Immoblization workshop less is more and why

1. © Vision RT 2018
IMMOBILIZATION
WITH SGRT
0004-0019 Issue 1.6 05-Feb-2018

2. © Vision RT 2018
OVERVIEW
Immobilization that supports SGRT use
• Why is immobilization so important for optimal
SGRT use?
• What do we mean by less is more?
• How to use vac-lok bags that produce rigidity and
optimal tracking for SGRT.
• Extremities
• How to make an open face mask that produces
rigidity and optimal tracking for SGRT.
• Live demo
• CIVCO new head immobilization debut

3. © Vision RT 2018
IMMOBILIZATION WITHOUT SGRT
Previous methods of immobilization
• Full face mask
• Wrap extremities in vac lock bags
• Vac-lok for lung or SBRT cases
• Build up sides of bag to form to patient
What happens if we try to use these immobilization techniques with
SGRT?
• We aren’t able to see the patient’s skin surface to use SGRT and draw
and optimal ROI.

4. © Vision RT 2018
LESS IS MORE

5. © Vision RT 2018
LESS IS MORE… AND WHY
What do we mean “Less is More”?

6. © Vision RT 2018
LESS IS MORE… AND WHY
What do we mean “Less is More”?
By limiting what is blocking the camera’s view, we have More to work with
when choosing an ROI!

7. © Vision RT 2018
LESS IS MORE

8. © Vision RT 2018
REGIONS OF INTEREST
• During treatment capture or
monitoring the surface is
automatically registered to the
reference ROI to determine
patient misalignment.
• Although the entire reference
surface is displayed, only the
selected ROI is used during
the registration.
• If the cameras can’t see the
ROI because its blocked or
covered by immobilization,
then we can’t perform an
accurate match!

9. © Vision RT 2018
WHAT HAPPENS WHEN WE CAN’T SEE OUR ROI?
Insufficient surface overlap
Jumpy Deltas ROI propagation warning message

10. © Vision RT 2018
ROI RULES
Proper immobilization is crucial to meeting our four ROI rules!
1. Draw the ROI to include the isocenter (if possible) and
surrounding area
2. Ensure the ROI extends laterally to the patient’s midline to
ensure delta readout if camera is occluded
3. Include a stable surface that includes patient topography
4. Ensure to ONLY include the patient’s skin surface in the ROI
(excluding anything not part of the patient ex. Immobilization
device, gown, patient clothing, table, etc.)

11. © Vision RT 2018
VAC-LOK BAGS AND SGRT
Vac-Loks
• When making a vac-lok or cushion, try not to extend the
device over an area where a ROI will be placed
• As discussed in our four ROI rules, we would like the ROI to
extend laterally to the patient’s midline
• So for an extremity example - Instead of wrapping patient’s
leg, only come up to midline.
– Include anchor points for reproducibility
» Foot stop or joint area

12. © Vision RT 2018
EXTREMITIES WITH SGRT

13. © Vision RT 2018
EXTREMITY ROI
Include:
• Surrounding tissue of isocenter
• Patient topography to ensure ROI
does not look cylindrical (ex.
Joint)
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14. © Vision RT 2018
EXTREMITY ROI
Do NOT include:
• Clothing or
immobilization
• Cylindrical shape
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15. © Vision RT 2018
OPEN FACE MASKS
Published paper from UCSD published in Neurosurgery showing that
we can give the same clinical outcomes as more invasive approaches,
but with:
• Significantly improved patient comfort and
• Fast treatment times (about 20 minutes)
• Open mask to track the actual patient during all couch angles
We have VisionRT Compatible masks including 1
• CIVCO
• Bionix
• Macromedics
• Orfit
• Qfix

16. © Vision RT 2018
TIPS FOR SUCCESS
SRS/Brain
4-5cm superior to the eyebrow Rigid chin
Lateral surface!

17. © Vision RT 2018
SRS BRAIN – ROI EXAMPLE
Include:
• Eye brows, nose, forehead, cheeks
• Laterally: Outer canthus to the
anterior of the tragus
• Ensure there is a small gap
between the edge of the mask
and the edge of the ROI
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18. © Vision RT 2018
SRS BRAIN – ROI EXAMPLE
Do NOT include:
• Mouth
• Mask
• Hair (side burns, bangs,
etc...)
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19. © Vision RT 2018
WHY IS THE LATERAL ASPECT OF AN SRS ROI SO
IMPORTANT?

20. © Vision RT 2018
DEMO
• CIVCO: Type S Thermoplastic ClearVision2 Open face masks

21. © Vision RT 2018
CIVCO TO INTRODUCE NEW MASK

22. © Vision RT 2018
CIVCO TO INTRODUCE NEW MASK
Features
• Mid-line Thermoplastic
• Simple Therm Attach
• Pitch correction
• Headrest customization
• Attach to existing baseplates
or extensions
• Compatible with precise bite

23. © Vision RT 2018
CIVCO TO INTRODUCE NEW MASK
0º -5º+5º
Pitch Correction
• +/-5deg, index markings
• CT sim, change angle for set-up preference – beam angle, neck
curvature, patient comfort
• Treatment set-up correction

24. © Vision RT 2018
CIVCO TO INTRODUCE NEW MASK
Pitch Correction
• Simple lock/un-lock
• Free-float adjustment

25. © Vision RT 2018
CIVCO TO INTRODUCE NEW MASK
Clip Docking
• New and innovative!
• No pins to lock & un-lock in series
• Quick attachment & removal
• Safe design
• Positive clinical feedback

26. © Vision RT 2018
VALIDATE WITH VISION RT

27. © Vision RT 2018
KNOWING WHERE YOUR PATIENT IS
MAKES ALL THE DIFFERENCE