Dual Energy Differential Phase Contrast CT (DE-DPC-CT) Imaging

Area of Science:

• Medical Imaging
• Materials Science
• Physics

Background:

• Current dual-energy CT (DECT) struggles with accurate material quantification when more than two elements are present.
• Accurate material decomposition is crucial for quantitative analysis in various imaging applications.

Purpose of the Study:

• To develop and validate an innovative three-material decomposition scheme using dual-energy differential phase contrast CT (DE-DPC-CT).
• To enhance the accuracy and robustness of elemental material quantification in CT imaging.

Main Methods:

• A DE-DPC-CT system was engineered utilizing a grating interferometer and a dual-energy photon-counting CT scanner.
• The system simultaneously measures the real and imaginary parts of the complex refractive index.
• Physical phantoms with 21 material inserts and biological tissues with iodine were employed for testing.

Main Results:

• The DE-DPC-CT method achieved high accuracy in elemental material quantification, with relative root-mean-square errors of 4.5% for calcium and 5.2% for iodine.
• The system successfully differentiated bony structures, iodine, and soft tissues in biological samples.
• Material decomposition using DE-DPC-CT exhibited significantly lower quantification noise compared to triple-spectra CT.

Conclusions:

• The proposed DE-DPC-CT scheme enables accurate three-material decomposition, overcoming limitations of conventional DECT.
• This method holds significant potential for advanced quantitative spectral CT imaging in biological and material science applications.
• DE-DPC-CT offers superior performance in terms of quantification noise reduction compared to existing multi-energy CT techniques.