210 likes | 416 Views
Set-up/Verify & Treatment. Diagnostic -Imaging. Planning. The Patient Pathway Set-up/Verify and Treatment. Treatment Delivery Radiation Therapy . Rajinder Singh Dhada, MBA Elekta Inc. Types of Radiation Treatments. X-rays and electrons – Linear Accelerator X-rays 4MV to 25MV
E N D
Set-up/Verify & Treatment Diagnostic -Imaging Planning The Patient PathwaySet-up/Verify and Treatment
Treatment DeliveryRadiation Therapy Rajinder Singh Dhada, MBA Elekta Inc.
Types of Radiation Treatments • X-rays and electrons – Linear Accelerator • X-rays 4MV to 25MV • Electrons 4MeV to 22MeV • Gamma rays • Cobalt 60 machines • Elekta Gamma Knife • Iridium wires • Brachytherapy • Particle Therapy • Protons, Carbon Ions
Types of Radiation Brachytherapy • Low-Dose-Rate (LDR) • Radiation delivered over the course of 48 to 120 hours • High-Dose-Rate (HDR) • High energy source delivers the dose in a matter of minutes rather than days HDR brachytherapy for breast cancer using MammoSite catheter (B) with an Iridium-192 source (A) and a high-dose-rate afterloader (C). This is an example of a temporary high-dose-rate implant.
Radiation Dose Fractionation • Prescribed dose delivered in fractions • number of fractions within prescribed duration (e.g. 5 weeks) • single fraction (Stereotactic Radiosurgery (SRS)) • Multiple fractions • Daily • Weekly • Radical - more fractions to higher total dose • Palliative - fewer fractions to a lower total dose
Modern Radiation Treatment Delivery Systems Accuray - CyberKnife Tomotherapy Hi-Art IBA Protons Elekta Gamma Knife - Perfexion
5 Set-up and verify 4 Verify treatment plan 6 Treat Basic treatment workflow…. • Q/A the prescription as sent from the treatment planning system • Set-up the patient for treatment & verify position • MV or kV imaging • Deliver radiation daily over a period of time
Common Treatment Delivery Techniques • 3D-CRT - Three-dimensional conformal RT • Fields shapes fixed to tumor shape • IMRT - Intensity modulated RT • A sophisticated form of 3D-CRT • Field shape changes to match tumor size/shape • SBRT – Stereotactic RT • Higher doses, smaller fields, over 1 – 2 weeks Nine-field IMRT head and neck 3-D schematic.
Treatment Delivery - Dose painting with IMRT Why IMRT …… • Highly conformal • Minimize dose to healthy tissues Head & Neck
Linear accelerator head with multileaf collimator Linear accelerator with multileaf collimator Target Treatment Delivery Treatment normally delivered over several weeks
Rotational IMRT - Treatment Delivery • Radiation delivered while machine rotates • Dynamic IMRT delivery while rotating • Volumetric Modulated Arc Therapy (VMAT) • Helical Delivery Technique
Delivery SystemQA Roles and Responsibilities • Manufacturers • Design QA (Validation & Verification ), • Production QA, Testing • Installation • Equipment meets defined specification, • User (supervised by Medical Physicist) • Commissioning/Acceptance • Clinical specific • Equipment & Process QA • Recurring – daily, monthly, annual • Per patient Treatment Plan
Set-up/Verify & Treatment Diagnostic -Imaging Planning The Patient PathwayRadiation Therapy Treatment