Transport of Iodine Is Different in Cartilage and Meniscus
Transport of Iodine Is Different in Cartilage and Meniscus
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DOI：
10.1007/s10439-015-1513-2
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发表时间：
2016-07-01
影响因子：
3.8
通讯作者：
Toyras, J.
中科院分区：
文献类型：
--
作者：
Honkanen, J. T. J.;Turunen, M. J.;Toyras, J.
对比增强计算机断层扫描（CECT）已提出诊断软骨和半月板损伤和退变。由于两种组织可以同时成像，因此CECT可以提供一种综合评估膝关节健康状况的方法。由于软骨和半月板的组成和结构不同，我们假设阴离子造影剂的运输特性在组织之间也不同。这将影响CECT图像的解读，值得调查。为了澄清这一点，我们旨在确定阴离子碘（q = -1, M = 126.9 g/mol）的传输运动学，假设不受空间位阻的显着影响，因此提供比大分子造影剂（例如，ioxaglate）更快的传输。从健康牛（n = 10）髌骨和半月板制备圆柱形样品（d = 6 mm, h = 2 mm），浸泡在等渗磷酸盐缓冲的NaI溶液（20 mgI/mL）中，随后在20个时间点用micro-CT成像，直至23 h。随后，测定组织中的标准化衰减和造影剂通量，以及水，胶原蛋白和蛋白多糖（PG）含量。半月板在平衡状态下的归一化衰减更高（p = 0.005）。造影剂通量在10 min时半月板较低（p = 0.005），而在30 ~ 120 min时较高（p < 0.05）。在两种组织中，造影剂在平衡状态下的分布与深度方向的PG分布相反。综上所述，碘在软骨和半月板中的转运是不同的，特别是在浸泡后的前2小时。这是一个重要的发现，应考虑在同时进行CECT软骨和半月板。
Contrast enhanced computed tomography (CECT) has been proposed for diagnostics of cartilage and meniscus injuries and degeneration. As both tissues may be imaged simultaneously, CECT could provide a method for comprehensive evaluation of knee joint health. Since the composition and structure of cartilage and meniscus are different, we hypothesize that transport characteristics of anionic contrast agents also differ between the tissues. This would affect interpretation of CECT images and warrants investigation. To clarify this, we aimed to determine the transport kinematics of anionic iodine (q = -1, M = 126.9 g/mol), assumed to not be significantly affected by the steric hindrance, thus providing faster transport than large molecule contrast agents (e.g., ioxaglate). Cylindrical samples (d = 6 mm, h = 2 mm) were prepared from healthy bovine (n = 10) patella and meniscus, immersed in isotonic phosphate-buffered NaI solution (20 mgI/mL), and subsequently imaged with a micro-CT at 20 time points up to 23 h. Subsequently, normalized attenuation and contrast agent flux, as well as water, collagen, and proteoglycan (PG) contents in the tissues were determined. Normalized attenuation at equilibrium was higher (p = 0.005) in meniscus. Contrast agent flux was lower (p = 0.005) in the meniscus at 10 min, but higher (p < 0.05) between 30 and 120 min. In both tissues, contrast agent distribution at equilibrium suggested an inverse agreement with the depth-wise PG distribution. In conclusion, iodine transport into cartilage and meniscus was different, especially between the first 2 hours after the immersion. This is an important finding which should be considered during simultaneous CECT of cartilage and meniscus.