Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10733610 | Zeitschrift für Medizinische Physik | 2005 | 5 Pages |
Abstract
The two-dimensional verification of intensity-modulated radiation plans is one of the major requirements for the safe application of this technique. The present study examines the resolution and sensitivity of a two-dimensional ionisation-chamber array (PTW2D-Array, type 10024), which can be used for plan verification instead of films. According to the Shannon-Nyquist theorem, the resolution of the 2D-Array is sufficient for dose distributions with a minimal field size of 2 cmÃ2 cm. The minimal field size can be reduced to 1 cmÃ1 cm by shifting the array 5mm in the direction of the MLC movement and by repeating the measurements. The high sensitivity against a monitor decalibration for a single field of a sequence is demonstrated on the basis of an individual case. The minimal threshold for MLC misalignment detected by a chamber of the array is less than 1mm. Therefore, the resolution capabilities of the 2D-Array are sufficient for most intensity-modulated radiation therapy (IMRT) fields.
Related Topics
Physical Sciences and Engineering
Engineering
Biomedical Engineering
Authors
Björn Poppe, Zanzem Atung, George Chofor, Arne Blechschmidt, Armand Djouguela, Ralf Kollhoff, Antje Rubach, Dietrich Harder,