Najafi Elmira, Bilston Lynne E, Song Xin, Bongers Andre, Stoodley Marcus A, Cheng Shaokoon, Hemley Sarah J
Faculty of Medicine and Health Sciences and.
Neuroscience Research Australia, and.
J Neurosurg Spine. 2016 Jun;24(6):941-8. doi: 10.3171/2015.10.SPINE15538. Epub 2016 Feb 26.
OBJECTIVE Syringomyelia pathophysiology is commonly studied using rodent models. However, in vivo studies of posttraumatic syringomyelia have been limited by the size of animals and lack of reliable noninvasive evaluation techniques. Imaging the rat spinal cord is particularly challenging because the spinal cord diameter is approximately 1-3 mm, and pathological lesions within the spinal cord parenchyma are even smaller. The standard technique has been histological evaluation, but this has its limitations. The aim of the present study was to determine whether syrinx size could be reliably measured using a preclinical high-field MRI animal system in a rat model of posttraumatic syringomyelia. METHODS The authors used an existing rat model of posttraumatic syringomyelia, which was created using a controlled pneumatic compression device to produce the initial spinal cord injury, followed by a subarachnoid injection of kaolin to produce arachnoiditis. T2-weighted MRI was performed on each animal using a 9.4-T scanner at 7, 10, and 13 weeks after injury. Animals were killed and syrinx sizes were calculated from in vivo MRI and histological studies. RESULTS MRI measurements of syrinx volume and length were closely correlated to histological measurements across all time points (Pearson product moment correlation coefficient r = ± 0.93 and 0.79, respectively). CONCLUSIONS This study demonstrates that high-field T2-weighted MRI can be used to measure syrinx size, and data correlate well with syrinx size measured using histological methods. Preclinical MRI may be a valuable noninvasive technique for tracking syrinx formation and enlargement in animal models of syringomyelia.
目的 脊髓空洞症的病理生理学通常使用啮齿动物模型进行研究。然而，创伤后脊髓空洞症的体内研究受到动物体型的限制，并且缺乏可靠的非侵入性评估技术。对大鼠脊髓进行成像尤其具有挑战性，因为脊髓直径约为1 - 3毫米，而脊髓实质内的病理病变甚至更小。标准技术一直是组织学评估，但这有其局限性。本研究的目的是确定在创伤后脊髓空洞症大鼠模型中，是否可以使用临床前高场MRI动物系统可靠地测量空洞大小。方法 作者使用现有的创伤后脊髓空洞症大鼠模型，该模型通过可控气动压缩装置造成初始脊髓损伤，随后蛛网膜下腔注射高岭土以产生蛛网膜炎。在损伤后7周、10周和13周，使用9.4 - T扫描仪对每只动物进行T2加权MRI检查。处死动物后，根据体内MRI和组织学研究计算空洞大小。结果 在所有时间点，空洞体积和长度的MRI测量值与组织学测量值密切相关（Pearson积矩相关系数r分别为± 0.93和0.79）。结论 本研究表明，高场T2加权MRI可用于测量空洞大小，且数据与使用组织学方法测量的空洞大小相关性良好。临床前MRI可能是一种用于追踪脊髓空洞症动物模型中空洞形成和扩大的有价值的非侵入性技术。
