Optimal b value of diffusion-weighted imaging on a 3.0T magnetic resonance scanner in Crohn’s disease

Figure 2 Images obtained in a 34-year-old man. There was high signal intensity in the sigmoid colon and rectum when b value 800 s/mm² (A) was chosen. But when b value 1500 s/mm² to 2500 s/mm² (B-D) was chosen, the high signal was apparently depressed. It was confirmed that the sigmoid colon and rectum were normal by colonic endoscopy.

Figure 1 Diffusion-weighted imaging images obtained in a 28-year-old man. The whole colonic inflammation was identified by endoscopy. The high signal intensity of colonic liver flexure and splenic flexure could be recognized on b = 800 s/mm² (A) and b = 1500 s/mm² images (B). But when b = 2000 s/mm² or b = 2500 s/mm² (C and D) was chosen, the signal intensity was depressed and these two segments were misdiagnosed as negative.