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.
How often you have a bowel movement varies, but people normally have as many as three bowel movements a day to as few as three a week. You may be constipated if you have fewer bowel movements than are normal for you. In addition, constipation may involve stools that are difficult to pass because they're hard, dry or small. However, before turning to laxatives, try these lifestyle changes to help with constipation: