Patent Number: 051909901
Section: claims

1. A method for shielding healthy tissues during radiation therapy which comprises covering those tissues during therapy with a radiation shield for use during high energy radiation therapy which is custom fitted to the conformation of tissue at the site of intended use, comprising the polymerized form of a composite of a manually moldable elastomeric material and a filler powder of spherical particles of non-toxic, non-radioactive high atomic density metal or metal alloys. 2. A method as in claim 1, wherein the elastomeric material is an addition-reaction polymerizable silicone impression material. 3. A method as in claim 1, wherein the elastomeric material is a silicone or vinyl polysiloxane composition. 4. A method as in claim 1, wherein the spherical particles of metal or metal alloy are of an average diameter between about 1 .mu.m and about 100 .mu.m. 5. A method as in claim 1, wherein the spherical particles of metal or metal alloy of of an average diameter less than 40 .mu.m. 6. A method as in claim 1, wherein the spherical particles of metal or metal alloy are made by atomization. 7. A method as in claim 1, wherein the spherical particles of metal or metal alloy are selected from the group consisting of Sn-Sb, Ag-Cu, Cu-Al, Au-Cu, Sn-Bi, and Ag-Pd. 8. A method as in claim 1, wherein the spherical powder of metal or metal alloy constitutes between about 50 and about 95 weight percent of the composite. 9. A method for shielding healthy tissues during radiation therapy which comprises covering those tissues during therapy with a radiation shield prepared by a method comprising mixing a powder of non-toxic, non-radioactive high atomic density metal or metal alloy spherical particles with a precursor for a manually moldable polymerizable elastomeric material to form a composite, shaping the composite with manual pressure into the appropriate configuration to shield the healthy tissues of a patient surrounding an area to be subjected to radiation therapy, and polymerizing the elastomeric material.