Another thread has reminded me to update this one. The propel implant did in fact delay recurrence of my son's polyps, but it didn't stop it. Instead of having them return within 3 months, it took about 8 months. Now that's a big improvement for us, but not as good as I wanted, obviously. They were indeed still small at the last visit, but his nose started bleeding recently - I'm sure it has to do with the aggravation to his sinuses that winter and its colds bring. He did however continue to culture MRSA in his nasal passages, so for those looking to eliminate that, I don't think it helped. Basically the propel implant is a steroid infused dissolvable cage that is inserted at the time of surgery to decrease the inflammation while your sinuses are healing. The steroids are released through the cage material which disintegrates over a 30 to 60 day time period. The disintegration was not uneventful, but painless. The cage can break apart as it dissolves and on more than one occasion, my son found a small piece in his throat which he would spit out. We also used a sinus atomizer during the following month with Tobi which had been specially formulated for the atomizer. I don't suppose there is anyway to apportion our results between the implant and the atomized antibiotic, but I believe the implant was instrumental.