Zheng Shaokuan, Xia Yang
Department of Physics and Center for Biomedical Research, Oakland University, Rochester, Michigan.
Cartilage. 2010 Jan 1;1(1):55-64. doi: 10.1177/1947603509359784.
The objective was to study the effect of phosphate salts and fixation solutions on the proton dynamics in articular cartilage in vitro. Microscopic magnetic resonance imaging (μMRI) T(2) anisotropy and nuclear magnetic resonance (NMR) double quantum-filtered (DQF) spectroscopy were used to study the full-thickness articular cartilage from several canine humeral heads. The in-plane pixel size across the depth of the cartilage tissue was 13 μm. The acid phosphate salt was an effective exchange catalyst for proton exchange in the cartilage with an organized structure of collagen fibrils, while the alkaline phosphate salt was not. For cartilage tissue containing less organized collagen fibrils, both acid and alkaline phosphate salts have no significant effect on the T(2) value at low concentration but decrease the T(2) value at high concentration. The solutions of NaCl, KCl, CaCl(2), and D-PBS were found to have no significant effect on T(2) and DQF in cartilage. This study demonstrates the ability to modify the proton exchange in articular cartilage using the solutions of phosphate salts. The ability to modify the proton exchange in articular cartilage can be used to modulate the laminar appearance of articular cartilage in MRI.
目的是研究磷酸盐和固定液对体外关节软骨中质子动力学的影响。使用显微磁共振成像（μMRI）T(2)各向异性和核磁共振（NMR）双量子滤波（DQF）光谱来研究取自多个犬肱骨头的全层关节软骨。软骨组织深度方向的平面像素大小为13μm。酸性磷酸盐是具有胶原纤维组织结构的软骨中质子交换的有效交换催化剂，而碱性磷酸盐则不是。对于胶原纤维组织较少的软骨组织，低浓度时酸性和碱性磷酸盐对T(2)值均无显著影响，但高浓度时会降低T(2)值。发现NaCl、KCl、CaCl(2)和D-PBS溶液对软骨中的T(2)和DQF无显著影响。本研究证明了使用磷酸盐溶液改变关节软骨中质子交换的能力。改变关节软骨中质子交换的能力可用于调节MRI中关节软骨的分层外观。
