Keywords

wound assessment, measuring wound perfusion and tissue perfusion, assessment of underlying tissue

 

Authors

  1. Langemo, Diane PhD, RN, FAAN
  2. Spahn, James G. MD, FACS

ABSTRACT

OBJECTIVE: The timely and accurate assessment of skin and underlying tissue is crucial for making informed decisions relating to wound development and existing wounds. The study objective was to determine within- and between-reader agreement of Scout Visual-to-Thermal Overlay (WoundVision LLC, Indianapolis, Indiana) placement (moving the wound edge trace from the visual image onto the wound edge signature of the infrared image).

 

MATERIALS AND METHODS: For establishing within- and between-reader agreement of the Scout Visual-to-Thermal Overlay feature, 5 different readers overlaid a wound edge trace from the visual image and placed it onto the congruent thermal representation of the wound on a thermal image 3 independent times. Forty different wound image pairs were evaluated by each reader. All readers were trained by the same trainer on the operation of the Scout prior to using the software features. The Scout Visual-to-Thermal Overlay feature allows clinicians to use an anatomical measurement of the wound on the visual image (area and perimeter) to extract a congruent physiological measurement of the wound on the thermal image (thermal intensity variation data) by taking the wound edge trace from the visual image and overlaying it onto the corresponding thermal signature of the same wound edge.

 

RESULTS: The results are very similar both within- and between-readers. The coefficient of variation (CV) for the mean PV both within- and between-readers averages less than 1%, 0.89 and 0.77 respectively. When converted into degrees Celsius across all 5 readers and all 3 wound replicates, the average temperature differential is 0.28[degrees] C (Table 2). The largest difference observed was 0.63[degrees] C and the smallest difference observed was 0.04[degrees] C.

 

CONCLUSIONS: The Scout software's Visual-to-Thermal Overlay procedure, as implemented in this study, is very precise. This study demonstrates that the thermal signature of wounds may be delineated repeatedly by the same operator and reproducibly by different operators. Thus, clinicians can integrate a criterion standard visual (anatomical) assessment with a congruent physiological assessment to provide them with knowledge relating to the presence or absence of blood flow, perfusion, and metabolic activity in the wound, periwound, and wound site.