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Traditional Invivo Diodes solution
InVivo 3D Patient Dose Verification System
Lin Xu, Medical Physicist IBA Dosimetry, SEACOM Chiangmai 2012
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Protect, Enhance, and Save Lives
However…
Alternative solution: EPID based Invivo solutions
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Time consuming for the diode device positionning before the treatment
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Operator dependant
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Point doses like Dmax or Prescription dose
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Doesn’t take account of the patient anatomy
Protect, Enhance, and Save Lives
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Protect, Enhance, and Save Lives
EPIgray: one solution – two integrated products
InVivo Manager (IVM)
EPIgray
Web-based dashboard (access from anywhere
in hospital network)
Expert application (dedicated workstation)
EPIgray: True workflow efficiency for patient safety
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Get the Plan
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Protect, Enhance, and Save Lives
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Protect, Enhance, and Save Lives
CT, RTStruct, RTPlan, RTDose
Get the Images
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EPID images from Linac console or Database
EPIgray calculates automatically at import
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immediate display of results and expert analysis mode
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reconstructed dose versus reference, at points of
interest
Get results and alerts at your convenience
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How it works? The basic physics
Clinical Examples: First fraction
Analyze patient position with Skin
Projection
P. François, Ph. Boissard, L. Berger and A. Mazal, «In Vivo Dose Verification From Back Projection Of A Transit Dose
Measurement On the Central Axis Of Photon Beams», Paper accepted for publication the 10th of June 2010 at «Physica
Medica»
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Protect, Enhance, and Save Lives
Prescribed / Actual Doses to Reference
Points
Protect, Enhance, and Save Lives
Several fraction later: a patient positioning error
detected (External movement)
EPIGRAY EXPERT SYSTEM:
A patient positioning issue?
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Or errors combine with collimator rotation
A combined Patient position issue with forgotten collimator rotation ?
EPIGRAY EXPERT SYSTEM:
Color coded Alerts
Protect, Enhance, and Save Lives
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Protect, Enhance, and Save Lives
Lung Study with CBCT (Internal movements)
CT Scanner
Clinical results at Institut Curie
Cone Beam CT before treatment session
Field OAG :
Field OAG :
Equivalent path: 26,5cm
Equivalent path: 31,7cm
Depid / Declipse : 0,886
Protect, Enhance, and Save Lives
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Depid / Declipse : 0,983
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Protect, Enhance, and Save Lives
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EPIGray Benefits Summary
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Invivo 3D patient absolute dose verification system with EPID
transit/exit measurements, no perturbance to the beam.
Not only detect the patient dose error but also the patient
internal/external movement errors.
Easy to use, less setup/calibration time, therapist can handle it.
Instant result displaying in seconds instead of long calculation time.
Unique InVivo Manager
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Dicom server for fast data transfer from TPS/R&V
Instant email alert
Remote access through web browser
Result statistics for each LINAC or each tumor locations
Protect, Enhance, and Save Lives
Thank you
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