Simple beam hardening correction method (2DCalBH) based on 2D linearization.

Area of Science:

• Medical Imaging
• Physics

Background:

• Computed tomography (CT) imaging is susceptible to beam hardening artifacts due to the polychromatic nature of X-ray beams.
• These artifacts, including cupping and dark bands, lead to inaccurate quantitative values in reconstructed images.
• Existing correction methods often require knowledge of the X-ray spectrum or suboptimal parameter selection.

Purpose of the Study:

• To develop and validate a novel post-processing method for correcting beam hardening artifacts in CT images.
• To restore the quantitative accuracy of CT images without requiring X-ray spectrum information or heuristic parameter tuning.
• To improve image quality and diagnostic reliability in heterogeneous imaging studies.

Main Methods:

• The proposed method extends the water-linearization technique using a simple calibration phantom.
• It characterizes X-ray beam attenuation for soft tissue and bone combinations.
• Correction is based on bone thickness derived from a preliminary reconstruction, validated with simulations and real phantom data (PMMA and aluminum 6082).

Main Results:

• Simulated data demonstrated artifact correction and monochromatic value recovery comparable to existing methods.
• The proposed method significantly outperformed existing techniques on real CT data.
• The approach successfully restored quantitative accuracy in the presence of beam hardening artifacts.

Conclusions:

• The developed method effectively corrects beam hardening artifacts in CT imaging.
• It restores monochromatic attenuation values without spectrum knowledge or parameter tuning.
• This approach offers a robust and simpler solution for quantitative CT imaging.