Overview of NIRS Accelerator Activity Koji Noda Research Center for Charged Particle Therapy National Institute of Radiological Sciences Workshop on Hadron Beam Therapy April. 27 09, Erice, Italy Hospital
1. Introduction Contents 2. Tour 3. Development of Technologies at 4. Compact Carbon-Therapy Facility 5. New Treatment-Facility Project
Heavy Ion Medical Accelerator in Chiba 1. Introduction Tokyo Narita international airport National Institute of Radiological Sciences Chiba Prefecture
facility 1. Introduction Ion species: High LET (100keV/μm) charged particles He, C, Ne, Si, Ar Range: 30cm in soft tissue 800MeV/u (Si) Maximum irradiation area: 22cmΦ Dose rate: 5Gy/min Beam direction: horizontal, vertical Size: 7200 m 2 (60 x 120 m) Cost: 320 M US$ (32,600 M JPY) 135 M$ for building 165 M$ for machine (Heavy Ion Medical Accelerator in Chiba)
Progress of treatment number 1. Introduction 800 700 600 500 400 300 200 100 0 advanced medicine. clinical study Treatment Period: 43 wks 1st Term(Apr Aug): 18.5wks 2nd Term(Sept Feb):24.5wks Treatment: 4 days per week 276 241 188 201 159 168 126 83 21 Total: 4504 (Jun 1994 Feb 2009) 684 642 56 549 396 437 411 324 286 495 476 277 110 113 138 166 189 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 333
Statistics of treatment 1. Introduction Eye Lachrymal Digestive duct Lung Liver Rectum Brain Head & Neck Bone & Soft tissue Pancreas Prostate Uterus Tumors Miscellaneous Prostate Lung Eye Head and Rectum Neck Bone/Soft Tissue Uterus Liver Prostate Rectum Bone & Soft Uterus tissue Pancreas CNS Pancreas Liver Uveal Melanoma Lung Skull Base Digestive duct Esophagus Lymph Lachrymal Nodes Lacrimal Gland Brain Head Others & Neck 177 128 101 101 82 52 53 20 12 307 0 100 200 300 400 500 600 700 800 900 0 100 200 300 Patients 452 550 531 491 Total No.: 4,502 762 The histogram shows the number of tumors treated from June 94 to Feb. 09. Total number is 4,502, and treatments of more than 30% are utilized with irradiation gated with respiration.
Typical operation 1. Introduction Mon Tue Wed Thu Hour 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Maintenance or tuning Beam R&D Treatment 20 21 22 23 Treatments: Daytime on weekday Experiment (Phys.&Bio): Night and daytime on weekend. Machine maintenance: Daytime on Monday. Fri Sat Sun Experiment Shutdown Operation time: 8300h/2ring Breakdown ratio:0.6%@ 04
1. Introduction Result of clinical trials Lung Treatment planning GyE T2N0M0 stage IB 28GyE (1 fraction) before 1 year after
1. Introduction Contents 2. Tour 3. Development of Technologies at 4. Compact Carbon-Therapy Facility 5. New Treatment-Facility Project
Linac cascade Ion source tour 2. Tour Synchrotron Irradiation system Treatment room Transport line
Ion source 2. Tour 10GHz-ECR source PIG source 18GHz-ECR source
Linac cascade 2. Tour Alvarez Linac RFQ Linac There are a cascade of linear accelerators consists of RFQ-linac and Alvarez linac. Both are operated with 100MHz RF power. RFQ first accelerates up to 800keV/n, then the Alvarez linac accelerates up to 6MeV/u. They have ability to accelerate ions with charge-mass ratio of 1/7.
