error in TOF results

Dear CASToR users

I used the castor3.0.1 to reconstruct a PET data of some cylindrical phantoms and I used different TOF_reso values and also non TOF case. But I found that the SNR value of the non TOF was bigger than the TOF cases of 400,300,200 ps ( with decreasing the TOF value the SNR decreased) . Should I modify the TOF command in Cdh file to apply the TOF on the image quality? Did anyone face this issue?

Thank you so much.

Dear Hadi,

Are you using the same dataset for your different reconstructions ?


Hi Simon
Thank you for your reply
Yes, I used the same dataset for all reconstructions.
Best regards

Hi Hadi,

Do you mean that you simulated PET data with different scanner TOF resolutions, and then tried to reconstruct the data with the corresponding TOF resolution?

I don’t understand your question about TOF command, could you reformulate please?

Sorry I didn’t see the previous message. If you use a wrong TOF resolution in the reconstruction, different from the nominal TOF resolution of the scanner, it is normal that you get issues in the reconstruction.

Hi Marina
I am sorry if my message is not clarified. I simulated a PET data at one time ( I didn’t change the PET scanner) but I reconstructed this data with different TOF values.

also I used this command: “./castor-GATERootToCastor -i myroot.root -m mymac.mac -o output300 -s output300 -geo -k -TOF_reso 300”
Best regards