Processed skin surface images acquired by acoustic impedance difference imaging using the ultrasonic interference method: a pilot study

Abstract

To clarify the potential of a novel system using the acoustic impedance difference imaging (AIDI) method for diagnosis of skin disorders, we used it on a coin and swine skin. An ultrasound wave with a central frequency of 20 MHz, emitted from a fused quartz rod with a diameter of 1.25 mm, was focused on the surface of the coin and skin samples. The difference in acoustic impedance was determined by the reflection-type interference-based acoustic impedance measurement method. The processed data were produced as greyscale images on which the maximum measured amplitudes were mapped. We applied the method to a coin. Swine skin, burned and covered with an acrylic sheet with a thickness of 0.2 mm (a few times the half-wavelength) to eliminate the undulations of the skin surface, was employed to obtain processed images from which undulation data were excluded. All the processed images obtained corresponded almost exactly with the magnified optical ones. In the processed images of swine skin, a marked difference was found after the burning procedure. The processed images obtained using the AIDI method reflected not only the undulations but also other information such as elasticity. In conclusion, our system using AIDI has the potential to become a useful modality for the diagnosis of skin disorders.

A deep learning model for burn depth classification using ultrasound imaging

“…The speckles are the manifestation of microstructural degradation of thermally damaged skin tissue. Thermal damage induces contrasting acoustic impedance in the burned skin tissues (Fujii et al, 2012). The strong scattering signals from the burn site with contrasting acoustic impedance produce intricate interference patterns that appear as speckles in the ultrasound images.…”

“…Unlike optical imaging modalities, ultrasonography can detect alterations in tissue acoustic impedance and therefore provides richer information regarding the penetration depth of a burn. Thermal treatment is known to alter the acoustic impedance of tissues (Fujii et al, 2012). The change in acoustic impedance is related to modifications in skin tissue morphology due to microdetachment of the epidermis from the dermis and vacuolar cytoplasmic disintegration in the basal cell layer in case of partial-thickness burns, and denaturation of collagen and sometimes infiltration of the dermis by exudative cells in case of full-thickness burns (Moritz, 1947).…”

Real-time Burn Classification using Ultrasound Imaging

“…The score on the y-axis is defined by Supplementary equation (S3.5) and the sign of the designated data determines the burn group to which the data belongs. www.nature.com/scientificreports www.nature.com/scientificreports/ change the acoustic impedance of tissue 53 . The speckles in the ultrasound images appear due to the interference of strong scattering signals from the regions of contrast acoustic impedance acting as "ultrasound contrast agents" (UCAs); thereby greatly improving the contrast-to-tissue ratio (CTR) of the ultrasound images.…”