Energistyrning 4 270 degree bending magnet S/H e - PRF * PRF Power amplifier Pulse transformer * ADC Computer program DAC High voltage Gun BBd/2008 1
Accelerator wave-guide Energistyrning 5 Gun Comparator Control Target Updown counter PROM DAC Ionisation chamber In modulator Thyratron Thyratron driver BBd/2008 2
Energy switch BBd/2008 3
BBd/2008 4
e - 90 Magnet Böjmagneter E 0 + E 270 E 0 E 0, E 0 ± E B N S E 0 - E E 0 E 0 + E e - E 0 - E Magnet Slalom Magnet E 0 + E e - E 0 - E Magnet Slits Target BBd/2008 5
90 -böjmagnet E 0, e - E 0 ± E B E 0 - E E 0 E 0 + E e - e - E 0 B E 0 B BBd/2008 6
http://www.khulsey.com/oncordet.html Siemens 270 -böjmagnet BBd/2008 7
Slalom-böjkammare BBd/2008 8
Slalom-böjmagnet BBd/2008 9
Vad finns i strålhuvudet? BBd/2008 10
Strålhuvud; fotoner Bending magnet Accelerator wave-guide e - Bellow photons e - Bending chamber Electron window Primary collimator Target Primary scatter foil Filter Secondary scatter foils Ionisation chamber Wedge Mirror Lamp MLC MLC Collimators BBd/2008 11
Strålhuvud; elektroner Bending magnet Bending chamber Accelerator wave-guide e - Bellow photons e - Electron window Primary collimator Target Primary scatter foil Secondary scatter foils Filter Ionisation chamber Mirror Wedge Sänkt elektronström med en faktor ca 100 Lamp MLC MLC Collimators BBd/2008 Electron 12 applicator
Dålig effektivitet i target e - 0.5MV Target N Energispektrum Fotoner Elektroner γ 1MV 2MV E 5MV 8MV BBd/2008 13
Utjämningsfilter Target Avstånd Profiler på olika djup i patienten N N Avstånd i vatten Energi Energi BBd/2008 14
Filterkarusell BBd/2008 15
Scattering foil 1 Dubbla spridningsfolier Scattering foil 2 Treatment plane BBd/2008 16
Elektronapplikatorer Single scattering foil Diaphragms Double scattering foils a) b) BBd/2008 17
Skannande elektronstråle Scanning magnets Collimators BBd/2008 18
Jonisationskammare BBd/2008 19
Zero Dosimetrisystem - + Reference v Comparator Mono stable Counter v Figure 137.ppt Output voltage Digital comparator Set absorb Time dose register BBd/2008 20 Terminate radiation
Dosimetrisystem 300V Ionisation chamber 300V Monitoring In software Integrator and tracker Integrator and tracker Dummy dose-rate generator from software Control Status latches Control Dummy dose-rate generator from software Dose-rate Dose 1 and timer 1 in software Dose difference in software Dose 2 and timer 2 in software Dose-rate Excess dose-rate Air temperature and air Pressure compensation Excess dose-rate BBd/2008 21
Elektroner träffar target Primärkollimator Primärkollimator A B C D A B C D BBd/2008 22
Elektronbehandling N E Ytan av objektet Vid bendingmagneten Vid 2cm djup BBd/2008 23
Primärkollimering BBd/2008 24
Sekundärkollimering BBd/2008 25
Asymmetrisk kollimering och block Isocenter BBd/2008 26
Flerbladskollimator (MLC) BBd/2008 27
Flerbladskollimator (MLC) Monitor Control To leaf motors Video Target Light projector Mirror Video camera Mylar mirror Reflector Leaf Semi permeable mirror Mirror Patient plane Leaf motors BBd/2008 28
Flerbladskollimator (MLC) Monitor Flexible cables Multi- Frame plexer grabber Demultiplexer Video camera Leaf motors BBd/2008 29
Kil Physical Wedge Flying Wedge Dynamisk Wedge BBd/2008 30
