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

Aortic arch through Circle of Willis

Venous Phase

N/A

N/A

N/A

N/A

Delayed Phase

N/A

N/A

N/A

N/A

Scan Comments: If bone removal is necessary, a Dual Energy CTA Carotid protocol should be used to optimize post-processing. All scans are performed using the ALARA principle. 3D post-processing is performed with this protocol.

 

Technical Parameters

Parameters

kVp

100/Sn140

Effective mAs

CareDose

Quality Reference mAs

270/270

Time (Rotation)

0.28 sec.

Average Acquisition Time

5-7 sec.

Collimation

128 x 0.6 mm

Pitch Value

0.7

Scan Direction

Caudocranial

Comments: Images are acquired using 100/140 kVp setting with a Sn filter. CareDose is used to reduce patient dose. A 0.28 rotation time is used to increase scan speed to avoid venous contamination.

 

Reconstruction Parameters

Soft Tissue Open Field

Bone Open Field

Thin Data Open Field

Hi Res Brain Only

Slice Thickness

 3 mm

3 mm

 0.75 mm

0.75 mm

Reconstruction Spacing

 3 mm

3 mm

 0.5 mm

0.5 mm

Reconstruction Algorithm

Qr40 (3)

Br59 (3)

Qr40 (3)

Br51 (3)

Window Width and Level

350/50

2500/500

350/50

700/80

Reconstruction Comments: When generating mixed images, the DE composition is set to 0.8.

 

Reconstruction Parameters

Thin Data Carotid Mag

Sliding MIP True Axial (Brain Only)

Sliding MIP Coronal (Brain Only Aligned to Basilar Artery)

Sliding MIP Sagittal (Brain Only)

Slice Thickness

0.75 mm

16 mm

16 mm

16 mm

Reconstruction Spacing

0.5 mm

3 mm

3 mm

3 mm

Reconstruction Algorithm

Bv38 (3)

Br51 (3)

Br51 (3)

Br51 (3)

Window Width and Level

350/50

700/80

700/80

700/80

Reconstruction Comments: When generating mixed images, the DE composition is set to 0.8.

 

Contrast Parameters

Parameters

Contrast Type

Non-ionic

Contrast Volume

60-100 mL

Saline Flush

N/A

Injection Rate

5-6 mL/sec.

Oral Contrast

N/A

Contrast Volume

N/A

Comments: Bolus tracking is performed off the aortic arch using a 25 HU trigger setting.