Surgical tumor removal, particularly within the breasts, suffers from imprecision related to identifying the margins of where the tumor is. That’s because tumors are often indistinguishable from healthy tissue until they’re visualized and analyzed by pathologists using laboratory microscopes. The time it takes to confirm that sampled tissue is clear of cancerous cells takes longer than a person can stay open and under anesthesia, so the final word usually comes in only after the patient has been stitched up and so too often leads to revision surgeries.
Researchers at the University of Washington have now developed a microscopy system that may provide imaging of tumor margins within about a half hour, short enough to be used intraoperatively and hopefully resulting in clean, complete excisions that don’t lead to additional procedures.
The new device is a light-sheet microscope that images tissue without damaging it. This allows the tissue to be sent for further analysis, such as to review its molecular and genetic content, that can confirm the findings established via microscopy.
Light-sheet microscopy illuminates the tissue in slices, each slice being imaged individually. The data can be stitched together to produce volumetric images that can be navigated similar to how radiologists look at CT scans. Seeing the 3D structure of the tissue examined helps to establish its nature as being cancerous or not.
Because the slicing is done with light rather than actually physically creating slices and positioning them on glass slides, the process is quick and not too tedious.
There’s still a good deal of effort that can be applied to improving this technique to produce better, faster images. Lots of this will involve composing better algorithms that combine the imaging data into a comprehensive whole.
This comparison shows images of breast tissue taken by the open-top light-sheet microscope (left), traditional pathology techniques (middle) and frozen sectioning during surgery (right). The first two images reveal crisp details of cellular and nuclear features, while the frozen-section image is distorted due to the challenges of freezing fatty breast tissues. While the formalin-fixed paraffin-embedded section requires hours of preparation, the light-sheet microscope image is captured in minutes.Glaser et al./ Nature Biomedical Engineering
Here’s a University of Washington video touting the new technology:
Study in Nature Biomedical Engineering: Light-sheet microscopy for slide-free non-destructive pathology of large clinical specimens…