Title
Towards quantitative assessment of calciphylaxis
Abstract
Calciphylaxis is a rare disease that has devastating conditions associated with high morbidity and mortality. Calciphylaxis is characterized by systemic medial calcification of the arteries yielding necrotic skin ulcerations. In this paper, we aim at supporting the installation of multi-center registries for calciphylaxis, which includes a photographic documentation of skin necrosis. However, photographs acquired in different centers under different conditions using different equipment and photographers cannot be compared quantitatively. For normalization, we use a simple color pad that is placed into the field of view, segmented from the image, and its color fields are analyzed. In total, 24 colors are printed on that scale. A least-squares approach is used to determine the affine color transform. Furthermore, the card allows scale normalization. We provide a case study for qualitative assessment. In addition, the method is evaluated quantitatively using 10 images of two sets of different captures of the same necrosis. The variability of quantitative measurements based on free hand photography is assessed regarding geometric and color distortions before and after our simple calibration procedure. Using automated image processing, the standard deviation of measurements is significantly reduced. The coefficients of variations yield 5-20% and 2-10% for geometry and color, respectively. Hence, quantitative assessment of calciphylaxis becomes practicable and will impact a better understanding of this rare but fatal disease.
Year
DOI
Venue
2014
10.1117/12.2043820
Proceedings of SPIE
Keywords
Field
DocType
Calciphylaxis,Photography,Skin necrosis,Geometric registration,Color calibration,Quantitative measurements,Wound management,Scale invariant feature transform (SIFT)
Field of view,Affine transformation,Computer vision,Normalization (statistics),Color calibration,Optics,Image processing,Photography,Artificial intelligence,Standard deviation,Calciphylaxis,Physics
Conference
Volume
ISSN
Citations 
9035
0277-786X
1
PageRank 
References 
Authors
0.37
1
7
Name
Order
Citations
PageRank
Thomas M Deserno135833.79
istvan sarandi262.47
abin jose312.40
Daniel Haak4406.52
Stephan Jonas5358.92
paula specht610.37
Vincent Brandenburg731.44