Scientists have learned a lot about how the human body works, but our biology remains a mystery in many ways. Researchers have discovered what they're calling a "new organ" within the human digestive system ― a reminder of just how much uncharted territory remains to be discovered within us.
The discovery of the body's 79th organ prompted an update to the famous Gray's Anatomy textbook, which is used by medical students around the world.
People have known about the newly classified organ, known as the "mesentery," for hundreds of years ― Leonardo DaVinci even included it in an anatomical illustration. However, it was thought to be a fragmented structure consisting of separate parts until Dr. J. Calvin Coffey, a professor of surgery at the University of Limerick in Ireland, found evidence that it was one continuous organ.
Based on his findings, outlined in a paper published in November in The Lancet Gstroenterology & Hepatology, Coffey argues that "mesenteric science" should be its own specialized field of medical study.
The mesentery connects the intestines to the digestive tract. More specifically, the organ is a double fold of connective tissue arising from the peritoneum ― the membrane lining the abdominal cavity ― that attaches the stomach, small intestine, pancreas, spleen and other organs to the posterior abdominal wall.
"During the initial research, we noticed in particular that the mesentery, which connects the gut to the body, was one continuous organ," Coffey said in a press release. "Up to that it was regarded as fragmented, present here, absent elsewhere and a very complex structure. The anatomic description that had been laid down over 100 years of anatomy was incorrect."
The anatomic description that had been laid down over 100 years of anatomy was incorrect.Dr. J. Calvin Coffey
"This organ is far from fragmented and complex," he added. "It is simply one continuous structure."
The mesentery's exact function is still unknown. Determining this is the next step for scientists, now that the organ's anatomy and structure have been determined.
However, they do know that the organ keeps the intestines in a particular formation.
"When the mesentery does not attach to the abdominal wall in the manner in which it usually does, then it can twist on its blood supply," Coffey told The Huffington Post in an email. "This causes the blood supply to stop, and the intestine undergoes necrosis or dies. This is incompatible with life."
And if researchers can figure out what abnormal function of the mesentery looks like, they'll have a better shot at understanding how it contributes to disease.
"We need to reinterpret many diseases with a new anatomic model in mind," Coffey said. "When you understand the normal appearing mesentery then you are better positioned to identify abnormalities and the abnormalities that we see in disease."
It's fairly certain that the mesentery is involved in at least some abdominal diseases, according to Coffey, so a better understanding of the organ and its functions could one day lead to less invasive surgeries, fewer surgical complications and faster patient recovery.