mesentery tissue

the term volvulus actually comes from thelatin word volvere, which means “to roll”. so a volvulus is an obstruction caused bya loop of the intestine that rolls or twists around itself and its surrounding mesentery,which is the tissue that attaches the intestine to the back wall of the abdomen. the three most common types of volvulus area sigmoid volvulus, which happens in the the last part of the large intestine, leadingto the rectum; a cecal volvulus, which happens in the beginning of the large intestine, anda midgut volvulus, which happens in the small intestine. now, a sigmoid volvulus is the most commontype of volvulus, and it can happen in a variety

of settings. one classic one being pregnancy, because thegrowing fetus can cause displacement and twisting of the colon. it can also develop, though, in middle-agedand elderly individuals. this can sometimes happen as a result of chronicconstipation, where a big load of stool can act like a pivot point around which the restof the colon can twist. hirschsprung disease, a disease of the largeintestine that causes severe constipation or intestinal obstruction, therefore raisesthe risk for developing sigmoid volvulus. in addition, there are also abdominal adhesions,where internal scar tissue creates a physical

attachment between two parts of the abdomen,which again serves as a pivot point around which the colon can twist. a cecal volvulus is usually found in youngadults, and usually happens in individuals who didn’t develop their abdominal mesenterynormally during fetal development. since some mesentery contacts may be missingin these individuals, the colon can flop around freely and any large object—like a babyin pregnancy or a load of stool in someone constipated—can act as a pivot point inthe cecum and cause the colon to twist. midgut volvulus is most commonly found inbabies and small children and is the result of abnormal intestinal development in fetuses.

in normal fetal development, the digestivetract starts as a straight tube from the stomach to the rectum. for a little while, a part of the intestineprotrudes from the abdomen into the umbilical cord. once the fetus reaches around 10 weeks, though,the intestine pulls back out of the umbilical cord, and returns to the abdominal cavityand makes two turns, so that it is no longer a straight tube. malrotation happens when the cecum and appendix,which are normally found in the lower right side of the abdomen, stay in the upper rightside.

babies with malrotation can later developtwisting of the small intestine, which is a midgut volvulus. in any type of volvulus, a portion of theintestines becomes twisted and it pinches the lumen shut and results in bowel obstruction,which prevents the normal passage of digested food and water. sometimes, the mesentery can become so tightlytwisted that blood flow to that part of the intestine is cut off, which leads to infarction,or death of the intestinal wall. this can cause a variety of symptoms rangingfrom mild bloating and constipation to severe pain and bloody stools.

in fact, bowel infarction can also cause theintestinal wall to break down and allow the bacteria in the gut to move into the body,which causes sepsis and the potential for cardiovascular collapse. abdominal x-rays are usually used to diagnosevolvulus. these x-rays show the shape of the volvulus,which can look like a bent inner tube or a coffee bean. a barium enema can also be used to show abird’s beak shape, enlarged at one end and tapered at the other end, which is the pointwhere the bowel is twisted. a sigmoid volvulus is usually treated withsigmoidoscopy, an examination of the sigmoid

colon using a set of flexible tubes insertedthrough the anus. if the tissues look normal and pink, the tubesuntwist and decompress the colon to relieve pressure. a similar procedure that goes a bit furtherin, called a colonoscopy, examines the entire colon and can occasionally be used to resolvea cecal volvulus. but a midgut volvulus can’t be treated withcolonoscopy, since it’s even further back in the small intestine. normally surgery is recommended within twodays of receiving treatment, or, in some cases, surgery should be performed immediately, likeif the bowel is severely twisted or if the

blood supply is cut off. the normal surgical procedure involves untwistingthe intestine, if it hasn’t been corrected yet, and attaching the intestine up againstthe abdominal wall to prevent it from twisting in the future. in severe cases, such as infarction, piecesof the intestine have to be removed, a process called bowel resection, before the intestineis reattached. aright, as a quick recap: a volvulus is atwist in the intestine and surrounding mesentery, and it’s most commonly found in the sigmoidof middle-aged and older adults, the cecum of young adults, and the midgut, or smallintestine, of babies.

volvulus results in bowel obstruction andcan sometimes cause infarction, or death, of the bowel tissues. volvulus is diagnosed using x-rays and isusually treated with surgery to remove part of the bowel and attach the bowel up againstthe intestinal wall. thanks for watching, you can help supportus by donating on patreon, or subscribing to our channel, or telling your friends aboutus on social media.