Microscopic probe creates images beneath tissue surface

A new microscopic diagnostic probe is capable of viewing beneath the surface of tissues to build up 3D depth image.

The probe could be used by doctors to diagnose oral cancer in real-time or as a surgical guidance tool. Dentists could also use it to screen for early-stage cancer cells.

It uses a laser to illuminate areas of the sample and can view beneath the surface of tissue, creating full 3D images. It can also take a series of images and layer them on top of each other, much like the tiling of a mosaic, giving a large overall field-of-view.

The key component of the probe is a micromirror. These have previously been used in barcode scanners and fibre optic switches and are controlled by a microelectromechanical system, allowing the laser beam to scan an area in a programmed fashion.

Micromirrors are relatively low cost and easy to fabrication as well as being able to integrate into electronic systems.

Oral cancers have traditionally been diagnosed by biopsy. Based on a doctor’s visual inspection, medical practitioners remove a sample of tissue from the patient and send it off to a pathologist who will examine the tissue under a microscope to check for abnormal or malignant cells.

Results will be sent back to the doctor for the next round of diagnoses or surgery; the whole process can take up to several weeks. Not only is this process time consuming, it can be costly, invasive and painful, often leaving scars

‘Due to the lack of real-time efficient oral cancer screening tools, it is estimated that approximately $3.2 billion is spent in the United States each year on treatment of such cancers,’ said Dr John Zhang at the University of Texas at Austin.

The researchers, and commercial partner NanoLite Systems, Inc. are now planning clinical trials with a view to gaining approval from the Food and Drug Administration (FDA).

They envisage that, with adjustments, the device could be built for a quarter of the price it costs to build the microscopes that are currently used in diagnosis, which is around $300,000.