COMPARISION OF DIFFERENT IMAGING TECHNIQUES USED FOR CHRONIC WOUNDS

Abstract

Many people suffer from chronic wounds .It is a maj or problem in healthcare .worldwide. The treatments of chronic wounds include monitoring colour and size (area or volume) of the wound at regular intervals. This evaluation is ofte n based on qualitative observation and manual measurements of the wound. Now a days there several researchers are developing technologies to assess the clinical improvement of chronic wounds. This paper aims to provide a study on imaging technologies app lied to chronic wounds. A study on imaging technolo gies applied to chronic wounds is presented. Their reliability, precision, and usage are compared. The methods are divided int o three categories: planimetric techniques, volumetric Technique and ti ssue classification. In this paper, a study on imaging technologies appl ied to chronic wounds is presented. Their reliability, pre cision, and usage are compared. The most common methods used by the clinicians are discussed here. They are mainly base d on manual approaches for estimation of the area of the wound and, therefore, they suffer from high inaccuracy. T hese methods may be divided into techniques that measure area and perimeter, and techniques that measure volumetric information. The first method uses a ruler (or a c aliper) to measure the major and minor axes of the lesion. Bas ed on these two measurements, the area of the wound is es timated as a rectangle or as an ellipse. When the model is a rectangle, the area may be overestimated by 10% to 45% with less accuracy for smaller wounds .When the model is a n ellipse, it was reported an error between 16% and 40% of the real area . In either model, the decision of the major a xes is subjective and has an impact on the variability of the method. In second approach a transparent film is placed ove r the wound and tracing the outline with a permanent marker. Afterwards, the film is placed on a metric grid and the area is calculated by counting the number of squared millim etres contained within the outline. This process is prone to human error. Several studies have shown that the most im portant factor in error measurement is the correct and con sistent identification of the border of the wound due its poor definition or the subjectivity of the process . Also, the number of partial squares of the grid inside t he outline and the thickness of the marker may cause some inaccuracy. All the described techniques require direct contact with the wound to measure or estimate its area. Some other t echniques have been evaluated to estimate the volume of the w ound by