I have lymphedema in both of my legs. When I started therapy last year my therpist used cotton rolls in the beginning then switched to foam rolls. I am now done with the therpist and since then I've been using the foam and been buying the the foam rolls on the internet every 6 months or so. I went to a store this time and they had only the cotton rolls. They said no one ever asked for the foam ones. So it got me thinking what is the difference between the cotton ones and the foam? Which one is better to use and why?