A reliable, non-invasive measurement tool for anisotropy in normal skin and scar tissue

Background Anisotropy of the skin varies depending on different locations and pathological conditions. Currently, no reliable non-invasive measurement tool is available for tissue anisotropy. The Reviscometer (R) is an anisotropy measurement tool that measures the resonance running time (RRT) of a shock wave. This study was initiated to establish the reliability of the Reviscometer (R) on normal skin and scars, and to provide basic information on tissue alignment in normal skin and scars. Methods Fifty volunteers and 50 patients underwent measurements on normal skin and scars, respectively. All measurements were performed by the same two observers. Measurements on normal skin were performed on the forearm, upper arm, and abdomen. Results The results showed that the intraclass correlation coefficient of the inter-observer reliability was >= 0.79 on normal skin and >= 0.86 on scars. In normal skin, the highest mean RRT was found on the abdomen (156.4 +/- 48.8), followed by the upper arm (123.2 +/- 33.6) and the forearm (112.5 +/- 24.3). A significantly lower mean RRT was found in scars (52.3 +/- 21.9) compared with normal skin (91.6 +/- 37.7). Conclusion Reviscometer (R) measurements were reliable for normal skin and scars. In addition, clear differences between scars and normal skin but also within different locations on normal skin were identified. The Reviscometer (R) can be considered for the evaluation of the efficacy of different treatments.