The skin thickness and stiffness at the rear wrists and cheeks were evaluated in 7 subjects (1 male and 6 women,
age 28-55 years) on both sides.
Real-time 2D-SWE of the skin performed by US machine Soneus P7 (Ultrasign,
Ukraine) with conventional broadband linear 5-12 MHz probe .
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The unique property of equipment is the absence of the elastography "dead zone" in the dermis under the contact surface of the probe aperture.
All subjects underwent three procedures of the skin RD by Hyalual booster intradermally injection with an interval of 2 weeks [9].
Real-time 2D-SWE performed before and two weeks after the last injection.
First,
we performed real-time B-mode of the echostructure of the skin and subcutaneous fatty tissue,
as well as underlying tissues (fascia,
muscles,
bones,
tendons,
etc.).
The thickness of the dermis was measured at 3 points along the sensor aperture of 38 mm and the average value was calculated.
The choice of the SV 2D-SWE position and diameter was determined in accordance with the thickness of the dermis in B-mode .
In order to eliminate the precompression artifact of the dermis by the probe,
we applied the principle of a “gel pillow”.Standardization of the gel layer thickness of the 1-2 mm and prevention of precompression was achieved by using the original nozzle rubber band.
Fig.1.
It is also known that the skin mechanically exhibits anisotropic properties and its ability to stretch and shrink in different directions varies significantly [4,
15].
In order to avoid the influence of anisotropy of the orientation connective tissue fibers of the skin on the results of elastometry,
we located the US prober in the same standard direction.
On the rear wrists the probe was oriented along the long axis of the bones above the interosseous gaps.
On the cheeks the probe was standardly oriented in a direction parallel to the edge of the mandibula.
The quality control of elasto-visualization and elastometry was always carried out in real time by the standard deviation (SD) value and the mapping of errors of the 2D-SWE in the ROI on a pink-green scale (δ,%).
Fig.2.
Statistical data processing of the research results was carried out using IBM SPSS Statistics Base v.22.
The statistical significance of the data was set at p <0.05.
Results are presented in M ± SD.