A Comparison of Three Methods for the Analysis of Skin Flap Viability: Reliability and Validity

Abstract

Technological advances have provided new alternatives to the analysis of skin flap viability in animal models; however, the interrater validity and reliability of these techniques have yet to be analyzed. The present study aimed to evaluate the interrater validity and reliability of three different methods: weight of paper template (WPT), paper template area (PTA), and photographic analysis. Sixteen male Wistar rats had their cranially based dorsal skin flap elevated. On the seventh postoperative day, the viable tissue area and the necrotic area of the skin flap were recorded using the paper template method and photo image. The evaluation of the percentage of viable tissue was performed using three methods, simultaneously and independently by two raters. The analysis of interrater reliability and viability was performed using the intraclass correlation coefficient and Bland Altman Plot Analysis was used to visualize the presence or absence of systematic bias in the evaluations of data validity. The results showed that interrater reliability for WPT, measurement of PTA, and photographic analysis were 0.995, 0.990, and 0.982, respectively. For data validity, a correlation >0.90 was observed for all comparisons made between the three methods. In addition, Bland Altman Plot Analysis showed agreement between the comparisons of the methods and the presence of systematic bias was not observed. Digital methods are an excellent choice for assessing skin flap viability; moreover, they make data use and storage easier. Independently from the method used, the interrater reliability and validity proved to be excellent for the analysis of skin flaps' viability.

Subcutaneous Vulvar Flap Viability Evaluation With Near-Infrared Probe and Indocyanine Green for Vulvar Cancer Reconstructive Surgery: A Feasible Technique

“…Unlike angiography which shows an objective assessment of the degree of flap vascularization, with our method, the evaluation should be limited to the uptake vs. non-uptake. However, in line with our method and as reported by several authors, a standardized method for vulvar flap viability evaluation is still absent, and subjective clinical evaluation still represents one of the best methods for assessing vulvar flap vitality (30)(31)(32). Furthermore, it would be useful to prospectively evaluate the flap viability using ICG and infrared probes with only clinical evaluation to assess whether this new method allows better surgical outcomes.…”

The effects of optimizing blood inflow in the pedicle on perforator flap survival: A pilot study in a rat model

“…The images were then processed with Adobe Photoshop (Adobe, San Jose, CA, USA). After the images were converted to BMP format, the pixel counts of the viable flap area (with relation to gray levels) and of the total flap area were counted, as has been described in the literature 13 . The flap viability area was then calculated using the following formula: …”