Cyberknife CT Scan Protocol
General
1. Patient set up should be reproducible and comfortable with arms down by sides.
2. Space and punctuation (dashes, slashes, commas, parenthesis, etc.) may not be used in the patient ID.
3. No more than 512 slices per scan.
4. No gantry tilt is allowed.
5. FOV, table height and slice thickness must remain constant throughout the entire scan.
6. Patients scanned prone must be flagged ‘supine’ to be accepted by CyberKnife.
7. Soft tissue patients receiving IV contrast will be flagged and require two separate scan, unless otherwise stated.
8. Liver studies are to be done in three-phase contrast?
Intracranial Cases
1. Custom headrest with memory foam and mask must be used for immobilization.
2. Patient should be centered left/right in the FOV.
3. Contiguous ~1.0 mm. slice thickness.
4. The superior border should extend ~ 1 cm beyond top of head, or the top of the cast board.
5. The anterior border should extend ~ 1 cm beyond the tip of the nose.
6. The inferior border should include the entire chin (mandible and skin).
7. The posterior border should include the headrest.
Extracranial Cases
1. A VacLok bag should be used for immobilization with a custom headrest with foam, for lesions above carina, a mask should be made.
2. Contiguous 1.5 mm slice thickness.
3. As many slices as possible without exceeding 512 slices.
4. Slices should be centered on the fiducials or tumour target.
5. FOV should include the entire patient circumferences, except for very large patients (it is preferable to have large patients’ scan cut off posteriorly rather than anteriorly).
6. Mandible should be included in lung scans, particularly upper and middle lung tumors.
7. Fast spiral.
8. Breathing instructions must be reviewed with the patient prior to scanning, and are available online as well.
Revised 10/13/10