锤骨-前庭桥接术中个体化人工镫骨精确塑形的三维影像和显微解剖基础

Measurement study of MDCT 3D reconstruction and microanatomy related to individual piston shaping on malleostapedotomy

目的:利用多排螺旋CT的多平面重建(MPR)及容积再现(VR)重建技术,结合显微解剖测量获取锤骨-前庭桥接术中个体化人工镫骨精确塑形必需的相关参数,并探讨CT无创测量的精度。方法:10例中国人无耳疾颞骨随机编号,经GELight Speed Ultra 64排螺旋CT扫描。扫描所得图像经AW4.1工作站进行MPR及VR操作,测量镫骨头至镫骨足板中央的距离(A线)、锤骨短突下缘至镫骨头的距离(B线)及锤骨短突下缘至镫骨足板中央处距离(C线),从而计算AB线间夹角。全部标本完成显微解剖直视操作,获相关参数,数据经SPSS10.0软件进行统计学处理。结果:CT测量及颞骨解剖测量获得A、B、C线长度分别为(3.42±0.86)mm和(3.60±0.94)mm,(3.42±0.80)mm和(2.96±0.42)mm,(5.86±0.60)mm和(6.22±1.10)mm;AB夹角分别为(141.05±30.07)°和(144.57±41.86)°,2组各项一一比较,均差异无统计学意义(P>0.05)。结论:多排螺旋CT的MPR及VR可直观形象地显示颞骨内部各结构之间的空间关系,完成A、B、C线及AB间夹角的精确测量,为锤骨-前庭桥接术中个体化人工镫骨塑形提供临床指导。

Objective： To study the management of basic parameters related to individual piston shaping on malleostapedotomy by MDST 3D reconstruction and microanatomy and to assess the accuracy of MDST method. Method：Ten Chinese temporal bones without ear diseases were numbered randomly and scanned by GE LightSpeed Ultra 64 rows of spiral CT. 3D structure of ossicular chain were reconstructed by MPR and VR methods in AW4. 1 workstation. Then measurements of distances between stapes head to stapes footplate （A line）,and manubrium to stapes head （B line）, and manubrium to stapes footplate（C line）, angle between line A and line B （angle AB） are completed. After that, all samples of temporal bone were undergone canal wall down mastoidectomy under microscope and the relevant measurements were completed. Result：The MPR and VR technique of MDCT reconstructed ossicular chain clearly, and revealed the spatial relationship between every structure stereoscopically. Respectively, lengths of A,B. C line by MDST and microanatomy are （3.42±0.86）mm and （3.60±0.94）mm, （3.42±0.80）mm and （2.96±0.42）mm, （5.86±0.60）mm and （6.22±1.10）mm, while angle AB （141.05±30.07）° and （144.57±41.86）°. There are no statistically significant differences between two groups （P〉0.05）. Conclusion：The MPR and VR technique of MDCT can clearly reconstructed the 3D shapes of the temporal bone and finish the exactly managements on A,B,C lines and AB angel which is crucial for shaping a individial piston on malleus-to-oval window surgery.