Paper detail

Liquid Metal Angiography for Mega Contrast X-ray Visualization of Vascular Network

Visualizing the anatomical vessel networks plays a vital role in physiological or pathological investigations. However, identifying the fine structures of the smallest capillary vessels via conventional imaging ways remains a big challenge. Here, the room temperature liquid metal angiography was proposed for the first time to produce mega contrast X-ray images for multi-scale vasculature mapping. Gallium was used as the room temperature liquid metal contrast agent and perfused into the vessels of in vitro pig hearts and kidneys. We scanned the samples under X-ray and compared the angiograms with those obtained via conventional contrast agent--the iohexol. As quantitatively proved by the gray scale histograms, the contrast of the vessels to the surrounding tissues in the liquid metal angiograms is orders higher than that of the iohexol enhanced images. And the resolution of the angiograms has reached 100μm, which means the capillaries can be clearly distinguished in the liquid metal enhanced images. With tomography from the micro-CT, we also managed to reconstruct the 3-dementional structures of the kidney vessels. Tremendous clarity and efficiency of the method over existing approaches were experimentally demonstrated. It was disclosed that the usually invisible capillary networks now become distinctively clear in the gallium angiograms. This mechanism can be generalized and extended to a wide spectrum of 3-dimensional computational tomographic areas. It provides a soft tool for quickly reconstructing high resolution spatial channel networks for scientific researches or engineering applications where complicated and time consuming surgical procedures are no longer necessary.