多层螺旋CT三维重建对胃癌术前分期的价值

目的:通过对胃癌患者实施多层螺旋CT（multi-slice spiral computed tomography，MSCT）及三维重建后进行术前分期,评价其准确性及对胃癌治疗方式选择的价值。方法:2010年8月-2011年10月在中国医科大学附属盛京医院胃肠、营养外科住院，并经术前胃镜及病理检查确诊的胃癌患者64例。全部患者在术前一周内进行64层螺旋CT平扫及双期增强扫描，将获得的扫描影像数据以1.0 mm薄层重建后传至后期工作站。由2名从事腹部CT工作5年以上的高年资影像科医生应用工作站软件对图像作多平面重建（multi-planar reformations，MpR)。再由1名从事腹部CT工作5年以上的高年资影像科医生和1名高年资胃肠外科医生在不明了胃镜结果的情况下在PACS上通过协商读片，分别分析MSCT横断位及MpR图像。对照手术后的病理结果，计算MSCT横断位和MpR图像对胃癌的检出率和T、N分期的准确性；比较MSCT横断位和MpR图像对胃癌T、N分期准确性。结果:对原发胃癌病灶的检出率，MSCT横断图像和MpR图像分别是90.63%(58/64)和95.31%(61/64)。与组织病理学分期比较，依据MpR图像的T分期准确率为85.25%(52/61)，高于依据MSCT横断位图像的65.57%(40/61)(P=0.012)；而MpR图像的N分期准确率为73.77%(45/61)，与MSCT横断位图像的67.21%(41/61)比较，其差异无统计学意义(P=0.427)。结论:MSCT横断位结合MpR图像能更清晰显示肿瘤形态、大小以及与邻近结构的关系，能较为全面和准确地观察胃癌淋巴结的位置、大小及数量，更好地进行术前分期，有助于胃癌治疗方式的选择。

Study of the value of multi-slice spiral computed tomography with three-dimensional reconstruction in preoperative staging of gastric cancer

Objective:To evaluate the accuracy of multi-slice spiral computed tomography（MSCT）with three-dimensional reconstruction in the preoperative staging of gastric cancer，and its benefit to choice of therapeutic modality of gastric cancer.Methods:Sixty-four patients with gastric cancer proved by endoscopic biopsy in the Gastrointestinal and Nutritional Department of Shengjing Hospital Affiliated to China Medical University were collected into this study from August 2010 to October 2011.All the patients underwent MSCT in a preoperative week and all of the data sets were transmitted to workstation after being reconstructed in 1-mm section and 1-mm interval.Two radiologists with over 5 years experience took the charge of dealing with the data sets for multi-planar reconstruction（MpR).Furthermore,it was analyzed by 1 experienced radiologist and 1 experienced generalsurgeon majoring in transverse and MpR images.Evaluate the depth of tumor invasion（T staging) and regional lymph node involvement（N staging).MSCT findings were compared with pathologic results which served as the reference standard.Sensitivity,specificity and accuracy were also assessed.Results:Detection rate of primary tumors with transverse and MpR images were 90.63%（58/64) and 95.31%（61/64),respectively.The accuracy for MpR images in assessment of tumor invasion of the gastric wall（T staging) was 85.25%（52/61)，which was higher than that for transverse images［65.57%(40/61)］（P=0.012).Overall accuracy for lymph node（N) staging was 73.77%（45/61) with MpR images and 67.21%（41/61) with transverse images,respectively.This difference was not statistically significant（P=0.427).Conclusion:MSCT with MpR can show the shape and size of the tumor more clearly,accurately evaluate depth of tumor invasion of the gastric wall and peripheral gastric fat plane infiltration,identify a thin fat plane between a tumor and adjacent organs,observe accurately the location,size and number of peripheral gastric lymph node and better differentiate lymph nodes from small peripheral gastric vessels,which can benefit preoperative staging and choice of therapeutic modality of gastric cancer.