Acquisition Phase

Phase Included

Scan Delay

Respiration Phase

Anatomical Coverage

Non Contrast

Yes

N/A

N/A

To include mastoid air cells through petrous ridges

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: Careful positioning is important to avoid unnecessary exposure to the eyes. All scans are performed using the ALARA principle

 

Technical Parameters

Parameters

kVp

120

Effective mAs

CareDose

Care Dose Reference mAs

280

Time (Rotation)

1.0 sec

Average Acquisition Time

16-18 sec

Collimation

16 x 0.3mm

Pitch Value

0.6

Scan Direction

Caudocranial

Comments: Decreasing the display field of view for both the right and the left temporal bones will increase spatial resolution. Scans times are significantly longer than routine scans due to a small collimator size coupled with a low pitch value to increase resolution.

 

Reconstruction Parameters

Soft Tissue

Thin Data

Bone

Slice Thickness

 2mm

 0.4mm

 0.4mm

Reconstruction Spacing

 2mm

 0.2mm

 0.2mm

Reconstruction Algorithm

 U30u

 U70u

 U70u

Window Width and Level

 350/20

3500/500

 3500/500

Reconstruction Comments: Reconstructions are done both bilaterally and coned down for each temporal bone. Coronal and sagittal image reconstructions are also performed.

 

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.