Medical images, security and watermarking

In this article, security issues for medical information and technical solutions to protect these data in Medical Information Systems are examined. We then introduce the watermarking as a complementary security tool. The relevance of this new technology in healthcare is discussed from the application viewpoints and through the implementation constraints. A solution is proposed, based on an original approach which consists in watermarking image areas that are not relevant for the diagnosis. This system is transparent to the user and allows image integrity control. In addition, it provides information on the location of potential alterations and an evaluation of image modifications which is of major importance in a medico-legal framework. An example using head Magnetic Resonance Imaging illustrates the overall method.