Allergic reactions are very common in developed countries, particularly among children and young people. Today it is considered the epidemic of the XXI century. In addition, both direct and indirect costs have increased due to medicines and casualties from allergic attacks. In the 1960s, the percentage of the population allergic to pollen ranged from 0.5% to 2% in Europe, the United States and Japan; nowadays it has risen to 30%. It is estimated that more than 10% of the European population suffers a chronic allergy, and that 30% will suffer an allergic episode at some point in their life (either food, skin or respiratory).
There are different methods to diagnose the possible allergies that a given patient can suffer, among them the most widespread is the Prick Test. The Prick Test consists in the deposit of a drop of the allergen that is wanted to test on the patient's forearm and then pierce it with a punch that breaks the skin, getting the allergen to enter the system. After 5 minutes, the patient will show a reaction in the form of redness in the same area where the test was performed. Between 10 and 15 minutes later, a protrusion will be formed and will extend according to the severity of the allergic reaction. This protuberance is called "papule" (or “wheal”).
The papules are used as the method to quantify the sensitivity of a patient to an allergenic substance. In order to compare the different reactions that patients can present, these papules are parameterized, resulting in the maximum diameter of the papule, the mean diameter or its area. In this way, it is possible to compare an allergic reaction with another, either between the same patient on different days and between different patients.
However, it should be emphasized that in the current context of allergy, the variables of diameter or area taken represent a qualitative value rather than a quantitative value due to the lack of precision in the measurement of these papules. This is why in recent years the scientific community has focused its efforts on improving the reading of allergic reactions, either improving the Prick Test process, or completely changing the test methodology.
The current reading process is very poor considering the technology available in today's hospitals. In the 21st century, allergic reactions are still measured by contouring them with a marker and comparing them to each other in terms of size. The major advances in the comparison of allergic reactions include obtaining the maximum diameter of the papule, calculating the mean diameter or obtaining the area. For this, the allergist uses such rudimentary techniques as measuring by means of a ruler on the patient to obtain the diameter, or transfer the contour by means of an adhesive tape to a millimeter sheet to be able to count squares and estimate the area. It is evident the lack of precision in the current methodology of the Prick Test, being able to only obtain qualitative parameters besides being open to human errors.
INNOPRICK, is the result of a doctoral thesis, developed in 2012-2015 at Tecnun (University of Navarra-Spain). The results arisen from the thesis, was the creation of a new spin off company (InnoPrick), highly specialized, for the final developments, fabrication and commercialization of a medical device to identify and quantify papules.
The InnoPrick solution consists of a device capable of scanning the patient’s forearm, after implementing the different allergens into the skin and once the papules have appeared, and through a processing software identify and parameterize the papules originated by the reaction to allergens.
The technology developed and tested uses a laser beam which projects on the surface and reflects on a two-dimensional CCD sensor, and by means of triangulation the distance of said line (each of the points that compose it) is obtained to the device; by repeating this process several times it obtains a three-dimensional surface of the scanned object. See the following picture and screen shot:
This innovative technology was incorporated into a novel device that offer a new reading methodology much quicker and easier to use while giving the process a greater precision (+40%), and therefore greater objectivity and reliability, time reduction (40%), which directly involves costs reduction and the process digitalization which the current manual process does not have.
