear growth in cranial-maxillary (Ho-PMP) dimension (p = 0.017 and 0.004, respectively), and larger area (p = 0.017 and <0.001, respectively), when compared to normal subjects. There was no significant difference between either the unilateral cleft lip and palate (CLP) or bilateral CLP group with the control group regarding AP, vertical, and linear growth of the NP and its area (P > 0.05).

CONCLUSIONS

Patients with repaired CP had downward deviated posterior maxilla, more linear growth in cranial-maxillary dimension and larger area compared to normal subjects. Among CP subtypes, a balanced growth was observed among repaired UCLP and BCLP patients, suggesting that with appropriate repaired surgery, normal development of the NP region could be expected in these subtypes.

Three-Dimensional Assessment of Pharyngeal Volume on Computed Tomography Scans: Applications to Anesthesiology and Endoscopy

Pharyngeal volume is important in anesthesiology for correctly assessing intubation procedures. However, most of studies are based on patients in upright position and do not assess possible relationships between pharyngeal volume and cranial size. This study aims at measuring pharyngeal volume in CT-scans and to assess possible statistically significant differences according to sex.Eighty healthy subjects (40 males and 40 females) aged between 21 and 86 years were retrospectively chosen from a hospital database of maxillofacial CT-scans; 3D segmentation was performed separately for naso-, oro- and laryngopharyngeal portion through ITK-SNAP software, and their volume was calculated. Three cranial measurements were obtained: distance between anterior and posterior nasal spine, upper facial height (nasion-prosthion) and biorbital breadth (ectoconchion-ectoconchion distance).The effect of sex on volume for each pharyngeal portion was assessed through one-way ANCOVA test using each of the 3 cranial measurements as covariate (P < 0.05).On average, the volume of nasopharynx, oropharynx and laryngopharynx was 7.2 ± 2.7 cm, 7.5 ± 4.2 cm, 3.5 ± 2.2 cm respectively in males, and 6.4 ± 2.9 cm, 5.2 ± 2.1 cm, 3.0 ± 1.8 cm in females. Statistically significant differences according to sex were found only for oropharyngeal volume, independently from cranial measurements (P < 0.05).This study provides data concerning volume of pharyngeal air space in supine subjects: these reference standards can be useful for anaesthesiologic procedures.

Cone-Beam Computed Tomography Evaluation of Skeletal Deformities and Pharyngeal Airway in Chinese Han Individuals With Nonsyndromic Unilateral Cleft Lip and Palate

Objective:

This study examined the relationships between skeletal deformities and the pharyngeal airway of patients with nonsyndromic unilateral cleft lip and palate (UCLP).

Design:

Retrospective study.

Setting:

Orthodontics and Oral and Maxillofacial Surgery Departments in the Affiliated Hospital of Stomatology, Nanjing Medical University, China.

Patients, Participants:

The sample comprised 30 nonsyndromic UCLP patients and 30 healthy controls. Each group has 23 males and 7 females.

Interventions:

All cone-beam computed tomography images were obtained with the participant in the standard supine position and asked to bite with intercuspal position without swallowing or moving their heads and tongues during scanning.

Main Outcome Measure(s):

SNA, SNB, ANB, anterior cranial base, Wits appraisal, maxillary length (PTM-ANS || FH), maxillary position (S-PTM || FH), mandibular length (Go-Pog || MP), FMA, posterior face height, anterior face height, Posterior-Anterior face height, lower face height, pharyngeal airway volumes, and areas were evaluated by Dolphin imaging software.

Results:

The UCLP group showed significantly decreased SNA, SNB, ANB, PTM-ANS || FH, S-PTM || FH, P-A Face Height compared with the controls. However, the airway volumes and areas showed no significant difference between 2 groups. The total airway volume and minimum cross-sectional area in UCLP patients were related to the Go-Pog || MP and FMA.

Conclusions:

Patients with UCLP have both the maxillary and mandibular deficiencies in the sagittal dimension. Both the sagittal and vertical relationships of the jaw might affect the airway volume and area. However, no significant difference was detected in airway volume and area in UCLP patients when compared with the controls.

Three-dimensional assessment of the pharyngeal airway in Japanese preschoolers with orofacial clefts

OBJECTIVES/HYPOTHESIS

Individuals with orofacial clefts often experience respiratory problems because of nasopharyngeal abnormalities. Pharyngeal airway morphology is thought to differ among the various cleft types. We measured three-dimensional (3D) airway volume using cone-beam computed tomography (CBCT) analysis to evaluate and compare pharyngeal airways in Japanese preschoolers with and without orofacial clefts.

STUDY DESIGN

Retrospective case-control study.

METHODS

We enrolled 83 subjects (37 boys, 46 girls; mean age = 4.66 ± 0.56 years) with nonsyndromic orofacial clefts and 16 noncleft healthy subjects (seven boys, nine girls; mean age = 5.30 ± 0.52 years) as controls. The subjects were divided into five groups. Four groups were based on the cleft type: isolated cleft palate, unilateral cleft lip and alveolus), unilateral cleft lip and palate, and bilateral cleft lip and palate. The fifth group included the noncleft controls. All subjects were examined with CBCT, and the 3D airway volume was measured. We analyzed group differences statistically using analysis of covariance with the Bonferroni post hoc pairwise comparison tests for the corrected means.

RESULTS

Compared with the noncleft group, each cleft group exhibited significantly decreased total and nasal airway volumes and increased superior and inferior pharyngeal airway volumes. The differences were all statistically significant.

CONCLUSIONS

Our findings suggest that anatomical differences exist in pharyngeal airway volumes among various cleft groups and in those without a cleft.

LEVEL OF EVIDENCE

3b Laryngoscope, 130:533-540, 2020.