OBJECTIVETo evaluate the application of low-dose CT enterography with adaptive iterative dose reduction(AIDR) technique in diagnosing Crohn's disease.

METHODSRetrospective 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.

RESULTSThe 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.

CONCLUSIONCT 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.