Scanogram (AP–Lat) | Basal Scan (Optional) | Contrast Scan | |
---|---|---|---|
Coverage | Sternum to midhead | Midneck to cover the bifurcation | From aortic arch to midhead |
Scan mode | Scanogram | Helical | Helical |
Start time | NA | Bolus trackingb | |
Range | 500 mm | 8 cm | Variable |
Collimation | NA | 0.5 × 80 | 0.5 × 80 |
Pitch | NA | 1 | 1 |
kV | 120 | 120 | 120 |
mA | 50–200c | 350 | 350 |
Rotation time | NA | 0.275 second | 0.275 second |
Direction | NA | Caudocraniald | Caudocraniald |
Slice thickness | NA | 1 mm | 1 mm |
Slice interval | NA | 0.5 mm | 0.5 mm |
FOV | Wide | 20 cm | 20 cm |
Filter | NA | Sharp (FL03) | Sharp (FL03) |
CTDI (mGy) | – | 15 | 15 |
DLP (mGy × cm) | – | 0.6 | 0.6 |
Amount of CM | – | – | 40–50 mLe |
IDR | – | – | 1.4–1.5 g I/s |
Concentrationf | – | – | 370 mg I/mL |
Flow ratef | – | – | 4 mL/s |
Note:—NA indicates not applicable; AP, anteroposterior; Lat, lateral; CTDI, CT dose index; DLP, dose-length product; IDR, iodine delivery rate; CM, contrast medium.
↵a Toshiba Medical Systems, Tokyo, Japan.
↵b Position of bolus tracking: aortic arch, threshold 100 HU.
↵c 50 mA in AP and 200 in Lat.
↵d Craniocaudal is also possible.
↵e Variable according to the concentration.
↵f Concentration × flow rate = IDR. The parameter to be considered is IDR.