CT Protocols: (Brain, ENT, Spine, Vascular) - Department of Radiology

116 Revised 7/22/09 (Gentry/Ranallo)
Vascular Imaging: Aneurysm (Hi-Res COW): (Nontraumatic SAH, Known Aneurysm)
(Protocol – Adult: # 1.8 – Pediatric: # 11.20 & 11.21)
Billing:
1. CT Head with and without
2. CTA Head with contrast
3. Contrast
Setup:
DFOV: 18 cm
Exam: Part 1:
Part 2:
Option:
Part 3:
1. Patient Supine, AP and lateral scouts, No Gantry Tilt
2. Extend the scouts to include the aortic arch for smart prep.
3. 16 or 64 slice scanners
4. Patient Positioning: Tilt the patient’s head so that a line connecting the lateral canthus of
the eye and the EAC is perpendicular to the CT tabletop (see below).
Routine Head CT without contrast (helical)
CTA Head Only
1. Scan Area From the top of the lateral ventricles to the bottom of the C2 vertebrae (use
Part 1 to select the top slice, see below)
2. Scan direction scan from top to bottom
3. Contrast Adult: 150 ml of Iohexol 300 (24 g Iodine) with a 50 ml saline chase
Peds: 1 ml/lb (2 ml/kg) of Iohexol 300 with a 10-25 ml saline chase
4. Injection Rate Adult: 4 ml per sec (26.6 sec contrast injection time) (43.3 sec contrast transit time)
Peds: 2.0-2.5 ml/sec
5. Smart Prep Over aortic arch (initiate the scan at the entry of contrast in the aortic arch)
CT Perfusion (see perfusion page for details)
1. Wait at least 5 min from start of CTA contrast inject before beginning Perfusion Injection.
2. Contrast 40 ml of 370 nonionic contrast (14.8 g Iodine) with 30 ml saline chase
3. Injection Rate Adults: 5 ml per sec with a 5 sec prep delay
Pediatric: 3-5 ml per sec (Depends on size of needle and age of patient)
4. Prep Delay 5 seconds
Routine Head CT with contrast (helical)
1. If Perfusion is done, perform immediately after the Perfusion Imaging - No need to wait 5 min.
2. If Perfusion is not done, perform scan at least 5 min after start of CTA contrast injection
Networking:
Processing:
1. ALI store, CTAW2 and CTAW3
1. Thick Slab Reformat Instructions (See Appendix 1)
2. Perfusion Analysis (3D Lab) (See Appendices 3 and 4)
3. 3D Intravascular Image Analysis on ADW workstation (Do on Stent Cases)