Current, Limits and TCM
I currently try to understand the scanner setting, different vender use different method to set AEC. what is current? Is it the reference current and limit is the maximum current. OR is it the min and max of AEC. Also ho
I currently try to understand the scanner setting, different vender use different method to set AEC. what is current? Is it the reference current and limit is the maximum current. OR is it the min and max of AEC. Also how to find TCM for different machines. Any answer would be helpful. Thanks.
NCI Dose Team response
"Current" is the reference tube current in mA and "Limit" is the current limit set by your CT scanner. The TCM algorithm implement3ed in NCICT is based on a generic attenuation model and the computational human phantoms so it's not representing a specific scanner or vendor algorithm. We are working to compare physical phantom-based measurements with this generic model to better understand how the generic model can be translated to different vendors' algorithms.
Community reply
Can I ask about the "Rotation time" is that equivalent to the exposure time?
NCI Dose Team response
Yes, rotation time is equivalent to exposure time. Current (mA) x rotation time (s) = mAs. Also, keep in mind that using a pitch not equal to one will effect the effective mAs. Effective mAs = mAs/pitch.