Imaging Modalities for Perianal Crohn's Disease

Anorectal involvement by in Crohns disease (CD) causes perianal lesions that vary from simple and asymptomatic skin tags, to complex and disabling fistulas and abscesses. Perianal CD affects approximately one-third of patients; its management is difficult challenging and may require combined medical and surgical treatment, which has provend to give offer the best chance of success. An optimal preoperative disease assessment is needed crucial in order to provide achieve the bestan optimal results outcome and to avoid irreversible damages due to incomplete inadequateincomplete or inaccurate intervention. Imaging modalities are useful in order toto confirm diagnosis, to make a correct accurately classify classification of the disease, andas to plan the best most suitable treatment and to monitor its results. Endoscopic Ultrasonography (EUS) and pelvic Magnetic Resonance (MRI) are considered therepresent the best options from this perspective, both in terms of sensitivity and specificity, as well as for theirwith a demonstrated role in influencing managementtreatment approach. Transperineal Ultrasonography (TPUS) may be helpful when EUS is contraindicated or not-tolerated. Computed Tomography (CT) and fistulography are are generally no longer consideredabandoned because due to of their inferior performance and the radiation exposure they involve. All imaging should be done in conjunction with an Evaluation Under Anesthesia (EUA) made performed by an expert surgeon, to overachieve ensure accurate disease assessment. In this paper we review the available data regarding on each imaging modality, comparinge performances and focusing on specific pros and cons, in order to help assist clinicians in choosing thee most appropriate treatment and managementoption for each individual patient.