The pre-accelerated ions are injected into synchrotrons. There are two synchrotron rings on the lower level and upper level. Circumference is about 130m. Their optical design is normal FODO. The synchrotron can accelerates ions with q/m=1/2 up to 800 MeV/n at the maximum. Synchrotron Injection system 2. Tour Extraction system RF system for acceleration
Beam transport line 2. Tour Vertical beam line Horizontal beam line
Irradiation system 2. Tour Scattering material Dose monitor Wobbling Magnet Ridge Filter Controller Multi Leaf Collimator Range Shifter Cancer Tumor Irradiation area Bolus
Treatment room 2. Tour Horizontal port Vertical port
Positioning patient 2. Tour A patient must be positioned precisely before the treatment by comparing x-ray radiography image to digitally reconstructed radiography image (DRR). Almost cases, it takes about 15 minutes. On the other hand, irradiation takes about 1~2 minutes. Horizontal & vertical beam port
1. Introduction Contents 2. Tour 3. Development of Technologies at 4. Compact Carbon-Therapy Facility 5. New Treatment-Facility Project
R&D for Upgrade of Accelerator 3. R&D 1. For increasing irradiation accuracy Gated Irradiation with Patient s Breathing: RF-KO Slow Extraction Improvement of time structure of extracted beam (Reduction of Spill Ripple) Intensity Modulation Delivering high duty beam 2. For increasing efficiency of treatment and study TSA of Injector Automatic beam-axis alignment Intensity Upgrade Development of Ion Source Development of Electron Cooler 3. Development of key technologies of medical accelerator Step-wise variable energy for Injector Development of non-destructive monitors Development of APF-IH Linac Development of Compact ECR Ion Source Compact Carbon-Therapy Machine Development of Compact Un-tuned RF Cavity
Intensity Upgrade 3. R&D Intensity should be increasing by suppressing space charge effect, which is effective for the compact synchrotron. Laslett tune shift 2 NRr z p ΔQ A y = 2 3 π b( a + b) β γ Q y 1 B f Under several 10 10 c-ions, the vertical tune is spread across a few resonance lines, which decreases beam intensity and lifetime!!
Transverse Gymnastics - Resonance Correction - 3. R&D Resonance correction by using additional sextupoles Before correction Intensity (10 10 ppp) After correction Intensity (10 10 ppp) 0.16 0.12 0.08-0.50-0.25 0 0.25 0.50 0.75 1.0 1.25 1.5 1.75 2.0 2.25 2.5 2.75 3.0 3.5 6.0 0.16 0.12 0.08-0.50-0.25 0 0.25 0.50 0.75 1.0 1.25 1.5 1.75 2.0 2.25 2.5 2.75 3.0 3.5 6.0 0.04 0.04 0.00 0.00 3.05 3.10 3.15 3.20 3.25 3.30 3.35 3.40 Veritcal tune 3.05 3.10 3.15 3.20 3.25 3.30 3.35 3.40 Vertical tune Qx+2Qy=10 Longer lifetime is realized!!
To suppress space-charge effect Longitudinal Gymnastics - Multi-Harmonic Acceleration - ΔQ y Bunch Shape 2 NRr z p = A 2 3 π b( a + b) β γ Q Bunching Factor Large Bf Small ΔQ We can obtain beam intensity more than 2 10 10 carbons in one cycle. y 1 B f 3. R&D
3. R&D Respiration gated irradiation - Irradiation system of coincident with a patient s respiratory motion - Accelerator Interlock system Gated beam extraction system (RF knockout method) Treatment control Watch & record system Gate signal generator Beam monitor Ion beam PSD Respiration waveform Reference Image Compare Positioning Image Planning simulation Positioning area Irradiation room X-ray TV Positioning system using x-ray TV images
3. R&D RF-knockout extraction (1) Diffusion by transverse RF-field Frequency modulation (FM) + Constant separatrix Fast response of beam on/off Easy operation Amplitude modulation (AM)
3. R&D RF-knockout extraction (2) We have developed the RF-KO slow extraction method, since 1994. As a result, we can almost suppress the spill ripple by the dual FM and Separate function methods. NIM-A 522, p.196.
3. R&D RF-knockout extraction (3) 80 Boundary of separatrix Counts (arb. unit) 60 40 20 n=0 n=10 5 AM func. Feedback 0 0.000 0.002 0.004 0.006 0.008 0.010 r Spill Global Spill Control for RF-KO Assuming radial distribution of particle diffused by RF-KO while keeping Reyleigh distribution, The AM function can be optimized so as to keep the extracted intensity constant. A deviation of the optimized AM function from the true one is corrected by the feedback. The right figure shows an experimental result. As a result, we can obtain the constant intensity in the spill.
