Unsealed source radiotherapy relates to the use of soluble forms of radioactive substances which are administered to the body by injection or ingestion. Such substances are typically used for their biological properties, which are similar to their non-radioactive parent substance.
Sealed-source therapy, in which the radioisotope remains in a capsule or metal wire during therapy and is never allowed to dissolve in fluids, is usually referred to as brachytherapy
A review of the subject was published
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