Structured light imaging mesoscopy: application to skin changes in scleroderma.

Area of Science:

• Biomedical Optics
• Dermatology
• Medical Imaging

Background:

• Scleroderma is an autoimmune disease causing skin and organ fibrosis.
• Skin fibrosis extent predicts scleroderma severity and mortality.
• Current monitoring methods may lack objectivity and quantitative precision.

Purpose of the Study:

• To evaluate Structured Light Imaging Mesoscopy (SLIM) as a novel optical technique for assessing skin involvement in scleroderma.
• To determine optimal SLIM imaging parameters for scleroderma detection and monitoring.

Main Methods:

• SLIM measurements were acquired from 25 scleroderma patients and 18 healthy controls.
• A range of spatial frequencies and wavelengths were tested to identify optimal parameters across different skin tones.
• Monte Carlo simulations were performed using a multilayer skin model reflecting scleroderma-induced changes.

Main Results:

• Optimal SLIM parameters for scleroderma monitoring were identified as spatial frequency (fx) of 0.15–0.2 mm⁻¹ and wavelength (λ) of 811–851 nm, independent of skin tone.
• SLIM measurements using these parameters achieved an area under the curve (AUC) of ≥0.87 in discriminating scleroderma from healthy skin.
• Simulations suggest these findings correlate with alterations in dermal collagen.

Conclusions:

• SLIM provides a quantitative and objective method for evaluating skin involvement in scleroderma.
• The identified optimal imaging parameters target specific skin depths, enhancing sensitivity to scleroderma-related biological changes.
• SLIM holds potential for improved disease diagnosis and monitoring in scleroderma management.