What is cryotherapy and how it is used?  

Ice therapy. Cryotherapy refers to using cold temperatures to treat a medical condition. For example, prostate cryotherapy is a treatment for prostate cancer in which probes are placed in to the prostate gland to create very cold temperatures to kill cancer cells. Cryotherapy can be used for skin lesions, cervical lesions, and tumors of the prostate, kidney, liver and other organs.
Freezing tissue. Abnormal or cancerous tissue can be frozen and thus destroyed. Has been used in cryoprostatectomies, removal of skin warts and to freeze and destroy enlarged tonsils.