Art Graininess Help

[Kinetic]

It's been a while since I posted any work on here, but I really need some help to fix a problem I have in my current piece. Any graphics experts' advice is welcomed.

I was just screwing around in photoshop with an old minimalism image but it started to turn into a trendwhorish abstract thing, but I thought it looked cool, so I ran with it. The problem is, it's pretty grainy at the edges, and I've tried alot of different techniques but can't get rid of it without blurring the crap out of it. I even used to smudge tool to remove some of it, but it's still not enough. Any ideas?

[url="http://chriscole.250free.com/radi.png"]http://chriscole.250free.com/radi.png[/url]