New Laser-Based Tool to Improve Accuracy of Brain Tumor Surgery
TEHRAN (Tasnim) – Scientists developed a new laser-based technology that could make brain tumor surgery much more accurate, allowing surgeons to tell cancer tissue from normal brain at the microscopic level while they are operating.
In a new paper, featured on the cover of the journal Science Translational Medicine, a team of University of Michigan Medical School and Harvard University researchers describes how the technique allows them to "see" the tiniest areas of tumor cells in brain tissue.
They used this technique to distinguish tumor from healthy tissue in the brains of living mice -- and then showed that the same was possible in tissue removed from a patient with glioblastoma multiforme, one of the most deadly brain tumors.
Now, the team is working to develop the approach, called SRS microscopy, for use during an operation to guide them in removing tissue, and test it in a clinical trial at U-M.
"Though brain tumor surgery has advanced in many ways, survival for many patients is still poor, in part because surgeons can't be sure that they've removed all tumor tissue before the operation is over," co-lead author Daniel Orringer said.
"We need better tools for visualizing tumor during surgery, and SRS microscopy is highly promising," he continues. "With SRS we can see something that's invisible through conventional surgical microscopy."
The SRS in the technique's name stands for stimulated Raman scattering. Named for C.V. Raman, one of the Indian scientists who co-discovered the effect and shared a 1930 Nobel Prize in physics for it, Raman scattering involves allows researchers to measure the unique chemical signature of materials.
In the SRS technique, they can detect a weak light signal that comes out of a material after it's hit with light from a non-invasive laser. By carefully analyzing the spectrum of colors in the light signal, the researchers can tell a lot about the chemical makeup of the sample.
A multidisciplinary team of chemists, neurosurgeons, pathologists and others worked to develop and test the tool. The new paper is the first time SRS microscopy has been used in a living organism to see the "margin" of a tumor -- the boundary area where tumor cells infiltrate among normal cells. That's the hardest area for a surgeon to operate -- especially when a tumor has invaded a region with an important function.
As the images in the paper show, the technique can distinguish brain tumor from normal tissue with remarkable accuracy, by detecting the difference between the signal given off by the dense cellular structure of tumor tissue, and the normal healthy grey and white matter.
