Improved computed radiography image quality from a BaFl:Eu photostimulable phosphor plate

Area of Science:

• Medical Physics
• Materials Science
• Radiography Imaging

Background:

• Photostimulable phosphor (PSP) plates are crucial components in computed radiography (CR) systems.
• Advancements in PSP plate design aim to enhance image quality and diagnostic performance.
• Barium fluoro-halide (BaF(Br,I):Eu) phosphors are commonly used, but new materials are being explored.

Purpose of the Study:

• To evaluate the image quality of newly designed BaFI:Eu phosphor plates for CR systems.
• To compare the performance of BaFI:Eu plates against existing BaF(Br,I):Eu and BaFBr:Eu plates.
• To determine the impact of BaFI:Eu on key image quality metrics like modulation transfer function (MTF), Wiener spectra (WSN), and detective quantum efficiency (DQE).

Main Methods:

• Comparative analysis of PSP plates including BaFI:Eu, BaF(Br,I):Eu, and BaFBr:Eu.
• Evaluation of image quality parameters: presampling modulation transfer function (MTF), normalized Wiener spectra (WSN), and detective quantum efficiency (DQE).
• Measurement of x-ray attenuation coefficients at 60 KeV for different phosphor materials.

Main Results:

• The BaFI:Eu plate demonstrated higher detective quantum efficiency (DQE) compared to the best BaF(Br,I):Eu plate across tested spatial frequencies (0.5, 1.0, 2.0 cycles/mm).
• The improved DQE of BaFI:Eu is attributed to significantly lower normalized Wiener spectra (WSN), indicating reduced image noise.
• BaFI:Eu exhibits higher x-ray attenuation coefficients (27% higher at 60 KeV) due to its iodine halide content, contributing to better x-ray absorption.

Conclusions:

• BaFI:Eu phosphor plates represent a significant advancement in CR technology.
• These plates offer a promising pathway to lower image noise and enhance overall CR system image quality.
• The material's superior x-ray absorption properties contribute to its improved performance metrics.