This image of a human glioblastoma brain tumor in the brain of a mouse was made with stimulated Raman scattering, or SRS, microscopy. The technique allows the tumor (blue) to be easily distinguished from normal tissue (green) based on faint signals emitted by tissue with different cellular structures.
Intracranial cancers usually look the same as the healthy tissue surrounding them. With tumor resection in the brain, it is particularly important to remove the whole of the tumor while damaging as little normal brain matter as possible. A number of techniques exist for differentiating tumors, but each has its limitations.
Now researchers from University of Michigan Medical School and Harvard University are reporting that a new imaging technique they developed provides a fast and accurate identification of tumor tissue. The new imaging method relies on stimulated Raman scattering (SRS) microscopy, laser-based technique which doesn’t involve any labeling and can be used during an operation to guide the surgeon. The team performed studies using human and mouse brain tissue that had healthy and cancerous regions, and showed that the technique is ready for clinical testing.
From the study abstract in Science Translational Medicine:
SRS microscopy was able to differentiate tumor from nonneoplastic tissue in an infiltrative human glioblastoma xenograft mouse model based on their different Raman spectra. We further demonstrated a correlation between SRS and hematoxylin and eosin microscopy for detection of glioma infiltration (κ = 0.98). Finally, we applied SRS microscopy in vivo in mice during surgery to reveal tumor margins that were undetectable under standard operative conditions. By providing rapid intraoperative assessment of brain tissue, SRS microscopy may ultimately improve the safety and accuracy of surgeries where tumor boundaries are visually indistinct.
Study in Science Translational Medicine: Rapid, Label-Free Detection of Brain Tumors with Stimulated Raman Scattering Microscopy