Perianal Crohn’s disease (pCD) is a potential complication in CD. Absence of reliable disease measures makes disease monitoring unreliable. MRI is an effective imaging method for the evaluation of patients with pCD. Quantitative MRI sequences, such as diffusion-weighted image (DWI), and magnetization transfer (MT) offer opportunities to improve diagnostic capability. The aim of this study was to measure disease activity within a pCD patient cohort using quantitative MRI sequences (DWI and MT), at different field strengths, before and after biological therapy. The study is ongoing with patients presenting with a range of clinical and inflammatory markers of disease activity.