Updated 05/02/24 CTA Perfusion Reviewed 05/14/25 Indications - stroke, focal neurological deficits, arterial thrombus/occlusion. The following requirements must be met for this protocol to be performed: The patient has stroke-like symptoms. The patient has had symptoms for less than 24 hours. The patient's NIH stroke scale is greater than or equal to 6. A perfusion scan has been approved by a Neurologist (for all patients including ER patients). GENERAL SCAN NOTES Remove any metal from the imaging field of view. Position patient's head so that the orbitomeatal line is perpendicular to table top. Neutral position from side to side. Scan Order: Noncontrast head: Perform routine spiral/helical scan if one has not been performed within last 6 hours. CTA Head +/- Neck: IV Contrast: Administer 75 mL Omnipaque-350. Inject at 4 mL/sec followed by 40 mL saline flush, 20-gauge or larger in forearm or more proximal. Bolus track off aortic arch triggered at 100 HU. Wait 3 minutes between CTA and perfusion scans. Perfusion: IV Contrast: Administer 1 or 2 injections of 50 mL Omnipaque-350 each. Inject at 4 mL/sec followed by 40 mL saline flush, 20-gauge or larger in forearm or more proximal. For scanners requiring 2 scans, do NOT overlap scans. Second scan must start where the last image of the first scan ended. iSchemaView RAPID Support - 650-388-9767 extension 2 or [email protected].

CTA Perfusion SIEMENS PARAMETERS & RECONS 4D Range Scan
Care
Pitch Rot Coll Mode kV mAs Care
Dose kV & Lvl Acq Time mm sec Drive 128 sequential 80 150 off off 150 1.5 1.02 32 1.2 0.285 Force 192 sequential 70 200 off off 48 1.2 0.25 114 1.5 0.50 Scan
Care
Mode kV mAs Care
Dose kV & Lvl Pitch Acq Coll Rot Time Go Up 32 sequential 80 96 off off 0.00 32 0.7 0.8 Go Top 64 sequential 70 132 on on 78 0.50 64 0.6 0.33 Scan

Colli-
Feed / Scan Cycle Dose Detect mation Scan Time Time Mode kV mAs Care
Sensation 64 sequential 80 125 off 24 1.2 0.0 0.5 1.5 Recon
Name of Series Interval Kernel Window Thick Direction PERFUSION 5.0 3.0 Hr36 / H22f cerebrum feet/head Send perfusion images to RAPID for color maps to be generated. GE PARAMETERS & RECONS Scan
Smart
Slice
Beam
Dose
Pitch Speed Rot
ASIR Type SFOV kV Manual mA mA Thick Coll Time Red 20 8i LS VCT 64 axial head 80 125 off 5.0 40 0.8 20 Window
Recon Name of Series Thickness Interval Recon
Algorithm Width/Level Direction PERFUSION SLAB 1 5.0 0.0 full 150/35 feet/head PERFUSION SLAB 2 5.0 0.0 full 150/35 feet/head PHILIPS PARAMETERS & RECONS Scan
3D

Colli-
Feed / Scan Cycle Detect mation Scan Time Time Mode kV mAs Dose
Index Dose Incisive 128 axial 80 100 NA NA 0.5 64 0.625 0.0 2.0 Name of Series Thick Interval Filter Window iDose Recon
Direction PERFUSION SLAB 1 10.0 10.0 UA brain 1 feet/head PERFUSION SLAB 2 10.0 10.0 UA brain 1 feet/head