CT ORBITS C- (last updated 10/28/2020, last reviewed 10/28/2020)
INDICATION: Trauma, Fracture, Thyroid orbitopathy/Grave's, Foreign body, Fibroosseous disease, Postoperative evaluation (bony).
SERIES
- 3mm Axial bone
- 3mm Axial soft tissue
- 3mm Direct coronal bone
- 2mm Sagittal bone
| | Axial | Direct Coronal* |
|
POSITIONING/MODE
|
supine/helical |
Prone/helical |
|
kV/mA/table rot
|
120 kV/Auto mA/<1 sec |
120 kV/Auto mA/<1 sec |
|
DETECTOR COLLIMATION
|
16 x 0.75mm (S16) 64 x 0.6mm (D64) |
16 x 0.75mm (S16) 64 x 0.6mm (D64) |
|
SLICE THICKNESS
|
3mm |
3mm |
|
PITCH
|
0.45 (S16) 0.7 (D64) |
0.45 (S16) 0.7 (D64) |
|
KERNAL
|
bone (H70h very sharp) soft tissue (H40s medium) |
bone (H70h very sharp) |
|
SFOV
|
<25 cm |
<25cm |
|
COVERAGE
|
hard palate -> frontal sinus |
orbital rim -> sella |
|
ACQUISITION
|
caudocranial |
anterior to posterior |
|
IV CONTRAST
|
none |
none |
|
POSTPROCESSING
|
3mm axial bone and soft tissue 2mm sagittal bone |
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*NOTE: For evaluation of any orbital bony abnormality (fracture, congenital, postoperative evaluation), direct coronals are ideal. If the patient is unable to tolerate positioning for direct coronals, coronal reformats are acceptable.
On direct coronal imaging, the gantry angle should be perpendicular to the infraorbital-meatal line, avoiding metallic dental work.
On axial imaging, the gantry angle should be parallel to the infraorbital-meatal line.