Short MRI scans combined with ultrasound to improve biopsy accuracy

Faster, cheaper and more accurate biopsy screening for breast cancer and other diseases could be made possible, thanks to a European-wide project.


The MRI and Ultrasound Robotic Assisted Biopsy (MURAB) project, led by Prof Stefano Stramigioli at the University of Twente in the Netherlands, is aiming to develop a system that can reduce the number of patients wrongly sent home with an all-clear.

Existing image-guided biopsies are typically carried out with the use of an ultrasound device. However, the imprecise nature of images produced with ultrasound means that the sample of tissue can sometimes be taken from the wrong place, according to Foad Sojoodi Farimani, a member of the project team at the University of Twente.

This results in a false negative rate of 10-20 per cent, he said. “So you either take a couple of biopsies, and have a false negative rate of 10-20 per cent, or you increase the number of biopsies taken, but this also increases the risk of complications,” he said.

In contrast, MRI scans are much more accurate, but can take up to 60 minutes to complete, and are too expensive to be used in widespread screening programmes, Farimani said.

So instead, the MURAB team want to combine the accuracy of a much shorter MRI scan with cheaper, real-time imaging.

“The patient would go into the MRI, for no more than around 15 minutes,” he said. “Then, using cheaper imaging sensors such as ultrasound, we would fuse the detailed, precise image of the MRI with that from the cheaper sensor,” he said.

The researchers plan to develop algorithms to fuse together information from the offline MRI images and real-time ultrasound into a single scan, to allow the suspicious tissue to be precisely located.

A tele-operated biopsy robot, controlled by the surgeon, would then be used to take a tissue sample, said Farimani.

The €4.3m project, whose members include Siemens and German robotics company Kuka, will also investigate the use of the technology in biopsies for muscle diseases. Ultimately though, it could be used to diagnose any disease where a biopsy is needed, said Farimani.

Meanwhile, Farimani and his colleagues are also working on an MRI-compatible robot, which could be used to carry out some procedures inside the scanner itself.