Acquisition Phase

Phase Included

Scan Delay

Respiration Phase

Anatomical Coverage

Non Contrast

N/A

N/A

N/A

N/A

Arterial Phase

Yes

Bolus triggered

Inspiration

To include the entire aortic vasculature

Venous Phase

N/A

N/A

N/A

N/A

Delayed Phase

N/A

N/A

N/A

N/A

Scan Comments: Dual energy is useful for post processing applications such as bone removal and virtual noncontrast. Utilizing these processing techniques, it is possible to eliminate the noncontrast image acquisition phase when following up aortic stent placement.  All scans are performed using the ALARA principle. A 3D Post Processing is performed with this protocol.

 

Technical Parameters

Parameters

kVp

100 / 140

Effective mAs

CareDose

Care Dose Reference mAs

250 / 193

Time (Rotation)

0.5 sec

Average Acquisition Time

10-15 sec

Collimation

32 x 0.6mm

Pitch Value

0.8

Scan Direction

Craniocaudal

Comments: Images are acquired using 100 / 140 kVp setting with a SN filter. CareDose 4D is used to reduce patient exposure. The pitch value should remain below 1.0 to reduce any artifacts during post processing.

 

Reconstruction Parameters

Soft Tissue

Thin Data

Additional Recon

Slice Thickness

 3mm

 0.75mm

 1.5mm

Reconstruction Spacing

 3mm

 0.5mm

 1.0mm

Reconstruction Algorithm

 D30f

 D20f

 D30f

Window Width and Level

 410/10

410/10

 410/10

Reconstruction Comments: Additionally, a lung reconstruction is performed using 3mm x 3mm slices with a B80f algorithm, and a window width and level of 1600/-500. When generating mixed images, the DE composition is set to 0.8. Coronal and sagittal image reconstructions are also performed.

 

Contrast Parameters

Parameters

Contrast Type

Non ionic

Contrast Volume

120ml

Saline Flush

N/A

Injection Rate

4-5ml/sec

Oral Contrast

H2O

Contrast Volume

1000 mL

Comments: Bolus tracking is performed off the abdominal aorta using a 230 HU trigger setting.