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Carotid artery plaque instability can result in rupture and lead to ischaemic stroke. Stability of plaques appears to be a function of composition. Current non- invasive imaging techniques are limited in their ability to classify distinct histological regions within plaques. Phase-contrast (PC) X-ray imaging methods are an emerging class of techniques that have shown promise for identifying soft-tissue features without use of exogenous contrast agents. This is the first study to apply analyser-based X-ray PC imaging in CT mode to provide three-dimensional (3D) images of excised atherosclerotic plaques. The results provide proof of principle for this technique as a promising method for analysis of carotid plaque microstructure. Multiple image radiography CT (MIR-CT), a tomographic implementation of X-ray PC imaging that employs crystal optics, was employed to image excised carotid plaques. MIR-CT imaging yields three complementary images of the plaque's 3D X-ray absorption, refraction and scatter properties. These images were compared with histological sections of the tissue. X-ray PC images were able to identify the interface between the plaque and the medial wall. In addition, lipid-rich and highly vascularized regions were visible in the images as well as features depicting inflammation. This preliminary research shows MIR-CT imaging can reveal details about plaque structure not provided by traditional absorption-based X-ray imaging and appears to identify specific histological regions within plaques. This is the first study to apply analyser-based X-ray PC imaging to human carotid artery plaques to identify distinct soft-tissue regions. [ABSTRACT FROM AUTHOR]

Diffraction enhanced imaging (DEI), also called analyzer-based imaging (ABI), cultivated within the synchrotron community, has the potential to revolutionize medical imaging through reduced dose and enhanced contrast imaging. [ABSTRACT FROM AUTHOR]

We have developed a new X-ray imaging technique, diffraction enhanced imaging (DEI), which can be used to independently visualize the refraction and absorption of an object. The images are almost completely scatter-free, allowing enhanced contrast of objects that develop small angle scattering. The combination of these properties has resulted in images of mammography phantoms and tissues that have dramatically improved contrast over standard imaging techniques.This technique potentially is applicable to mammography and other fields of medical X-ray imaging and to radiology in general, as well as possible use in nondestructive testing and X-ray computed tomography. Images of various tissues and materials are presented to demonstrate the wide applicability of this technique to medical and biological imaging. [ABSTRACT FROM AUTHOR]

Abstract: Diffraction Enhanced Imaging (DEI) is an X-ray imaging method to provide additional contrast and diminish untoward image signals by reducing scattering. Previous reports demonstrated its applicability in soft and hard tissue imaging. Here we provide further evidence for the improved overall image quality and for the option to discriminate various tissue-specific properties, such as collagen fiber elements or mineralization. Comparative ex vivo data to medical MRI and to medical ultrasound are shown, utilizing human ankle and hip specimens. [Copyright &y& Elsevier]