Diffuse Reflectance Spectroscopy for Surface Measurement of Liver Pathology

Area of Science:

• Medical instrumentation
• Optical spectroscopy
• Hepatology

Background:

• Liver parenchymal injuries like steatosis and fibrosis can complicate liver resection.
• Diffuse reflectance spectroscopy (DRS) is a rapid optical technique.
• Traditional DRS liver application requires invasive needle insertion.

Purpose of the Study:

• To evaluate a non-invasive, hand-held DRS probe for liver surface measurements.
• To determine the impact of the liver capsule on DRS readings.
• To assess if surface DRS measurements represent the whole liver and can differentiate tumor from parenchyma.

Main Methods:

• Developed a DRS system with a hand-held probe.
• Performed measurements on excised liver tissue with and without the capsule, and on cut surfaces.
• Applied an analytical model to estimate scattering parameters and chromophore fractions (blood, bile, fat).

Main Results:

• Analyzed 960 DRS spectra from 18 patients; tumor vs. liver tissue showed significant differences.
• Measured through the capsule: blood 8.4%, lipid 9.9%, bile 8.2%.
• No significant differences between surface and cross-section measurements; minimal differences with/without the capsule.

Conclusions:

• DRS measurements are feasible through the liver capsule.
• Surface DRS measurements are representative of the entire liver.
• Encourages in vivo studies for quantifying liver composition and assessing damage like steatosis and fibrosis.