64 Slice MDCT Protocols: Carotid CTA

Specific anatomic region

 Carotid CTA

Application

 Carotid stenosis

Author

Elliot K Fishman, MD

Reference Source

JHU Protocol

Scanner Used

Siemens Sensation 64

KV/Effective mAs/ Rotation time (sec)

 120/ 200 / .33

Detector Collimation (mm)

 .6

Slice thickness (mm)

 .75

Pitch

 .9

Kernel

 B20

Reconstruction interval

 .5

Image order (acquisition)

Cr-ca

Oral contrast

 N/A

IV contrast volume and type

 100 cc of Omnipaque 350 or Visipaque 320

Injection rate

 4cc/sec

Scan delay (sec)

 15 sec empirical delay / bolus tracking

3D technique used

 VRT/MIP

Comment:

  • Bolus tracking - ROI placed at aortic arch, threshold set at 70 HU.
  • 3D mapping using both VRT and MIP are part of the standard carotid artery protocol to define the presence, location, and extent of stenosis.
  • We do not routinely do a non-contrast study.