I had severe abdominal pain a couple weeks ago. Do you know what a mesentery is?

Background: I've had a lot of stomach surgeries for weight loss, and had a subtotal colectomy. After one surgery I started getting bad bloating and constipation. That's been going on for 5 years and I have to be careful about what I eat, that it's ground up because of this problem. I pretty much recline all the time in a chair since I've had this problem. A couple weeks ago I had a horrible pain in my lower right abdomen. I went to the ER and they did a CT. They said the mesentery was hazy in the first CT. Then they ordered another CT with contrast, but this was 8 hours after the pain started and by this time it actually stopped. This CT showed no problems. I've had other tests and nothing showed anything. Upper GI with small bowel follow through showed nothing. Colonoscopy, Endoscopy showed nothing. I did have a sitz marker test that showed a delay as I didn't p the markers for over 14 days. That's when I had the subtotal colectomy. I just can't believe that I can't get normal again. This past 5 years has been horrible having to deal with this. I don't know what the mesentery actually is for sure...if it's the artery or what. If it is the artery, can that go away. Could the haziness have been a partial bloackage which is how it felt to me.