Schambach Sebastian J, Bag Simona, Steil Volker, Isaza Cristina, Schilling Lothar, Groden Christoph, Brockmann Marc A
Department of Neuroradiology, University of Heidelberg, Medical Faculty Mannheim, Mannheim, Germany.
Stroke. 2009 Apr;40(4):1444-50. doi: 10.1161/STROKEAHA.108.521740. Epub 2009 Feb 12.
Animal models developed in rats and mice have become indispensable in preclinical cerebrovascular research. Points of interest include the investigation of the vascular bed and the morphology and function of the arterial, capillary, and venous vessels. Because of their extremely small caliber, in vivo examination of these vessels is extremely difficult. In the present study we have developed a method to provide fast 3D in vivo analysis of cerebral murine vessels using volume computed tomography-angiography (vCTA).
Using an industrial X-ray inspection system equipped with a multifocus cone beam X-ray source and a 12-bit direct digital flatbed detector, high-speed vCTA (180 degrees rotation in 40 s. at 30 fps) was performed in anesthetized mice. During the scan an iodinated contrast agent was infused via a tail vein. Images were reconstructed using a filtered backprojection algorithm. Image analysis was performed by maximum intensity projection (MIP) and 3D volume reconstruction.
All mice tolerated i.v. injection of the iodinated contrast agent well. Smallest achievable voxel size of raw data while scanning the whole neurocranium was 16 mum. Anatomy of cerebral vessels was assessable in all animals, and anatomic differences between mouse strains could easily be detected. Mean vessel diameter was measured in C57BL/6 and BALBc mice. Changes of vessel caliber were assessable by repeated vCTA.
Ultra fast in vivo vCTA of murine cerebral vasculature is feasible at resolutions down to 16 mum. The technique allows the assessment of vessel caliber changes in living mice, thus providing an interesting tool to monitor different features such as vasospasm or vessel patency.
大鼠和小鼠模型已成为临床前脑血管研究中不可或缺的工具。研究重点包括血管床以及动脉、毛细血管和静脉血管的形态与功能。由于这些血管口径极小，对其进行体内检查极具难度。在本研究中，我们开发了一种利用容积计算机断层血管造影（vCTA）对小鼠脑血管进行快速三维体内分析的方法。
使用配备多焦点锥束X射线源和12位直接数字平板探测器的工业X射线检测系统，对麻醉后的小鼠进行高速vCTA（40秒内旋转180度，每秒30帧）。扫描过程中经尾静脉注入碘化造影剂。图像采用滤波反投影算法重建。通过最大强度投影（MIP）和三维容积重建进行图像分析。
所有小鼠对静脉注射碘化造影剂耐受性良好。扫描整个颅骨时，原始数据可达到的最小体素大小为16微米。所有动物的脑血管解剖结构均可评估，且能轻易检测到不同小鼠品系之间的解剖差异。测量了C57BL/6和BALBc小鼠的平均血管直径。通过重复vCTA可评估血管口径的变化。
对小鼠脑血管进行超快速体内vCTA，在低至16微米的分辨率下是可行的。该技术能够评估活体小鼠血管口径的变化，从而为监测血管痉挛或血管通畅等不同特征提供了一种有趣的工具。
