QA of LINAC machines
Embed Size (px)
Transcript of QA of LINAC machines
DAILY QUALITY ASSURANCE PROCEDURELINAC 2MUHAMMAD SOHAIL PREPARED BY :
Quality Assurance of LINAC Machines : To ensure the consistency of quality of machine.
Patient safety important.
To ensure that it deliver right dose to the patients.
To check if there is any mechanical or software errors.
TURN ON PROCEDURE
MACHANICAL CHECKS WARMUP PROCEDURE
TURN ON PROCEDURE First step turn on power keys
Second step turn on the control cabinet key (Make it horizontal). Third step turn on IRM (In-Room Monitor)
Fourth step turn on 4D Console
MACHANICAL CHECKSRotate gantry & Collimator at 0 degree.
Then turn on HyperTerminal MLC.
Check Couch movement(LAT,LNG,VRT) and Breaks manually and motorized. Check all safety measures.
Check ODI (optical density indicator) with the help of front pointer array set on 100 cm
ODI exact set on 100 cm SSD on couch and both lateral laser should be touch the edges of couch.
Field size should be set on 20x20 at 100 cm SSD on Field Card.
Check water temperature , system pressure, SF 6(Sulfur Hexafluoride) gas pressure and water level . These value enter online in Morning checkout .
Insert accessory mount at gantry then insert applicator size 15x15 with cutout tray. warm-up machine .We have five electron energies 6MeV,9MeV,12MeV,15MeV, 18MeV all electron energies run during Morning QA.WARMUP PROCEDURE
We have two photon energies 6MV and 18MV photon run during Morning QA for Warm-Up machine.
We are check beam interlocks, and beam indicator lights on daily Morning QA. we have some checks of beam interlock's .
Key turn on and turn offBeam off button Backup counter LPO button Door interlock
We have some parameters apply during Morning QA on checkmate 2 phantom.
Checkmate2 set on central axis.Field size should be set on 15x15 Gant.0 coll.0 SSD set on 122cm. We get some references value during dosimetry 6MV 18MV photon and 6MeV electron on daily basis. Checkmate 2 phantom have 8 channels (A2,A3,A4,A5,A6,A7,A7) each channel calibrate to each energy Exp: A2 calibrate for 6MV, A3 calibrate for 18MV. One is calibrate for electron day by day.
PARAMETERS & PROTOCOLNOTE: Deliver 100 MUs, the electrometer reading should be within 98% CPD 102%, tolerance level is 2% . If there are unusual observation or reading are beyond the tolerance then consult Physicist before treating the patients.
DOCUMENTATIONWe have a QA sheet after QA we taken values documented in QA sheet. With two RTT Signature