Global Spill Control and Intensity Modulation 3. R&D f k Function Generators Voltage Controlled Amplifier VCA RF Switch Circulating beam Kicker Electrode V AM RF Amp. AM Function controller Ionization Chanber Scanning Irradiation System Extracted Beam Spill Current Amp 10-6 A/V, 100kHz I T Scanning Magnets Range Shifter I Beam gate Intensity Intensity T
1. Introduction Contents 2. Tour 3. Development of Technologies at 4. Compact Carbon-Therapy Facility 5. New Treatment-Facility Project
4. Compact Facility Specification 1. Ion species: high LET (100keV/μm) charged particle - Carbon 2. Range: Max. 25cm in water 3. Maximum irradiation area: 15cm square 4. Dose rate: 5Gy/min 1.2 10 9 pps (C ions) 5. Irradiation direction : horizontal, vertical 6. Treatment rooms: 3 (H&V, H, V) 7. Irradiation technique: gating & layer stacking irradiation 1. Accelerator systems and Irradiation systems : High reliability, stability, reproducibility, easy operation, easy maintenance and absolute safety 2. The other requirements : - Precise beam delivering - Easy beam tuning in a short time - Accurate dose measurement and control - Fail-safe system
4. Compact Facility Design and R&D for Compact Facility Beam Study Compact RF-cavity Compact Injector RFQ + APF-IH Development Irrad. Tech. Intensity (10 10 ppp) Intensity (10 10 ppp) 0.16 0.12 0.08-0.50-0.25 0 0.25 0.50 0.75 1.0 1.25 1.5 1.75 2.0 2.25 2.5 2.75 3.0 3.5 6.0 0.16 0.12 0.08-0.50-0.25 0 0.25 0.50 0.75 1.0 1.25 1.5 1.75 2.0 2.25 2.5 2.75 3.0 3.5 6.0 0.04 0.04 0.00 0.00 3.05 3.10 3.15 3.20 3.25 3.30 3.35 3.40 3.05 3.10 3.15 3.20 3.25 3.30 3.35 3.40 Veritcal tune Vertical tune High-Precision MLC
4. Compact Facility Gunma University Heavy-Ion Medical Center Treatment Room Synchrotron 10Ghz-ECR Injector Linac APF-IH
4. Compact Facility Gunma University Heavy-Ion Medical Center
1. Introduction Contents 2. Tour 3. Development of Technologies at 4. Compact Carbon-Therapy Facility 5. New Treatment-Facility Project
Motivation of New Treatment Facility 5. New Project (a) (b) 840cc 69cc Large changing target shape and size We should modify a treatment planning corresponding to change of target during treatment, Adaptive Cancer Treatment
Present Method 5. New Project Broad Beam Method with Wobbler and Scatterer Dose distribution is independent of beam quality Easy dose management Low beam-utilization efficiency Extra-dose is given on normal tissue when irregular shape Require Bolus and patient collimator
3D Scanning Method 5. New Project Adaptive Therapy by 3D Scanning 1) Beam utilization efficiency 100% 2) Irradiation on irregular shape target 3) No bolus & collimator 1) Depend directly on beam quality 2) Not easy dose management 3) Sensitive to organ motion Scanner Monitor Range Shifter Beam Dose distribution of pencil beam
3D organ motion with breathing 5. New Project
-40-20 NIRS Simulation of moving tumor irradiation 100 120 140 160 180 200 0 20 40 Non-gating Example: Φ40mm spherical target Motion:7mm in gate -40 Gating -20 100 120 140 160 180 200 0 20 40 Moving Tumor Irradiation Fast Scanning is the key technology for completing rescanning within tolerable time. ( πt / 3, φ ) s( t) = 1.7 31.3 cos 2s 4-40 -20 100 120 140 160 180 200 0 20 40 5. New Project Gating with rescanning (8 times) In order to avoid hot/cold spot due to target motion, we decided to employ gating method with rescanning. 0 0.1 0.2 0.3 0.4 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.1
Fast scanning for moving target 5. New Project In order to realize the rescanning with gating within acceptable irradiation time, we have studied following strategy. 1. Treatment planning for fast scanning 5 2. Modification of acc. operation 2 3. Fast scanning magnet 10 100-times speed up of irradiation time
