In this digital era medical image security is important as they carry highly personal data, which should be kept away from the hackers and unauthorized persons, as these images are transmitted/stored among hospitals and also by health insurance companies. Chaos based cryptography/security has been increased in recent years. In this paper we proposed an algorithm, in which security can be given along with effective compression of image. Our process of providing image security starts with compressing the image using EZW. The output sequence of EZW is converted to 2D and on the 2D data we are going to apply row wise and column wise scrambling algorithm based on chaos. In this paper we are also going to discuss about part of EZW in providing additional security to image along with its main function of compression.