Enhancing Parathyroid Gland Visualization Using a Near Infrared Fluorescence-Based Overlay Imaging System.

Area of Science:

• Medical Imaging
• Surgical Technology
• Biophotonics

Background:

• Misidentification of parathyroid glands (PGs) during thyroid surgery increases patient morbidity.
• Current near-infrared autofluorescence (NIRAF) imaging systems display PGs on remote monitors, lacking direct surgical field integration.
• This limitation hinders real-time spatial context and comparability with the actual surgical view.

Purpose of the Study:

• To design and evaluate an Overlay Tissue Imaging System (OTIS) for direct, real-time parathyroid gland visualization.
• To overcome the limitations of remote display monitors in existing NIRAF imaging systems.
• To enhance the accuracy of parathyroid localization during thyroidectomy and parathyroidectomy procedures.

Main Methods:

• The OTIS was calibrated using a fluorescent ink grid and tested ex vivo with various tissue types.
• In vivo studies involved projecting visible light directly onto suspected PGs based on detected NIRAF signals.
• System accuracy was validated by correlating projected images with surgeon confirmation and histopathology.

Main Results:

• The OTIS demonstrated 100% accuracy in ex vivo tissue testing.
• In vivo evaluation across 30 patients undergoing thyroid/parathyroid surgery showed 97% accuracy in visualizing parathyroid glands.
• The system provided label-free visualization directly in the surgical field without contrast agents.

Conclusions:

• The OTIS shows significant potential for improving label-free parathyroid gland visualization during surgery.
• Direct projection onto the surgical field enhances spatial awareness and comparability.
• Further optimization is necessary for widespread clinical adoption.