5. New Project (1) Planning for fast scanning Optimization including the contribution of extra dose in raster scanning 50 0.5 0.4 0.3 0.2 0.1 0.0 0 50 100 150 200 0.0 0.1 0.2 0.3 0.4 Without U i 0.5 Ui Beam intensity y (mm) 0-50 0 50 Fast scanning with beam of high intensity EDR cause dose distortion -50-50 0 x (mm) 50 f Cost function : f(w) ( ) o w = Q D ( w) i T P max 2 u min 2 [ ] [ ( )] max biol, i + U i DP + Q + [ ( ) + ] + P DP U i Dbiol, i w + + QO Dbiol, i w U i DO i O 2 + Predict EDR 0.5 0.4 0.3 0.2 0.1 0.0 0 50 100 150 200 0.0 With U i 0.1 0.2 0.3 0.4 0.5-50 Extra dose in raster scanning (EDR) : U i 0 50
(2) Extended FT in Synchrotron 5. New Project SMx Fluorescent screen SMy Beam Syn. BM 1. Treatment planning for fast scanning 5 2. Modification of acc. operation 2 3. Fast scanning magnet 10 Since 2 10 10 c-ions is enough high to complete single-fraction, we have employed the extended FT to save the dead time of synchrotron operation. plan
5. New Project (3) Fast Scanning Magnet 100mm/ms in H 50mm/ms in V Scanning Magnet Pos. Moni. Dose Moni Range Shifter Since 29 December 2008
Fast 3D-Scanning Experiment 5. New Project (1)+(2) Total time: Scanning time: Range-shifter time: 76 s 64 s 12 s (1)+(2)+(3) Total time: 18.5 s Scanning time: 6. 5 s Range-shifter time:12 s
5. New Project 11-steps Energy Operation Toward Variable-Energy 430 MeV Flattop 140 MeV Accel 加速 Decel 減速 入射 Inj Operation Pattern Flattop
5. New Project 11-steps Energy Operation C 6+, 290 MeV/n 11-steps Beam Extraction Operation Pattern (SX) Stored Beam Beam Spill
Phase-Controlled Raster Scanning Average position of target in each slice is to be Zero one slice with rescanning in one gate y 1st scan 5. New Project respiration signal 6 Gate ON time 3rd scan 2nd scan x averaged distribution displacement (mm) 4 2 0-2 Δr 1 Δr 2 Δr 3 respiration gate -4 1st 2nd 3rd 4th 5th 6th time 1st scan 0.5 1.0 1.5 2.0 2.5 time (s) beam current time z slice No. n n+1 n+2 n+3 scanning trajectory This method needs intensity modulation.
5. New Project PCR method ~ experiment Fabrication of moving phantom XY moving stage Wedge for range variation It is possible to operate arbitrary waveform. Screen+CCD system is set on the stage. Specification X and Y direction : ±20mm Range direction : ±17mm (WEL) Max. speed: 40 mm/s
5. New Project PCR method ~ experiment Experimental result Simulation result -100-50 0 50 100 100 100 200 300 400 500 600 0 0 0.024 100 200 300 2560 5120 7680 10240 50 0 0.047 0.071 0.095 Non-gating Non-rescanning 400 12800 15360-50 0.119 500 16384 0.143-100 0.152-100 -50 0 50 100 100 0 100 200 300 400 500 600 0 0.024 100 200 300 2560 5120 7680 10240 50 0 0.047 0.071 0.095 Non-gating With rescanning (PCR) 400 500 12800 15360 16384-50 -100 In this stage, we only tested 2D uniform scanning without gating. Next step is 3D scanning test including non-periodic irregular motion! 0.119 0.143 0.152
5. New Project New Treatment Facility: Specification 1. Ion species: 12 C, 16 O ( 11 C, 15 O) 2. Irradiation method: PCR with Gating 3. Range: > 25cm in water 4. Maximum irradiation area: 22cm square for Fixed Port 15cm square for Gantry 5. Delivered Intensity: 10 7-10 9 pps (C ions) 6. Treatment rooms: 2 (H&V), Rotating gantry
New Treatment Facility (1) 5. New Project 3D Scanning with Gating (H&V): 2 rooms Rotating Gantry : 1 room Research Building for Charged Particle Therapy building Hospital New treatment facility Rotating Gantry Wall RGF QM PRN1 SMx SMy PRN2 RSF 3D Scanning 9.0 m Monitors 0 1 2m Iso-center
New Treatment Facility (2) 5. New Project Ground-Breaking Ceremony Construction 19 Feb, 09 6 Feb, 09
New Treatment Facility (3) 5. New Project The construction of the new treatment facility will be completed at March 2010. New facility building Thanks for your attention!!