Summary
CT dose depends on geometry, filtration and shape of the dose profile
Absorbed dose in CT is quoted using the CTDI
CTDI must be corrected for pitch or couch increment to obtain dose from a series of slices
Different definitions of CTDI exist and are used in different applications
DLP gives an approximation of radiation risk
Effective dose is used for more accurate risk estimates
DRLs in CT are set in terms of CTDIw and DLP