How to define proton range(R80)?

[MPstudentMU]

Dear all

I’m a master degree student in medical physic. I would like to define R80 in proton planning from matrad. So, I curious that can I define R80 from the dose profile? And Could you give any suggestions for validating the result?

Regards

[wahln]

What do you mean with

I would like to define R80 in proton planning from matrad?

The range is given in the base data or can be computed with the range-energy-relation? Or do you want to find it in a heterogeneous 3D dose distribution?

[MPstudentMU]

Thank you for your answer, I mean I would like to find the range in heterogeneous 3D dose distribution, like in real patient data. Dose it can find from this dose profile that created from the matRad plan ?

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[wahln]

Okay, but there should be more than one range in this picture, right? Because the SOBP is composed of multiple bragg-peaks of different energies and thus different ranges. So you could detect the distal edge, i.e. using the profiles above - is that what you want?

[MPstudentMU]

I greatly appreciate it. I have a small question I would want to ask you. Does this profile result from the center of the beam direction?