Spider Veins vs Varicose Veins There are many differences between spider veins vs varicose veins. The main being that spider veins don't bulge out of the skin, they are generally just small lines that appear underneath the skin. in Public bookmarkswith spider_veins_vs_varicose_veins Note: There are many differences between spider veins vs varicose veins. The main being that spider veins don't bulge out of the skin, they are generally just small lines that appear underneath the skin.