4. RT SIMULATION.pdf

RADIOTHERAPY SIMULATION Santhekumari Sithamparam  RADIOTHERAPY SIMULATION Gross Tumor Volume (GTV) Clinical Target Volume (CTV) Planning Target Volume (PTV) Treated Volume Irradiated Volume Organ at Risk (OAR) Simulation procedure Patient surface marking...

RADIOTHERAPY SIMULATION Santhekumari Sithamparam  RADIOTHERAPY SIMULATION Gross Tumor Volume (GTV) Clinical Target Volume (CTV) Planning Target Volume (PTV) Treated Volume Irradiated Volume Organ at Risk (OAR) Simulation procedure Patient surface marking Guidelines ICRU 50 & ICRU 62  Virtual Simulation 3D Model of the patient and the Treatment Devices Anwar 10  Convenntional Simulator Rotating gantry Diagnostic X-ray tube Radiation beam defining system Simulator couch Image intensifier and X-ray film holder Nucletron/Oldelft Anwar 11 Conventional simulation procedure Prepare the simulation room. Get the positioning devices ready on the simulator couch. Greet the patient. Identify the correct patient. Ask the patient to remove any radiopaque materials around the simulation area. Help the patient to get on and lie on the couch. Position the patient, make sure patient is comfortable and maintain communication with the patient. Identify surface landmarks that are related to the simulation area. Raise the couch, draw reference marks on patient’s skin. Conventional simulation procedure Make sure gantry and couch is at 00 Align the patient visually and with lasers. Fabricate the immobilization device if required. Raise the image intensifier close to the couch. Start screening Determine treatment field borders. Conventional simulation procedure Take localization radiographs. Mark the centre of field or field borders on patient skin. Tattoo at the treatment filed centre, superior and inferior to the centre. Laterally tattoo at the patient’s body. Take patient outline/contour. Take reference landmark. Document treatment parameters on simulation sheet. Lower the couch Assist the patient to get down from the couch. Conventional simulator radiographs  Tatoo 1. Laser beams are used to mark 2. Supplies for tattooing. the treatment area with a The area is first cleaned with marker. alcohol. 5. The small bluish dot in the center of this image is the tattoo. 3. A drop of India ink is placed on 4. A needle is used to puncture the top layers the mark. of the skin, getting the ink under the skin and creating the tattoo.  CT-simulation procedures Prepare the CT-sim room. Get the positioning devices ready on the simulator couch. Greet the patient. Identify the correct patient. Ask the patient to remove any radiopaque materials around the simulation area. Help the patient to get on and lie on the couch. Position the patient, make sure patient is comfortable and maintain communication with the patient. Identify surface landmarks that are related to the simulation area. Raise the couch, draw reference marks on patient’s skin.  CT-simulation procedures Align the patient visually and with lasers. Fabricate the immobilization device if required. Identify a suitable origin. Scan the topogram/scanogram Check that patient is straight. Determine the scan area. Inject contrast if required Start scan, check that is whole scan area is covered in the scans.  CT-simulation procedures Tattoo at the treatment filed centre, superior and inferior to the centre. Laterally tattoo at the patient’s body. Take reference landmark Document treatment parameters on simulation sheet. Lower the couch Assist the patient to get down from the couch.