Acquisition Phase

Phase Included

Scan Delay

Respiration Phase

Anatomical Coverage

Non Contrast

Yes

N/A

N/A

Bass of skull through vertex

Arterial Phase

N/A

N/A

N/A

N/A

Venous Phase

N/A

N/A

N/A

N/A

Delayed Phase

N/A

N/A

N/A

N/A

Scan Comments: The F/U shunt protocol is performed using a low dose sequential scan to limit patient exposure. Isocentering and properly positioning the patient within the gantry is key to image quality and limiting the radiation dose. If the patient is unable to hold still for the duration of the exam, a low dose spiral study can be performed instead to decrease the scan time. All scans are performed using the ALARA principle.

Technical Parameters

Parameters

kVp

120

Effective mAs

Use dose reduction software

Care Dose Reference mAs

150

Time (Rotation)

1.0 sec (Full) / 3.0 sec cycle time

Average Acquisition Time

10 sec

Collimation

128 x 0.6mm

Table Feed

34.5 mm

Scan Direction

Caudocranial

Comments: Dose reduction software is used to reduce patient dose. The F/U shunt protocol is performed using a low dose sequential scan to limit patient exposure.

Reconstruction Parameters

Soft Tissue

Bone

Thin Data

Slice Thickness

5 mm

5 mm

 0.75 mm

Reconstruction Spacing

5 mm

5 mm

 0.5 mm

Reconstruction Algorithm

J30s (3)

J70h (3)

J30s (3)

Window Width and Level

100/30

2500/500

100/30

Reconstruction Comments: 3D MPR’s can be performed to correct positioning.

Contrast Parameters

Parameters

Contrast Type

N/A

Contrast Volume

N/A

Saline Flush

N/A

Injection Rate

N/A

Oral Contrast

N/A

Contrast Volume

N/A

Comments: IV contrast is not typically necessary for this exam.