Inflamm Bowel Dis. 2020 Sep 18;26(10):1509-1523. doi: 10.1093/ibd/izaa218.

Mary-Louise C Greer ¹, Ruth Cytter-Kuint ², Li-Tal Pratt ³, Don Soboleski ⁴, Gili Focht ⁵, Denise A Castro ⁴

Author information

• ¹Department of Diagnostic Imaging, The Hospital for Sick Children; Department of Medical Imaging, University of Toronto, Toronto, Ontario, Canada.
• ²Imaging Department, Shaare Zedek Medical Center, Jerusalem, Israel.
• ³Pediatric Imaging Unit, Imaging Division, Sourasky Medical Center, Tel Aviv, Israel.
• ⁴Department of Diagnostic Imaging, Kingston Health Sciences Centre, Queen's University, Kingston, Ontario, Canada.
• ⁵The Juliet Keidan Institute of Pediatric Gastroenterology, Shaare Zedek Medical Center, Jerusalem, Israel.

Abstract

The number of imaging-based indices developed for inflammatory bowel disease as research tools, objectively measuring ileocolonic and perianal activity and treatment response, has expanded in the past 2 decades. Created primarily to assess Crohn's disease (CD), there is increasing adoption of these indices into the clinical realm to guide patient care. This translation has been facilitated by validation in adult and pediatric populations, prompted by simplification of score calculations needed for practical application outside the research environment. The majority of these indices utilize magnetic resonance imaging (MRI), specifically MR enterography (MRE) and pelvic MRI, and more recently ultrasound. This review explores validated indices by modality, anatomic site and indication, including for documentation of the presence and extent of CD, disease progression, complications, and treatment response, highlighting those in clinical use or with the potential to be. As well, it details index imaging features used to quantify chronic inflammatory activity, severity, and to lesser extent fibrosis, in addition to their reference standards and any modifications. Validation in the pediatric population of indices primarily developed in adult cohorts such as the Magnetic Resonance Index of Activity (MaRIA), the Simplified Magnetic Resonance Index of Activity (MARIAs), and the MRE global score (MEGS), together with newly developed pediatric-specific indices, are discussed. Indices that may be predictive of disease course and investigational techniques with the potential to provide future imaging biomarkers, such as multiparametric MRI, are also briefly considered.