How long should we expect for the femtosecond laser to become a practical option for tattoo removal?

Hi there. Kudos to you for even knowing what a femtosecond is! The technology is not there yet and may be years off because it will be prohibitively expensive for providers who would then have to pass that cost on to customers. Even picosecond technology has not drastically improved outcomes in the field of laser tattoo removal.

 It is hard to tell. It is too expensive to purchase and maintain, therefore treatment cost would be high on the patients. Therefore, it probably would not be treatment of choice for majority of patients. Hence, it would not be financially viable to providers.

It is hard to tell. It is too expensive to purchase and maintain, therefore treatment cost would be high on the patients. It probably would not be treatment of choice for majority of patients. Hence, it would not be financially viable to providers.

Im glad you asked this question because patients keep asking about the "new"pico second and I say its been around over a decade its just now commercially available. I wondered how long it would take for the femto to come of age.
The premise of tattoo removal is photo acoustic breaking of the ink. The Q switched lasers have been the gold standard since 1962 and still are. The release the laser rapidly and hard shattering ink like a sledgehammer so to speak. The picos fire faster and initially was thought to break up the ink into even finer particles thus the immune system could take it away easier and faster. however that does not seem to be the case. It seems the fine breakdown of ink in the early stages does not do much to remove a tattoo and the first 4-6 sessions should be done with a standard Q switch and when the ink is very light start the picos. However you still need multiple lasers to effectively remove colored inks and no one laser can do that. 
The current cost of a pico ranges from $250,000 to $350,000 and thats a lot of tattoo to pay that off not to mention a $30,000 a year maintenance fee after year one so I don't think that femto seconds will offer much benefit and the cost already is not justified.

One of the Challenges with shorter pulse durations, Picosecond or Femtosecond laser vs. nanosecond laser, is the limitations in fluence that can be produced at those short pulse durations.   Sometime we can actually get better results with a nanosecond laser compared to a picosecond laser with the same spot size and wavelength just because we can achieve some much higher fluence with the nanosecond laser.  We are currently conducting research on this at the Gateway Aesthetic Institute and Laser Center in Salt Lake City and often find that higher fluences with a nanosecond laser may actually be more effective, keeping all other parameters the same, than a picosecond laser with lower fluence.