Freezing agents have been used in a diversity of skin conditions since White's first report of the use of liquid air in 1899.1 Pusey, in 1907,2 popularized the use of solid carbon dioxide only after observing the applications of liquid air and liquid O2 in dermatology. As the liquefied gases became more readily available, liquid O2 was more commonly used. Irvine and Turnacliff, in 1929,3 described its use on common warts, and Kile and Welsh, in 1948,4 reported using it in the treatment of over 1,000 cases of keratoses, warts, etc.
Because of its safety and somewhat lower temperature, liquid N2 has gradually supplanted liquid O2 and liquid air in dermatology. Allington, in 1945,5 described its use on cases of verrucae and also many other uses.
At present, liquid N2 is used by many dermatologists in the larger medical centers.
GRIMMETT RH. Liquid Nitrogen TherapyHistologic Observations. Arch Dermatol. 1961;83(4):563–567. doi:10.1001/archderm.1961.01580100027004