HITACHI Proton Therapy System with Spot...

HITACHI Proton Therapy System with Spot Scanning

Kazuo Hiramoto

Energy & Environmental Systems Laboratory,Hitachi, Ltd.

“Workshop on Hadron Beam Therapy of Cancer”27th April, Erice, Sicily, Italy

・ Proton Therapy System・ Proton Therapy System

- Accelerator System - Accelerator System

- Irradiation System- Irradiation System

Contents

・ Carbon / Proton Therapy System・ Carbon / Proton Therapy System

- Overview and Operating Facilities- Overview and Operating Facilities

“Workshop on Hadron Therapy of Cancer” Apr., 2009, Erice HITACHI, Ltd.

Synchrotron

Injector:LINAC

Beam Transport

Irradiation System: (RotatingGantry )

Injector : LINAC 7 MeVSynchrotron : Slow Cycle and Slow ExtractionHigh Energy Beam TransportIrradiation System: Rotating Gantry /Fixed Course

HITACHI PBT System


39m

TreatmentRoom

Exp. Room

University of Tsukuba

Synchrotron (70-250MeV)

- Over 1000 Patients Treated RotatingGantries

- Operation Started in 2001

- Two Passive Nozzles with Rotating Gantries


M.D. Anderson Cancer Center

Synchrotron (70-250MeV)

- Treatment over 100 Patients/Day

> Spot Scanning : G3, and Passive ： G1, G2 and Fixed

- Operation Start : Passive in ‘06 and Scanning in ‘08, May

- Three Rotating Gantry and One Fixed Beam Rooms

Gantry Treatment Room


Synchrotron

7m

R1.4m

Injectionfrom Linac

Extraction to Beam Transport

BM

ESD

SX

QF

QDRF-forAcc.

Lattice

RF-forExtraction.

2 – 7 sec

Strong Focus

70-250MeV

Repetition

Lattice Type

Ext. Beam Energy

Circumference 23m

TimeInjection

AccelerationDecel.

0.5 – 5 secVariable Spill LengthPulse

to Pulse

Energy Change

1011 ｐｐｐIntensity

Inj. Beam Energy 7MeV


450 mm

Multiple Power FeedingImpedance matching betweenRF cavity and RF power source

accelerating gap FINEMET Core•High complex permeability for Freq. Range 1-10 MHz

•High Curie temperature

Simple Operation• Non Resonant

Freq.Reliable Operation•Solid-state Amp. •Air Cooling

RF Cavity with FINEMET Core


RF Driven Beam Extraction

Separatrix

Separatrix is kept constant. Beam amplitude is increased and exceeds the separatrix.

x

x’Beam

Sextupole magnets(resonance exciter)

Extracted beam

Extraction deflector

phasespace

RF kicker

RF Amplifier

pow

er

frequency

f0±⊿f


Magnet Current : Constant

Beam Position Time

Stable Beam Position

Time

QFESD

Extraction System of theSynchrotron


RF Driven Beam Extraction

Separatrix

Separatrix is kept constant. Beam amplitude is increased and exceeds the separatrix.

x

x’Beam

Sextupole magnets(resonance exciter)

Extracted beam


phasespace

RF kicker

RF Amplifier

pow

er

frequency

f0±⊿f


Extraction System of theSynchrotron TimeRF

Time

Variable Spill Timing and IntensityBeam

Intensity

On Off On Off


Extraction Spill Control

Gate Signal

Spill

0.3 sec (Variable)

Beam Extracted

Beam Monitor

RotatingGantry

Synchrotron

ResonantExciter

Linac

Real Time Feedback

Transverse RFfor extraction


Extraction Spill Control

Beam Extracted

Beam Monitor

RotatingGantry

Synchrotron

ResonantExciter

Linac

Real Time Feedback

Transverse RFfor extraction

Gate Signal

Intensity Modulation Signal

Spill

0.3 sec (Variable)


ExtDec

InjAcc

ExtDec

Wait Wait

InjAcc

Wait Wait

Synchrotron pattern Variable Repetition Period

tInjection,Acceleration Deceleration

Extraction

Flat-top

Injection Wait for ExtractionTrigger

Inspiratory

Expiratory

ExtractionTrigger

RespirationSignal

SynchrotronPatternExtracted

Beam

・Timing and length of beam extraction and operationcan be varied flexibly. - Respiration gating operation- Spot scanning

Operaion Cycle Length

Variable Timing and Op. Length


Pulse to Pulse Energy Change

Range Modulation for ScanningCooperation with HEBT

0 4 8 12 16 20t[sec]

155MeV 150MeV 145MeV 140MeV 135MeV

Pulse to pulse energy change

operationpattern

Extraction

InjectionExtracted

BeamSignal


Passive Scattering

Dose Monitor

X-ray Tube

Block Collimator

Square Collimator

Snout

Irradiation Head

(Iso- Center)

Beam

Dose Monitor

Profile MonitorRange Modulation Wheel: RMW

Second Scatterer

3.2m

Nozzle Configuration

Whe

el

Hei

ght

Beam ON

Circumferential Position

RMW

SOBP Width Control with Gating


Passive Scattering

Lateral

25cm

Distal

16cm8cm

Dose Monitor

X-ray Tube

Block Collimator

Square Collimator

Snout

Irradiation Head

(Iso- Center)

Beam

Dose Monitor

Profile MonitorRange Modulation

Wheel

Second Scatterer

3.2m

Nozzle Configuration Dose Distribution


Spot Scanning-Pulse to Pulse Energy Change by Synchrotron

Energy Change by Synchrotron Target

SpotLayer

Proton Beam

position change

spot irradiationbeam on/off

layerchange

Lateral end?

next layer?

start

end

yes

yes

Discrete SpotScanning

- Flat Top and Spill length : Variable for Layers

TimeInjection

Accel. Decel. Energy ChangeVariable Length(Max. 5 sec)


Beam Position Stability

0 15-15 X[cm]

Y[cm]0

15

-15

0 1.0-1.0dX[mm]

dY [mm]0

1.0

-1.01.0mm

0%

50%

100%

0 20-20

Beam Size (air)

Planned Spot Positions

5.3mm(1σ)

Deviations between Planned and Measured

Spot Positions


Measured Dose Distribution

10 20 300Depth [g/cm2]

20.0g/cm2

30.6g/cm2

0%

50%

100%

Distal Distribution with Energy Stacking

0%

50%

100%

1.9g/cm2

12.4g/cm2

10 20 300Depth [g/cm2]


Carbon/Proton Therapy System

QF

QD

19m

Injection：７MeV/u

Extraction

BM

RF Acceleration

RF for Extraction

> Acceleration, Extraction and Beam Scanning

・ Application of technologies used in the proton systemto carbon therapy system

Configuration of Synchrotron

Strong Focus

P


RF Acceleration

RF Cavity

RF Power Amplifier

RF Control SystemRF Cavity Design Parameters

Accel.Voltage > 2.5 kV

Magnetic Core FINEMET

Power Feeding Each Core

Length 1.4 m

RF Amp. Power 6 kW

Particles P, C

Frequency 1-10 MHz

Type Non-resonant

Thank You for Your Attention

HITACHI Proton Therapy System with Spot...

Documents

Transcript of HITACHI Proton Therapy System with Spot...