Acquisition Phase

Phase Included

Scan Delay

Respiration Phase

Anatomical Coverage

Non Contrast

 Yes

  N/A

 inspiration

lung apices through the bases to include the diaphragm

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: If IV contrast is indicated, venous phase imaging is performed using a scan delay based on the patient's age, weight, and body habitus. All scans are performed using the ALARA principle.

 

Technical Parameters

Parameters

kVp

100

Effective mAs

See chart

Care Dose Reference mAs

See chart

Time (Rotation)

0.33 sec

Average Acquisition Time

4-5 sec

Collimation

64 x 0.6mm

Pitch Value

2.5-3.0

Scan Direction

Craniocaudal

Comments: The effective mAs is determined by a weight based chart for patients under 100 lbs. CareDose can be used with a 125 reference mAs.

 

Reconstruction Parameters

Soft Tissue

Thin Data

Lung

Slice Thickness

3mm

0.75mm

3mm

Reconstruction Spacing

3mm

0.5mm

3mm

Reconstruction Algorithm

B30f

B20f

B80f

Window Width and Level

410 / 10

410 / 10

 1600 / -500

Reconstruction Comments:  Coronal and sagittal reconstructions are performed. A Hires 1mm x 10mm recon is also performed using a B80f reconstruction algorithm and a window width and level of 1600 / -500

 

Contrast Parameters

Parameters

Contrast Type

Non ionic

Contrast Volume

 weight based

Saline Flush

 N/A

Injection Rate

 1.5-3ml / sec

Oral Contrast

 N/A

Contrast Volume

 N/A

Comments: The scan delay is determined both in part by patient age, IV access, and injection rate.

 

Other Comments: The effective mAs for a pediatric Hi Res Chest CT is calculated using the following chart.

Weight (kg)

Effective mAs

 CareDose

 <15

 45-65 mAs

 

 15-24

 70-85 mAs

 

 25-34

 85-95 mAs

 

 35-44

 100-110 mAs

 

45<

CareDose

125 ref mAs