Pigment that will not break down: change the plan, not the energy

Third session, and the pigment looks almost exactly as it did in the photo from six months ago. The client asks whether something is wrong, and the easiest answer is right there: turn the energy up. It feels logical — if it is not working, give it more. In practice it is usually the moment the risk of blistering, pigmentation changes and altered skin texture goes up, while the pigment stays exactly where it was.

Before deciding that something is going wrong, check what could have been expected at all. In 2009 Kirby, Desai and colleagues reviewed the records of 100 patients whose tattoos had been removed completely. They needed 10 treatments on average, ranging from 3 to 20, six to eight weeks apart. Three sessions without visible change can simply be an early stage of a long series — especially if nobody worked out beforehand how long it might be.

The Kirby-Desai scale comes from the same paper. It scores six features: skin type (1–6 points), location (1–5), colours (1–4), amount of ink (1–4), scarring and tissue change (0–5) and layering, for example after a cover-up (0 or 2). The total correlated clearly with the number of treatments (r = 0.757), and the authors describe a score above 15 as a tattoo that may be difficult to remove. The scale was built for tattoos and Q-switched lasers, so for permanent make-up treat it as a checklist, not a calculator.

Location shows well what energy cannot change. The head and neck score 1 point, the upper trunk 2, the lower trunk 3, the upper arm and thigh 4, and the distal parts of the limbs — forearms, hands, lower legs and feet — 5. The body clears the fragmented pigment, and the pace of that clearing depends on where on the body it sits. The same design on an ankle may need clearly more sessions than on a shoulder blade, at identical settings.

When pigment stalls, start with the calendar. In a paper on ink that unexpectedly stays in the skin (Kirby and colleagues, 2013), the authors note that many dermatologists now recommend at least eight weeks between treatments, and that sessions too close together may interfere with the work of macrophages and raise the risk of scarring. If the series ran every four weeks, energy is not the first suspect.

The second thing is matching the wavelength to the colour. The same authors describe inks that simply do not respond to the wavelength being used, and recommend turning to another one. With permanent make-up this is the spot-test lesson again: a mixture that looked like a single brown at the start may, after a few sessions, reveal a component the current beam does not absorb. More energy at the wrong wavelength means more heat in the skin, not more fragmented pigment.

The third thing is technique within the session. The white discolouration after the first pass shields the ink from the next ones. In the study by Kossida and colleagues (2012), one half of each of 18 tattoos received a single pass and the other half four passes 20 minutes apart — and the second half lightened significantly more. The sample was small and the mechanism is still debated, but the lesson for the plan is practical: sometimes what changes is how the session is run, not the number on the screen.

Before changing the plan, rule out the simple things too. On the device side: calibration, servicing, clean optics and the condition of the crystal. On the client's side: transient hyperpigmentation that is easy to mistake for ink, and health conditions that affect healing, such as treatment that suppresses the immune system. With colours such as white, peach, pink or yellow, the client should know from the start that the pigment may darken and that some colour may remain.

A change of plan is also a change in what you have agreed with the client. Show her photos from each session taken in the same light, and tell her what you checked and what you propose to change: the interval between treatments, the wavelength, the technique, the method or the aim of the series itself. At some point it may be necessary to move from the laser to a remover, or to include both methods in the treatment plan. We discuss that change with the client too, explain the reasons and record it in her file together with her decision. Let’s be honest: we want the unwanted pigment removed as efficiently and safely as possible, but sometimes the honest aim is lightening for a new make-up rather than complete removal. It is a harder conversation than turning a dial, but only after it does the series make sense again.