CT and MRI Evaluations in Crohn's Complications: A Guide for the Radiologist

  • Laura Maria Minordi
    Address correspondence to: L.M.M.
    Fondazione Policlinico Universitario A. Gemelli IRCCS, UOC di Radiologia Diagnostica e Interventistica Generale, Dipartimento di Diagnostica per immagini, Radioterapia Oncologica ed Ematologia. Largo Francesco Vito, 1 - 00168 Roma, Italia
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  • Antonio Bevere
    Università Cattolica del Sacro Cuore, Roma, Italia
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  • Alfredo Papa
    Università Cattolica del Sacro Cuore, Roma, Italia

    Fondazione Policlinico Universitario A. Gemelli IRCCS, U.O.C di Gastroenterologia, Roma, Italia
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  • Luigi Larosa
    Fondazione Policlinico Universitario A. Gemelli IRCCS, UOC di Radiologia Diagnostica e Interventistica Generale, Dipartimento di Diagnostica per immagini, Radioterapia Oncologica ed Ematologia. Largo Francesco Vito, 1 - 00168 Roma, Italia
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  • Riccardo Manfredi
    Fondazione Policlinico Universitario A. Gemelli IRCCS, UOC di Radiologia Diagnostica e Interventistica Generale, Dipartimento di Diagnostica per immagini, Radioterapia Oncologica ed Ematologia. Largo Francesco Vito, 1 - 00168 Roma, Italia

    Università Cattolica del Sacro Cuore, Roma, Italia
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Published:September 25, 2021DOI:
      Inflammatory bowel diseases (IBD) are a group of chronic inflammatory intestinal conditions with unknown etiology. Crohn's disease (CD) and ulcerative colitis (UC) are the two main types of IBD and they have some interchangeable and some different clinical and pathological characteristics. When diagnosis is performed for the first time, the majority of CD patients have a predominant inflammatory condition. As the disease progresses most patients experience the development of complications, such as abscesses, fistulas, perforation, strictures, and others. Both computed tomography (CT) and Magnetic Resonance Imaging (MRI) allow great view of the whole length of the intestinal tract together with the eventual extra-and intra-intestinal complications. MR enterography (MRE) and CT enterography (CTE), performed after oral administrations of contrast medium, have similar diagnostic accuracy for the diagnosis of CD and its complications. Even though CT is still the most familiar diagnostic technique used for studying CD worldwide, MRE have several important benefits that are leading to rapid increase in its employment in the last years. In particular, MRE allows a superior soft tissue contrast resolution compared to CT, offering a better visualization of bowel wall and its inflammatory and fibrotic characteristics. Moreover, Pelvic Magnetic Resonance is the principal technique in patients with perianal disease due to its ability of providing precise and fine detail images of the sphincter complex, which are crucial for evaluating pelvic disease. In this paper we describe common and uncommon complications in patients with CD, and explain how to identify their findings in CT and MR exams.

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