Visualization of mouse spinal cord intramedullary arteries using phase- and attenuation-contrast tomographic imaging

Abstract

Many spinal cord circulatory disorders present the substantial involvement of small vessel lesions. The central sulcus arteries supply nutrition to a large part of the spinal cord, and, if not detected early, lesions in the spinal cord will cause irreversible damage to the function of this organ. Thus, early detection of these small vessel lesions could potentially facilitate the effective diagnosis and treatment of these diseases. However, the detection of such small vessels is beyond the capability of current imaging techniques. In this study, an imaging method is proposed and the potential of phase-contrast imaging (PCI)- and attenuation-contrast imaging (ACI)-based synchrotron radiation for high-resolution tomography of intramedullary arteries in mouse spinal cord is validated. The three-dimensional vessel morphology, particularly that of the central sulcus arteries (CSA), detected with these two imaging models was quantitatively analyzed and compared. It was determined that both PCI- and ACI-based synchrotron radiation can be used to visualize the physiological arrangement of the entire intramedullary artery network in the mouse spinal cord in both two dimensions and three dimensions at a high-resolution scale. Additionally, the two-dimensional and three-dimensional vessel morphometric parameter measurements obtained with PCI are similar to the ACI data. Furthermore, PCI allows efficient and direct discrimination of the same branch level of the CSA without contrast agent injection and is expected to provide reliable biological information regarding the intramedullary artery. Compared with ACI, PCI might be a novel imaging method that offers a powerful imaging platform for evaluating pathological changes in small vessels and may also allow better clarification of their role in neurovascular disorders.

High-resolution 3D visualization of ductular proliferation of bile duct ligation-induced liver fibrosis in rats using x-ray phase contrast computed tomography

“…Imaging techniques, such as CT, MRI, and magnetic resonance angiography (MRA), have inherent advantages in the direct visualization of anatomical structure of hepatic vessels. Unfortunately, the vascular changes at the micron or submicron levels are invisible to current imaging techniques due to insufficient contrast and spatial resolution 21, 22 . Micro-CT, depending on the absorption-contrast imaging, has been used as a visualization tool for the microstructures of the samples at high resolutions, but soft tissues imaging are typically impossible via micro-CT without the use of contrast agents because of small differences in attenuation values 22 .…”

“…Unfortunately, the vascular changes at the micron or submicron levels are invisible to current imaging techniques due to insufficient contrast and spatial resolution 21, 22 . Micro-CT, depending on the absorption-contrast imaging, has been used as a visualization tool for the microstructures of the samples at high resolutions, but soft tissues imaging are typically impossible via micro-CT without the use of contrast agents because of small differences in attenuation values 22 . A previous study showed that PCCT could obtain high depiction of microstructural details and soft tissue contrast as well as higher contrast-to-noise ratios than absorption-based micro-CT 23 .…”

Three-dimensional visualization of microvasculature from few-projection data using a novel CT reconstruction algorithm for propagation-based X-ray phase-contrast imaging

“…In general, by extending PBI to CT (PBCT), PBCT can be used for high-resolution 3D visualization of the internal detailed structures in weakly absorbing objects. Compared with SR-µCTA, SR-based PBCT (SR-PBCT) might be a promising novel approach to enable 3D visualization and precise quantification of microvascular networks without the need for contrast agent injection [10]. To date, SR-PBCT has been widely used in biomedical and preclinical experimental studies to reconstruct the microvasculature of tissues and organs, including nerve tissue [11], alveoli [12], kidney [13], liver [14], spinal cord [15], and brain [16].…”