Computerized Wound Image Analysis

Summary

The concept is based on assessing macromorphological changes in wounds during the healing process. These changes are expressed in terms of colour characteristics and the area of the necrotic tissue and total wound. The colour shifts for the phases between black/yellow (necroses/fibrin) and the red tissue (granulation) are quantified. The wound is reproduced on Polaroid colour film by a special camera (Acmel) equipped with a ring strobe and a focusing aid, that renders sharp and well centered close-up photographs without need for a view finder or touching the wound. Reflections are minimized by tilting the camera at an angle of 30° to the normal wound surface plane. To make it possible to later correct for colour and optical/geometrical distortion in the photograph, a reference scale is incorporated alongside the wound. The photographs taken daily throughout the treatment period are collected and digitally processed via a video camera. The information obtained is then fed into an image processing system (Epsilon, Imtec AB, Uppsala). The colour of every single pixel in the wound image is automatically determined according to the standardized classification table and shown in tabular form. The method allows rapid and objective analysis of large series of wound images which considerably facilitates the evaluation of wound healing and markedly increases the reproducibility of result assessment.