Emilio Quaia MD, Presenter: Nothing to Disclose

Michele Pontello, Abstract Co-Author: Nothing to Disclose

Gabriele Poillucci, Abstract Co-Author: Nothing to Disclose

Antonio Giulio Gennari, Abstract Co-Author: Nothing to Disclose

Maria Assunta Cova MD, Abstract Co-Author: Nothing to Disclose

To assess the value of time-intensity curves obtained after sulphur hexafluoride-filled microbubble contrast agent injection to identify predictors of response to pharmacologic treatment in patients with Crohn’s disease.

Twenty patients (12 male and 8 female; mean age ± SD, 45 years ± 6) with a biopsy-proven diagnosis of Crohn’s disease involving the terminal ileal loop were included in this prospective study. In each patient the terminal ileal loop was scanned by contrast-enhanced ultrasound 1 – 15 days before and 6 weeks after the beginning of specific pharmacologic treatment (azathioprine, infliximab, corticosteroids, or mesalazine). The quantitative analysis of echo-power after videointensity conversion in lineary arbitrary units was performed by a proprietary software package. In each patient the percent variation (Post–Pre x 100/Pre) of different semiquantitative parameters - peak enhancement, area under the time-intensity curve (AUC), AUC during washin (AUCWI), AUC during washout (AUCWO), rise time, time to peak enhancement, and mean transit time - were related to the therapeutic outcome assessed after 18 weeks from the beginning of pharmacologic treatment by CDAI and/or endoscopy (Crohn’s Disease Endoscopic Index of Severity).

Responders (n=11 patients) vs non-responders (n=9) differed in the percent variation of AUC (-56.9±15.45 vs 6.54±12.33, P<.05), AUCWI (-51.3±12.34 vs 10.33±7.55; P<.05), AUCWO (-72.21±55.05 vs -11.45±12.33, P<.05), and peak enhancement (-80.57±44,41 vs -5.43±12.22; P<.05) while did not differ in the percent variation of rise time, mean transit time, and time to peak enhancement. The AUC, AUCWI, AUCWO and peak enhancement are also independent predictors of response after multivariate logistic regression analysis.

The percent variation of the AUC, AUCWI, AUCWO and the peak enhancement after microbubble contrast agent injection are semiquantitative parameters which are different beweent responders and non-responders and are also predictors of response to pharmacologic treatment in patients with Crohn's disease.

Contrast-enhanced ultrasound is a simple, portable, and repeatable technique. The time-intensity curve obtained after microbubble contrast agent injection during patients' follow-up, may assess the effectiveness of the pharmacologic treatment in patients with Crohn's disease without the need to employ CT or MR enterography.

Quaia, E, Pontello, M, Poillucci, G, Gennari, A, Cova, M, Predictors of Response to Pharmacologic Therapy in Patients with Crohn's Disease Derived from Quantitative Analysis of Time-intensity Curves Obtained after Microbubble Contrast Agent Injection.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14003316.html