P1.33: Is there a role for ultrasound in the evaluation of graft small bowel?

Abstract

Introduction: Intestinal graft recipients are subjected to often significant doses of radiation. MRI studies may not be feasible acutely. Endoscopic examination of the intestine is usually limited to small sections of the graft. Ultrasound (US) is an established technique in the evaluation of disease extent in patients with small bowel Crohn’s. We have utilised US for several years to evaluate the graft small bowel and have retrospectively reviewed our findings. Methods: This is a retrospective review of small bowel US studies performed post operatively for our cohort of 97 patients receiving an intestine-containing graft between 2007 and 2019. Imaging interpretation was made on the basis of grey-scale images and Doppler imaging. US images were reviewed with subsequent clinical, imaging, endoscopy and histology findings Results: 97 patients received an intestine-containing transplant between 2007 and 2019. There were 45 US studies undertaken in 27 patients. The majority of studies (23 studies in 9 patients) were undertaken in those with biopsy-proven acute cellular rejection (ACR). Imaging findings of mural thickening, loss of mural stratification, reduced peristalsis and mesenteric hypervascularity were observed in 7 patients with ACR. 2 patients with a history of ACR had normal US appearances at follow up, which correlated with endoscopic findings of recovery. Of the US performed for ACR, concurrent endoscopy (within 1 week) occurred in 11 US studies. 8 endoscopies demonstrated features related to rejection confirmed at histology. 3 demonstrated recovery. 5 patients underwent US immediately post surgery with normal findings consistent with concurrent CT or endoscopy findings. 17 US studies were undertaken for 12 patients for a range of clinical indications: 5 studies were normal, 4 consistent with clinical / imaging findings. 1 patient had drug related ulceration at endoscopy. 11 studies in 6 patients demonstrated minimal mural thickening but no further features to suggest rejection, 4 were followed with endoscopy with no features of rejection. The remainder were followed clinically and radiologically. 1 US demonstrated features suggesting rejection but normal endoscopic findings. An internal hernia was found at surgery. Conclusion: Small bowel US is a useful technique in establishing normal appearances of the bowel. When interpreted in conjunction with clinical and endoscopic findings in patients with ACR it may have a potential role in surveillance.