Open-Source Tools for Dense Facial Tissue Depth Mapping of Computed Tomography Models

Area of Science:

• Anthropology
• Forensic Science
• Medical Imaging

Background:

• Computed tomography (CT) scans offer a valuable resource for generating 3D digital skeletal data.
• Simultaneous visualization of bone and skin in 3D digital environments enhances facial approximation techniques.
• Quantifying craniofacial relationships can be achieved through landmarks or surface-processing software.

Purpose of the Study:

• To describe tools for generating dense facial tissue depth maps (FTDMs) from deidentified head CT scans.
• To utilize open-source software for processing and analyzing 3D facial data.
• To create standardized reference collections for anthropological and forensic studies.

Main Methods:

• Deidentified head CT scans were segmented to create 3D skull and face models.
• Models were processed in Meshlab, transformed to a common orientation, and cropped.
• Dense FTDMs were generated using the Hausdorff sampling filter and colorized based on depth values.

Main Results:

• 112 FTDMs were generated for 106 individuals, with minimum depths ranging from 1.2 mm to 3.4 mm.
• Common minimum depths were observed over nasal bones, lateral orbital margins, and forehead.
• Maximum depths were found in the buccal region and neck; weight variations impacted these areas more than thin areas.

Conclusions:

• The study produced visual, quantitative 3D facial and skull representations for forensic facial approximation.
• The developed tools are applicable to various CT scan types and individuals, regardless of orientation.
• This method provides replicable data outputs readable with openly accessible software for facial variation and growth studies.