Use of high frequency ultrasound to detect changes in skin integrity: An image evaluation validation procedure

Abstract

High frequency ultrasound (HFUS) scanning may be used for prevention, detection and monitoring of pressure ulcers in patients at risk and is amenable for portable, bedside use by a variety of clinicians. Limited data are available about the criteria to determine an ideal image or measures of tissue changes representative of tissue injury. We developed and evaluated criteria for overall image quality and measures of tissue integrity. In 40 mechanically ventilated adults in 3 ICUs, 241 HFUS sacral images were evaluated for agreement using criteria for overall image quality and tissue changes (dermal, hypodermal layer thickness and layer density). HFUS sacral images (N=241) were evaluated in three analyses and showed poor agreement in all three analyses using the specific criteria for global quality, however when criteria were collapsed agreement was good to substantial. Evaluator agreement for layer thickness and layer density was also good. A global rating is adequate for identifying good images. Agreement for measurements of layer thickness and density were also good and may be useful to identify early changes in tissue integrity leading to tissue injury. Additional data are needed concerning the association of changes in layer thickness and layer density to eventual tissue injury.