Dermal striae (DS) or stretch marks are a dermatological condition seen microscopically as the separation of collagen fibers and rupture of elastic fibers, which are curled and clumped at the edge of the lesion. 1 In this condition, fibrillin and elastin appear in reduced amounts and are reorganized in the deep dermis. The result is discontinuity of the dermal tissue and reduction in the thickness of the epidermis and papillary dermis. 1,2 Dermal striae are in the second layer of skin, the dermis. 1,3 It can occur in small or large quantities, elevated or depressed in aspect, and vary in shape and size. DS lesions tend to appear in a parallel formation and perpendicular to the skin tension lines (STL) 4,5 which are lines that determine the maximum tension direction of human skin. 6
Background The tendon is a structure found in different parts of the human body. Damages within tendons cause movement deficit and discomfort, which requires medical and therapeutic treatment. One useful tool is the therapeutic ultrasound; however, fine adjustment is required to avoid further lesions to the patient. Aiming at enhancing the resources for the research in the study of therapeutic ultrasound and the knowledge regarding its application to tendons, the objective of this work is to evaluate materials to prepare ultrasonic phantoms that mimic the acoustic properties of the tendons. Materials and methods The acoustic characterization of a pig tendon and three PVCP-based phantoms were made. The transmission-reception method was used, and the propagation speed and attenuation of each phantom were calculated. Results The tendon showed an attenuation of 4.8 ± 1.7 dB cm −1 and propagation speed of 1497.5 ± 21.6 m s −1. The attenuation of the phantoms varied from 1.3 ± 1.2 to 4.0 ± 1.0 dB cm −1 and velocity from 1509.9 ± 31.8 to 1519.8 ± 26.7 m s −1. Conclusions We concluded that among the materials used, it was possible to find values statistically similar to this animal tendon in the PVCP phantom with 15% glycerin and 10% PVC powder. Complementary studies with other materials and protocols are needed to mimic other values found in the literature.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.