Table 1:

Parameters of different scan protocols

Standards CTCT AngiographyCT Perfusion
BaseCerebrumIntracranialCervicalProtocol IProtocol IIProtocol III
Collimation (mm)20 × 1.220 × 1.264 × 0.664 × 0.620 × 1.220 × 1.220 × 1.2
Table feed (mm)242445,969,7000
Tube current (mAseff)350300160115270200200
Electrical mA350300383417270200200
Potential (kV)1201201001208080120
Rot. time (s)110.50.33111
Scan length (mm)4895250280242424
Scan time (s)6.254.58404040
CTDIvol total (mGy)39.8634.1612.797.9432320970
DLP total (mGy x cm)20334838627710377682330
  • Note:—Table feed indicates table movement per second. Pitch corresponds to the dose-relevant pitch (table feed per total collimation considering the number of detector rows acquired simultaneously). CTDI indicates computed tomography dose index; DLP, dose–length product.