ITS 2012 Report – Novel aspects in SPK transplantation: Contrast-enhanced ultrasound of pancreas transplants

by Maria Dalby – Contrast Enhanced Ultrasound (CEUS) can be used as an alternative to computerised tomography (CT) and magnetic resonance imaging (MRI) for post-operative imaging of pancreas transplants. With CEUS, perfusion of the pancreas graft can be visualised and necrotic areas identified, and it can also be used to guide targeted biopsies. Dr Stephan Kersting and his team at the University of Dresden have used CEUS in several pancreas transplant patients and their experience show that it is a useful tool for monitoring complications and aiding differential diagnosis.

The use of CEUS is not unique in transplantation medicine – it has been used for post-transplant surveillance of renal grafts for some time. However, pancreas transplants have so far proved more of a challenge to image using ultrasonography and instead CT scans and/or MRI have become the preferred option, at considerably greater inconvenience to the patient and higher provider cost. Having had extensive experience from using CEUS for diagnosing pancreatic cancer, Dr Kersting and his team decided to put the technology to use on pancreas transplant recipients as well.

To date, a total of 13 patients at the Dresden centre have undergone the CEUS procedure successfully, which involved routine CEUS on day 3 post-transplant and on the day before discharge, and also at any point when complications were suspected. The scan itself involved locating the pancreas graft in B-Mode and then assessing anastomoses in Duplex mode and perfusion in low-MI mode. In all 13 cases, the pancreas graft could be visualised in its entirety, with improved delineation and fully visible perfusion. There had been three cases of rejection – one humoral and two cellular – in these cases, CEUS had allowed the necroses to be visualised and quantified, with significantly prolonged absolute peak enhancement (dB) and time-to-peak (seconds) during histologically proven rejection episodes compared with normal tissue (14 seconds vs 5 seconds).

All 13 patients remained insulin-free at the time of presenting the data. Dr Kersting concluded that in the hands of experienced sonographers, CEUS is an efficient and sensitive tool for post-transplant surveillance of pancreatic grafts.

Stephan Kersting, University of Dresden, Germany