Using three-dimensional geometric morphometry for facial analysis in patients with the oculo-auriculo-vertebral...

Area of Science:

• Craniofacial Surgery
• Medical Imaging
• Biomedical Engineering

Background:

• Oculo-auriculo-vertebral spectrum (OAVS) is a congenital disorder characterized by craniofacial abnormalities.
• Facial asymmetry is a common and significant feature in OAVS patients, impacting both aesthetics and function.
• Objective quantification of facial asymmetry is crucial for diagnosis, treatment planning, and monitoring disease progression.

Purpose of the Study:

• To apply three-dimensional (3D) geometric morphometry for visualizing and quantifying facial asymmetry in patients with OAVS.
• To assess the utility of 3D geometric morphometry as an objective tool for evaluating facial asymmetry in OAVS.
• To analyze changes in facial asymmetry over time using 3D facial scans.

Main Methods:

• Acquired 3D facial scans from 25 Czech patients diagnosed with OAVS.
• Classified patients into subgroups based on the Pruzansky classification.
• Utilized geometric morphometry on 3D facial scans to analyze soft tissue asymmetry in the sagittal plane.
• Employed color-coded maps with a thermometre-like scale to visualize asymmetry and its temporal changes.

Main Results:

• Individual and mean facial asymmetry were visualized for all patients and Pruzansky subgroups.
• No significant differences in asymmetry were observed between type I and type IIA subgroups.
• Increased asymmetry was noted between type IIA and IIB (up to 1.5 mm) and between type IIB and III (up to 2 mm) in the middle and lower facial thirds.
• The intensity of asymmetry in the affected facial thirds remained relatively stable over the two time points observed.

Conclusions:

• Three-dimensional geometric morphometry is a valuable tool for the objective assessment of facial asymmetry in OAVS patients.
• The generated color-coded maps offer illustrative and clinically useful insights into facial asymmetry.
• This technique aids in understanding the patterns and progression of facial asymmetry in OAVS, supporting clinical decision-making.