So, I tried to look for more information about it...
And I found this:
http://www.koreamed.org/SearchBasic.php?RID=0009JKSC%2F2002.18.1.7&DT=1
The results of a study, where they measured the anal caliber of people with chronic AF's and compared them to those of normal people. So, it seems that that scary word, stenosis, is just another word for tight anal sphincter, since 84% of the people in the study with chronic AF's had it. And LIS got rid of it for most people.
I've definitely been worried that I have it, since I struggle so much sometimes, and my stool diameter is definitely smaller than it used to be before I had problems.
Come on LIS, save my ass...