Can MRI scanning tell us the severity of gut damage?

What the research looked at? 

There is evidence that blood supply to the bowel is reduced in Crohn's Disease, and that this may be one of the reasons why the bowel is damaged. 

When damaged sections of the bowels are removed during a resection in patients with Crohn’s, researchers have discovered abnormal blood vessels. They have also found new small blood vessels called ‘microvessels’ – it is thought that these may be generated to try and replace the oxygen that the damaged vessels are unable to supply. 

MRI scans can be used to measure the blood supply to the bowel using a technique called dynamic contract enhanced imaging. 

In this project, researchers wanted to investigate whether using MRI like this can help our understanding of how blood vessels are damaged in Crohn's. They also wanted to find out whether MRI scans could help identify those patients whose disease will quickly relapse after treatment. 

Conclusions: 

Researchers used MRI scans to measure the blood supply in sections of the bowel before patients underwent resections. Then after the bowels had been removed, they carried out tests on the tissue. They were looking for chemicals produced when tissue is short of oxygen. 

They concluded that these chemicals were more prevalent in patients with Crohn's. They also found that these chemicals were high in the tissues of people whose MRI scans showed that they had a low blood supply to this area. This supports the theory that an abnormal blood supply to the bowel causes a lack of oxygen, and stimulates the growth of the new abnormal microvessels. It also suggests that MRI scans can detect this process - and could be used to monitor drugs designed to treat the lack of oxygen. 

However, the researchers were unable to show than measuring blood supply by MRI can predict which patients will relapse – but they did find that there was a suggestion of lower blood supply in patients which did relapse. More research is needed to be carried with a large number of patients to test this. The researchers found that the radiologists were able to identify disease activity from normal MRIs, but the dye-guided analysis could not highlight disease activity. Nor could the dye-guided MRI predict relapse. The researchers concluded more investigation was needed. 

What do researchers think this could this mean for people with IBD? 

The researchers’ work supports the theory that the abnormal blood supply to the bowel causes a lack of oxygen and this stimulates new abnormal microvessels. Their work suggests MRI can detect this process and may be of use in monitoring drugs designed to treat the lack of oxygen. 

Who led the research: Prof Stuart Taylor, University College Hospital 
Our funding: £28,999 over 24 months 
Official title of the application: "Magnetic Resonance Imaging derived mural perfusion dynamics in Crohn's Disease: Pathophysiology and prediction of disease relapse."
Tags: Investigations