Anterior cruciate ligament (ACL) and other knee injuries are sometimes tricky to diagnose accurately because key components of the joint such as ligaments and tendons don’t show up well on MRI scans.
But that could change thanks to a new prototype mini MRI scanner being developed by UK researchers.
The team at Imperial College London say the device — which uses what’s known as the ‘magic angle’ effect — could potentially help diagnose knee injuries more quickly and more accurately.
“Knee injuries affect millions of people — and MRI scans are crucial to diagnosing the problem, leading to quick and effective treatment,” said Dr Karyn Chappell, a researcher and radiographer at Imperial’s MSK Lab. “However we currently face two problems: connective tissue in the knee is unclear on MRI scans, and people are waiting a long time for a scan.”
The brightness of tissues such as tendons and ligaments on MRI images depends on the angle between the collagen fibres and the magnetic field of the scanner, Dr Chappell explained. “If this angle is 55 degrees the image can be very bright, but for other angles it is usually very dark.”
The prototype scanner developed at Imperial can rotate around the leg and orientate the magnetic field in multiple directions, harnessing the magic angle to increase the brightness and to see how the collagen fibres are arranged.
What’s more, the small size of the device means that it could be used in local clinics and even GP surgeries, potentially reducing waiting times for MRI scans.
An animal study published in the journal Magnetic Resonance in Medicine confirmed that using the magic angle can accurately detect ligament and tendon damage.
The researchers now hope to progress to human trials of the mini scanner within a year, and to explore if the technology could also be used for other joints such as ankles, wrists and elbows.