VRT、MIP及MPR对传导性耳聋的诊断分析

The significance of VRT,MIP and MPR in diagnosis of conductive deafness

目的探讨多层螺旋CT容积再现技术(VRT)、最大密度投影(MIP)及多平面重建(MPR)在听骨链畸形、外伤及炎症等病变所致的传导性耳聋的诊断作用。方法自2011年1月至2019年1月对临床诊断传导性耳聋的患者均行颞骨容积扫描,层厚0.625 mm,重叠0.3 mm,并用骨算法重建,再分别行单侧颞骨靶重建,将所得结果传至工作站行听骨链容积再现重建及最大密度投影重建观察,从中选择70例存在病变的听骨链进行分析。结果70例听骨链病变中,先天发育畸形所致40例,占57.1%;中耳胆脂瘤破坏所致21例,占30%;外伤所致9例,占12.9%。VRT、MIP和MPR三种后处理方法对上述病变均能成功显示病变部位及病变类型。结论应用多层螺旋CT容积再现技术及最大密度投影,再结合原始图像及多平面重建对于显示听骨链是否完整;锤、砧、镫骨有无部分缺失或肥大、细小;听骨链各部分间的连结及角度等的变化;听小骨破坏的程度和范围以及听小骨骨折、脱位、转位、移位等均有较明显的效果。

Objective To investigate the significance of three MSCT post-processing methods including volume rendering technique(VRT),maximum intensity projection(MIP)and multiplanar reconstruction(MPR)in diagnosis of conductive deafness.Methods A total of 70 patients with conductive deafness who were diagnosed and treated in our hospital from January 2011 to January 2019 who received temporal bone CT volume scan,with 0.625mm slice thickness,0.3mm slice overlap.All the CT scan images were reconstructed by means of bone algorithm.The unilateral target reconstruction images were acquired,then VRT,MIP,and MPR results were obtained by using post-processing work station.The ossicular chain in 70 patients with pathological changes was analyzed.Results Among the 70 patients with pathological changes of ossicular chain,40 cases were caused by congenital malformation of ossicular chains,which accounted for 57.1%,and 21 cases were caused by middle ear cholesteatoma,which accounted for 30%,and 9 cases were caused by middle ear trauma,which accounted for 12.9%.All the lesions mentioned above could be displayed successfully by VRT,MIP,and MPR,not only in confirmation of the lesion position,but also in characterizing the lesion.Conclusion By using VRT,MIP combined with MPR and original axial images,the variety of lesions of ossicular chain can be displayed effectively.