When a person has a skin problem, the affected skin is usually harder or softer than normal, according to foreign media reports. Now, a new sensor has been shown to detect these differences, and it may allow doctors to diagnose the problem more quickly and easily. The electromechanical device is said to have been designed by a collaboration between scientists at City University of Hong Kong in China and Northwestern University in Illinois.

It is actually modified from a tool previously developed by the latter, which was used to provide haptic feedback to users of virtual reality (VR) systems. The hard-wired sensor, which is only 2.5 millimeters thick and has a contact area of only 2 square centimeters, is simply placed on the skin of a person suspected of having a problem. Alternating current is applied to the device through a coil thus causing the integrated magnet to vibrate rapidly.

As the magnet vibrates, it sends pressure waves up to 8 mm deep into the skin. Although the degree of deformation of the skin depends on its tensile stiffness, it will rapidly deform in response to these waves. A strain sensor at the bottom of the sensor measures these skin deformations and transmits them to a connected computer, which converts the data into a skin stiffness value. This value can then be compared to those associated with specific skin diseases.

Although there are already diagnostic systems that measure skin tensile stiffness, they are large devices that must be operated by trained technicians and they can only "read" the outermost layer of the skin. In contrast, this inexpensive new sensor can be used in a doctor's office and even allows people to monitor their own skin health in their own homes, provided, of course, that it can be commercialized. The device is currently the subject of clinical studies in which it is being used to detect hairy and hairless skin in patients with skin problems. In addition, it has been found to reliably detect psoriasis in just one minute. It is believed that once this technology is further developed, then it should be equally capable of detecting other conditions.