Investigation of a solid-state detector for advanced computed tomography

Area of Science:

• Medical Physics
• Radiological Imaging Technology
• Detector Physics

Background:

• Solid-state detectors are crucial for computed tomography (CT) performance.
• Detector speed and afterglow are key parameters influencing CT image quality.
• Understanding signal decay characteristics is essential for optimizing detector performance.

Purpose of the Study:

• To investigate the signal decay characteristics of the HiLight scintillating detector.
• To model and characterize detector primary speed and afterglow using a multiexponential function.
• To analyze the impact of detector parameters on CT image quality and develop a correction scheme.

Main Methods:

• Modeling detector primary speed and afterglow with a multiexponential function.
• Analyzing parameter sensitivity to X-ray photon energy, detector aging, and radiation exposure.
• Utilizing computer simulations and phantom experiments to assess image quality impacts.
• Developing and validating an algorithmic correction scheme using a recursive filter.

Main Results:

• Detector primary speed and afterglow parameters showed no statistically significant variation with external variables.
• Simulations and experiments demonstrated the impact of decay time constants on spatial resolution, noise, and artifacts.
• The algorithmic correction scheme successfully restored spatial resolution and reduced noise.
• The correction scheme effectively eliminated ring-band artifacts caused by detector afterglow.

Conclusions:

• The HiLight detector's signal decay parameters are robust against variations in X-ray energy, aging, and exposure.
• An algorithmic correction scheme effectively compensates for detector afterglow, significantly improving CT image quality.
• The developed correction method is effective and robust, validated through extensive phantom and clinical experiments.