基于MRI与CT骨盆三维重建与测量的对比研究

Comparative Study of Reconstruction and Measurement of Three-dimensional Pelvic by CT and MRI

目的:对比基于MRI与CT三维骨盆重建的特点及测量研究。方法:对25例在南方医科大学南方医院志愿行盆腔CT及MRI检查的发育正常、无病理性骨盆女性,应用Mimics软件分别构建出骨盆三维模型,测量三维骨盆模型的各径线、角度值并进行分析。结果:1基于MRI与CT数据集的三维骨盆模型,解剖结构清晰、形态逼真、表面光滑。2CT、MRI三维骨盆测量的入口后矢状径、入口前后径、中骨盆横径、中骨盆后矢状径、出口后矢状径、骶骨长度,差异有统计学意义(t=3.132、-4.021、-4.048、-3.468、-2.956、5.203,P<0.01),但CT与MRI三维骨盆测量差值平均值的绝对值为4 mm;入口横径、骶耻内径、中骨盆前后径、出口横径、出口前后径、耻骨联合高度、骶骨弯度,差异无统计学意义(t=-1.126、0.947、0.796、-1.916、0.192、2.172、-2.484,P>0.05)。3MRI与CT三维骨盆测量具有较好的一致性,骨盆入口横径、入口后矢状径、入口前后径、骶耻内径、中骨盆横径、中骨盆后矢状径、中骨盆前后径、骨盆出口横径、骨盆出口后矢状径、出口前后径、耻骨联合高度、骶骨长度、骶骨弯度的95%一致性界限分别为(-5.1,4.1)mm、(-2.9,5.6)mm、(-5.4,2.3)mm、(-5.9,2.8)mm、(-6.6,4.5)mm、(-6.2,3.3)mm、(-6.1,2.5)mm、(-3.6,4.4)mm、(-4.2,4.9)mm、(-5.2,5.4)mm、(-3.1,4.8)mm、(-1.8,6.2)mm和(-6.5,3.9)mm。结论:1基于MRI与CT数据集均可构建出清晰逼真的三维骨盆。2MRI与CT三维骨盆测量值比较具有较好一致性,虽有6条径线值存在统计学差异,但平均值的绝对值小于5 mm,无临床意义。MRI三维骨盆测量可应用于临床。

Objective： To compare the reconstructived charateristic and measurement of three-dimensional pelvic based on CT and MRI. M ethods： CT scan and Thin slice MRl were performed in 25 femal volunteers in Southern Medical University. CT and MRl were imported into Mimics 10. 01 for 3D reconstruction. Using 3D models we measured follow indicators： transverse inlet diameter,posterior sagittal diameter of pelvic inlet,sagittal inlet,diagonalconjugate,biischial diameter,posterior sagittal diameter of midpelvis,sagittal midpelvic diameter,intertuberous distance,posterior sagittal diameter of outlet,sagittal outlet,penal height. sacrum length and sacrum curvature.Then,results were compared using a paired t test and Bland-Altman plot. Results： 1The 3D female pelvic models based on CT and MRI were reconstructed successfully which were clear and realistic with smooth surface. 2Significant differences were found in posterior sagittal diameter of pelvic inlet,sagittal inlet,biischial diameter,posterior sagittal diameter of midpelvis,posterior sagittal diameter of outlet,sacrum length between 3D female pelvic models based on CT and MRI.（ t = 3. 132、- 4. 021、- 4. 048、- 3. 468、- 2. 956、5. 203,P〈0. 01）. The absolute difference value of mean value was less than 5 mm between them. but there was no significant difference in transverse inlet diameter,diagonal conjugate,sagittal midpelvic diameter,intertuberous distance,sagittal outlet,penal height and sacrum curvature between 3D female pelvic models based on CT and MRI（ t =- 1. 126、0. 947、0. 796、- 1. 916、0. 192、2. 172、- 2. 484,P〈0. 05）. 3 Ihe Bland Ahman plots displayed relatively good agreement between 3D pelvic measurements based on CT and MRI,The 95% limits of agreement of transverse inlet diameter,posterior sagittal diameter of pelvic inlet,sagittal inlet,diagonal conjugate,biischial diameter,posterior sagittal diameter of midpelvis,sagittal midpelvic diameter,intertuberous distance,posterior sagittal diameter of outlet,sagittal outlet,penal were（- 5. 1,4. 1） mm、（- 2. 9,5. 6） mm、（- 5. 4,2. 3） mm、（- 5. 9,2. 8mm、（- 6. 6,4. 5）mm、（- 6. 2,3. 3） mm、（- 6. 1,2. 5） mm、（- 3. 6,4. 4） mm、（- 4. 2,4. 9） mm、（- 5. 2,5. 4） mm、（- 3. 1,4. 8）mm、（- 1. 8,6. 2） mm、（- 6. 5,3. 9） mm. Conclusions： 1The three-dimensional female pelvic models based on CT and MRI are reconstructed successfully; and the morphology of three-dimensional pelvic both by CT and MRI is clear and nature. 2The agreement between both three-dimensional pevic measurements is high. The absolute difference value of mean value is less than 5 mm,without clinical significance. Constructing 3D pelvic by MRI is suitable for clinical use.