Dose-compatible grating-based phase-contrast mammography on mastectomy specimens using a compact synchrotron source

Elena Eggl,Doris Mayr,Christoph Jud,Maximilian F Reiser,Jan J Wilkens,Anikό Sztrόkay-Gaul,Julia Herzen,Franz Pfeiffer,Karin Hellerhoff,Martin Dierolf,Lisa Heck,Susanne Grandl,Bernhard Gleich,Karin Burger,Klaus Achterhold,Sigrid D Auweter,Benedikt Günther

doi:10.1038/s41598-018-33628-z

Abstract

With the introduction of screening mammography, the mortality rate of breast cancer has been reduced throughout the last decades. However, many women undergo unnecessary subsequent examinations due to inconclusive diagnoses from mammography. Two pathways appear especially promising to reduce the number of false-positive diagnoses. In a clinical study, mammography using synchrotron radiation was able to clarify the diagnosis in the majority of inconclusive cases. The second highly valued approach focuses on the application of phase-sensitive techniques such as grating-based phase-contrast and dark-field imaging. Feasibility studies have demonstrated a promising enhancement of diagnostic content, but suffer from dose concerns. Here we present dose-compatible grating-based phase-contrast and dark-field images as well as conventional absorption images acquired with monochromatic x-rays from a compact synchrotron source based on inverse Compton scattering. Images of freshly dissected mastectomy specimens show improved diagnostic content over ex-vivo clinical mammography images at lower or equal dose. We demonstrate increased contrast-to-noise ratio for monochromatic over clinical images for a well-defined phantom. Compact synchrotron sources could potentially serve as a clinical second level examination.

Highlights

Mammography is an invaluable clinical tool for the early detection of breast cancer
Four freshly dissected mastectomy specimens and a mammographic accreditation phantom were investigated with ex-vivo clinical mammography and both conventional absorption and grating-based multimodal monochromatic experimental mammography
The applied mean glandular dose (MGD) and the exposure times are given in Table 4 for each sample and imaging modality

Summary

Introduction

Mammography is an invaluable clinical tool for the early detection of breast cancer. the inherently low contrast in absorption x-ray imaging for soft tissue compromises the diagnostic performance, especially in the case of dense breasts. In order to combine the advantages and avoid some disadvantages of the two approaches, we suggest to perform grating-based multimodal mammography at a compact synchrotron source based on inverse Compton scattering. These recently developed x-ray sources are compact enough to fit into regular laboratories[21]. They offer a monochromatic x-ray beam that is tunable in energy and partially coherent, allowing to obtain increased diagnostic content from grating-based phase-contrast and dark-field images while achieving equal image quality at lower dose compared to the aforementioned laboratory setups. The Munich Compact Light Source (MuCLS, Lyncean Technologies, USA) is the first commercial installation of an inverse Compton compact synchrotron source[22]

Methods

Results

Conclusion