A Lens-free Microscope That Could Detect Cancer

These days, most cell-level abnormalities such as a cancer and other malignant tumors often require costly high powered optical microscopes to diagnose.

That may change, however, as researchers from UCLA are developing a lens-free microscope that can be used to detect these malignant abnormalities with the same accuracy as their larger, more expensive counterparts.

The lens-free microscope is one of the latest developments in a series of computational imaging and diagnostic devices developed at the UCLA Henry Samueli School of Engineering and Applied Science. The microscope was developed in the lab of Aydogan Ozcan, a professor of electrical engineering and bioengineering at the university. The device could be the first lens-free microscope that can be used for high-throughput 3-D tissue imaging, an important necessity in the study of disease, according to a news release from the university.

Ozcan’s lab has also been responsible for several custom designed smartphone attachments and apps that can do everything from analyze food samples for allergens, water samples for heavy metals and bacteria, and cell counts in blood samples. Ozcan has also explored the use of Google Glass to process the results of medical diagnostic tests.

The microscope works by using a light-emitting diode to illuminate a tissue or blood sample that has been placed on a slide and inserted into the device. They then used a sensor array on a microchip—the same chip used in digital cameras and smartphone cameras—to capture and record the pattern of shadows created by the sample.

The device will then process these patterns as a series of holograms that form 3-D images of the specimen, providing medical personnel with a virtual depth-of-field view. An algorithm then color codes the reconstructed images, making the contrasts in the samples more apparent that they would be in the holograms, making any subsequent abnormalities easier to detect.

The group began testing the device on pap smears that indicated cervical cancer, tissue specimens containing cancerous breast cells, and blood samples containing sickle cell anemia. A board-certified pathologist analyzed sets of specimen images that had been generated by the lens-free microscope, as well as images generated by conventional microscopes. The pathologist’s diagnoses using the images provided by the lens-free microscope proved accurate 99% of the time.

This isn’t the university’s first rodeo when it comes to microscope innovation. Last year, electrical and bioengineers from UCLA developed a technology that can capture images from a fluorescent microscope and flow cytometer. The device served as an alternative to the traditionally bulky and relatively costly fluorescent microscopes that are typically used in both biomedical research and clinical diagnosis.

It was in that same spirit that researchers at UCLA decided to take a look into the possibility of a lens-free microscope. What they eventually developed was a device that provides a reconstructed image that can be digitally focused at any depth within the object’s field of view (after image capture) without the need of mechanical focus adjustment.

The results have been successful so far, providing images with sufficient image resolution and contrast for clinical evaluation. Ozcan believes that by providing high-resolution images of large-area pathology samples with 3-D digital focus adjustment, this lens-free on-chip microscopy can be useful in resource-limited and point-of-care settings around the world.