Use and Misuse of CT and MR Imaging in IBD

1. Use and Misuse of CT and MR Imaging in IBD David H. Bruining, MDMayo Clinic, Rochester, MN bruining.david@mayo.edu

2. Disclosures Consulting • Bracco • Avantis Research Support • Janssen Biotech • Given • Genentech

3. Discussion Points What is known/standard of care • Benefits of Imaging • CTE and MRE performance Appropriation / inappropriate applications • How are we doing? • New developments

4. Symptoms Aren’t Enough Correlation coefficients (bolded) were significant; P<0.05; n=164 CDAI; Crohn’s disease activity index: SES-CD; simple endoscopic core for Crohn's disease Jones et al: Clin Gastroenterol Hepatol, 2008

5. CT and MR EnterographySimilar Performance to CTE for Identifying Active Disease MRE CTE Siddiki et al: Am J Roentgenol, 2009

6. CT and MR Enterography Advantages – CTE • Less interobserver variability • Higher image quality • Shorter image acquisition times • Cost • Access • Bone assessments Advantages – MRE • No radiation • Multiple phases • Detection of fibrosis • MRI superior for perianal disease • Pregnancy • Renal insufficiency

7. Appropriate UseRight Test for the Right Patient

9. Use of CT and MR Enterography in Crohn’s Disease Suspected Crohn’s disease • Establish disease • Determine optimal strategy for endoscopic confirmation (BAE) • Define extent and severity • Exclude alternate etiologies • Penetrating and stricturing complications • Extra-intestinal disease manifestation Established Crohn’s disease • Response to treatment • Surgical planning • Exclude alternate etiologies • Penetrating and stricturing complications • Extraintestinal disease manifestation • Bone health interrogations

10. Lesion Remodeling on CTE 6/18/2007 9/26/2005 6/7/2004* *Infliximab initiated in 2004 after examination

11. CTE Generated Finite Element ModelBone Strength Density distribution Regions of failure Weber et al: DDW, 2013

12. When and How to Image Established disease • Disease activity • Disease extent • Disease severity • Evaluate for penetrating disease • Surgical planning • Assess response to therapy Suspected disease • Establish diagnosis • Exclude alternate or additional etiologies for patient symptoms • Postoperative • SBFT (complex) • Occult stricture • Enteroclysis • Other • VCE and ultrasound MRE • Age <35 years • Serial examinations • Renal disease • Pregnancy • Stricture • Perianal disease CTE

13. Misuse of CT and MR Enterography Wrong test • Multiple CTEs in young patient (MRE) • MRE in elderly (CTE) • CTE or MRE for dysplasia (colonoscopy) • MRE for inpatient with sepsis/SIRS, tremor, obese, diabetics (CTE) • CTE in patient with renal insufficiency or pregnancy (MRE) Wrong patient • Chronic abdominal pain with multiple negative CT or MR examinations

14. Emergency Medicine and IBD POA; perforation, obstruction, abscess: POANCD; POA + non-CD urgent Kerner et al: Clin Gastroenterol Hepatoll, 2012

15. Can We Do Better? • Several models in development for ED triage • APON Risk Score • APON: Abscess, perforation, obstruction, new or worsening non-CD urgent findings • Final model variables: History of obstruction, history of intra-abdominal abscess, current hematochezia and WBC >12,000/µL • Score subtracts 1 for hematochezia and adds 1 point for others • APON risk score -1 is associated with low risk Kerner et al: Inflamm Bowel Dis, 2013

16. Summary • Cross-sectional imaging • Objective measure of disease activity • Detects penetrating disease and extraintestinal manifestations • Alters management plans • Appropriate use • Applications continue to expand • Key is to match right patient with right exam

17. Future Research • Fine-tuned predictive models – acute presentations • Widely available ED tool • Simple • Role of ultrasound • Standardized imaging algorithms, guidelines and reporting lexicon