SLIDE 1
Initial Results from Multiple Irradiations
- f an Anthropomorphic Spine Phantom
lung lung heart
Spine phantom
PTV bone spinal cord esophagus
Initial Results from Multiple Irradiations of an Anthropomorphic - - PowerPoint PPT Presentation
Initial Results from Multiple Irradiations of an Anthropomorphic - - PowerPoint PPT Presentation
Initial Results from Multiple Irradiations of an Anthropomorphic Spine Phantom Andrea Molineu, Nadia Hernandez, Paola Alvarez, David Followill, Geoffrey Ibbott Spine phantom heart esophagus lung lung PTV spinal bone cord Treatment Plan
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SLIDE 3
Treatment Plan
- 6 Gy to at least 90% of PTV
- Min PTV dose at least 5.25 Gy
2.78 1000 cc Whole Lung 9.75 8.63 <10 cc Skin 6.00 4.46 <5 cc Esophagus 8.25 6.00 <15 cc Heart 5.25 3.75 2.63 <0.35 cc <1.2 cc Spinal Cord Max Point Dose (Gy) Volume Max (Gy) Volume Normal structure
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Representative Treatment Plan
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Criteria
- TLD
±7%
- Film (axial and sagittal
planes) 85% meet 5%/3mm
- Plan DVH
must comply with protocol
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Good Agreement
Plan Measurement
PTV Cord/bone OAR
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Good Agreement
Gamma Measurement 100% passing
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Poor Agreement
PTV Cord/bone OAR
Measurement Plan
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Poor Agreement
Gamma Measurement 100% passing 26% passing
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Overall results
- 41 irradiations at 35 institutions
- 17 irradiations failed
- 1 failed TLD criteria only
- 8 failed gamma criteria only
- 8 failed both TLD and gamma
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All Results
42 - 99 22 - 100 0.67 - 1.51 0.88 - 1.15 range 14.6 16.4 0.17 0.05 std dev 86 85 1.02 0.99 mean Sagittal Gamma Axial Gamma Heart PTV
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Passing Results
85 - 99 85 - 100 0.67 - 1.18 0.93 - 1.03 range 5.1 4.6 0.12 0.03 std dev 94 94 1.02 0.99 mean Sagittal Gamma Axial Gamma Heart PTV
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Results by Machine
8 8 1 24 41 total 2 3 8 13 Varian 1 1 2 TomoTherapy 1 1 2 Siemens 2 1 10 13 Novalis 2 2 2 6 Elekta 2 1 2 5 CyberKnife
Dose and Gamma Gamma TLD Dose Criteria Failed Passes Irradiations
Machine Manufacturer
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Results by TPS
8 8 1 24 41
total
1 1 1 3
superposition XiO
1 1 3 5
convolution
Pinnacle
1 7 8
pencil beam
1 1 2 4
Monte Carlo iPlan
1 1 2
superposition Hi-Art
1 1 2
pencil beam
1 4 7 12
AAA Eclipse
2 1 1 4
raytracing
1 1
Monte Carlo CyberKnife Dose and Gamma Gamma TLD Dose Criteria Failed Passes Irradiations
Algorithm TPS
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Results by Algorithm
8 8 1 24 41
total
2 1 1 4
raytracing
2 8 10
pencil beam
1 1 3 5
Monte Carlo
2 3 5 10
superposition/ convolution
1 4 7 12
AAA Dose and Gamma Gamma Dose Criteria Failed Passes Irradiations Algorithm
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Conclusions
- Challenging credentialing
process
- Treatment couch should be
considered in these treatments
- Cannot make generalizations
with regard to machine, TPS,
- r algorithm
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