New ultrasound scan ensures doctors remove all cancerous tissue during brain surgery

International researchers are touting a new type of ultrasound scan for its potential to guide complicated brain tumor surgery and improve patient outcomes, according to a study published Monday.

When tested against 2D ultrasound and surgeon’s opinions, shear wave elastography was better at detecting lingering tumor tissue during invasive brain procedures. It was, however, less accurate at spotting those without residual cancerous tissue, researchers reported in Frontiers in Oncology.

This means the novel technique could produce more false positives compared to surgeons and should be used to guide opinions rather than replace them altogether, study lead Jeffrey Bamber, a professor at the Institute of Cancer Research, London, explained.

"Ensuring all of a brain tumor is removed without damaging healthy tissue is a major challenge in brain surgery,” Bamber added in a statement. “Using this new type of scan, surgeons could greatly increase confidence that no cancerous tissue is going to be left behind after surgery.”

Shear wave elastography works by measuring stiffness and stretch within tissue, with vibrations moving faster through stiffer tissue. And while MRI is considered the most accurate modality for detecting residual cancer, it’s also expensive and lengthens surgeries by two hours, the authors explained.

Bamber et al. put sheer wave to the test in 26 patients, taking such scans and 2D ultrasounds during brain surgery, as well as before, during, and after removing the tumor. Surgeons were asked to spot potentially cancerous tissue before looking at the imaging results.

Overall, elastography performed well, detecting tumors with 94% sensitivity compared to 73% for ultrasound and 36% for surgeons. The new technique did fall short of the surgeons’ 100% specificity, only reaching the 77% mark. Ultrasound, meanwhile, reached 63%.

The authors did report shear wave elastography was just as good as post-surgery MRI at spotting cancerous tissue left behind after procedures.

“This new study has shown for the first time that a particular type of ultrasound scan could provide real-time guidance to brain surgeons during operations as they choose which tissue to remove,” Kevin Harrington, head of the Division of Radiotherapy and Imaging at the Institute of Cancer Research, London, added. “It's an exciting area of research which has the potential to improve outcomes for patients by ensuring surgeons take out the entire tumor while minimizing damage to the healthy brain."