Purpose: The outcome of treatments in plastic surgery is often best evaluated by visual images. For example, evaluation of burn wounds remains primarily a clinical determination dependent upon visual inspection of the wound. In attempt to use this clinical information in a web-based, blinded, prospective, multicenter trial, we developed a technique to use standardized digital photography to evaluate burn depth clinically and area by digital planimetry. This technique could be adapted for other visually oriented studies.
Material and Methods: Each center randomizes the patient care per protocol and the principal investigator is readily "blinded" to the method of treatment. Photos in each center are taken with identical Nikon Coolpix 995 digital cameras. Standard settings for flash, white balance and zoom are set with instructions on our website for each center to reference. Photos are obtained as high resolution (9 MB) images with a specially designed background that contains a gray scale, white scale, black scale and centimeter scale. Distance to the subject is kept consistent by including a consistent portion of the standard background. After obtaining the images they are directly downloaded via the website and stored on servers at the principal investigator's home institution. Color adjustments to each photo are made using Adobe Photoshop 6.0 to correct for errors due to differences in ambient light. Images are then evaluated on a 21inch Trinitron monitor calibrated with OptiCAL 3.5. Using SigmaScan Pro 5.0 (SPSS Science) the areas of the wounds are determined by digital planimetry. In this manner, wounds can be evaluated in a longitudinal fashion to evaluate the rate of healing and clinically estimate burn depth.
Results: This technique has been used to evaluate the initial 20 patients in a national study involving seven centers. As a web-based study the principal investigator is able to monitor each patient in the study within 24 hours after the patient is enrolled to insure consistency. Images obtained even by individuals denying experience in photography have been reliable and useful for clinical evaluation and quantifying wound area.
Conclusions: This method of standardized digital photography allows for clinical evaluation and quantification of wound size in a consistent manner in a web-based multicenter trial of burn care. This technique could readily facilitate future prospective multicenter studies that are primarily measured by visual images such as wound treatments and cosmetic surgery.