Evaluatie van dynamische MRI als voorspeller van respons op behandeling in patienten met perianale fistels bij de ziekte van Crohn.

Background:
Crohn's disease (CD) is an inflammatory bowel disease (IBD). Perianal fistulas are reported to occur in up to 38% of patients. MR imaging is an effective imaging modality in the evaluation of patients with perianal CD as it can accurately demonstrate localization and extent of disease including clinically undetected fistula or abscess. Many patients with perianal Crohn's disease are treated with medicinal therapy. Clinical evaluation is inaccurate in determining treatment response. Initial studies have shown the potential of MRI in establishing the presence or absence of treatment response.

A recent study from our center (MEC number 04/271) has shown that dynamic contrast-enhanced MRI (DCE-MRI) before treatment can possibly add valuable, objective information about disease activity in perianal CD.


Objective:
To study whether dynamic MRI can predict treatment response and long term outcome in patients with Crohn's disease.


Study design:
Prospective observational study. We will study a cohort of consecutive patients with perianal Crohn's disease with DCE-MRI before and two times after remission induction therapy.


Study population:
Adult patients visiting the AMC IBD outpatients' clinic with proven CD and a draining perianal fistula.


Main study parameters/endpoints:
The main study endpoint will be the predictive value of DCE-MRI compared to PDAI.
Patients participating will undergo a MRI scan 3 times; which is a routine procedure in these patients. For this study a 5 minute additional MRI sequence will be performed during each MRI scan. Also patients have to give one additional venous blood sample and fill in the PDAI, a questionnaire, three times.

To study whether dynamic MRI can predict treatment response and long term outcome in patients with Crohn’s disease.

1. Before therapy (week 0): DCE-MRI, PDAI (question list) and CRP (laboratory value);

2. Week 12 after starting therapy: DCE-MRI, PDAI and CRP. One year after therapy: DCE-MRI and PDAI.

MRI before start therapy, after 12 weeks, after one year.