School of Chemistry, Tel Aviv University, Tel Aviv, Israel.
NMR Biomed. 2010 Jul;23(6):554-62. doi: 10.1002/nbm.1493.
In order to investigate intervertebral disc (IVD) degeneration and repair, a quantitative non-invasive tool is needed. Various MRI methods including qCPMG, which yields dipolar echo relaxation time (T(DE)), magnetization transfer contrast (MTC), and (1)H and (2)H double quantum filtered (DQF) MRI were used in the present work to monitor changes in rat IVD after ablation of the nucleus pulposus (NP), serving as a model of severe IVD degeneration. In the intact IVD, a clear distinction between the annulus fibrosus (AF) and the NP is obtained on T(2) and T(DE) weighted images as well as on MTC maps, reflecting the high concentration of ordered collagen fibers in the AF. After ablation of the NP, the distinction between the compartments is lost. T(2) and T(DE) relaxation times are short throughout the disc and MTC is high. (1)H and (2)H DQF signal, which in intact discs is obtained only for the AF, is now observable throughout the tissue. These results indicate that after ablation, there is an ingression of collagen fibers from the AF into the area that was previously occupied by the NP, as was confirmed by histology.
为了研究椎间盘（IVD）退变和修复，需要一种定量的非侵入性工具。本研究采用各种 MRI 方法，包括 qCPMG，其产生偶极子回波弛豫时间（T(DE)）、磁化传递对比（MTC）和（1）H 和（2）H 双量子过滤（DQF）MRI，以监测髓核切除（NP）后大鼠 IVD 的变化，作为严重 IVD 退变的模型。在完整的 IVD 中，在 T(2)和 T(DE)加权图像以及 MTC 图上可以清楚地区分纤维环（AF）和 NP，反映了 AF 中有序胶原纤维的高浓度。NP 切除后，隔室之间的区别消失。整个椎间盘的 T(2)和 T(DE)弛豫时间都很短，MTC 很高。在完整的椎间盘中仅能获得 AF 的（1）H 和（2）H DQF 信号现在可以在整个组织中观察到。这些结果表明，切除后，胶原纤维从 AF 侵入到以前由 NP 占据的区域，这一点通过组织学得到了证实。
