Diffuse Optical Characterization of the Healthy Human Thyroid Tissue and Two Pathological Case Studies.

Area of Science:

• Biomedical Optics
• Medical Physics
• Translational Medicine

Background:

• Non-invasive characterization of thyroid tissue hemodynamics is crucial for diagnosing conditions like thyroid cancer.
• Traditional methods for assessing thyroid tissue often require invasive procedures or lack detailed hemodynamic information.

Observation:

• A custom time-resolved spectroscopy (TRS) and diffuse correlation spectroscopy (DCS) system was employed for in vivo measurements.
• Medical ultrasound guided the placement of a hybrid optical probe for precise tissue targeting.
• TRS and DCS quantified absorption, scattering, total hemoglobin concentration (THC), oxygen saturation (StO2), and blood flow index (BFI).

Findings:

• Healthy thyroid tissue exhibited significantly higher total hemoglobin concentration (25-44% increase) and blood flow index compared to sternocleidomastoid muscle.
• Oxygen saturation showed a small but significant difference between thyroid and muscle tissue.
• Pathological thyroid nodules displayed markedly elevated THC (approx. 226.5 μM) and BFI (approx. 62.8 × 10-9 cm2/s), contrasting with healthy tissue.

Implications:

• These findings establish baseline optical and hemodynamic properties for healthy and pathological human thyroid tissue.
• The distinct hemodynamic signatures of thyroid nodules suggest diffuse optics could be a valuable tool for thyroid cancer screening.
• Further research using diffuse optics may lead to non-invasive diagnostic methods for thyroid pathologies.