In medical field, a large number of diverse radiological and pathological images in digital format are generated everyday in hospitals and medical centers with the help of sophisticated image acquisition devices and digital scanners. Medical images are generally complex in nature and are used for diagnosis, therapy, research and education. A fundamental role of radiologists in clinical medicine is to provide physicians or specialists reports containing timely patient information obtained from image interpretation, together with appropriate recommendations for subsequent radiological investigations. Support of patient prior image references is critical to a radiologist's examination reading, providing a baseline essential for confirmation, comparison and/or evaluation of the suspicious radiographic signs detected on the current examination images. Such support is of clinical importance and may have significant effects on radiologists examination reading efficiency, work satisfaction and service quality.