Methods of measuring wound size: a comparative study.

The lack of an accepted method of accurate and objective measurement of wound dimensions is a major obstacle to the assessment of effective wound management regimes. This study compares three different wound volume measurement techniques (filling the lesion with saline, molding of a dental impression material and a computer vision method based on image processing and the Structured Light technique) in terms of accuracy, precision and practicability in a clinical environment. Three groups of hospital staff, doctors, nurses and technicians, repeatedly measured a set of 6 different models of wounds. Measuring wound volume by filling it with saline produces results with standard deviations between 9 percent and 18 percent of the actual volume. Dental impression material performs better, between 5 percent and 16 percent, but is difficult to apply and time consuming to use. Apart from the advantage of providing instant optical records of wounds, the image processing method produces more reliable volume measurements with a standard deviation of between 3 percent and 15 percent. The results demonstrate that the computer based method yields the most reproducible results with a minimum of inter-observer error but the method is not applicable for undermined, very deep and very large wounds.