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:螺旋CT 容积扫描和计算机仿真技术的结合产生了CT 仿真内窥镜成像技术.对此技术在胃肠道应用中的操作方法、扫描条件选择、病人检查前准备、图像分析、发现病灶的敏感性和特异性、以及与纤维内窥镜比较的优越性和局限性均有学者研究.目前的研究认为1 、胃CTVE 检查,可得到类似光学纤维镜所见的胃腔内表面轮廓,还可结合横断图像观察病变对胃外浸润的情况,病人无痛苦,检查无盲区,因此,胃CTVE 具有取代钡餐检查的可能.2 、小肠CTVE 检查是可能的,对大小4 M M 以上的病变有较高的可信度,但其临床意义尚有待进一步研究.3 、CTVE 有利于发现患者结肠内0 .5CM 以上的隆起息肉.作为非侵入性的方法,结肠CTVE 检查安全、快捷、病人无痛苦.因此,结肠CTVE 有望成为结肠、直肠息肉理想的普查工具.虽然此技术目前尚处于初级阶段,但已显示了其在医学教育、影像诊断及减少侵入性治疗诸方面的巨大潜能.该文结合文献和作者有限的经验,就此技术的原理、方法及临床应用的价值和局限性作一介绍.“,”The combination of computed virtual techniques and CT volume scan has resulted in a new imaging technique - CT virtual endoscopy. The technique of gastrointestinal CT virtual endoscopy is reconstructing multiple three-dimensional projection images of inner wall along the longitudinal path of gastrointestinal tract, and making these images larger and larger gradually and playing them back in the form of a cinematic loop or movie format that simulates conventional endoscopic view. During the image-processing customized computer innovative software is used to adjust the volumetric imaging data acquired in a single helical CT scan. The large lesion of the stomach can be showed by CT virtual gastroscopy as the same results as barium meal examination done. But the role of CT virtual gastroscopy in early gastric carcinoma is still obscure. More studies on it should be done in future. Detection of 4mm lesions is highly reliable with virtual endoscopy of the small bowel, but its clinical relevance remains to be assessed in future studies. CT virtual colonoscopy is feasible for the detection of colorectal protrusive polyps that are 5.0mm in diameter. Moreover, CT virtual colonoscopy offers several advantages over conventional colonoscopy, including the ability to detect abnormalities proximal to obstructing carcinomas, accurate localization of abnormalities within the colon,and good patient tolerance. Therefore, CT virtual colonoscopy may play an important role in future diagnosis of coloretal cancer and screening patient at risk. The values and limitations about clinical applications of gastrointestinal virtual endoscopy are summarized in this article.