cryogen /krī″əjən/ [Gk, kryos + genein, to produce] , 1. a chemical that induces freezing, used to destroy diseased tissue without injury to adjacent structures. Cell death is caused by dehydration after cell membranes rupture. 2. (in magnetic resonance imaging ) a chemical used to cool the MRI electromagnet so that the magnet remains superconducting and higher magnified strengths can be achieved. Kinds include carbon dioxide, liquid nitrogen, liquid helium, nitrous oxide. −cryogenic, adj.
