CT HEAD - SEQUENTIAL

***HEAD SEQUENTIAL FOR PATIENTS UNDER 20 YEARS OLD. HEAD SPIRAL FOR ALL OTHER PATIENTS***

INDICATIONS: WithOut:Headaches, cerebrovascular accident, subdural hematoma, trauma

With:Tumor, metastases

PATIENT PREP:WithOut:No Prep

With:NPO for solid foods, water only, for 4 hours prior to scan

IV CONTRAST: Perform as directed by the supervising radiologist.

WithOut:None

With:80mL Isovue 370. Hand inject or 2 mL/second power injector.

ORAL CONTRAST:None

POSITIONING: Head First Supine.

GANTRY TILT/Axial Plane: 25 degrees Caudad to Reid’s Baseline.

POSITIONING:Superimpose the supraorbital ridge and the inner table of the skull at the foramen magnum along a line.

TOPOGRAMS: Lateral. Range: Below base of skull through vertex. 35 mA, 120 kV.

SCAN TYPE:Sequential

NOTES:***Heads ordered With contrast Also perform a WithOut scan. If it is ordered as “Radiologist Decides”, or if it is a younger

patient (Under 40 or especially pediatrics), or if the patient has had a recent CT/MR Head, consult the radiologist. If it is for

simple restaging, possibly only a With contrast scan if the patient has had a Head WithOut scan performed at some point. Consult

the radiologist.***

If With and WithOut do not let patient move between scans, do exactly the same.

If you see abnormality on WithOut, check with Radiologist for possible scan With contrast.

Avoid scanning through lens of eyes.

ALARA – Keep radiation dose As Low As Reasonably Achievable.

HEAD - SEQUENTIAL

Scan
Range / Scan Direction
Scan Type / Respiration / Scan Delay / CARE
DOSE
4D / Quality
Reference
mAs / CARE
kV / Quality
Reference
kV / Detector Configuration
Slices Per Acquisition / Table Feed
(mm) / Scan
Time
Seconds / Cycle
Time
Seconds / SFOV
(cm)
Base of Skull
Through Vertex / Caudocranial
Sequential / Quiet
Respiration / WithOut: 2 Seconds
With: 3 Minutes / ON / 390 / ON / 120 / Detectors: 64 x 0.6 mm
Slices Per Acquisition: 32 / 17 mm / Full
1.0 Sec / 2.5
Seconds / 30
cm
Plane/Gantry Tilt/Reconstruction Angle / SAFIRE
Strength / Slice
Thickness / Interval / Kernal / Window
Width/Level / DFOV
(cm)
RECON – AXIAL SOFT TISSUE / Axial Plane: 25 degrees Caudad to Reid’s Baseline – Superimpose the supraorbital ridge and the inner table of the skull at the foramen magnum / OFF / 5.0 mm / 5.0 mm / H30s
Medium Smooth / Cerebrum
80/35 / FOV just beyond
Patient’s head
RECON – AXIAL BONE / Axial Plane: 25 degrees Caudad to Reid’s Baseline – Superimpose the supraorbital ridge and the inner table of the skull at the foramen magnum / OFF / 5.0 mm / 5.0 mm / H70h
Very Sharp / Osteo
1500/450 / FOV just beyond
Patient’s head
RECON – 3D ONLY
LOAD IN 3D CARD FOR REFORMATS
DO NOT SEND TO PACS / Axial Plane: 25 degrees Caudad to Reid’s Baseline – Superimpose the supraorbital ridge and the inner table of the skull at the foramen magnum
LOAD IN 3D CARD FOR CORONAL & SAGITTAL REFORMATS / OFF / 0.6 mm / 0.3 mm / H30s
Medium Smooth / Cerebrum
80/35 / FOV just beyond
Patient’s head
REFORMAT – CORONAL MPR
Coronals Angled in Plane to Body Part / Coronal Reformats Angled in Plane to Body Part
3D Card (Use 3D Only Recon as Planning Base) / OFF / 5.0 mm / 5.0 mm / H30s
Medium Smooth / Cerebrum
80/35 / FOV just beyond
Patient’s head
REFORMAT – SAGITTAL MPR
Sagittals Angled in Plane to Body Part / Sagittal Reformats Angled in Plane to Body Part
3D Card (Use 3D Only Recon as Planning Base) / OFF / 5.0 mm / 5.0 mm / H30s
Medium Smooth / Cerebrum
80/35 / FOV just beyond
Patient’s head

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*The operator must check the CTDIvol before and after the scan to ensure it is within the allowed dose range. Scans performed outside of the allowed range must be

documented and reviewed by the designated radiologist and/or physicist.

Allowed CTDIvol Dose Ranges:25 mGy – 80 mGy

XR29 Dose Notification Value (CTDIvol):80 mGy

Note: The Diagnostic Reference Dose (CTDIvol) is 75 mGy (with the 16 cm CTDI phantom). The pass/fail limit (ACR and Washington State) is 80 mGy. Most routine head scans on modern scanners have CTDIvol ranges between 40 and 60 mGy.
*The AAPM recommended NEMA XR29 Dose Notification Value for an adult head is 80 mGy. The maximum CTDIvol should match the dose notification value. Exams with CTDIvol values less than the minimum allowed range should not be performed unless approved by a radiologist.

NETWORK:Exam to PACS

12/2017Page 2 of 2