Researchers have invented a miniature, soft sensing device to swiftly and precisely diagnose and monitor skin disorders and cancers by evaluating tissue stiffness.
The skin is not only the body’s largest organ but also the primary barrier against foreign aggressors like bacteria, viruses, and UV rays. The skin also helps to regulate many internal functions to sustain our overall wellbeing. Naturally, they are most susceptible to impairment and deterioration, at risk of a wide array of disorders and diseases.
Presently, medical instruments used to diagnose and evaluate the skin, like magnetic resonance elastography, are large and technically demanding, used only by trained practitioners. To overcome those limitations, the latest tissue stiffness-measuring technologies have been adapted for portability and technical ease of use. But these improvements do not come without cost. In exchange, most are limited in its measuring ability, capable of only measuring to a superficial depth of the upper dermal layer – up to micrometre scale. However, a recently developed soft sensing device has come to offer the best of both worlds.
A team of researchers, co-led by Dr Yu Xinge from the University of Hong Kong (CityU), has designed an electromechanical device that can be utilised for the diagnosis of deep tissue pathology. The miniature device not only offers automated and non-invasive detection of skin disorders, but also swift measurements and precise, real-time evaluations of tissue stiffness. The team’s findings are expected to lay the groundwork for innovative diagnostics of skin cancers and dermatological disorders.
The instrument is comprised of a soft, strain-sensing sheet with a vibratory actuator that can be applied on the skin. With a thickness measuring only 2.5mm, the device was proven to be effective for monitoring tensile stiffness of hair-bearing and hairless patches of the skin, up to a depth of 8 mm. The technology was adapted from the principle of a skin-integrated haptic interface for virtual reality, and can quantitatively analyse sensory data of tissue stiffness within 1 minute.
To evaluate the effectiveness of their instrument, its performance was examined using an array of synthetic and biological materials such as hydrogels, pigskin, and human skin. They measured and noted that lesions exhibited higher stiffness in comparison to that of nearby skin, suggesting that these differences are due to variation in skin elasticity and hydration. These measurements are valuable to monitor, diagnose and treat various ailments, specifically skin disorders.
"These simple measurements have potential clinical significance in rapidly identifying and targeting skin lesions, with capabilities that complement those of recently reported methods for sensing mechanical properties at tissue surface (typically micrometre-scale)," Dr Yu elaborated.
Dr Yu also drew attention to the fact that cancer tissues markedly display unusual stiffness or softness as compared to normal tissues. As such, this property can be used as a potential diagnostic biomarker for skin cancers, tumours, or other dermal disorders.
To further investigate its efficacy, the newly invented device was put to the test in clinical studies involving patients with skin disorders. The device demonstrated remarkable accuracy to target lesions linked to psoriasis and evaluate other physical properties of the skin like ageing and loss of hydration, successfully establishing its practicality for medical use.
"The data produced can assist in diagnosis, treatment tracking and disease monitoring particularly for skin associated disorders such as skin cancer, as well as in aspects of aesthetic dermatology and of the recovery from surface wounds," Dr Yu stated. "In the near future, we believe this technology will allow people to monitor their skin health status anytime with a simple wearable device."
Source: Song et al. (2021). Miniaturized electromechanical devices for the characterization of the biomechanics of deep tissue. Nature Biomedical Engineering, 1-13.