X-ray phase-contrast tomosynthesis for improved breast tissue discrimination

Area of Science:

• Medical Imaging
• Biophysics
• Radiology

Background:

• Mammography struggles with glandular tissue overlap, limiting differentiation between tumorous and healthy breast tissue.
• Tomosynthesis improves depth resolution but still faces challenges in distinguishing subtle tissue differences based on X-ray attenuation.
• Grating-based phase-contrast imaging offers complementary data (phase shift, scattering) to enhance soft-tissue contrast.

Observation:

• A mastectomy sample with invasive ductal carcinoma was imaged using grating-based phase-contrast tomosynthesis.
• The study utilized a synchrotron X-ray source with a two-grating interferometer setup, capturing absorption, differential phase, and scattering data.
• Tomographic reconstruction was performed using filtered back-projection, with results compared to histopathology.

Findings:

• Phase-contrast tomosynthesis significantly enhances soft tissue contrast compared to conventional absorption methods.
• Improved feature visibility in phase-contrast tomosynthesis overcomes superposition artifacts inherent in 2D imaging.
• Depth resolution in tomosynthesis slices clearly depicts regions like necrotic tissue, which are obscured in projection images.

Implications:

• This study presents the first proof-of-principle for grating-based phase-contrast tomosynthesis on a mastectomy sample.
• Combining phase-contrast and dark-field signals with conventional attenuation increases diagnostic value, verified by histological comparison.
• The success of grating-based phase-contrast mammography with lab sources suggests phase-contrast tomosynthesis could be translated to clinical settings.