Attached Link: WIP vascular tex

I am trying to create my own highly vascular Bump map for a series of bodybuilder images I am creating. Does anyone know how to create a smooth rounded vein. The ones on the lower abdomen look right but those on the shoulders look weird. I have noticed on other attempts that if I use a white brush on a the black and white Bump map it looks elevated in some areas and depressed in others. I believe that I need to adjust some Bump map settings. Any Ideas????