The laser delivers pulses of light energy which causes the blood within the vein to coagulate, eventually destroying the vessel which is later reabsorbed by your body. Blood flow will then be redirected to veins deeper below your skins surface, where it should be.
Broken capillaries are actually caused by an external disturbance in your skin especially UV damage and trauma to the skin, such as popping a pimple too forcefully, windburns, extreme temperature changes, and excessive drinking or smoking. This external pressure can result in the tiny blood vessels bursting or the valves inside stop working properly. When the valve or veins are damaged or weakened the blood may struggle to flow in the correct direction and then begin to pool inside the vein. Over time this results in broken capillaries and spider veins.
Broken Capillaries or ‘spider veins’ can also occur on the legs. They are usually not painful, but some people may wish to treat them for cosmetic reasons. Spider veins can be blue, purple, or red and may appear in the form of thin lines, webs, or branches.