X-Ray Phase Contrast Imaging Concepts and Systems

National Heart, Lung, And Blood Institute

Investigators

Linked publications & trials

Abstract

Introduction: My group is focused on the development of X-Ray imaging techniques for clinical and research applications. In the US 72% of medical imaging procedures involve X-rays such as radiography, angiography, CT and image guided interventional procedures. We tackle two major challenges shared by these modalities, which are the lack of tissue specificity and the concern of ionizing radiation exposure. We take advantage of the wave nature of x-rays to add two new dimensions to the image contrast. These are wave scattering and refractive bending. Wave scattering reveals microscopic structures which is independent from the conventional attenuation contrast. Materials that are indistinguishable by x-ray attenuation can be separated in the scattering dimension, similar to the benefit of 2D versus 1D gel electrophoresis. Refractive bending, or phase contrast, offers the potential of significant dose reduction since it arises from the refractive index variations in the body and does not require energy absorption. The wave nature of x-ray also opens avenues for shaping the x-ray beam with advanced optics in ways that enhance resolution and reduce dose exposure to the subject. Our accomplishments: We have discovered a new optics phenomenon which lead to a new type of x-ray and neutron interferometer. An interferometer is a device that can be used to measure or image the wave characteristics of a light or matter beam. Future plan: We entered into collaboration with the Walter Reed Medical Center Breast Imaging Center and Dr. Robert Lederman's lab in NHLBI to explore clinical applications of the technologies we created in our lab.