1. Tomotherapy
Tomo는 tomotherapy사가 개발하였고 현재는 accuray사가 인수하여 운영하고있다.
이세림
이재성

2. CONTENTS · History · Organization · Principle of operation
· Features and benefits
· Course of treatment
· limitations

3. HISTORY TomoTherapy evolved from CT scanners
CO 60
1955
1972
Clinac 4
1988
EPID
MLC
1995
Serial
tomotherapy
(1st commercial IMRT)
2001
IMRT
2003 CT
Guided
IG-IMRT
(TomoTherapy)
2008
RapidArc
IMAT
Radiotherapy History – C-Arm Gantries
1992 3D
Treatment
1996
1968
(commercialized versions)
1983
MRI
Helical CT
Helical
Multi slice CT
2002
PET/CT use
common
In RT
Imaging History – Ring Gantries
2005
CBCT
Commercial Availability
Helical TomoTherapy
C-Arms invented
for diagnostic X-Rays
Early 1900s
TomoTherapy evolved from CT scanners
TomoTherapy is the new paradigm in IG-IMRT.
Adaptive
Planning
DGRT
Dose Verification
2007
StatRT
Throughput and Reliability Enhancements

4. Organization

5. Organization

6. ORGANIZATION Tomo Linac Detector · 기존 Linac과 구조는 동일
· 3.5MV(Image), 6MV
Detector
· A-Se

7. ORGANIZATION

8. ORGANIZATION MLC(Multileaf Collimator) · 동영상
· 종양의 다양한 모양과 크기에 맞춰 정상장기를 차폐
· 여러 개의 Bar모양의 차폐체(Stepping motor를 이용하여 구동)
· 64(6.25mm)개
· 주로 W이나 WHA
· 동영상
텅스텐 사용이유 납보다 밀도 두 배 높아서 차폐율이 높다.
속도는 250cm/s(보통 Linac의 MLC는 2cm/s)

9. ORGANIZATION Magnetron · 고주파를 발생시키는 장치 · 구조가 간단하여 소형 장치에 이용
· 조작이 용이하며, 가격이 저렴
· 수명이 짧다
· 출력의 안정성이 나쁘다

10. ORGANIZATION Gun board Pulse forming network · Linac의 filament에 전압을 공급
· Linac에 고전압(6MV)을 공급
Pulse forming network
· 이중 고전압전류를 조절하는 회로

11. ORGANIZATION Modulator Beam stop · Magnetron에 고전압 공급
· Cathode에 Heater(Fliament) 전압을 공급
Beam stop
· 1차 차단
· 차폐 벽 두께 줄임

12. What is tomotherapy · Dedicated equipment for IMRT
· Tumors confined to the high-dose radiation therapy may be possible
· Treatment can be performed at the same time(if you need to)
·Currently, IGRT is to implement

13. Tomo
Therapy

14. Principle of operation
· 동영상

15. Principle of operation

16. Principle of operation
6 MV Linac
Electron beam
Target
Whole treatment head rotates around y -axis, with an SAD of 85 cm x z y
Binary multileaf collimator
y-jaws
Photons
A short 6 MV linac is collimated by jaws and a binary multileaf collimator. The treatment head rotates on a gantry in the x/z plane while a patient is continuously translated through the bore of the machine in the y-direction – the therapy analogue of spiral CT

17. Features and benefits
· 동영상

18. Course of treatment

19. What is IMRT
· An advanced mode of high-precision radiotherapy that uses computer-controlled linear accelerators to deliver precise radiation doses to a malignant tumor or specific areas within the tumor
· Currently, most extensively to treat cancers of the prostate, head and neck, and central nervous system

20. IMRT

21. 3D CRT and IMRT

22. IMRT and ARC
IMRT
forward IMRT
inverse IMRT
Static
Arc
Vmat
Tomo

23. IMRT and ARC

24. What is IGRT
· The use of frequent imaging during a course of radiation therapy to improve the precision and accuracy of the delivery of treatment.
· It is possible to re-plan

25. IGRT

26. LIMITATIONS · Only coplanar beams · Constant tx parameters
- Gantry speed
- Table speed
- Beam width(affects longitudinal modulation)
- Dose rate
· No static beam for simple case
· Only 6MV & no electrons
· Hot dose & Interval
추가적 단점으로 HOT DOSE

27. Thank you