HITACHI Proton Therapy System with Spot Scanning

Transcription

1 Workshop on Hadron Therapy of Cancer 27 th April, Erice, Sicily, Italy HITACHI Proton Therapy System with Spot Scanning Kazuo Hiramoto Energy & Environmental Systems Laboratory, Hitachi, Ltd.

2 Contents Proton Therapy System - Overview and Operating Facilities - Accelerator System - Irradiation System Carbon / Proton Therapy System

3 Workshop on Hadron Therapy of Cancer Apr., 2009, Erice Injector : LINAC 7 MeV Synchrotron : Slow Cycle and Slow Extraction High Energy Transport Irradiation System: Rotating Gantry /Fixed Course Transport HITACHI PBT System Synchrotron Irradiation System: (Rotating Gantry ) Injector: LINAC

4 Workshop on Hadron Therapy of Cancer Apr., 2009, Erice University of Tsukuba - Two Passive Nozzles with Rotating Gantries - Operation Started in 2001 Treatment Room - Over 1000 Patients Treated Rotating 39m Gantries Synchrotron (70-250MeV) Exp. Room

5 M.D. Anderson Cancer Center - Three Rotating Gantry and One Fixed Rooms > Spot Scanning : G3, and Passive : G1, G2 and Fixed - Operation Start : Passive in 06 and Scanning in 08, May - Treatment over 100 Patients/Day Synchrotron (70-250MeV) Gantry Treatment Room Workshop on Hadron Therapy of Cancer Apr., 2009, Erice

6 BM ESD Lattice 7m Extraction to Transport SX R1.4m RF-for Acc. Synchrotron Injection from Linac QD QF RF-for Extraction. Lattice Type Circumference Repetition Inj. Energy Ext. Energy Pulse to Pulse Energy Change Intensity Injection Acceleration Workshop on Hadron Therapy of Cancer Apr., 2009, Erice Strong Focus 23m 2 7 sec 7MeV MeV ppp Variable Spill Length sec Decel. Time

7 Workshop on Hadron Therapy of Cancer Apr., 2009, Erice RF Cavity with FINEMET Core FINEMET Core High complex permeability for Freq. Range 1-10 MHz High Curie temperature 450 mm accelerating gap Simple Operation Non Resonant Freq. Reliable Operation Solid-state Amp. Air Cooling Multiple Power Feeding Impedance matching between RF cavity and RF power source

8 RF Driven Extraction Sextupole magnets (resonance exciter) power f 0 ± f frequency RF Amplifier RF kicker Extracted beam Extraction System of the Synchrotron Workshop on Hadron Therapy of Cancer Apr., 2009, Erice Separatrix is kept constant. amplitude is increased and exceeds the separatrix. Extraction deflector phase space QF ESD x Separatrix x Extraction deflector Magnet Current : Constant Position Time Time Stable Position

9 Workshop on Hadron Therapy of Cancer Apr., 2009, Erice RF Driven Extraction Sextupole magnets (resonance exciter) power f 0 ± f frequency RF Amplifier RF kicker Extracted beam Separatrix is kept constant. amplitude is increased and exceeds the separatrix. Extraction deflector phase space x Separatrix Extraction deflector Variable Spill Timing and Intensity x Extraction System of the Synchrotron Intensity RF On Off On Off Time Time

10 Extraction Spill Control Linac Resonant Exciter Transverse RF for extraction Real Time Feedback Monitor Synchrotron Extracted Rotating Gantry 0.3 sec (Variable) Spill Workshop on Hadron Therapy of Cancer Apr., 2009, Erice Gate Signal

11 Extraction Spill Control Linac Resonant Exciter Transverse RF for extraction Real Time Feedback Monitor Synchrotron Extracted 0.3 sec (Variable) Rotating Gantry Intensity Modulation Signal Spill Workshop on Hadron Therapy of Cancer Apr., 2009, Erice Gate Signal

12 Variable Timing and Op. Length Injection Timing and length of beam extraction and operation can be varied flexibly. - Respiration gating operation - Spot scanning Wait for Extraction Trigger Flat-top Injection, Extraction Acceleration Deceleration Synchrotron Pattern Operaion Cycle Length Synchrotron pattern Inj Ext Inj Acc Dec Acc Wait Wait Workshop on Hadron Therapy of Cancer Apr., 2009, Erice t Respiration Signal Extraction Trigger Extracted Expiratory Inspiratory Ext Dec Wait Wait Variable Repetition Period

13 Workshop on Hadron Therapy of Cancer Apr., 2009, Erice Pulse to Pulse Energy Change Range Modulation for Scanning Cooperation with HEBT Extraction 155MeV 150MeV 145MeV 140MeV 135MeV operation pattern Injection Extracted Signal Pulse to pulse energy change t[sec]

14 Nozzle Configuration Passive Scattering RMW Range Modulation Wheel: RMW Second Scatterer Profile Monitor X-ray Tube 3.2m SOBP Width Control with Gating Dose Monitor Dose Monitor Block Collimator ON Square Collimator Snout Irradiation Head (Iso- Center) Wheel Height Workshop on Hadron Therapy of Cancer Apr., 2009, Erice Circumferential Position

15 Workshop on Hadron Therapy of Cancer Apr., 2009, Erice Nozzle Configuration Passive Scattering Dose Distribution Lateral Range Modulation Wheel Second Scatterer Profile Monitor X-ray Tube 3.2m 25cm Dose Monitor Dose Monitor Square Collimator Snout Block Collimator Irradiation Head (Iso- Center) 16cm 8cm Distal

16 Spot Scanning -Pulse to Pulse Energy Change by Synchrotron - Flat Top and Spill length : Variable for Layers Accel. Variable Length (Max. 5 sec) Injection Energy Change by Synchrotron Layer Proton Decel. Time Discrete Spot Scanning Target Spot Energy Change start layer change position change spot irradiation beam on/off Lateral end? yes Workshop on Hadron Therapy of Cancer Apr., 2009, Erice next layer? yes end

17 Position Stability 15 Planned Spot Positions Deviations between Planned and Measured Spot Positions Y[cm] dy [mm] X[cm] % 50 % Size (air) 5.3mm (1σ) mm dx[mm] 0% Workshop on Hadron Therapy of Cancer Apr., 2009, Erice

18 Measured Dose Distribution Workshop on Hadron Therapy of Cancer Apr., 2009, Erice Distal Distribution with Energy Stacking 12.4g/cm g/cm 2 100% 100% 1.9g/cm g/cm 2 50% 50% 0% Depth [g/cm 2 ] 0% Depth [g/cm 2 ]

19 Carbon/Proton Therapy System Application of technologies used in the proton system to carbon therapy system > Acceleration, Extraction and Scanning BM QF Injection:7MeV/u RF for Extraction Design Parameters Lattice Type Strong Focus Circumference 60m QD 19m Extraction RF Acceleration Configuration of Synchrotron Energy RF Freq. for Extraction Repetition Workshop on Hadron Therapy of Cancer Apr., 2009, Erice P <250MeV C <480MeV/u P : MHz C : MHz 2 7 sec

20 Workshop on Hadron Therapy of Cancer Apr., 2009, Erice RF Acceleration RF Control System RF Cavity Design Parameters Particles P, C Length 1.4 m Magnetic Core Type Frequency FINEMET Non-resonant 1-10 MHz RF Power Amplifier RF Cavity Power Feeding Each Core Accel.Voltage > 2.5 kv RF Amp. Power 6 kw

21 Thank You for Your Attention