How to best remove leaky under-eye veins that cause dark circles? lasers?

Several options: There are several options to treat under eye veins including lasers, sclerotherapy and removal through tiny incisions (microphlebectomy). Each procedure has pros and cons and you should seek someone who has experience in treating veins in this area. Several types of creams such as auriderm and bleaching may help. See a vein specialist.

Veins Beneath Eyes: That depends. When they are spider veins, treatment that involve heat (such as laser or ohmic thermolysis) can be effective. When they are larger veins that are bigger than spider veins, then the treatment can be very difficult. In that situation, laser would end up burning the skin and not be effective. Sometimes mico-phlebectomy surgery can be done to remove them with a formal operation.