Your pouch is still part of your stomach so yes, it can stretch. Usually it's from over-filling it by eating portions bigger than the pouch holds. The stomach is very elastic and will stretch to accommodate what you put in it. If you only over-eat on occasion it will likely go back to normal, but in our case, food has no place to go until it digests enough to go through the opening of the band. If you over-fill your pouch often, over time, it will stretch and stay that way. If the small pouch expands past the width of your band that's called a dialation. What you're doing is creating a bigger pouch that will hold more food which basically defeats the purpose of having the band.
If a pouch dialation is detected, (only visible by floro or and upper GI), the protocol is to empty the band so food will pass through easily in hopes that the elastic stomach material will snap back in place. If caught early enough it usually will, but if you've abused your pouch over a long period it may not go back all the way. The other thing that can happen is that you over-fill your pouch so much that food is backing up into your esophogus which can also cause the same thing to happen there which is called an esophogeal dialation.
The bottom line and key to keeping your pouch small, like it's intended to be, is to keep your portion size to less than 1 coup of food at each meal or less than 4 ounces.
Portion control is important in so many ways for the band patient!
You're doing great btw! Congratulations on your WL!
Lap Band surgery Nov. 2008, SW 335. Lost 116 lbs. LB removal May 2013 gained 53 lbs. Revisied to RNY October 14, 2013, new SW 275.