3.0 T MRI上正常成人膝关节软骨体积的定量测量及其临床意义

目的：提供正常成人膝关节关节软骨总体积的参考值,研究膝关节各部分软骨体积所占总体积的比重,探讨软骨体积与年龄、性别、身高、体重的关系.方法：选取无关节外伤及手术史、无膝关节痛的健康志愿者140例,分为7个年龄组,在3.0 T MR上使用水激发3D-MEDIC扫描序列对膝关节进行矢状位重复扫描.所获图像使用半自动软件OsiriX进行膝关节软骨的体积测量及三维重建.结果：膝关节软骨总体积的平均值为（18.16±4.36）cm^3,其中,股骨软骨体积最大,髌骨及胫骨外侧髁次之,胫骨内侧髁最小,所占平均比重分别为（58.1±3.3）%、（18.7±2.0）%、（13.3±1.8）%及（10.0±1.9）%,其中以胫骨内侧髁比重变化程度最大（CV=19%）.男性软骨平均体积大于女性,分别为（21.62±3.63）cm^3和（14.70±2.83）cm^3.膝关节软骨总体积大小以及各部分软骨体积与年龄的增长没有明显相关性（P＞0.05）.膝关节软骨总体积与身高及体重呈正相关（P＜0.001）.结论：关节软骨体积与年龄没有明显关系,与身高及体重呈正相关,因此在评估膝关节软骨病损的体积改变时需结合性别、身高及体重等因素综合评价.

Quantitative Measurement of the Normal Knee Joint Cartilage Volume at 3.0 T MRI

Objective：To provide the normal reference value of cartilage volumes in the knee joints of healthy adults, study the percentage of cartilages in the patellar, femoral, and tibial and analyze the correlation of the volumes with age, sex, height and weight. Methods：We examed the knee joints of 140 healthy volunteers who had no past history of joint disease or trauma or operation . The studied population was divided into 7 groups by age. Each knee was examed twice using a sagittal 3D -MEDIC（ Multi Echo Data Imaging Combination） sequence with water excitation. The cartilage volumes and the three - dimensional reconstruction were determined by a semiautomatic software OsiriX. Results：The mean total volume of the knee joint cartilage was （18.16 ±4.36）cm^3 ,the femoral cartilage volume occupied the highest percentage of the total knee joint volume, followed by the patellar and lateral tibial cartilage, the lowest one was the medial tibial cartilage. The mean percentage of each compartments was （ 58.1 ±3.3 ） % , （ 18.7 ±2.0） % , （ 13.3 ± 1.8 ） % and （ 10.0 ± 1.9） % respectively. The medial tibial cartilage volume showed the highest Coefficient Variations （CV%） of the percentage（ CV% = 19% ）. Males displayed higher cartilage volumes than females. The mean cartilage vol- ume in males was （ 21.62 ±3.63 ） cm^3 , in female was （ 14.70 ± 2.83 ） cm^3. There was no significant correlation of the total cartilage volume and each compartment of the joint cartilage with age（ P 〉0.05 ） . The total cartilage volume was positively correlated with body height （ r = 0.48, P 〈 0. 001 ） and weight （ r = 0.30, P 〈 0. 001 ）. Conclusions：The mean total volume of the knee joint cartilage is （18.16± 4.36） cm^3, each compartment occupies a relatively variable percentage of the total knee joint volume. The cartilage volume in males is higher than in females. There is no significant correlation of the knee joint cartilage volume with age. The cartilage volume is positively correlated with body height and weight. Therefore, the estimation of cartilage volume changes with cartilage lesion should consider tile factors of sex, body height and weight.