Kil BBd/2008 31
Kompensatorer BBd/2008 32
Bildgivande system (EPID), film 6MV Rtg 25cm Luft Vatten Ben 100% 30% 25% BBd/2008 33
Jonisationskammare BBd/2008 34
Epid med fosforskärm och kamera BBd/2008 35
Indirekt detektering Elekta iview EPID Cablon Theraview Siemens Beamview Eliav PORTpro Direkt detektering BBd/2008 36
Panel från PerkinElmer Rtg - - Aluminium Luftgap Koppar Grafit Lanex Fast TM (Gd 2 O 2 S:Tb) Attenuator Fotodioder, amorft kisel BBd/2008 37 Jöns Jacob Berzelius
CT-system på acceleratorn BBd/2008 38
Elektas XVI-system BBd/2008 39
Intensitets Modulerad Radioterapi (IMRT) www.raysearchlabs.com/contentpage 159.aspx... www.nd.edu/~hliu/schoolpage/medical.html BBd/2008 40
Tomotherapy BBd/2008 41
BBd/2008 42
GammaKnife och CyberKnife www.gammaknifestockholm.com BBd/2008 43 www.aapm.org/.../singletopic/icyberknife.asp
Enhanced dielectric-wall linear accelerator 09/22/1998 Document Type and Number: United States Patent 5811944 Link to this page: http://www.freepatentsonline.com/5811944.html Abstract: A dielectric-wall linear accelerator is enhanced by a high-voltage, fast e-time switch that includes a pair of electrodes between which are laminated alternating layers of isolated conductors and insulators. A high voltage is placed between the electrodes sufficient to stress the voltage breakdown of the insulator on command. A light trigger, such as a laser, is focused along at least one line along the edge surface of the laminated alternating layers of isolated conductors and insulators extending between the electrodes. The laser is energized to initiate a surface breakdown by a fluence of photons, thus causing the electrical switch to close very promptly. Such insulators and lasers are incorporated in a dielectric wall linear accelerator with Blumlein modules, and phasing is controlled by adjusting the length of fiber optic cables that carry the laser light to the insulator surface. BBd/2008 44
Dielectric Wall Accelerator Ett pulsat accelerationsfält bildas i asymmetriska Blumlein Korta pulser <10 ns och hög ström >1 ka. Användning av höggradientisolatorer. Mål: 250 MV på 2.5 m. www.aapm.org/.../singletopic/innovative.asp BBd/2008 45
Vad är en transmissionsledning? i(z,t) koaxialkabel i(z+δz,t) ε Δz 0 www.sm.luth.se/~urban/master/theory/4.html Ekvivalent schema BBd/2008 46
Single line Högspänningskälla (V 0 ) Hur ser spänningen ut längs kabeln? l 2R 2R Om den karakteristiska impedansen Z 0 = R Slås till vid t=0 Spänning över kabeln V 0 V 0 V 0 V 0 t=0 l längd t=l/2ν p l t=l/2ν p l t=3l/2ν p l Utspänning V 0 /2 2l/ν p tid BBd/2008 47
Blumlein line l Högspänningskälla (V 0 ) Induktans ε ε ε ε Öppnar vid V 0 R V 0 Utspänning l/ν p 3l/ν p tid BBd/2008 48
Stackade Blumlein line 0 ε l l/ν p <t<3l/ν p V 0 0 V 0 0 ε ε ε ε 0 = 0 V 0 0 ε Kortslut vid t=0 t<0 t>3l/ν p BBd/2008 49
Symmetrisk Blumlein - t 1 t + - 2 t + - 3 t + - - 4 t + - - 5 + - ε ε ε ε ε ε ε ε ε ε V + - + - t 1 t 2 t 3 t 4 t 5 BBd/2008 50 t
Höggradientisolator (HGI) Överslag (elektriskt fält) 1000kV/cm HGI Motsvarande isolator 10 4 ns Pulsbredd BBd/2008 51
BBd/2008 52
Gitterstuktur Silicon Carbide (SiC) crystals BBd/2008 53
Silicon Carbide (SiC) crystals BBd/2008 /Caporaso et. 54 al.
