Would a low dose of Accutane eliminate the risk of purging?

I've been on dianette for acne for a very long time but due to my age my GP has said I've got less than a year left on it. I still get cystic acne but it's not too bad. Every time I've tried coming off it my skin has been terrible with cystic acne and I've had some bad scarring as a result. I think I'll have to give in and take accutane but as I've spend 1000s on treatments for my indented scars I really don't want to purge. Would a very low dose over a long period of time eliminate the risk?.