【作者】 马聪；

【导师】 尉传社；

【作者基本信息】 江苏大学 ， 影像医学与核医学， 2010， 硕士

【摘要】 第一部分：3.0T MRI上半自动软件软骨体积定量测量的可重复性及准确性研究目的：评估在3.0T MRI上使用半自动软件OsiriX测量膝关节软骨体积的可重复性及准确性。方法：在3.0T MR上使用磁共振(MR)轴位水激发三维快速小角度激发(3D-FLASH[we])序列对30名健康志愿者和30名骨性关节炎(OA)患者的右膝关节进行重复扫描。全部图像由3名观察者分别使用开放源软件OsiriX髌骨进行软骨的半自动分割及随机工作站进行人工分割,计算软骨体积,比较两种方法测量软骨体积所需时间、可重复性及测量结果。结果：①OsiriX软件分割比人工分割节省50%以上时间；②正常组OsiriX软件分割及人工分割的观察者间可重复性误差分别为4.9%和9.8%,高年资观察者内部可重复性误差分别为0.8%和1.3%,个体内部可重复性误差范围分别为0.1%-1.1%和0.5%～1.6%,前者各项可重复性误差均低于后者(P<0.05)；OA组OsiriX软件分割及人工分割的观察者间可重复性误差分别为6.2%和11.3%,高年资观察者内部可重复性误差分别为1.5%和2.7%,个体内部可重复性误差范围分别为0.7%-2.0%和1.2%-3.7%,前者各项可重复性误差均低于后者(p<0.05)；③正常组OsiriX软件与人工分割软骨体积测量结果之间的系统配对误差为-3.8%,随机配对误差为(4.7±2.7)%,测量结果差异无统计学意义(t=0.92,P=0.36)；OA组OsiriX软件及人工分割软骨体积测量结果之间的系统配对误差为-5.4%,随机配对误差为(6.3±4.0)%,测量结果差异无统计学意义(t=0.74,P=0.47)。结论：与人工分割相比,OsiriX半自动分割测量软骨体积具有省时、观察者间及观察者内可重复性高、有相对固定标准等明显优势,可用于临床及多中心大样本量研究。第二部分：3.0T MRI上正常成人膝关节软骨体积的定量测量目的：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、身高及体重的关系。方法：选取无关节外伤及手术病史,无膝关节痛的健康志愿者140例,分为7个年龄组,在3.0T MR上使用水激发三维多回波数据联合成像(3D-MEDIC[we])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,在整个膝关节软骨中,股骨软骨所占体积最大,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)%,其中以胫骨内侧髁软骨比重变化程度最大(CV=19%)。男性软骨平均体积大于女性,平均总体积分别为(21.62±3.63)cm~3和(14.70±2.83)cm~3。正常人膝关节软骨总体积大小与年龄的增长没有显著相关性(r=-0.19),各部分软骨体积与年龄亦没有明显相关性。膝关节软骨总体积与身高及体重成正相关(r=0.48,P<0.001；r=0.30,P<0.001)。结论：正常成人膝关节软骨总体积大小约(18.16±4.36)cm~3,膝关节不同部分软骨占软骨总体积的比重及变化程度均不等。男性软骨体积大于女性。关节软骨体积与年龄没有明显相关性,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。第三部分：3.0T MRI上骨性关节炎患者膝关节软骨体积的定量测量目的：在3.0T MRI使用水激发3D-MEDIC序列对正常人和OA患者膝关节软骨体积进行测量及对比分析,从而探讨3.0T MRI上软骨体积测量在OA中的应用价值。方法：选择具有膝关节疼痛和功能障碍等症状,无膝关节外伤及膝关节手术病史的男性OA患者作为研究对象,58例纳入实验,结合WOMAC骨性关节炎指数评分及K-L放射学诊断标准将OA患者分为轻、中、重度三组；选择无关节炎及外伤病史,无膝关节痛的健康男性20名作为对照组。58名OA患者及20名健康男性均使用3D-MEDIC[we]序列进行矢状位MRI扫描。所获图像使用半自动软件OsiriX进行膝关节软骨体积的测量,对所测数据进行身高及体重校正,分析比较正常组与病变各组之间的差异性。结果：通过对膝关节OA病变各组软骨体积的测量并与正常组对比,轻度OA组各部分关节软骨体积与正常组之间不存在统计学差异,而中、重度OA组之间及中、重度OA组与正常组之间软骨各部分软骨体积比较存在统计学差异(P<0.05)。结论：通过关节软骨OA组与对照组体积测量对比分析：发现OA患者膝关节各部分软骨体积随着OA病情的加重,其体积逐渐变小,以重度OA患者较明显,3.0T MRI上软骨体积测量可为OA软骨病损提供定量依据。更多还原

