Contact, high-resolution spatial diffuse reflectance imaging system for skin condition diagnosis

Area of Science:

• Biomedical Optics
• Medical Imaging
• Spectroscopy

Background:

• Spatially resolved diffuse reflectance spectroscopy (srDRS) is crucial for noninvasive, in vivo tissue optical property characterization.
• Current srDRS systems face limitations in achieving depth-resolved analysis due to resolution challenges.
• Accurate tissue optical properties are vital for various clinical diagnostic applications.

Purpose of the Study:

• To introduce a compact, low-cost srDRS architecture for high-resolution, lensless diffuse reflectance imaging.
• To demonstrate the feasibility of this new system for quantitative characterization of tissue optical properties.
• To lay the groundwork for developing affordable, wearable devices for in vivo skin diagnostics.

Main Methods:

• Developed a prototype srDRS device using a multipixel imaging sensor and LEDs for lensless contact imaging.
• Employed a complementary metal-oxide semiconductor coupled with a fiber-optic plate.
• Acquired diffuse reflectance profiles at 645 nm with high spatial resolution (16.7 μm) and varying source-to-detector separations (480 μm to 4 mm).

Main Results:

• Successfully measured absorption coefficients (μa) with 4.2 ± 3.5% error and reduced scattering coefficients (μs') with 7.0 ± 4.6% error in homogeneous tissue phantoms.
• Demonstrated high spatial resolution in diffuse reflectance profiling.
• Validated the quantitative accuracy of the developed srDRS approach.

Conclusions:

• The novel srDRS architecture offers a promising, low-cost solution for in vivo tissue optical property measurement.
• The system's high spatial resolution and quantitative accuracy support its potential in clinical settings.
• This work represents a significant step towards wearable srDRS devices for accessible skin condition diagnosis.