Us Finns have done this for a while now. For eight years we have had a cryotherapy unit at Haikon kartano, a spa located just outside Helsinki. And no kidding either - the temperature in the cryo-room goes all the way down to -166 F.
Here's the spa (in Finnish)
http://www.haikko.fi/fi/etusivu/kylpylae-ja-hoidot/huippukylmae--110degc.php
and here's the Finnish company that makes the cryo-units
http://www.mjgunivers.fi/basic.htm
http://www.mjgunivers.fi/haikko.htm