The docs I read about 3danisosmooth make it seem like in theory it should be able to do what I need, but it's not clear if it's actually possible.

Basically I have an anatomical T1-weighted brain image from some fancy new motion-resistant pulse sequence (we were scanning kids). For whatever reason, this image type has ended up with the layer of CSF between the brain and skull showing up as very high intensity. I need to do some blurring of the image, but the brightness is getting leaked into the outer surface of the brain, which makes the gyral gray matter look like white matter. I was thinking that some kind of edge-savvy smoothing could help, but when I try 3danisosmooth, it tries to treat my image as a DWI and does the smoothing... anisotropically, which I suppose I should have seen coming.

So, is there a way to take advantage of the edge savviness but do isotropic smoothing?

Thanks!

-dave