Any ot the above things you mention could lead to increased vasculature or blood vessels around the eyelids. Anything that increases pressure in the blood vessels can cause exisitng veins to enlarge or cause new veins to form. This can even include straining from weight lifting or just coughing.
These veins may decrease in size in response to less pressure, strain, or trauma but they will not go away on their own.
Large veins can be treated around the eyes using longer wavelength lasers such as the 755 nm alexandrite or the 1064 nm neodynium:YAG lasers with long pulse durations. When treating veins on the upper eyelid or near the eye, a metal intraocular eye shield that is inserted under the lid must be used to protect the eye from any laser injury.
