Intestinal ultrasonography in adults with Crohn's disease: a 2020 update.

In the last years intestinal ultrasonography (IUS) has increased its role in the management of inflammatory bowel diseases (IBD), that include Crohn's disease (CD) and ulcerative colitis. This is due to the fact that IUS is a non-invasive, inexpensive, and well-tolerated examination technique. Furthermore, it allows a real-time diagnosis with no radiation exposure. Usually, convex and linear probes with frequency between 3.5 and 12 MHz are used, also with the Color- Power Doppler. Focusing on CD, the IUS images of clinical interest are: bowel wall thickening (greater than 3 mm), pseudostratification and the wall vascularization. Moreover, IUS demonstrates inflammatory mass, loss of colonic haustration and the complications of the disease, such as stenosis, abscesses, and fistulas as well as other extraintestinal manifestations, such as lymph node enlargement and changes in the appearance of the mesenteric adipose tissue (creeping fat). Oral and intravenous contrast are used to obtain a better visualization of the bowel wall and to increase the diagnostic accuracy of IUS. In particular, intravenous contrast, administered during the procedure, allows to differentiate between active disease (bowel wall enhancement) and the fibrostenotic complications. Contrast-enhanced ultrasonography (CEUS) was proven to be useful in the follow-up and the disease recurrence detection. Beyond the support in the initial diagnosis, IUS has an important role in the follow-up of patients with CD, to monitor the response to the medical therapy and to detect possible complications. Furthermore, it can predict the recurrences after surgery, with more accuracy if Color-Doppler is used.

Power Doppler sonography to predict the risk of surgical recurrence of Crohn's disease.

PURPOSE: The aim of this work is to investigate the role of power Doppler sonography as an additional predictor of surgical recurrence in Crohn's disease. METHODS: A sample of 33 patients, with ileal or ileocolonic Crohn's disease, that had underwent intestinal resection, were retrospectively enrolled. All patients had bowel ultrasonography 7-16 months after resection. Power Doppler sonography of the preanastomotic ileum was evaluated as a possible prognostication tool to assess the risk of long-term need for reoperation. RESULTS: The absolute incidence of surgical recurrence in those who had a positive power Doppler was 42 %, while that of those who had a negative power Doppler was 28.6 %. Combining the power Doppler with bowel wall thickness, the surgical recurrence risk grew from 41.2 % of those with a positive power Doppler and thickness >3 mm to 55.6 % of those with a positive power Doppler and thickness >6 mm. CONCLUSIONS: Power Doppler look to be another useful prediction tool for the personalization of patient's care. It could be useful to perform power Doppler in all patients with a wall thickness >5 mm: for those who have a positive power Doppler it may be indicated as a more aggressive prophylactic therapy.

Role of bowel ultrasound as a predictor of surgical recurrence of Crohn's disease.

BACKGROUND: In Crohn's disease natural history, about 80% of the patients require surgery, which is not curative: unfortunately, the disease recurs in many patients. OBJECTIVE: To investigate the role of intestinal ultrasound to predict the risk of post-operative surgical recurrence in Crohn's disease. MATERIAL AND METHODS: A total of 196 patients, with ileal or ileocolonic Crohn's disease, undergoing intestinal resection, were retrospectively enrolled. All patients underwent bowel ultrasonography 6-15 months after resection. Wall thickness at the anastomosis level was measured, and thickening >3 mm was evaluated as risk factor of long-term need for reoperation. RESULTS: Patients who have a bowel wall thickness >3 mm have an risk ratio (RR) of surgical recurrence = 2.1 [95% confidence interval (CI) = 1.12-3.74] higher than those with a thickness of ≤3 mm. The absolute incidence of new surgical intervention is 13% in patients with thickness of 3 mm, 28% in patients with thickness >3 mm, 29,1% with thickness >4 mm, 34% with thickness >5 mm, and 40% with thickness >6 mm. CONCLUSIONS: Bowel wall thickness >3 mm at ultrasound may be a non-invasive predictor of early surgical recurrence after ileo-colonic resection.