[Vv] Issue with PET images

[Lombardo, Elia]

Dear vv team,

Me and my colleagues are using vv to preprocess PET Dicom images for a project.

When opening some of the Dicom images in vv we see many  'black islands', i.e. areas with large negative values (top row in the image below). We then turn the negative values to positive values for the island areas, convert dicom to mha and get a reasonably well looking image (bottom row).
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However, we checked the exact data value in a few points of interest and compared it with the PET values displayed when opening the original dicom in a Raystation TPS and saw some discrepancies (e.g. in Raystation we get a value of 34000 while in the corrected mha opened in vv we have 31000).

Is this issue known?

Thanks in advance for your help!

Best,
Elia Lombardo, M.Sc.
Medizinische Physik / Medical Physics

LMU Klinikum
Klinik und Poliklinik für Strahlentherapie und Radioonkologie

Campus Großhadern  | Marchioninistraße 15  |  81377 München
Tel. 089 4400-73757
Elia.Lombardo at med.uni-muenchen.de<mailto:Elia.Lombardo at med.uni-muenchen.de> | www.lmu-klinikum.de/strahlentherapie-und-radioonkologie<http://www.lmu-klinikum.de/strahlentherapie-und-radioonkologie>

Das Klinikum der Universität München ist eine Anstalt des öffentlichen Rechts (AöR)

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