 We suggest that new MR techniques will make it possible to more accurately quantify the inflammatory burden within pCD. This will allow for better patient follow-up and more effective clinical decision making. Better medical management with more timely therapy onset, optimisation and cessation of therapy is needed. Moreover, although early data on therapeutic drug monitoring is emerging in luminal Crohns disease, similar data is lacking in pCD due to the lack of appropriate measures of disease activity. Improving MR methodology, by employing quantitative MRI to separate inflammation from fibrotic tissues, and to determine fistula size better will allow for the design and validation of a sensitive clinical scoring system. We will use the improved sensitivity of 3T to develop optimal imaging approaches and then use these results to tailor a convenient clinical score. We will determine whether this score can be used at both 3T and 1.5T. 