Three-dimensional visualization of rat brain microvasculature following permanent focal ischaemia by synchrotron radiation

Abstract

Objective: Identifying morphological changes that occur in microvessels under both normal and ischaemic conditions is crucial for understanding and treating stroke. However, conventional imaging techniques are not able to detect microvessels on a micron or sub-micron scale without angiography. In the present study, synchrotron radiation (SR)-based X-ray in-line phase contrast imaging (ILPCI) was used to acquire high-resolution and high-contrast images of rat brain tissues in both normal and ischaemic states. Methods: ILPCI was performed at the Shanghai Synchrotron Radiation Facility, Shanghai, China, without the use of contrast agents. CT slices were reformatted and then converted into three-dimensional (3D) reconstruction images to analyse subtle details of the cerebral microvascular network.Results: By using ILPCI, brain vessels up to 11.8 mm in diameter were resolved. The number of cortical and penetrating arteries detected were found to undergo a remarkable decrease within the infarct area. 3 days after permanent ischaemia, vascular masses were also observed in the peripheral region of the infarcts. Conclusion: SR-based ILPCI-CT can serve as a powerful tool to accurately visualize brain microvasculature. The morphological parameters of blood vessels in both CT slices and 3D reconstructions were determined, and this approach has great potential for providing an effective diagnosis and evaluation for rehabilitation therapy for stroke. Advances in knowledge:In the absence of contrast agent, the 3D morphologies of the brain microvasculature in normal and stroke rats were obtained using SRbased ILPCI. SR imaging is a sensitive and promising method which can be used to explore primary brain function.

The Angiogenic Effect of microRNA-21 Targeting TIMP3 through the Regulation of MMP2 and MMP9

“…Meanwhile, the synchrotron radiation micro-computed tomography (SRμCT) imaging technique was introduced to achieve high-resolution, non-invasive 3D imaging of the complicated neurovascular networks in the rat spinal cord after injury. The synchrotron radiation light source, which is characterized by high flux density, high coherence, and monochromaticity, could obtain high-resolution imaging of the microvasculature to the submicro-level in the brain, hepatic sinusoids and rabbit eye[ 27 – 29 ]. Using this technique, the effect of miR-21 on the repair process of the microvascular network can be visualized in three dimensions (3D) after SCI in rats.…”

SRμCT Reveals 3D Microstructural Alterations of the Vascular and Neuronal Network in a Rat Model of Chronic Compressive Thoracic Spinal Cord Injury

“…In addition, no evidence exists regarding 3D alterations of neurovascular morphology in response to thoracic spinal cord compression. Synchrotron radiation microtomography (SRμCT) has been recognized as a powerful tool to explore the 3D structure of biospecimens across a large spatial range, down to submicron resolutions [20][21][22][23][24][25][26]. In a previous study, we reported the feasibility of using SRμCT to visualize and quantitatively analyze the 3D morphology of spinal cord microvasculature after acute injuries [21,24,27].…”

Three-dimensional imaging of microvasculature in the rat spinal cord following injury

“…The high intensity, high coherence, and monochromatic characteristics of SR beam light have enabled the SR-based imaging technique to obtain high-resolution images of vessel networks at micro- and even submicro-levels. In experimental studies, this method has been applied to the visualization of the 3D morphology of the microvasculature in the heart, hind limbs, tumors, and the brain 13 14 15 16 17 . However, the method’s utility for 3D visualization of the pathologic changes of angioarchitecture in trauma-induced spinal cords has not been investigated.…”