Q-switched Nd:YAG laser tattoo removal works through selective photothermolysis, laser pulses in the nanosecond range fragment tattoo ink particles into smaller pieces that the body's lymphatic system clears over weeks to months. The two operative wavelengths cover the standard ink palette: 1064 nm targets black, dark blue, and dark green ink (the commonest tattoo colours); 532 nm targets red, orange, and yellow.
Wavelength selection by ink colour is non-negotiable, using the wrong wavelength either fails to fragment the pigment (waste of session) or causes paradoxical darkening (particularly with iron-containing pink and red inks, or with white/flesh-coloured inks used in cover-ups). DermaVue's protocol includes a test patch for any tattoo with white, fluorescent, or unknown-pigment areas before treating the full tattoo.
The R20 multi-pass technique, four laser passes per session at 20-minute intervals (originally published by Kossida et al, JAAD 2012), accelerates clearance for amateur and thin-line tattoos by allowing whitening (epidermal vapourisation bubbles) between passes to resolve, then re-treating the previously hidden pigment. R20 doubles to triples the per-session pigment clearance versus standard single-pass for receptive tattoo types, though it does not change the requirement for 6-8 week between-session intervals (lymphatic clearance is the rate-limiting step, not laser interaction).
Session count expectations: amateur single-colour tattoos clear in 3-6 sessions; professional multi-colour tattoos take 6-12 sessions; cosmetic tattoos (eyebrow, eyeliner) require careful staging with smaller test areas because of the iron-oxide-darkening risk and the cosmetic stakes of the location.