Real-time assessment of liver fat content using a filter-based Raman system operating under ambient light through...

Area of Science:

• Biomedical Engineering
• Medical Diagnostics
• Spectroscopy

Background:

• Accurate assessment of liver steatosis is crucial for organ transplantation.
• Current visual inspection methods by surgeons are subjective and prone to misclassification.
• Objective, real-time tools are needed to improve liver fat content assessment during procurement.

Purpose of the Study:

• To develop and validate a handheld Raman spectroscopy system for real-time, objective assessment of liver fat content.
• To evaluate the system's performance in various lighting conditions and tissue depths.
• To establish the correlation between Raman signal intensity and calibrated liver fat content.

Main Methods:

• A Raman system utilizing a 1064 nm laser, handheld probe, optical filters, photodiodes, and a lock-in amplifier was developed.
• The system was tested on duck fat phantoms and duck liver samples under varying ambient light conditions.
• Light penetration depth was assessed, and signal intensity was correlated with Magnetic Resonance Imaging (MRI)-calibrated fat content.

Main Results:

• The Raman system demonstrated consistent performance in both normal and strong ambient light.
• Excitation light successfully penetrated at least 1 mm into phantoms and liver samples.
• A linear correlation was observed between the system's signal intensity and MRI-calibrated liver fat content.

Conclusions:

• The developed Raman spectroscopy system provides a reliable and objective method for real-time liver fat content assessment.
• This technology has the potential to significantly improve the accuracy of liver assessment during procurement, reducing misclassification errors.
• The system's ability to perform under diverse lighting and penetrate tissue depths makes it a promising tool for clinical application.