自适应迭代降剂量技术在克罗恩病CT小肠造影中的临床应用

目的 评价自适应迭代降剂量（AIDR）技术在克罗恩病CT小肠造影中的应用.方法 回顾性分析2013年1-3月间中山大学附属第六医院收治并经炎性肠病多学科诊疗小组确诊为克罗恩病的26例患者的临床和影像资料,所有病例均采用AIDR技术行CT小肠造影检查.由两名诊断克罗恩病经验丰富的放射科医生分别阅片,计算每例患者所受电离辐射总量,并分析克罗恩病影像学特点.结果 26例患者辐射剂量为5.58～12.90（9.00±2.00） mSv,明显低于常规使用剂量（15 mSv）.克罗恩病CT小肠造影检查发现,26例患者中,1例患者处于静止期,另外25例共出现109处节段性肠壁增厚,合并系膜侧淋巴结肿大,同时出现异常强化现象.其中16例发现肠腔狭窄,12例肠壁呈分层样强化,14例出现“梳样征”;8例出现系膜侧脂肪密度增高,7例肠瘘,6例腹腔脓肿,3例肛瘘.结论 低剂量AIDR技术CT小肠造影技术不会损失图像质量,能够有效诊断克罗恩病并明显降低辐射剂量.

Application of adaptive iterative dose reduction technique in CT enterography in diagnosing Crohn disease

Objective To evaluate the application of low-dose CT enterography with adaptive iterative dose reduction （AIDR） technique in diagnosing Crohn＇s disease Methods Retrospective analysis was performed on 26 patients diagnosed as Crohn＇s disease by the multidisciplinary team in our hospital.Low-dose CT enterography with 640-slice MDCT was performed on these 26 patients using adaptive iterative dose reduction （AIDR） technique.Characteristics of Crohn＇s disease in CT enterography images were independently analyzed by two radiologists who were experienced in Crohn＇s disease with calculating the total radiation dosage.Results The radiation dosage of 26 patients ranged from 5.58 to 12.90 mean（9.00±2.00）] mSv,which was lower than conventional scan （around 15 mSv） known from the literatures.According to the images of CT enterography of 26 cases,bowel wall thickening with abnormal enhancement and lymphadenectasis were found in 25 cases with total 109 segmental bowel wall thickening.Among 25 thickening cases,enterostenosis was found in 16 cases,stratification enhancement in 12 cases and comb sign in 14 cases.Besides,it was found that 8 cases with hyperdense fat on the mesenteric side,7 cases with intestinal fistula,6 cases with abdominal cavity abscess,and 3 cases with anal fistula.Conclusion CT enterography of Crohn＇s disease with adaptive iterative dose reduction technique is an effective method to evaluate Crohn＇s disease without compromising image quality with reduced radiation dosage.