Moving to 3D: Quantifying Virtual Surgical Planning Accuracy Using Geometric Morphometrics and Cephalometrics in...

Area of Science:

• Plastic Surgery
• 3D Imaging
• Quantitative Analysis

Background:

• Facial feminization surgery (FFS) aims to feminize facial features in transgender women.
• Virtual surgical planning (VSP) is used to improve predictability in FFS.
• Quantifying shape changes in FFS is challenging due to multi-dimensional alterations.

Purpose of the Study:

• To apply cephalometric and geometric morphometric analyses to evaluate shape changes in FFS patients.
• To assess the accuracy of virtual surgical planning (VSP) in genioplasty and mandibular contouring.

Main Methods:

• 3D reconstructions from preoperative, postoperative, and VSP-guided scans of 14 FFS patients.
• Analysis using cephalometrics and geometric morphometrics (Generalized Procrustes Analysis).
• Comparison of postoperative scans with VSP-predicted shapes.

Main Results:

• Postoperative bigonial width significantly aligned with planned values.
• Geometric morphometrics confirmed significant alignment between postoperative and planned scans for specific procedures.
• Deviations from planned shapes were often intermediate between preoperative and planned states, possibly due to surgical modifications.

Conclusions:

• Virtual surgical planning (VSP) demonstrates high accuracy in predicting bony shape changes for genioplasty and mandibular contouring in FFS.
• Cephalometrics and geometric morphometrics are effective tools for quantifying FFS outcomes.
• Further research with more landmarks may enhance the evaluation of bony changes in FFS.