Luboldt W, Steiner P, Bauerfeind P, Pelkonen P, Debatin J F
Institute of Diagnostic Radiology, University Hospital Zurich, Switzerland.
Radiology. 1998 Apr;207(1):59-65. doi: 10.1148/radiology.207.1.9530299.
To evaluate the performance of magnetic resonance (MR) colonography in the detection of colorectal mass lesions.
Twenty-three patients underwent MR colonography preceding colonoscopy. The colon was filled with a gadolinium-water mixture (1:100) with MR imaging guidance, and the patient was imaged prone and supine with a breath-hold three-dimensional spoiled gradient-recalled sequence. In addition, two-dimensional spoiled gradient-recalled images were acquired before and after intravenous administration of gadopentetate dimeglumine. Images were interactively analyzed on the basis of multiplanar reconstruction by two radiologists. For regions that were not conclusively assessable with multiplanar reconstruction, virtual intraluminal endoscopic images of the colon were reconstructed. MR findings were correlated with colonoscopic results.
Two patients were excluded from the analysis. Findings in eight of 11 patients were correctly assessed as normal and in six of 10 as mass-positive. In the four patients with false-negative findings, one had two 8-mm polyps and the other three had polyps smaller than 5 mm. All nine mass lesions larger than 10 mm, as well as four of the 10 polyps ranging between 5 and 10 mm, were detected, but all polyps smaller than 5 mm were missed. In contrast to the polyps less than 5 mm, the four missed polyps (5-10 mm) could be identified retrospectively on virtual intraluminal endoscopic images. Contrast enhancement was documented in 13 polyps.
Three-dimensional MR colonography provided virtual colonoscopic viewing and helped detection of colonic polyps.
评估磁共振（MR）结肠成像在检测结直肠肿块性病变中的性能。
23例患者在结肠镜检查前行MR结肠成像。在MR成像引导下，用钆水混合物（1:100）充盈结肠，患者在俯卧位和仰卧位屏气时采用三维扰相梯度回波序列成像。此外，在静脉注射钆喷酸葡胺前后采集二维扰相梯度回波图像。由两名放射科医生基于多平面重建对图像进行交互式分析。对于多平面重建无法明确评估的区域，重建结肠的虚拟腔内内镜图像。将MR检查结果与结肠镜检查结果进行对比。
两名患者被排除在分析之外。11例患者中有8例的检查结果被正确评估为正常，10例中有6例被评估为有肿块。在4例假阴性结果的患者中，1例有两个8毫米的息肉，另外3例有小于5毫米的息肉。所有9个大于10毫米的肿块性病变以及10个直径在5至10毫米之间的息肉中的4个均被检测到，但所有小于5毫米的息肉均未被发现。与小于5毫米的息肉不同，4个漏诊的息肉（5至10毫米）可在虚拟腔内内镜图像上进行回顾性识别。13个息肉有对比增强表现。
三维MR结肠成像提供了虚拟结肠镜检查视野，有助于检测结肠息肉。
