Low-dose phase contrast mammography with conventional x-ray sources

Area of Science:

• Medical Imaging
• Biomedical Engineering
• Radiology

Background:

• X-ray phase contrast imaging (XPCI) offers superior soft-tissue contrast compared to conventional radiography.
• Translating XPCI from synchrotron facilities to conventional X-ray sources faces challenges like limited field of view, stability, exposure time, and radiation dose.
• Existing XPCI methods adapted for conventional sources often require trade-offs between image quality and delivered dose.

Purpose of the Study:

• To develop and validate an X-ray phase contrast imaging (XPCI) method suitable for conventional X-ray sources.
• To improve XPCI performance by reducing radiation dose without compromising phase sensitivity.
• To facilitate the clinical translation of advanced XPCI techniques for mammography.

Main Methods:

• Adapted the "edge-illumination" XPCI technique for conventional X-ray sources using optimized X-ray masks.
• Modified mask design to minimize radiation dose to the sample.
• Built and tested a prototype system with ex vivo human breast tissue samples.

Main Results:

• The prototype demonstrated significant improvements in image quality for mammography applications.
• Microcalcification detection was enhanced, with contrast increases of 5-9 fold compared to conventional imaging.
• Features invisible in conventional images were detected, including microcalcifications.
• Radiation dose measurements confirmed compatibility with clinical practice standards.

Conclusions:

• Phase-enhanced imaging was successfully achieved in mammography using a system with off-the-shelf components.
• The developed XPCI method operates under clinically feasible exposure time and dose conditions.
• This work paves the way for the straightforward clinical implementation of phase-enhanced imaging techniques.