Hydroxyurea-Induced Leg Ulcers Treated With a Protease-Modulating Matrix

Methods We prospectively examined 15 patients with venous leg ulcers. The patients who underwent sequential imaging of chronic wounds for this study all attended the leg ulcer clinic of the Wound Healing Research Unit at the University of Pisa, Pisa, Italy. Our sequential imaging system is equipped with a Vivid 900 laser scanner (Minolta, Osaka, Japan), which is used for digitizing or scanning the wound shape. With regard to the calculation of the "external" surface and volume of a wound, it is necessary to assess its original shape to determine the missing volume virtually. At the time of patient presentation, information on the shape of the skin before the wound occurred is missing, and the technique for virtual reconstruction of the original wound surface must be as easy and user-friendly as possible. The system, relying on an analysis of the shape of the surface immediately outside the wound perimeter, creates an interpolating virtual surface that is continuously connected to the existing surface outside the wound and to that covering it. The parameters we studied were the mean wound area (measured in square centimeters) and mean volume (cubic centimeters). To assess interrater reproducibility, scans were evaluated by 2 independent investigators. For assessment of intrarater reproducibility, a single investigator performed 2 consecutive measurements 5 minutes apart. Immediately after the first wound assessment of the first observer, a second observer, blinded to the findings of the first analysis, measured the same wound. The means and standard deviations of duplicate determinations for each wound were used for analysis. The reproducibility of measurements was evaluated by means of an intraclass correlation coefficient (ICC) and its 95% confidence interval (CI). Results The measured total areas and volumes for independent raters and for subsequent measures of 1 rater are reported in Table 1. No statistically significant differences were found between scans evaluated by the 2 investigators about wound area and volume. The relative errors and the intraclass correlation coefficients are reported in Table 2. The ICC values were excellent for both intrarater and interrater reproducibility with a very low relative error value. The mean ± SD time for a full scan acquisition on the wound area and volume was 3.6 ± 1.4 minutes.