漏斗胸畸形程度对心脏形态和位置等影响的螺旋CT评价

Effect of the degree of sternal depression on the cardiac rotation in pectus excavatum:evaluation with spiral CT

目的 评价漏斗胸畸形的螺旋CT表现及胸骨凹陷对心脏形态和位置等的影响。方法 搜集 1999～ 2 0 0 3年行螺旋CT检查并经手术治疗的漏斗胸 32例。在CT图像上 ,观察和测定漏斗胸的胸骨凹陷深度、CT凹陷指数 [左胸矢状内径 (b)与胸椎体前缘至胸骨后缘距离 (a)的比值 ]、心脏旋转角度 (胸椎体前缘至心尖连线与胸矢状线的夹角 )和左下肺静脉干轴线与胸矢状线的夹角 (PV角 ) ,评价它们之间的关系。结果 32例漏斗胸显示了不同程度的胸骨凹陷 ,平均凹陷深度为 (2 1± 7)mm ,CT凹陷指数 (b/a )为 2 9± 1 8,心脏旋转角为 (5 5 9± 9 8)° ,静脉角为 (49 8± 14 0 )°。胸骨轻度畸形 11例 (b/a <2 4 )、中度 12例 (b/a =2 4～ 2 9)、重度 9例 (b/a >2 9) ,胸骨平均凹陷深度分别为17、2 1、2 7mm ,三者间差异有非常显著性意义 (F =5 39,P <0 0 1) ;心脏旋转角分别为 4 9 7°、5 5 5°和6 6 9° ,三者间差异有非常显著性意义 (F =7 4 4 ,P <0 0 1) ;而PV角分别为 5 8 7°、4 6 5°和 4 2 4° ,三者间差异也有显著性意义 (F =3 33,P <0 0 5 )。随着CT凹陷指数的增加 ,心脏旋转角度也增大 ,两者的相关系数为 0 73(P <0 0 1)。

Objective To evaluate the effects of the degree of sternal depression on the cardiac rotation in pectus excavatum by using spiral CT.Methods Spiral CT features of 32 patients with surgically corrected pectus excavatum were retrospectively reviewed.They included 27 males and 5 females ranging in age from 6 months to 17 years (mean,6.3 years).Analysis was based on relationship among the degree of sternal depression,CT depression index,cardiac rotation angle,and PV angle.Results 32 cases of pectus excavatum presented the sternal depression (21±7)mm,CT depression index 2.9±1.8,cardiac rotation angle (55.9± 9.8)°,and PV angle (49.8±14.0)°,respectively.The sternal depression (17 mm) in cases with CT depression index less than 2.4 was smaller than those with CT depression index 2.4～2.9 (21 mm) and CT depression index larger than 2.9 (27 mm) (F=5.39,P<0.01).Cardiac rotation angle (49.7 °) in cases with CT depression index less than 2.4 was smaller than those with CT depression index 2.4～2.9 (55.5 °) and CT depression index larger than 2.9 (66.9 °) (F=7.44,P<0.01).PV angle (58.7 °) in cases with CT depression index less than 2.4 was larger than those with CT depression index 2.4～2.9 (46.5 °) and CT depression index more than 2.9 (42.4°) (F=3.33,P<0.05).Cardiac rotation angle of pectus excavatum had positive correlation with the CT depression index (γ=0.73,P<0.01).Conclusion Spiral CT is a better tool for revealing chest deformity and corresponding cardiac rotation.The degree of sternal depression in pectus excavatum directly influences the cardiac rotation,and they had positive correlation.