Page 68 - An Introduction to Laser Tattoo Removal
P. 68
Chapter 2 – Fundamentals of Laser Tattoo Removal v1.0
Tattoo Removal Lasers
Q-switched Lasers
The first laser used to successfully remove tattoos without scarring was a Q-switched ruby in the early 1980s in Glasgow, Scotland. This laser output a 694.3 nm wavelength in a 40 nanosecond pulsewidth with a maximum fluence of around 12 J/cm2, in a 5 mm spot size at a repetition rate of 1 Hz (here is the first report from these studies, in 1983).
What’s the difference between ‘active’ and ‘passive’ Q-switches?
Many tattoo laser salespeople will tell you various bits of nonsense about laser technology. This is nothing new. Salespeople will tell you anything to get the sale!!
We covered this topic in a blog post – click here.
There are three Q-switched lasers used in clinical practice today utilising different wavelengths:
QS Ruby laser
The QS ruby laser was the first laser to be used to successfully remove tattoos without scarring by Mike’s clinical team in Canniesburn Hospital, Glasgow in the early 1980s (see references below). While this device was excellent in removing many tattoos, it was hindered by the fact that ruby rods are only efficient in a narrow temperature range. Hence, once they begin to heat up, their laser output energy drops significantly.
Keeping such lasers cool is therefore important. Even with such cooling, it is difficult to fire these systems at more than 1 or 2 Hz – consequently, they are relatively slow when treating larger areas.
A common ‘mythconception’ is that ruby lasers are ‘good’ at treating green ink tattoos, simply because of the red wavelength. This is not quite so simple! In our original studies, we found that some green inks responded very well to this wavelength, while others did not (watch this video).
It is very difficult to generate picosecond pulses from a ruby with sufficient energy to tackle tattoos effectively, which is why no picosecond ruby is currently on the market for this treatment.
________________________________________________________________________ 68
Chapter 2 LEVEL A Laser Tattoo Removal
© The Laser-IPL Guys, 2021