【Abstract】 Part 1:Reproducibility and Accuracy of Quantitative Knee Cartilage Volume measurements using semi-automated software by MRI at 3.0TObjective:To evaluate the reproducibility and accuracy of semi-automated software OsiriX in the assessment of knee cartilage volume at 3.0T MR.Methods:The right knees of thirty healthy subjects and thirty patients with osteoarthritis were scanned twice with 3.0T MR using 3D-FLASH sequence with selective water excitation. Cartilage volume of the patellar compartment was determined with a validated open-source software OsiriX and manual segmentation separately by 3 observers using the MRI data sets. After calculating the cartilage volumes, the segmentation processing times, the reproducibility and volume results were compared between two segmentations.Results:①Compared with the manual segmentation, a time saving of at least 50% for cartilage volume measurement was achieved with OsiriX software segmentation.②In the normal group,the interobserver reproducibility error was 4.9% and 9.8% with OsiriX software segmentation and manual segmentation, respectively; the intraobserver reproducibility error of high experienced observer were 0.8% and 1.3%, the interindividual reproducibility error range were 0.1%～1.1% and 0.5%～1.6%. The reproducibility error of OsiriX software segmentaion proved to be significantly smaller than manual segmentation (P<0.05).③In the OA group,the interobserver reproducibility error was 6.2% and 11.3% with OsiriX software segmentation and manual segmentation, respectively; the intraobserver reproducibility error of high experienced observer were 1.5% and 2.7%, the interindividual reproducibility error range were 0.7%～2.0% and 1.2%～3.7%. The reproducibility error of OsiriX software segmentaion proved to be significantly smaller than manual segmentation (P< 0.05).④In the normal group,systematic pairwise difference between results obtained with OsiriX software measurement and manual measurement was-3.8% and absolute pairwise difference was (4.7±2.7)%. There was no statistical difference between the volume results measured by two techniques (t=0.92, P=0.36).⑤In the OA group, systematic pairwise difference between results obtained with OsiriX software measurement and manual measurement was-5.4% and absolute pairwise difference was(6.3±4.0)%. There was no statistical difference between the volume results measured by two techniques (t=0.74, P=0.47).Conclusion:Compared to manual segmentation, cartilage volume measurement with OsiriX semi-automated segmentation is faster and has higher inter- and intraobserver reproducibility with relatively fixed standard. This technique may therefore be used for clinical and multi-center trials of large sample.Part 2:Quantitative Measurement of the Knee joint Cartilage Volume in normal adult at 3.0T MRIObjective:To provide the normal reference value of cartilage volumes in the knee joints of healthy adults,study the percentage of the patellar, femoral, and tibial cartilages and analyze the correlation of the volumes with age,sex,body 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 by age into 7 groups. Each knee was examed twice using a sagittal 3D-MEDIC sequence with water excitation. The cartilage volumes and the three-dimensional reconstruction was determined by a semiautomatic software OsiriX.Results:The mean total volume of the knee joint cartilage was (18.16±4.36)cm3, the femoral cartilage volume occupied the highest percentage of the total knee joint volume, then 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 total volume of cartilage in males was (21.62±3.63)cm3, in female was(14.70±2.83) cm3. There was no significant correlation of the total cartilage volume with age(r=-0.19), the same to each compartment of the joint cartilage. The total cartilage volume was positively correlated with body height (r=0.48,P<0.001) and weight(r=0.30,P<0.001).Conclusion:The mean total volume of the knee joint cartilage in normal adult is (18.16±4.36)cm3, 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 the factors of sex, body height and weight.Part 3:Quantitative Measurement of Knee Cartilage volume in Osteoarthritis at 3.0 T MRIObjective:The knee cartilage volumes of various degrees of OA patients was determined by using a sagittal 3D-MEDIC sequence with water excitation at 3.0T MRI, and the clinical value of knee cartilage volume measurement at 3.0 MRI in OA are also evaluated after being compared with those in the normal group. Methods:58 male subjects having the symptoms of knee pain and function impairment in their knees were included, and all the cases had no history of trauma and operation.According to the OA index made by WOMAC and K-L radiological diagnosis standard, the cases with OA in the knee could be further classified into gentle, medium and serious groups.20 normal male subjects were selected for contrast. All of the knees were scanned by a sagittal 3D-MEDIC sequence with water excitation. The knee cartilage volumes was determined by a semiautomatic software OsiriX and the measurements were adjusted for height and weight.The volume measurements of OA groups were compared with normal group.Results:Comparing articular cartilage volume between in the OA cases of various degrees and in the healthy volunteers, in the gentle OA group, there was no statistical difference of knee cartilage volume with that in the normal volunteers, while that in medium and serious OA groups was significant different from that in the normal group.Conclusion:By comparing of articular cartilage volume between in the OA cases and in the healthy volunteers, we observed that the articular cartilage volume of each compartment of the knee joint attenuated gradually, following with the aggregated OA disease, especially in the serious group. The cartilage volume measurement at 3.0T MRI could offer quantitative evidence for OA cartilage defects.更多还原