Hi, I have crohn's and I have the same thing. I had previous surgery for obstruction of the bowel. At that time my stools were flat wide ribbon like. I was hoping this would improve with surgery but it didn't. I've had chronic diarreha since surgery and now my BM's are like you describe but when I get a little form to them they still tend to be like flat ribbons, or as you describe. The surgeon told me this should improve with time, it still hasn't and a CT scan showed narrowing again. Narrowing can be caused by inflammation or scar tissue closing up the bowel. When your bowel heals more, the inflammation should go down and your bowel movements should improve. If they don't mention this to your doc or GI.

Just curious, did you go for your colonoscopy? Irritable bowel can also cause your intestines to spasm and cause narrowing. My doctor said there may be several causes of altered stool shape. Hope all is well.