SF 6 is used as a contrast agent for ultrasound imaging. Sulfur hexafluoride microbubbles are administered in solution through injection into a peripheral vein. These microbubbles enhance the visibility of blood vessels to ultrasound.F 6 is used as a contrast agent for ultrasound imaging. Sulfur hexafluoride microbubbles are administered in solution through injection into a peripheral vein. These microbubbles enhance the visibility of blood vessels to ultrasound.
Once constipation (no bowel movement) has gone on for some time, the result can be what is known as an impacted bowel (sometimes called fecal impaction). Essentially, this means that a large lump of dry, hard stool is stuck inside your rectum.
A bowel movement is the actions of the terminal colon and rectum that help to push the stool out when you defecate. It consists of four steps: - First there are constrictionâ¦s of the colon that push stool down to the terminal colon and rectum.