How does tattoo removal work?
Updated: Jun 28, 2021
BACKGROUND: WHY TATTOOS ARE PERMANENT
The process of tattooing involves the depositing of permanent ink into deep layers of the skin via a tattoo needle. Most professional tattoo ink contains heavy metallic compounds like lead, copper, and mercury. These heavy metals are what enable tattoos to be permanent.
As soon as the tattoo ink is introduced into the skin, the body’s immune system recognizes it as a foreign intruder. White blood cells are naturally sent to the tattooed area in an attempt to destroy and remove the tattoo ink particles. However, the metallic nature of the ink particles makes them severely larger than white blood cells. This size mismatch allows tattoo ink to remain in the skin as the white blood cells are too small to attack (break up) and remove them.
Over time, white blood cells are able to break away and remove small pieces of tattoo ink particles. This partial removal is what causes tattoos to look faded. However, most tattoo ink particles will still be too large to be removed for years after they are introduced in the skin.
STEP 1: TATTOO REMOVAL LASERS BREAK UP TATTOO INK
The common functionality utilized by all tattoo removal lasers is the ability to break large tattoo ink particles into smaller fragments. To do this, tattoo removal lasers use a combination of speed and heat. The laser has to introduce heat to tattoo ink particles in order to expand them. The laser concentrates this heat solely to the ink particles, significantly heating the ink while not effecting the surrounding tissue.
This heat, however, has to be introduced extremely quickly to only part of the particle. With half of the ink particle hot and the other half cold, the opposing forces literally burst the ink particle apart. This is called photothermolysis, which is the same principle used in laser hair removal.
STEP 2: BROKEN (SMALLER) INK PARTICLES ARE REMOVED
With the formerly large tattoo ink particle broken down into smaller sized chunks, the white blood cell army can perform their duty: they absorb the broken ink particles and transport them to the liver where they will be expelled from the body. The tattoo is fully removed (no longer visible) when all tattoo ink is both shattered into smaller pieces and expelled from the body.