أجهزة العلاج الإشعاعي Clinical Radiation Generator

1. أجهزة العلاج الإشعاعيClinical Radiation Generator إعـداد  م. أنور صلاح عطاالله Clinical Radiation Generator

2. المعالجة الإشعاعية Radiotherapy استخدام الإشعاع المؤين في معالجة السرطان Using the ionizing Radiation to treat cancer معالجة خارجية(عن بعد) External Beam Therapy (EBT) معالجة داخلية(عن قرب) Brachytherapy Clinical Radiation Generator

3. Radiotherapy • One of the main treatment modalities for cancer (often in combination with chemotherapy and surgery) • It is generally assumed that 50 to 60% of cancer patients will benefit from radiotherapy • Minor role in other diseases Siemens Oncology Clinical Radiation Generator

4. External Beam Radiotherapy Beam 2 Beam 3 Beam 1 tumor patient Clinical Radiation Generator

5. Clinical Radiation Generator

6. External Beam Radiotherapy • More than 90% of all radiotherapy patients are treated using EBT • Most of these are treated using X-rays ranging from 20keV to 20MeV in peak-energy • Other EBT treatment options include telecurie units (60-Co and 137-Cs), electrons from linear accelerators and accelerators for heavy charged particles such as protons Clinical Radiation Generator

7. Cancer incidence (WHO) Clinical Radiation Generator

8. Major indications for radiotherapy • Head and neck cancers • Gynaecological cancers (eg. Cervix) • Prostate cancer • Other pelvic malignancies (rectum, bladder) • Adjuvant breast treatment • Brain cancers • Palliation Clinical Radiation Generator

9. Approaches • Palliative radiotherapy to reduce pain and address acute symptoms - eg bone metastasis, spinal cord compression, ... • Radical radiotherapy as primary modality for cure - eg head and neck • Adjuvant treatment in conjunction with surgery - eg breast cancer Clinical Radiation Generator

10. To kill ALL viable cancer cells To deliver as much dose as possible to the target while minimising the dose to surrounding healthy tissues Aim Patient Critical organs target Beam directions Clinical Radiation Generator

11. Prognostic Factors • Cancer type and stage • Patient performance • Radiation dose • ... Good prognosis survival Bad prognosis time Clinical Radiation Generator

12. Prognostic Factors • Cancer type and stage • Patient performance • Radiation dose • ... Accurate dose delivery matters! Clinical Radiation Generator

13. Dose should be accurate • To target: • 5% too low - may result in clinically detectable reduction in tumour control (eg. Head and neck cancer: 15%) • To normal tissues: • 5% too high - significant increase in normal tissue complication probability = morbidity = unacceptable side effects Clinical Radiation Generator

14. External beam radiotherapy (EBT) treatment approaches • Superficial X-rays • Orthovoltage X-rays • Telecurie units • Megavoltage X-rays • Electrons • Heavy charged particles • Others Clinical Radiation Generator

15. Superficial X-rays Orthovoltage X-rays Telecurie units Megavoltage X-rays Electrons Heavy charged particles Others External beam radiotherapy (EBT) treatment approaches • 40 to 120kVp • 150 to 400kVp • 137-Cs and 60-Co • Linear accelerators • Linear accelerators • Protons from cyclotron, C, Ar, ... • Neutrons, pions Clinical Radiation Generator

16. Superficial radiotherapy • 50 to 120kVp - similar to diagnostic X-ray qualities • Low penetration • Limited to skin lesions treated with single beam • Typically small field sizes • Applicators required to collimate beam on patient’s skin • Short distance between X-ray focus and skin Clinical Radiation Generator

17. Superficial radiotherapy Philips RT 100 Clinical Radiation Generator

18. Superficial radiotherapy issues • Due to short FSD high output and large influence of inverse square law • Calibration difficult (strong dose gradient, electron contamination) • Dose determined by a timer - on/off effects must be considered • Photon beams may be contaminated with electrons from the applicator Clinical Radiation Generator

19. Orthovoltage radiotherapy • 150 - 400kVp • Penetration sufficient for palliative treatment of bone lesions relatively close to the surface (ribs, spinal cord) • Largely replaced by other treatment modalities Clinical Radiation Generator

20. Clinical Radiation Generator

21. Clinical Radiation Generator

22. Kilovoltage Equipment (150 - 400 kVp) • Depth dose dramatically affected by the FSD FSD 6cm, HVL 6.8mm Cu FSD 30cm, HVL 4.4mm Cu Clinical Radiation Generator

23. Like for superficial irradiation units the beam is set-up with cones directly on the patient’s skin Orthovoltage patient set-up Clinical Radiation Generator

24. Megavoltage radiotherapy • 60-Cobalt (energy 1.25MeV) • Linear accelerators (4 to 25MVp) • Skin sparing in photon beams • Typical focus to skin distance 80 to 100cm • Isocentrically mounted Clinical Radiation Generator

25. مع أطيب الأمنيات Clinical Radiation Generator