Abstract: Colorization is a term used to describe a computerized process for adding color to black and white pictures, movies or TV programs. This process can also be used to convert the gray scale medical images to their colorized version, as color increases the visual appeal of an image and it also makes medical visualization more attractive. In the medical field, there used plenty of images especially X-Rays like dental, chest, leg, hand X-Rays and MRI Images. In this paper, we apply colorization based on optimization to colorize medical images and also evaluate its performance in terms of information loss using three proposed correlation coefficient parameters.