Olika längd på ljusledarna => olika tillslagstider BBd/2008 /Caporaso et. 55 al.
BBd/2008 56
Fotoledande switch http://www.iee-cambridge.org.uk/arc/seminar04/slides/teraview.pdf http://www.spi.uni-hannover.de/2001/presentations/lee.pdf BBd/2008 57
Vakuum ytöverslag-switching di/dt >10 13 A/s 200kV Vakuum Laser https://www.llnl.gov/str/march07/felton.html Fotoledare eller elektronstråle inducerad solid-state switchar. Gaser under högt tryck och flytande dielektriska switchar BBd/2008 58
https:/.../2006/sf-06-04-02p.html Jacqueline McBride/LLNL Above: Engineer John Harris prepares the vacuum test chamber used to subject high-gradient insulators (HGIs) to highvoltage electric fields. The HGI is the candidate dielectric wall material that will be used for the beam tube in LLNL?s compact proton-beam accelerator. Since it can sustain a very high electric field parallel to its surface, it will be able to provide a high accelerating gradient for the proton beam. Below: A time-integrated open-shutter photo of an HGI flashing over in a 150,000- to 200,000-volt-per-centimeter electric field. Elevating the flashover threshold of these insulators is key to the success of the project. BBd/2008 59
Proton-Tomotherapy In the Works: Compact, Low-cost Proton Therapy System It looks like proton therapy will be developed into a compact device, after a technology transfer agreement between Lawrence Livermore National Laboratory and TomoTherapy Inc., a Madison, Wisconsin company, was announced just a few days ago. The DWA, currently being built as a prototype at Livermore, can accelerate protons to up to 100 million electron volts in just a meter. A two-meter DWA could potentially supply protons of sufficiently high energy to treat all tumors, including those buried deep in the body, while fitting in a conventional radiation treatment room. medgadget.com/archives/nuclear_medicine BBd/2008 60
Intensity Modulated Proton Therapy (IMPT) BBd/2008 61 www.europhysicsnews.com/.../article6.html
Fixed Field Alternating Gradient BBd/2008 62
Skillnader mellan olika fabrikat (konventionella linjäracceleratorer) Elekta Varian Siemens 1. Traveling Wave 2. Magnetron 3. Flying wedge 4. 3 fotonenergier 5. Slalom böjmagnet 6. MLC, 80 blad 7. MLC placerad ovanför kollimatorerna 8. Dubbla spridningsfolier 9. Diod-GUN 10.Modulator med tyratron 11.Step and shoot IMRT 12.MLC linjär rörelse 13.Starttid: ca 2 sek 14.Tillverkas i England 15.Ingen doshastighetsreglering 1. Standing Wave 2. Klystron 3. Dynamisk wedge 4. 2 fotonenergier 5. 270 böjmagnet 6. MLC, 120 blad 7. MLC placerad under kollimatorerna 8. Dubbla spridningsfolier 9. Triod-GUN 10.Modulator med tyratron 11.Sliding window IMRT 12.MLC linjär rörelse 13.Starttid: ca 200 ms 14.Tillverkas i USA 15.Lägger till PRF-pulser 1. Standing Wave 2. Magnetron, klystron 3. Dynamisk wedge 4. 2 fotonenergier 5. 270 böjmagnet 6. MLC, 82 blad 7. MLC placerad under kollimatorerna 8. Dubbla spridningsfolier 9. Diod-GUN 10.Kompakt modulator 11.Sliding window IMRT 12.MLC cirkulär rörelse 13.Starttid ca 200 ms 14.Tillverkas USA 15.Spänningsstyrd oscillator BBd/2008 63