01 Nov 24. PET/MRI study provides hope for vasculitis treatment

Having been healthy all her life, Catherine had begun experiencing an array of unpleasant symptoms including fatigue, headaches, loss of appetite, and night sweats. Investigations by several doctors showed no clear cause. Eventually Catherine was given a tentative diagnosis of large vessel vasculitis (LVV) – a condition that involves inflammation of the blood vessels.

Catherine was referred to participate in Dan and Bean's study, which was investigating whether a combination of PET and MRI scanning could be used to monitor LVV disease activity and assess response to treatment. This is crucial, because failure to treat LVV carries a risk of serious complications such as strokes or aneurysms, but the primary treatment for LVV – with steroid medication – can also cause severe side-effects including vision loss, gastric ulcers, and gastrointestinal bleeding, as well as depression from long- term use. As Dan sums it up: "We want to give just the right amount of treatment, and no more."

Catherine's initial PET/MRI scan clearly showed active LVV. She was then treated with high-dose steroid medication, and in line with the study protocol she returned for a follow- up PET/MRI scan after six months. This scan showed near total resolution of disease activity, allowing her to reduce her steroid dose with confidence. This underscores the importance of the new technology of PET/MRI scanning in helping clinicians to track the disease and provide more targeted treatment.

Dan, Bean, and colleagues published the results of their study in Nature Communications in August. They conclude that PET/MRI is useful in tracking disease activity and assessing treatment response, and that larger studies are now warranted. Currently, PET/MRI scanning is not available freely on the NHS, and the scanner at the University of Edinburgh is the only one in Scotland. However, there are several in England and the popularity of the technology is growing.

Read the paper in Nature Communications

Keywords:

• large vessel vasculitis 
• PET
• MRI