ABSTRACT
Dosimetry is required for optimizing targeted alpha-particle therapy (TAT), as it is true for any radiation therapy. Current methods only partly overcome major obstacles caused by complex decay chains (that often involve alpha-emitting daughter radionuclides) as well as the short range of the emitted alpha particles. While TAT dosimetry is far less accurate than what is achieved for external-beam radiotherapy, the field is rapidly developing. A medical physicist will need to interact with radiochemists, histopathologists, biomedical scientists and other health professionals to gain insight into the time-dependent distribution of the alpha-emitting compound throughout the body. Simple measurements of gamma photons or characteristic x-rays often provide useful information in attempting to quantify activity uptake and can together with pharmacokinetic modelling and microdosimetry improve the accuracy of the dosimetry. This chapter describes the methods available for providing useful estimates of absorbed dose from alpha-emitters.
