A new high-resolution method for imaging below the skin using a liquid lens

University of Rochester optics professor Jannick Rolland has developed an optical technology that provides unprecedented images under the skin’s surface.

The aim of the technology is to detect and examine skin lesions to determine whether they are benign or cancerous without having to cut the suspected tumor out of the skin and analyze it in the lab. Instead, the tip of a roughly one-foot-long cylindrical probe is placed in contact with the tissue, and within seconds a clear, high-resolution, 3D image of what lies below the surface emerges.

Rolland presented her findings at the 2011 annual meeting of the American Association for the Advancement of Science in Washington, D.C., on Feb. 19.

“My hope is that, in the future, this technology could remove significant inconvenience and expense from the process of skin lesion diagnosis,” Rolland says. “When a patient walks into a clinic with a suspicious mole, for instance, they wouldn’t have to have it necessarily surgically cut out of their skin or be forced to have a costly and time-consuming MRI done. Instead, a relatively small, portable device could take an image that will assist in the classification of the lesion right in the doctor’s office.”

The device accomplishes this using a unique liquid lens setup developed by Rolland and her team for a process known as Optical Coherence Microscopy. In a liquid lens, a droplet of water takes the place of the glass in a standard lens. As the electrical field around the water droplet changes, the droplet changes its shape and therefore changes the focus of the lens. This allows the device to take thousands of pictures focused at different depths below the skin’s surface. Combining these images creates a fully in-focus image of all of the tissue up to 1 millimeter deep in human skin, which includes important skin tissue structures. Because the device uses near infrared light instead of ultrasounds, the images have a precise, micron-scale resolution instead of a millimeter-scale resolution.

The process has been successfully tested in in-vivo human skin and several papers on it have been published in peer-reviewed journals. Rolland says that the next step is to start using it in a clinical research environment so its ability to discriminate between different types of lesions may be assessed.

Portable laser devices to improve disease diagnosis

Portable devices that use a laser beam to probe bones, teeth, and other parts of the body for early signs of diseases like osteoporosis and tooth decay may seem like something out of science fiction. But those devices are moving closer to reality, according to Chemical & Engineering News (C&EN).

These new diagnostic tools will have the ability to see beneath the skin and detect disease, without exposing patients to X-rays. They embrace a technology that involves focusing a laser beam painlessly through the skin onto a bone or onto the surface of a tooth. After hitting its target, the beam returns to an electronic detector with imprinted information that can reveal whether disease is present. Called Raman spectroscopy, the technology is a mainstay tool in chemistry laboratories that is finding a new life in medicine.

The article describes growing medical interest in Raman-based devices, especially for diagnosing osteoporosis and other bone diseases, and for tracking the effectiveness of treatment. Another application may be in very early detection of tooth decay, so that dentists can treat soft spots on tooth enamel before “drill-and-fill” becomes the only option. The technique could also mean blood tests done without taking blood samples, the article indicates.