Integrated Encryption Model For Medical Image Privacy Protection

With the rapid development of Computed Tomography(CT),magnetic resonance(MR)and other medical imaging technologies,medical imaging devices are widely used in clinical diagnosis and treatment of major diseases such as cancer.Large numbers of image data are used by doctors to help diagnose patients.Digital medical images are of great convenience to electronize the medicine service.However,confronting the uneven distribution of high-quality health resources,how to use expensive imaging equipment in China to achieve effective sharing of regional image data,has become one of the research hotspots of hospital informatization.As the new technologies develop,patient privacy information is at increasing risk.Privacy information in the digital medical images is vulnerable to tampering,theft,damage and other illegal attacks.Because of the sensitivity of medical image data,there is a great need to solve the problem of information sharing.It is a key problem for the academic community to find a scientific and reasonable balance between the development of data value and the protection of personal privacy.In this paper,we research on the image encryption technology based on the digital medical image for privacy protection,including the following three points:(1)On the basis of the existing image encryption algorithms,we aim at improving the security of medical image encryption,as well as the encryption and decryption speed of the large size image.In view of the spatial and temporal characteristics of the coupled map lattice model,combining 2D images into the model to achieve more chaos and more security.On the premise of ensuring security,a fast image encryption algorithm based on bit plane is proposed,which takes advantages of the sensitivity to initial values of chaos theory.(2)According to the content feature of medical images,some specific regions are more important than other regions.We design the medical image encryption algorithm based on region of interest(ROI).The medical image is divided into ROI and region of non-interest(RNOI)at first,and then different Scan encryption methods are applied in different regions.The key contains the corresponding hash function value,which confirms the integrity of the medical image simultaneously.(3)To fulfill privacy anonymous protection of Digital Imaging and Communications in Medicine(DICOM)medical data in the existing personal electronic health records system,a patient-centered privacy protection scheme combining the above improved medical image encryption algorithms is proposed.Considering the different requriements of application users,we extend the service function of original Electrical Medical Records(EMR)by different encryption processes of hierarchical privacy protection,to meet the need of hospital using EMR as an aided diagnosis and treatment as well as realize patients' personal requirements on efficient privacy protection of the image data in E-health.