The accuracy of a commercial ion chamber array (2D ARRAY-729)‎ in the measurement of beam profiles for siemens physical wedges

Abstract EN

This study was performed in Alexandria Ayadi Al-Mostakbal Oncology Center in Alexandria, Egypt.

The 6 MV Primus, Siemens linear accelerator (linac) was used in this study.

The nominal 15, 30, 45, and 60 degrees wedge filters were used.

The data was acquired using two measuring tools.

The first was a commercially available PTW MP3-s water scanning system (PTW, Freiburg, Germany).

The radiation of photon beam was detected via two 0.125 cm3 ion chambers one serves as a reference chamber, while the second scans the radiation beam.

The surface of water was adjusted at 100 cm source-to-surface distance (SSD).

The profile was scanned at 5 cm depth in water.

The second tool was the 2D ARRAY-729 (PTW, Freiburg, Germany).

The SSD was set at 100 cm and the 2D ARRAY-729 reference point of measurement was then located at 105 cm from the radiation source.

The results revealed that the measurements of wedge-modulated fields matched very well the ion chamber dose profiles acquired in water tank.

Therefore, the 2D ARRAY-729 is a diametrically accurate and useful device for the wedge beam-profile measurements.