A site marker is provided that includes a generally hollow body defining a cavity. A deployment line within the site marker positions at least one marker element within the body portion. The deployment line has a first end that is fixedly secured to a first end of the body portion and a second end that is secured to a second end of the body portion. The deployment line is pre-biased so as to pull the first end of the body portion towards the second end of the body portion, and thereby expand the body portion.