How to calculate an isocenter: 3D po-gel dosimeter



The Isocenter option enables the processing of CT data, incl. 3D polymer gel dosimetry, towards the calculation of the isocentre in radiotherapy under the control of CT (CT-guided radiotherapy).


The polyGeVero-CT software package can also process files generated by the compatible polyGeVero software package (works e.g. on MRI, CT and OCT data). Therefore, the isocenter option in polyGeVero-CT can also be used for MR-guided radiotherapy by processing 3D dosimetry data with polyGeVero software, and then exporting files for polyGeVero-CT processing to determine the isocenter.


This movie demonstrates the isocenter calculation (3D po-gel dosimeter) for a 3D polymer gel dosimeter. The following operations were performed:

  • CT scanning of a background 3D polymer gel dosimeter
  • CT scanning of an irradiated 3D polymer gel dosimeter
  • averaging CT data after three CT scans
  • subtracting background from irradiated 3D polymer gel dosimeter.

The above step operations are not shown in the movie. They can be seen in another movie: How to process example CT data.


The results from step operations were saved as a project and the project is imported in polyGeVero-CT for determination of isocenter.


The data is processed to find out the isocenter by using a template in 2D mode.


Notice that the CT signal for irradiated 3D polymer gel dosimeter is enhanced and the intersecting beams are clearly seen after background subtraction.