Registration and Fusion Techniques for Medical Images: Demonstration and Evaluation

In this work, we present an integrated system for the registration and fusion of medical images, named << dIaGnosis >>. It is often necessary to align medical images to illustrate the changes between the data retrieved at different times so as to assess the progress of a disease, or to assess the effectiveness of a treatment. The proposed system supports the storage, retrieval, distribution and presentation of medical images from different modalities, such as CT and MRI, in DICOM format. It also supports multiple examinations per patient and uses parallel processing threads to perform the processing of the acquired three-dimensional (3D) images in almost real time. In this paper, the architecture and the working environment of the implemented system are presented in detail, along with a pilot scenario that demonstrates the system in use. Additionally, the registration and fusion algorithms implemented are presented and evaluated, along with the image processing techniques used for the enhancement of medical images. The contribution of the proposed work is multilayered. It provides automatic matching methods based on both segmented surfaces and on different levels of gray, and it improves the alignment process when there is a relative movement and / or distortion of images in the data collected from different imaging systems.