anatomy question - omentum vs. mesentery

[mystery girl]

omentum: a fold of peritoneum connecting the stomach with other abdominal organs

mesentery: a fold in the peritoneum that attaches the stomach, small intestine, pancreas, spleen, and other organs to the posterior wall of the abdomen


Q: is this the same structure? or are they different?

 

[Micol]

I can't answer your question, but did you see Oprah this week? I think it was Wednesday's show.

Dr. Oz was on, doing a follow-up show and was answering viewers questions about weight. He brought 2 omentums with him. One from a normal-weighted cadaver and one from an overweight cadaver. In the first case, it looked like loose sack of fascia, in the second case, it was a sack full of fat.

It was very interesting.


Noel

 

[frustrator]

omentum: a fold of peritoneum connecting the stomach with other abdominal organs

mesentery: a fold in the peritoneum that attaches the stomach, small intestine, pancreas, spleen, and other organs to the posterior wall of the abdomen

The difference is what I have underlined above. The mesentery is a section that has been independently named due to its location and purpose. The omentum surrounds, protects, cushions and is connecting everything. It is basically a layer of fat and tissue that serves this purpose. EVERY ONE has this, no matter how low your BMI the fat is needed for protection of the organs. As a Gross Anatomy enthusiast, I have personally disected it, and observed elderly emaciated through highly obese cadavers, and that layer of fat is there. Of course the obese had a lot more... but I was surprized at the appearance in the other extreme.

 

[Favre Fan]

mush,

Here is a pretty nice page with a write up and a cross section to help with a visual. http://www.vivo.colostate.edu/hbooks/pathphys/misc_topics/peritoneum.html

It's been a really really long time since I had cadaver dissection, so I'd hate to mislead you on exact anatomical discussion, which is why I am adding links and pics. But, as I seem to recall, the peritoneum has been re-named (omentum / mesentary) in the different areas where is does different things (as PG mentioned). It all looks basically the same - a yellowish, tissue which you do have to be careful dissecting as it is somewhat thin. There is blood supply running through it and fatty clumps.

Recently I read they are (or may already have done it) talking about transferring part of the omentum (still attached and ferreted through the body and up) to the brain to add blood supply there for Alzheimer's patients.

Here is a nice anatomy class dissection you may like to read over. It will walk you through the abdomen, and if you can get out a good anatomy text at home or look up a dissection text on line, you may enjoy working through it. It's pretty self explanatory, so you probably wouldn't even need a text unless you like visuals. Anatomy Practical Work

This is a pretty nice picture of the mesentery.

This is a pretty nice model to show the greater omentum:

 

[THE]

I can't answer your question, but did you see Oprah this week?
Noel

yup, i always tape dr. oz when he's on oprah. i look at it as a free lecture. he always has good insights and i find i learn something every time he's on. he would be a great a&p instuctor.

i knew about mesentery from school but was not taught what omentum is.

thanks all for your input. i should have read more carefully.

 

[Cassandra L]

Hey -- no problem!

It took me about an hour to locate some good pics and the dissection course for you.

I was lucky to find the first website I gave you up front, but that was probably a fluke. Most of the info on the net I saw just didn't provide a nice concise descriptor.

 

[caramelcappuccino]

anatomy question - omentum vs. mesentery

omentum: a fold of peritoneum connecting the stomach with other abdominal organs
mesentery: a fold in the peritoneum that attaches the stomach, small intestine, pancreas, spleen, and other organs to the posterior wall of the abdomen
Q: is this the same structure? or are they different?

They are different with different functions.
Mes are not only attachemtns for all of the bowel, it is it's vascular source. When we are doing bowel ressections the mes houses all of the arteries we are "clamping and cutting or tying" to release the structur from the mesentery.
Omentum although having some vascualrity(for itself) is for padding and protection.Omentum is the first thing which usually "pops" through a hernia, well second to the peritoneum and muscle. It looks like large yellowish/orange tinged rice crispies held together. Like a small blanket of fat.
As stated above this fat is in everyone no matter how thin.

 

[miranda]

My A&P instructor also was an associate professor of A&P at a medical school..... when we did a class on cadaver study at the med school he started out by telling us that the omentum is like an old fashioned party apron [think 50s-60s] with "fluffs and flurls" and that the mesentery was its "ugly twin sister" sitting out back doing the hard work.......... just the way he described it and it helped make sense of it for all of the testing..... In cadave lab the omentum showed up with lots of coins of fatty tissue while the mesentery was more vascular and glisteny....... hope that helps.