口服甘露醇多层螺旋CT小肠造影的临床价值

Clinical value of multislice CT enterography with isosmotic mannitol as oral contrast

目的评价口服大剂量2.5%等渗甘露醇多层螺旋CT小肠造影(multisliceCT enterography,MSCTE)的可行性和临床价值。方法21例志愿者、91例疑有小肠病变患者每人口服约1500ml2.5%等渗甘露醇后,静脉注入20mg山莨菪碱注射液,随后行多层螺旋CT三期扫描,并在Wizard工作站上进行多平面重建(multiplanarreformation,MPR)、最大密度投影(maximumintensity projection,MIP)和容积重建技术(volumerenderingtechnique,VRT)重建。将正常组小肠分为十二指肠、空肠和回肠三部分,测量了各段小肠的管径和肠壁强化程度,并分别以0、1、2、3分表示适度充盈的肠段部分占所评估肠段的30%以下,30%～50%以下,50%～80%以下和80%以上。分析不同小肠病变的MSCTE表现,并比较了其中24例小肠插管造影与MSCTE的诊断结果。结果所有受试者均认为等渗甘露醇微甜,易接受,未发现并发症。十二指肠、空肠及回肠的充盈度分别为2.52、2.33和2.81分;MSCTE清楚地显示了肿瘤、Crohn病、粘连性肠梗阻等多种小肠疾患的肠内、肠壁、肠外血管、系膜及腹内脏器情况;MSCTE检查与临床诊断符合率为95.6%(87/91),而小肠插管造影的诊断符合率为87.5%(21/24)。结论MSCTE是1种简便、易行、经济实惠、能全方位、多维显示小肠疾病的方法。

Objective To assess the feasibility and usefulness of multislice CT enterography (MSCTE)with orally administered isosmotic mannitol (2.5%) as negative contrast in demonstrating normal and abnormal small bowel. Methods Twenty-one volunteers and 91 patients suspected of various kinds of small intestinal diseases were examined. About 1500 ml isosmotic mannitol as oral negative contrast agent was administered and then 20 mg of Raceanisodamine hydrochloride was injected intravenously. Helical CT scanning on a Siemens Sensation 16 scanner was performed 5 to 10 minutes later. All volunteers and patients were interviewed on their tolerance of the procedure. Imaging data were post-processed with multiplanar reformation(MPR), maximum intensity projection(MIP), and volume rendering technique(VRT), and then interpreted by two radiologists. Adequacy of luminal distention of duodenum, jejunum, and ileum was assessed with a four-point scale, respectively, in which a distention score of 0, 1, 2, and 3 represented less than 30%, 30%-50%, 50%-80%, and more than 80%, respectively of the evaluated segments. The maximum outer diameters of duodenum, jejunum, and ileum were measured and the CT values of bowel wall in different phases were measured with a ROI of 2 mm 2. Demonstration of features of various kinds of small bowel diseases was analyzed by comparing with the results of conventional enteroclysis in 24 patients, and the diagnostic efficacy of MSCTE was evaluated. Results The taste of isosmotic mannitol was good (slight sweet) and acceptable by all. Luminal distention score was 2.52, 2.33, and 2.81 in duodenum, jejunum, and ileum, respectively. CT features of many kinds of small bowel diseases such as tumors, Crohn′s disease, and postoperative adhesion, etc. were clearly displayed, including mass, luminal stenosis or dilatation, wall thickening, mural enhancement, mesenteric fibrofatty change, mesenteric vasculature change, enlarged lymph nodes, and so on. The clinical diagnostic coincidence of MSCTE was 95.6%(87/91), while the accuracy of conventional enteroclysis was 87.5% (21/24). Conclusion MSCTE with isosmotic mannitol as negative contrast for distending the small bowel is a simple, rapid, noninvasive, and effective method for evaluating small bowel diseases.