Beyond flat weals: validation of a three-dimensional imaging technology that will improve skin allergy research

Skin-prick tests (SPTs) are a standard way to test for sensitizations to allergens, but to date, techniques that allow for high-quality measurements of the resulting weals for research purposes are lacking. In this study, we assessed a new three-dimensional (3D) imaging technology for its accuracy and consistency. We found that this new technology showed very little intraoperator and interoperator variation for repeated measurements of a model of known area by each of two operators. We also found that repeated measurements of the same object over 4 months showed virtually no variation. Finally, 3D imaging was superior to traditional ruler measurements for assessing SPT reactions to histamine and allergen. For high-quality measurements of SPT reactions, 3D imaging is accurate, consistent and reliable.