I made this battle-ax in Blender and I imported it into Zbrush. When I split it up and started working on the head of the ax, I turned on D-topo and it started acting weird, as you can see below. I'm not sure what is going on here, this is the second time I've imported from blender and the first project did not have this error when I d-topo'd. Any solutions? I have tried different resolutions to no avail.