| Comparison Study of portal dosimetry with PTW 2-D array system for IMRT for specific QA in Breast Cancer patients |
| Paper ID : 1051-ISCBAS |
| Authors |
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afnan mahmoud Mohamed abd elrahman * university El hussein hospital |
| Abstract |
| IMRT technique is the most common radiotherapy technique used to treat cancer. The portal dosimetry system and 2-D array system are widely used as relative dosimetry detectors for the planar dose comparison of treatment planning system (TPS) vs. measured dose, because of their consistency in results, less time-consuming, and ease to use. - In this work, twenty cases of dynamic IMRT plans were selected for the patient-specific QA study using portal dosimetry and a 2-D array system. Planar dose comparison was carried out with gamma criteria of 3% -3 mm (dose difference and distance-to-agreement (DTA). For the portal, dosimetry system area gamma, average gamma, and maximum gamma were analyzed and for the 2-D array system, the % of pixels passing the 3%-3mm gamma was chosen. The methods tested here based on IMRT breast irradiation can be used in breast cancer if the dose calculation is within the scanners' field of view. We intend to use it for IMRT in pre-treatments to help select Pγ%< 1 point and relevant transition criteria to assess the reproducibility of treatment fractions. Compared to a 2D Array system., although the 2D array has limited sampling capabilities, Conclusion in comparison the portal dosimetry soft for portal imager device (EPID) has a good result for breast cancer plan evaluation versus 2D array results and agreement with international publish data, in addition, reduces the time for calibration due to there is no need for extended cable for measurement is compared with a 2D array |
| Keywords |
| Key Word: Portal dosimetry, IMRT, radiotherapy, breast cancer |
| Status: Abstract Accepted (Oral Presentation) |