[MR enterography sequence evaluation for patients with Crohn's disease].

PURPOSE: To evaluate a routine MR enterography (MRE) protocol for patients with Crohn's disease (CD) in order to assess and rank the subjectively most important sequences regarding diagnostic decisions.

MATERIALS AND

METHODS

We prospectively examined 84 patients (42 male) with known CD using a coronal T2 / T1-weighted balanced SSFP (TrueFISP), axial T2-weighted single shot TSE (HASTE) as well as an axial T1-weighted gradient-echo sequence (2D-FLASH) before intravenous contrast application and a 2D-FLASH sequence with axial and coronal orientation after intravenous contrast application. 4 experienced radiologists subjectively evaluated the sequences independently using a scale between 1 and 5 (1 = excellent; 5 = non-diagnostic) regarding their diagnostic significance for a final radiologic decision. The ranking of the different sequences was statistically tested by the Friedman analysis.

RESULTS

The following ranking was found: HASTE sequences were ranked prior to contrast-enhanced axial gradient-echo (2D-FLASH). The third to fifth ranking was TrueFISP, the axial contrast-enhanced 2D-FLASH and the 2D-FLASH without contrast, respectively. Differences between the first and second rank were significant (p < 0.05), and all other differences were highly significant (p < 0.01).

CONCLUSION

The stable and fast T2-weighted MR sequences without intravenous contrast represented by axial HASTE and coronal TrueFISP were ranked as number 1 and 3. The examination protocol should be completed by a coronal T1-weighted gradient-echo-sequence after contrast injection, which can be supplemented by an axial acquisition. The T1-weighted gradient-echo sequence without contrast could be omitted.