口服钆双胺注射液在小儿磁共振胰胆管成像中的应用

目的 观察口服稀释钆双胺注射液（欧乃影）作为小儿胃肠道阴性对比剂对改善磁共振胰胆管成像（MRCP）图像质量、提高胰胆管显示率的可行性。方法 对浓度为0.20%、0.30%、0.50%钆双胺稀释液与纯水同时行MR扫描,计算各浓度对比剂信号衰减率。将282例接受MRCP患儿分为观察组（244例疑似肝胆疾病患儿）和对照组（38例非肝胆疾病患儿）。检查前1 h嘱观察组患儿口服0.50%钆双胺稀释液400 ml,于45 min内摄入,15 min后进行检查。对所有图像进行评分,以评分≥3分不影响诊断为合格标准,计算图像质量合格率。采用Kappa系数检验2名医师评估图像质量结果的一致性,比较2组MRCP图像质量合格率,分析性别对图像质量合格率的影响。结果 浓度为0.20%、0.30%及0.50%钆双胺稀释液的信号衰减率分别为76.67%、88.47%及98.33%;0.50%钆双胺稀释液抑水效果最佳,故以0.50%钆双胺稀释液为小儿胃肠道阴性对比剂。2名医师对所有图像质量评分结果一致性强（Kappa=0.85,P<0.01）。观察组图像合格率（97.13%）显著高于对照组（47.37%,χ²=94.04,P<0.01）。不同性别图像合格率差异无统计学意义（χ²=0.01,P>0.05）。结论 口服浓度0.50%钆双胺稀释液可有效抑制小儿胃肠道液体高信号,改善MRCP图像质量。

Application of oral administration gadolinium diamine injection in MRCP in children

Objective: To explore the effect of oral administration of Gd-DTPA as a negative contrast agent on improving MRCP image quality in children. Methods: (1) In vitro experiment. We simultaneously scanned by "T2_spc" sequence with the Gd-DTPA diluent of 0.2%, 0.3% and 0.5% gadolinium diamine injection and pure water. The results showed that 0.5% GD-DTPA had the best water-inhibiting effect. Therefore, 0.5% GD-DTPA diluent of gadolinium diamine injection was selected for clinical experiment. (2) The experimental group: 244 patients treated from 2016 to 2017 were selected as the research subjects and received MRCP scan. The patient"s age ranged from 5 to 15 years. One hour before the examination, the patients began to take 0.5% GD-DTPA dilution 400ml orally and finished it in 45 minutes. And then the patients received MRCP scan after another 15 minutes. Examination images were scored by two senior pediatric radiologists. According to the number of T2 high signal in intestinal tract and its influence on diagnosis, the image quality was divided into 5 grades from 1 to 5 point. The qualified rate of image quality was calculated according to the criterion that the diagnosis was not affected by more than or equal to 3 points. (3) The control group: Thirty-eight children aged 5-15 years who underwent abdominal MRI for non-hepatobiliary reasons in our hospital from 2016 to 2017 were randomly selected for MRCP scanning. Scoring method and judging standard are the same to (2). Results: The pass rate of MRCP image quality (97.13%) in the experimental group was significantly higher than that in the control group (47.37%), P<0.05. The difference of MRCP signal intensity of two groups was statistically significant. Conclusion: Oral administration of GD-DTPA diluent with appropriate proportion of gadolinium diamine injection can significantly improve the effect of high signal intensity of intestinal fluid T2 in image background and help to improve the display rate of pancreaticobiliary duct in children.