1. A medical system, comprising: a medical device adapted to be inserted into a target object and configured to remove a lesion within the target object, the medical device comprising a needle including a pipe therein and a fluid provider configured to provide fluid to the pipe; an ultrasound data acquisition unit configured to transmit and receive ultrasound signals to and from the target object to output ultrasound data; and a processor in communication with the ultrasound data acquisition unit, the processor being configured to form a brightness mode image and a color Doppler image corresponding to flow of the fluid based on the ultrasound data, detect a position of the needle from the brightness mode image based on the color Doppler image and perform an image processing for making prominence of the brightness mode image based on the detected position of the needle, wherein the fluid provider, the ultrasound data acquisition unit, and the processor are implemented as hardware components.