Henry Ford Hospital 

Description: Over the past several years the now universally utilized CT dose indices, CTDIvol and DLP, have come under close scrutiny, motivated in large part by the advent of cone beam and very wide fan beam CT machines. This led to the formation of AAPM Task Group 111 (TG111) which thoroughly examined the CTDI family of dose indices and having done so, formulated a set of recommendations which were included in their report. AAPM Task Group 200 (TG200) has been created to implement these recommendations and as a result a phantom has been designed, built and tested that will address some of the limitations of the current dose index system. In light of some of the confusion regarding the current CTDI indices, a further objective is to clearly distinguish phantom dose measurements from patient dose estimates. This talk will introduce and discuss several new suggested indices.