Scanning K-edge subtraction (SKES) imaging with laser-compton x-ray sources

Area of Science:

• Medical Imaging
• X-ray Physics
• Radiological Technology

Background:

• K-edge subtraction (KES) imaging uses dual-energy x-rays to enhance contrast for identifying contrast agent accumulation.
• Traditional KES requires tunable, quasimonoenergetic x-ray sources, often limited to synchrotrons.
• Laser-Compton x-ray sources (LCSs) offer a compact alternative but tuning their spectrum is time-consuming for clinical KES.

Purpose of the Study:

• Introduce scanning K-edge subtraction (SKES) for mammography using angle-correlated LCS x-ray spectra.
• Evaluate the feasibility and utility of SKES through simulation studies.
• Enable rapid KES imaging with LCSs without extensive spectral tuning.

Main Methods:

• Model Laser-Compton interaction physics using an X-band linear accelerator architecture.
• Propagate x-ray beams through digital breast phantoms with iodine contrast using Monte Carlo software.
• Compare SKES to direct energy tuning (DET) and conventional dual-energy contrast-enhanced mammography (CEM).

Main Results:

• Scanning KES (SKES) generated KES images comparable in quality to the direct energy tuning method.
• SKES detected tumors with lower iodine concentrations than currently possible, including those obscured by dense tissue.
• SKES achieved equal contrast to CEM at only 3% of the mean glandular dose.

Conclusions:

• SKES leverages LCSs' unique x-ray spectrum for enhanced contrast and reduced dose in KES imaging.
• The technique improves tumor detection in dense breast tissue compared to conventional systems.
• The scanning configuration of SKES can accelerate its clinical translation.