Emphysema early diagnosis using X-ray diffraction enhanced imaging at synchrotron light source

Abstract

BackgroundChronic obstructive pulmonary disease (COPD) is one of the leading causes of morbidity and mortality worldwide, and emphysema is a common component of COPD. Currently, it is very difficult to detect early stage emphysema using conventional radiographic imaging without contrast agents, because the change in X-ray attenuation is not detectable with absorption-based radiography. Compared with the absorption-based CT, phase contrast imaging has more advantages in soft tissue imaging, because of its high spatial resolution and contrast.MethodsIn this article, we used diffraction enhanced imaging (DEI) method to get the images of early stage emphysematous and healthy samples, then extract X-ray absorption, refraction, and ultra-small-angle X-ray scattering (USAXS) information from DEI images using multiple image radiography (MIR). We combined the absorption image with the USAXS image by a scatter plot. The critical threshold in the scatter plot was calibrated using the linear discriminant function in the pattern recognition.ResultsUSAXS image was sensitive to the change of tissue micro-structure, it could show the lesions which were invisible in the absorption image. Combined with the absorption-based image, the USAXS information enabled better discrimination between healthy and emphysematous lung tissue in a mouse model. The false-color images demonstrated that our method was capable of classifying healthy and emphysematous tissues.ConclusionHere we present USAXS images of early stage emphysematous and healthy samples, where the dependence of the USAXS signal on micro-structures of biomedical samples leads to improved diagnosis of emphysema in lung radiographs.

On the equivalence of the X-ray scattering retrieval with beam tracking and analyser-based imaging using a synchrotron source

“…In XPCI the USAXS signal has been shown to be useful in various applications such as, for example, the better visualization [26,27] and the quantification [28] of microbubbles used as contrast agents. Moreover, a dependence of the scattering signal on lung disease state was observed [17,29,30]. Recently, it has been reported that the scattering signal of EI, in combination with the absorption signal, and the dependence on the radiation energy can help distinguishing threat materials from benign materials in a security control [31].…”

Detection of early pulmonary emphysema by multi‐contrast x‐ray Talbot‐Lau interferometer

“…Pulmonary function tests measure the air inhaled and exhaled by the lungs, which is not just relevant to emphysema disease. 5 A chest x-ray is often performed to assess the overall condition of the lungs and identify any abnormalities, which can help diagnose advanced pulmonary emphysema, but is not sensitive to mild and moderate emphysema. 6 Traditional computed tomography scan of the chest provides more details of the lungs than chest x-rays, allowing one to assess the severity, extent, and distribution of emphysema.…”

“…Current existing methods typically involve pulmonary function tests, chest x‐rays, and computed tomography (CT) scans. Pulmonary function tests measure the air inhaled and exhaled by the lungs, which is not just relevant to emphysema disease 5 . A chest x‐ray is often performed to assess the overall condition of the lungs and identify any abnormalities, which can help diagnose advanced pulmonary emphysema, but is not sensitive to mild and moderate emphysema 6 .…”