High Resolution Portable Probe for Skin Biopsies
A compact probe developed in several university labs combines laser technologies for rapid biopsies of skin cancer in hard-to-reach places.
Jointly developed with Vanderbilt University.
The incidence of skin cancer continues to grow worldwide. A person has a 4% chance of developing the most aggressive form of skin cancer, melanoma, which is the more deadly type. Early detection is critical to improved survival. Melanoma develops quickly and spreads, can appear on skin that is not normally exposed to sunlight, and can become life-threatening in as little as six weeks. Considerable R&D effort has gone into developing non-invasive, rapid tissue scanning using optical techniques that can be done in the clinic at lower cost. Two of those techniques are scanning confocal microscopy (CM) and confocal Raman spectroscopy (CRS), both powerful tools for tissue biopsies. Scanning confocal microscopy is capable of subsurface imaging in real-time, however the images do not identify composition. Confocal Raman spectroscopy, on the other hand, can provide detailed biochemical analyses of tissue. However, these instruments are typically contained in large bench-top microscopes and devices that are restricted to a laboratory setting. Furthermore, imaging formation can be slow.
Vanderbilt University and Montana State University have patented a probe that combines and miniaturizes these confocal technologies into a dual-modal scanner with the effective power of a large microscope. Tethered to a benchtop assembly, this small and mobile probe allows for simultaneous spectroscopy and imaging while sweeping across hard-to-reach places. Additionally, it can scan over varied topography on the scale of a few cells (≈20 μm). Questionable skin lesions could be diagnosed without the need for removal and biopsy.
A protype probe consisting of a micro-electromechanical system (MEMS) of mirrors was built into a probe with dimensions of 18 cm (L) x 11 cm (W) x 6 cm (H) connected to a control box that provides laser output and control. The two-dimensional MEMS scan mirror simplifies the design of the confocal microscope compared to the x-y pair of galvanometer scan mirrors that are typically used in a scanning microscope. The use of the MEMS scanner allows the probe to be small enough to easily hold by hand and scan over the skin and image at 56 frames/sec. The probe integrates confocal reflectance imaging, confocal Raman spectroscopy, and gross spatial imaging to evaluate the tissue at micron-scale resolutions. A camera in the probe captures images of the lesion, enabling registration between the microscope image and the biochemical structure and real-time histology of the tissue. Further miniaturization could potentially enable the development of a probe capable of conducting oral tissue biopsies.
Rapid, less expensive skin biopsies and images conducted in a clinical setting
Ability to scan hard-to-reach places
Ability to scan a variety of skin topographies
Spectral measurements at various depths
Easy to train
Intellectual Property Status:
Nick Zelver, MSU