My son's forehead vein pops out all the time, why is this? How do you fix this without surgery? (Photo)

I perform sclerotherapy on nearly all of these large forehead veins but inform patients that more than 1 session is necessary. I have had better success with 1 treatment when patients wore head bands over the forehead for a week after the procedure - like NBA basketball players.Another technique is microphlebectomy. 

For this vein there are 3 options--leave alone, removal through micro incisions or sclerotherapy. Micro incision removal would be my procedure of choice.