基于磁共振图像的膝关节软骨可视化初步研究

吴琼++++++高阳++++++牛广明++++++白雪菲++++++张元智+++++钱玉梅

[摘要] 目的 通过数字化分析，建立基于磁共振图像的膝关节软骨三维可视化。 方法 选取2014年5月～2015年5月内蒙古医科大学附属医院40名健康成人志愿者（男20名，女20名）。所有磁共振扫描均在GE Discovery MR 750 3.0T扫描机上进行，采用8通道膝关节线圈，患者仰卧位。序列采用Sag 3D FSPGR，将矢状位的原始图像数据以dicom格式导入Materialise Mimics Innovation Suite 16.0软件，采用半自动分割方式，选择软骨区域中像素平均强度的阈值为基准，选择股骨的近似中心作为半径搜索的原点，确定软骨边界，三维重建膝关节软骨并进行统计学分析。 结果 膝关节软骨平均厚度男性大于女性，膝关节软骨平均厚度在男性左、右侧平均分别为（2.87±0.33）、（2.86±0.31） mm；在女性左、右侧平均分别为（2.58±0.31）、（2.56±0.29）mm。同一性别的左、右两侧差异无统计学意义（P > 0.05），而同一侧在男、女性别之间差异有高度统计学意义（P < 0.01）。重建的软骨可以全方位观察其形态。 结论 Sag 3D FSPGR序列图像为更好地观察软骨形态提供相对精准的方法。

[关键词] 磁共振成像；软骨；三维重建

[中图分类号] R445.2 [文献标识码] A [文章编号] 1673-7210（2017）02（b）-0103-03

[Abstract] Objective To establish the 3D visualization of articular cartilage of knee joint based on magnetic resonance imaging by digitization analyse. Methods From May 2014 to May 2015， 40 healthy adult volunteers （male 20， female 20） from Affiliated Hospital of Inner Mongolia Medical University were selected. All MR scan were used GE Discovery MR 750 3.0T， with 8 channel knee-joint coil， patients took supine position. Sequence uesd Sag 3D FSPGR， T2 sagittal Images were transformed into Materialise Mimics Innovation Suite 16.0 software； Using semiautomatic segmentation way， threshold value of pixel average intensity in cartilage area was selected as standard， approximate center of femoral was selected as original point of radius searching， cartilage border was confirmed， three-dimensional models of the knee cartilage was reconstructed and statistical analysis was made. Results The average thickness of the articular cartilage in male was more than that in female， the male were （2.87±0.33） mm at the left side， and （2.86±0.31）mm at the right side； the female were （2.58±0.31） mm at the left side， and （2.56±0.29） mm at the right side； there was no significant difference in the left and right side of the same sex （P > 0.05）， but the difference was statistically significant between genders in the same side （P < 0.01）. Reconstructed cartilage could be omnibearing observed its form. Conclusion Sag 3D FSPGR sequence image may provide a relatively accurate method for the observation of cartilage morphology.

[Key words] MRI； Knee cartilage； Three-dimensional reconstruction

膝關节结构复杂，关节软骨以光滑、透明的海绵材料覆盖于胫骨平台和股骨髁之间。软骨形态改变是骨关节炎进展的重要生物标志。磁共振成像是广泛用于图像的膝关节，常规软骨MRI扫描序列已非常成熟，对关节软骨形态学改变具有很高的敏感性，但对于早期软骨损伤形态完整的显示不佳，随着MRI软硬件技术的提高，使得关节软骨病变的研究得到了快速发展，软骨分析、测量和可视化可以对软骨病变进行早期的发现和评估[1-5]，本研究通过混合MRI扫描序列对健康成……