Dermatologic Scar Assessment With Stereoscopic Imaging and Digital Three-Dimensional Models: A Validation Study.

Area of Science:

• Medical imaging
• Biomedical engineering
• Dermatology

Background:

• Scar assessment traditionally relies on subjective visual evaluation or manual measurements.
• Objective, quantitative scar assessment is crucial for treatment efficacy and research.
• Existing methods may lack precision, repeatability, or 3D visualization capabilities.

Purpose of the Study:

• To evaluate a novel handheld stereoscopic imaging system for scar visualization.
• To validate the accuracy and repeatability of morphometric scar measurements using this system.
• To assess both intra- and inter-investigator variability in scar assessment.

Main Methods:

• Utilized engineered metal plates with model scars (n=72) and in vivo scars (n=15).
• Scanned model scars six times by one investigator; in vivo scars once by three investigators.
• Assessed repeatability using coefficients of variation (CVs) and compared digital 3D estimates to known/measured dimensions.

Main Results:

• Intra-investigator scans of model scars showed high repeatability (CV: 1.8-3.1%) for volume, area, length, and depth.
• Inter-investigator scans of in vivo scars had slightly higher CVs (4.4-7.3%), with variations linked to respiratory movement.
• Digital 3D scar estimates strongly correlated with physical dimensions (P<0.001) and ruler measurements (P<0.001).

Conclusions:

• Handheld stereoscopic imaging provides accurate and repeatable scar morphometric estimates.
• Minimal intra- and inter-investigator variation was observed, enhancing objective scar assessment.
• Minimizing patient movement is key to optimizing measurement accuracy, especially for in vivo applications.