基于MRI快速建立前交叉韧带三维数字化模型初步报道

目的　研究利用MRI二维图像快速建立前交叉韧带(ACL)三维数字化模型的方法，并评估模型的真实可靠程度。 方法　 选择 20 例临床诊断为ACL断裂患者的术前健侧MRI图像资料，导入自主开发的ACL快速分割技术软件（3D MIA ）进行图像分割，再以面绘制方式进行三维重建，建立膝关节及ACL三维数字化模型，测量模型的ACL长度、宽度、厚度及与人体三个解剖平面的角度，所得数据与前期解剖研究结果进行统计学的分析对比，评估模型的可靠程度。 结果 造模包括膝关节各骨性结构及前后交叉韧带，平均造模时间18 min，测量得到ACL长(39.80±1.86)mm、宽(5.80±1.83)mm、厚(9.96±1.26)mm；ACL与冠状面夹角(27.58±3.64)°、与矢状面夹角(39.82±4.01)°、与水平面夹角(22.27±4.23)°。与前期研究获得的相应数据对比，经独立样本t 检验，差异均无显著性意义(P>0.05)。 结论 利用自主开发的ACL分割技术及三维重建软件可以快速且较准确地建立健侧 ACL三维数字化模型，为计算机辅助ACL手术系统及实现ACL临床仿真个体化解剖重建提供了参考基础。

A preliminary report of fast establishment of three-dimensional digital models of anterior cruciate ligament based on MRI

Objective　To investigate the method of quickly establishing three-dimensional digital model of anterior cruciate ligament (ACL) using magnetic resonance imaging (MRI), and to evaluate authenticity and reliability of the model.　Methods　Contralateral knee joint MRI data of 20 cases of patients with clinical diagnosis of ACL rupture were selected. These data were imported into independent development of 3D-MIA software, and were segmented by the method of independent invention of ACL fast segmentation technology, and then three-dimensional substance digital models of ACL and the knee joint were established by carrying through three-dimensional reconstruction on the basis of surface rendering. The length, width, thickness, and the angle of ACL and the human body planes were measured on models. The results were compared with that of early anatomical results.　Results　Three-dimensional digital models included bones and cruciate ligaments of the knee joint . The average building time was 18 minutes. The mean length, width and thickness of ACL were (39.80±1.86), (5.80±1.83) and (9.96±1.26) mm respectively, and the angle formed by ACL and the coronal plane, sagittal plane, horizontal plane were (27.58±3.64)°, (39.82±4.01)° and (22.27±4.23)° respectively. Compared with the corresponding data of previous researches, by independent sample t-test, there was no significant difference (P>0.05).　Conclusions　A relatively reliable three-dimensional digital model of ACL and the knee joint can be quickly established using the novel ACL segmentation technology and 3D-MIA software, laying an foundation for establishing a complete set of computer aided ACL operation system and realizing the dream of simulational, individualized and anatomical reconstruction of ACL in the future.