Computer-aided skin prick test

The interpretation of the skin prick test is subject to inter-observer variation. To remove this variation, a computerized procedure for the skin prick test is suggested. Instead of manually measuring the emerging wheals, a series of photographs is automatically taken of the forearm. The photographs thus taken are then analyzed with a digital image processing algorithm to give the measurement results. The computerized test has the added benefit of being able to produce a time series for the wheal size. This makes it possible to see the onset time of the reaction in addition to the size of the wheal. Preliminary feasibility test suggests that the simple setup described in this letter is able to perform the skin prick test automatically and to show the kinetic behaviour of the wheal. The main challenges with the test setup are related to illumination and wheal detection algorithms.