螺旋CT多种显示方法对结直肠肿瘤诊断价值的对比研究

Diagnostic value of multiple multi-slice spiral CT colonography for colorectal tumors after postprocessing

目的对比研究16层螺旋CT结肠成像的多种显示方法在结直肠肿瘤诊断中的价值。方法对42例结直肠肿瘤病例作16层螺旋CT扫描,将原始横断面图像以及在工作站经后处理技术获得的多平面重建(multiplanar reform ation,MPR)、表面遮盖显示(shaded surface display,SSD)、透明显示(Raysum)、CT仿真结肠镜(CT virtual colonoscopy,CTVC)、管壁显示(Wall View)和全景平铺显示(virtual dissection,VD)图像,按病变长度、累及肠壁周径和分型3方面进行分析比较。病变均经结肠镜和/或手术病理结果证实。结果对病变长度的显示,Wall View、SSD和Raysum的符合率(分别为97.6%、95.2%、95.2%)都高于CTVC(78.6%)和横断面(73.8%);对病变累及肠壁周径的显示,VD的符合率(100%)高于CTVC、SSD、Raysum和横断面(分别为85.7%、80.9%、80.9%、78.6%);对病变分型的显示,CTVC的符合率(90.5%)高于SSD、Raysum和VD(分别为71.4%、71.4%、61.9%);Wall View的符合率(88.1%)高于VD(61.9%)。结论CT结肠成像的7种不同显示方法对结直肠肿瘤的诊断各有优劣,合理的选择成像方法并联合运用能提高诊断的准确性。

Objective To evaluate the diagnostic value of several 16-slice CT colonography （CTC） for colorectal tumors. Methods Forty-two patients with colorectal tumors underwent transverse scan using 16-slice spiral CT. The size, the circumferential extension and the pathologic patterns of tumors were compared among the images obtained by different techniques, including the original transverse images, the images of the multiplanar reformation （ MPR）, shaded surface display （ SSD）, Raysum, CT virtual colonoscopy （ CTVC ）, Wall View and virtual dissection （VD）, most of which were obtained from the postprocessing in the workstation. All the tumors were confirmed by the conventional colonography （CC） and/or histologically. Results The correction rates of the tumor size evaluation by Wall View, SSD and Raysum （97.6%, 95.2%, 95.2% ） were higher than CTVC （78.6%） and original transverse images （73.8%）. The correction rate in evaluating the circumferential extension of colorectal tumors by VD （ 100% ） was higher than by CTVC, SSD, Raysum and original transverse images （85.7%, 80.9%, 80.9%, 78.6% ）. The correction rate in evaluating the pathologic pattern by CTVC （90.5%） was higher than by SSD, Raysum and VD （71.4%, 71.4%, 61.9% ） ; Futhermore, that by Wall View （88.1% ） was higher than by VD （61.9%）. Conclusion Seven display methods of CT colonography have their own advantages and disadvantages in diagnosis of the colorectal tumors. Proper choice of display methods and their combination can improve the diagnostic accuracy.