Three-Dimensional Upper Airway Assessment in Treacher Collins Syndrome

Abstract

Objectives: The purpose of this investigation was to assess the pharyngeal dimensions and the craniofacial morphology of individuals with Treacher Collins syndrome (TCS) when compared to vertical skeletal class II individuals. It is our hypothesis that the upper airways of individuals with TCS are reduced in view of the skeletal pattern and the maxillomandibular dysmorphologies. Materials and Methods: Cone-beam computed tomography scans of 26 individuals had the pharyngeal volume (V) and minimal cross-sectional area (mCSA) evaluated. Study group (TCS) was formed by 13 scans of patients with TCS (7 males and 6 females; 20.2 ± 4.7 years). Control group (CG) assembled 13 scans of nonaffected individuals with the same type of skeletal pattern (2 males and 11 females; 26.6 ± 5.4 years). Cephalometric data of maxillomandibular position, maxillomandibular dimensions, and growth pattern were assessed. Statistical analysis ( P ≤ .05) included Student t test and Pearson correlation coefficient. Results: Although reduced, pharyngeal V and mCSA of TCS were not statistically different from the CG. On both groups, mCSA was mostly at the oropharyngeal level. Individuals with TCS presented retrognathic chin, reduced maxillomandibular dimensions, and increased clockwise rotation of the palatal plane. Maxillary and mandibular lengths were correlated with pharyngeal V and mCSA. Conclusions: The pharyngeal dimensions of individuals with TCS are impacted by the micrognathia and retrognathia. In association with the skeletal pattern, the reduction of the airways, although not statistically significant, may explain the increased prevalence of airways disorder in this syndrome.

Modern views on anthropometric variability of the upper airway (literature review)

“…In the case of Treacher Collins syndrome, even despite the presence of micrognathia and retrognathia in such patients, no statistically significant difference in UA compared to healthy individuals was found [26].…”

A systematic review on Treacher Collins syndrome: Correlation between molecular genetic findings and clinical severity

“…In line, our preliminary analysis also revealed that maxillary and mandibular projections were significantly altered in TCS individuals (data not shown), which may contribute to the development of airway obstruction secondary to abnormal bony morphology. It has been reported that around 46% of TCS individuals experienced some degree of airway obstruction, 61,62 ranging from mild obliteration to severe and life‐threatening obstructive sleep apnea 63 . Esenlik et al 64 described that increased mandibular retrognathia, decreased posterior facial height, wider maxillary/mandibular plane angle, and wider symphysis notch angle are strongly correlated with TCS severity.…”

An Approach to the Airway Management in Children with Craniofacial Anomalies

“…Airway and anesthetic implications: Treacher Collins syndrome (TCS) was firstly reported as a hazard for general anesthesia in 1963 by Edward Ross due to the difficulty in maintaining a free and adequate airway. Several associated mechanisms are the cause, namely mandibular hypoplasia, micrognathia, retrognathia, posterior displacement of the bulky tongue, and the pharyngeal hypoplasia, resulting in a small and narrow retromandibular space [29,30]. The presence of a temporomandibular joint abnormality or a small mouth aperture may further worsen the case.…”