|UW mechanical engineers are developing a handheld |
microscope to help doctors and dentists distinguish between
healthy and cancerous cells in an office setting or
operating room. (Credit: University of Washington)
Surgeons removing a malignant brain tumor don't want to leave cancerous material behind. But they're also trying to protect healthy brain matter and minimize neurological harm. Once they open up a patient's skull, there's no time to send tissue samples to a pathology lab - where they are typically frozen, sliced, stained, mounted on slides and investigated under a bulky microscope - to definitively distinguish between cancerous and normal brain cells.
But a handheld, miniature microscope being developed by University of Washington mechanical engineers could allow surgeons to "see" at a cellular level in the operating room and determine where to stop cutting.
The new technology, developed in collaboration with Memorial Sloan Kettering Cancer Center, Stanford University and the Barrow Neurological Institute, is outlined in a paper published in the journal Biomedical Optics Express.
The handheld microscope, roughly the size of a pen, combines technologies in a novel way to deliver high-quality images at faster speeds than existing devices. Researchers expect to begin testing it as a cancer-screening tool in clinical settings next year.
For instance, dentists who find a suspicious-looking lesion in a patient's mouth often wind up cutting it out and sending it to a lab to be biopsied for oral cancer. Most come back benign.
That process subjects patients to an invasive procedure and overburdens pathology labs. A miniature microscope with high enough resolution to detect changes at a cellular level could be used in dental or dermatological clinics to better assess which lesions or moles are normal and which ones need to be biopsied.
|The real-time microscope |
images (left) illuminate similar
details in mouse tissues as
the images (right) produced
during an expensive,
multi-day process at a
clinical pathology lab.
(University of Washington)
The miniature microscope uses an innovative approach called "dual-axis confocal microscopy" to illuminate and more clearly see through opaque tissue. It can capture details up to a half millimeter beneath the tissue surface, where some types of cancerous cells originate.
The microscope also employs a technique called line scanning to speed up the image-collection process. It uses micro-electrical-mechanical - also known as MEMS - mirrors to direct an optical beam which scans the tissue, line by line, and quickly builds an image.
Imaging speed is particularly important for a handheld device, which has to contend with motion jitter from the human using it. If the imaging rate is too slow, the images will be blurry.
In the paper, the researchers demonstrate that the miniature microscope has sufficient resolution to see subcellular details. Images taken of mouse tissues compare well with those produced from a multi-day process at a clinical pathology lab - the gold standard for identifying cancerous cells in tissues.
The researchers hope that after testing the microscope's performance as a cancer- screening tool, it can be introduced into surgeries or other clinical procedures within the next 2 to 4 years.
Based on article originally posted by University of Washington.