Dr. Ray Radebaugh has advanced the scienceand technology of refrigeration methods bydevising a sophisticated thermodynamic andmathematical procedure for the optimization ofgas mixtures in the mixed-gasJoule Thomson refrigerationprocess. He applied theseprinciples—in collaboration withCryoGen, Inc.—to develop a 3-mm-diameter cryogenic cathetercapable of achieving very lowtemperatures at its tip for use infreezing spots on the heart thatcause arrhythmias. This patentedtechnology has also been used ina uterine catheter that freezes thelining of the uterus in womenwith abnormal bleeding.Technology transfer between Dr. Radebaughand CryoGen, Inc. was established through aCRADA. CryoGen provided the medicalexpertise and guidance for developing the catheter; NIST determined the optimumrefrigeration process compatible with medicalrequirements to develop a prototype.Of the 2.5 million people in theU.S. who suffer from heartarrhythmia, most can besuccessfully treated with Dr.Radebaugh’s heart catheter. Eachyear 120,000 American womenreceive hysterectomies because ofabnormal bleeding. The uterinecatheter developed as a result ofthe CRADA can treat thesewomen, with a success rate ofalmost 90 percent based onclinical trials. In addition,compared to spending weeks recovering froma hysterectomy, women treated with thecatheter can return to normal activities thefollowing day.