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.
Most people do not give their bowel movements much thought. This is why it does not come as a surprise that many do not know what a ânormalâ bowel movement should look like and how often they should have a bowel movement. The fact of the matter is that there is no specific definition of a normal bowel movement.