Fluorescent thyroid imaging. Physical evaluation of an alternative instrument

Area of Science:

• Medical physics
• Nuclear medicine
• Diagnostic imaging

Background:

• Thyroid imaging often relies on radionuclide sources.
• Alternative methods for assessing intrinsic iodine are needed.
• X-ray fluorescence offers a potential non-radioactive approach.

Purpose of the Study:

• To develop and evaluate a rectilinear scanner for thyroid intrinsic iodine measurement.
• To assess the performance of an x-ray tube and Si(Li) detector system.
• To determine optimal operational parameters for thyroid scanning.

Main Methods:

• A rectilinear scanner-head assembly with an x-ray tube and Si(Li) detector was designed.
• The system was optimized for stimulating and detecting iodine fluorescence.
• Operational parameters including scanning distance and exposure settings were evaluated.

Main Results:

• A scanning distance of 3 inches (7.62 cm) was feasible due to high photon flux.
• The system achieved a full width at half maximum of 0.52 cm at 3 inches.
• Optimal exposure parameters were identified as 80 kVp, 0.5 mA with a copper-aluminum filter.

Conclusions:

• The developed rectilinear scanner is a practical alternative to radionuclide-based imaging.
• The system effectively stimulates and detects intrinsic iodine fluorescence in the thyroid.
• This technology offers a promising non-radioactive method for thyroid imaging.