CT — Craniu preoperator (MCB)

Updated 03/22/25 CT Head Pre-Surgical Reviewed 05/14/25 Also known as - stealth protocol, brain lab protocol. Indications - pre surgical imaging. GENERAL SCAN NOTES Remove any metal from the imaging field of view. Position patient's head so that the line connecting the lateral canthus of the eye and the EAC is perpendicular to the CT tabletop. For all adult head studies, it is important for image quality purposes to position the patient in the center of the scan field. Use the lateral laser beam to make sure that the patient is positioned in the center. Topogram - C1 vertebrae through top of head. Craniocaudal scan coverage - C1 vertebrae through top of head. Avoid scanning the lens of the eyes. Adjust FOV (field of view) on topogram to smallest without cropping anatomy (usually 28 to 32 cm). Include from anterior nose tip through posterior skin (anterior to posterior coverage). Use a square matrix (either 256 x 256 or 512 x 512). IV Contrast: 100 mL Omnipaque-300, inject at 1 mL/sec, 3 mins scan delay. For GE scanners, it is essential for the 1st recon thickness on the scanner to match the 1st recon thickness in this protocol book for the prescribed Noise Index to be valid. The 1st recon should generally be the thickest recon in the protocol.

CT Head Pre-Surgical SIEMENS SPIRAL SCAN PARAMETERS & RECONS Scan
Care
Scan
Acq Coll Rot Mode kV mAs Care
Dose kV & Lvl Pitch Time Time Sensation 16 spiral 120 320 on NA 0.55 16 1.5 1.0 9.1 Go Up 32 spiral 130 230 off off 0.55 32 0.7 1.0 9.7 Sensation 64 spiral 120 380 on 0.85 64 0.6 1.0 7.4 NA Definition 64 spiral 120 350 on on 0.55 64 0.6 1.0 11.4 Go Top 64 spiral 120 265 off 0.55 64 0.5 1.0 6.8 off Drive 128 spiral 120 332 on on 0.55 128 0.6 1.0 5.7 Force 192 spiral 120 332 on on 0.55 192 0.6 1.0 3.8 IR
Recon
Name of Series Thick Interval Kernel Window Lvl Direction AX SOFT 4.0 4.0 Hr40 / H31s cerebrum 3 feet/head TRUE AX SOFT 4.0 4.0 Hr40 / H31s cerebrum 3 feet/head TRUE AX THINS 1.0 1.0 Hr40 / H31s cerebrum 3 feet/head Protocol specific recon. COR SOFT 3.0 3.0 Hr40 / H31s cerebrum 3 front/back SAG SOFT 3.0 3.0 Hr40 / H31s cerebrum 3 left/right AX BONE 4.0 4.0 Hr64 / H70s bone 3 feet/head Send the above recons on the pre contrast scan (if without only) or on the post contrast scan (if IV given). *Send as close to 1.0 mm thick 1.0 mm spacing recons if your scanner cannot do exactly 1.0 x 1.0 mm. Send only the following recon on the pre contrast scan (if without and with). feet/head AX SOFT PRE 4.0 4.0 Hr40 / H31s cerebrum 3

CT Head Pre-Surgical GE HELICAL SCAN PARAMETERS & RECONS Scan
Smart
Slice
Beam
Dose
ASIR Scan
Type SFOV kV mA
Range Noise
Index mA Thick Coll Pitch Speed Rot
Time Red Time 10 0.562 5.62 0.8 NA NA LS 16 helical head 120 50-250 3.54 on 5.0 17.1 Opt 540 helical head 120 50-250 3.54 on 5.0 10 0.562 5.62 0.8 NA NA 17.1 on 5.0 LS VCT 64 helical head 120 50-210 2.47 30 30 7.9 20 0.531 10.62 0.7 Disc VCT 64 helical head 120 50-210 2.47 on NA 7.9 5.0 20 0.531 10.62 0.7 NA RECONS Window
Recon
Name of Series Thickness Interval Recon
Algorithm Width/Level Direction AX SOFT 5.0 5.0 std full 80/40 feet/head Must be first recon. TRUE AX SOFT 5.0 5.0 std full 80/40 feet/head TRUE AX THINS 1.0 1.0 std full 80/40 feet/head Protocol specific recon. COR SOFT 2.5 2.5 std full 80/40 front/back SAG SOFT 2.5 2.5 std full 80/40 left/right AX BONE 5.0 5.0 bone full 2500/480 feet/head Send the above recons on the pre contrast scan (if without only) or on the post contrast scan (if IV given). *Send as close to 1.0 mm thick 1.0 mm spacing recons if your scanner cannot do exactly 1.0 x 1.0 mm. Send only the following recon on the pre contrast scan (if without and with). AX SOFT PRE 5.0 5.0 std full 80/40 feet/head

CT Head Pre-Surgical PHILIPS HELICAL SCAN PARAMETERS & RECONS Scan
Dose
3D
Rot Scan
Mode kV Avg
mAs Index Dose Pitch Detect Colli Time Time Incisive 128 helical 120 310 37 on 0.70 64 0.625 1.0 4.3 RECONS Recon
Name of Series Thick Interval Filter Window iDose Direction AX SOFT 4.0 4.0 UB brain 1 feet/head TRUE AX SOFT 4.0 4.0 UB brain 1 feet/head TRUE AX THINS 1.0 1.0 UB brain 1 feet/head Protocol specific recon. COR SOFT 3.0 3.0 UB brain 1 front/back SAG SOFT 3.0 3.0 UB brain 1 left/right AX BONE 4.0 4.0 YB bone 1 feet/head Send the above recons on the pre contrast scan (if without only) or on the post contrast scan (if IV given). *Send as close to 1.0 mm thick 1.0 mm spacing recons if your scanner cannot do exactly 1.0 x 1.0 mm. Send only the following recon on the pre contrast scan (if without and with). AX SOFT PRE 4.0 4.0 UB brain 1 feet/head