Problems with DVH results

Hello every body
Previously I had a problem in installing Flair and I solved it by the help of the User Forum
Currently those my screen shot for my input file and screenshot shows the DVH for comparison the planned and calculated plan .

1- Did I enter any thing wrong in my input file?
2- or is there a missing input?
3- Why the DVH appeared like this in the screenshot?
4- are I downloaded the planned and Fluka plan incorrectly?

Dear @walaa.khalil88,

Let me comment a few things about your post.

  • If you open a thread and in the end your problem is solved, then it would be polite to replying saying it. In this way the person that replied to you would know that you are satisfied and the thread can be closed.

  • Whenever asking question about an inputfile, you should share your .flair or .inp file rather than attaching a series of snapshots of your input.

  • The forum is not intended to validate inputs or simulations from the users, but rather to address specific problem. Only the user knows what he wants to achieve with their simulations, therefore nobody else can say: “the input is good”.

*Concerning your specific question at your points 3 and 4, do you believe there is any specific problem in what you see?

Dear @amario
I’m so sorry for missed understand, I never meant what you understood, and it wasn’t impolite because I didn’t mean anything ,again I’m so sorry for everyone.
for points 3 and 4, the screenshot show in DVH any organ such as eye has dose 0 in fluka plan but in planned TPS has a certain higher dose . Why ?

Dear @walaa.khalil88

could you please provide the input files so we can check the problem?

Dear @vasilis
please can you tell me about any privet account to send you the dicom file, and input file just for patient privacy.

Dear @vasilis
good day for you and for all fluka users.
I sent to you at ( all files that you want to run my project
can you tell me, are you run the project or no?
thank you very much

Dear @walaa.khalil88
I received your files, and I will check them

Looking your project it seems to me that the two BEAMs are not realistic, therefore the unrealistic DVH you obtain. You imported an RTPLAN with two beams each one described by a single spot with a pencil photon beam of 6 MeV and a weight of 1.

Photon RTPLANs can be rather tricky. My guess is that:
The two beams are not supposed to be pencil but should have some lateral spread, which is shaped by some kind of a multi leaf collimator. Moreover, I guess that the beams are described with the use of MU monitor units. flair to convert the MU to proper weight it needs the beam model file

Dear @vasilis
thanks for replayed me
i imported the same beams that found in the treatment plan without change any thing in it so i not understand what is the wrong in it we should not change any thing in the treatment plan
each beam has 6 MV and all the beams have the same calculation point
2- I not understand what the meaning of the lateral spread
already the beams are shaped by a multi leaf collimator according to the size of the target which we want treat it .
3- is the most important question
How i can import the beam model file ?
thankyou very much

Without having the RTPLAN (plus other DICOM) files there is no way to tell if something went wrong in the conversion or not. Flair generated two pencil beams which are not corrected. On other photon plans I’ve seen that the information on the spread of the photon beam as well the multileaf collimator setup was given in external non-DICOM files that flair is unable to parse.
The multileaf collimator you need to model it manually in your geometry.
The beam model you need to create it also manually, and select it in the RTPlan tab of flair.

The beam model, you be edited directly in flair or in any text editor. It should be a simple ASCII file with up to 7 columns as it is shown in the RTPlan

Dear @vasilis
It seems to me that the simulation is very difficult, especially since I am a new user
How The multileaf collimator model manually in the geometry.
and when i want to import the beam model manually, I select create icon in the RTPlan tab of flair. but I not found any file created with ext. dat as show in the figure

For the multileaf collimator, you have to look on our course lectures n geometry and on the fluka manual how to edit the geometry

For the beam model you can edit the information directly inside flair with the help of the + - and clone buttons.
You press the + a new record will appear and then you have to enter the information in the table.
At the end don’t forget to click on the save button to save the beam model in an external file

Dear @vasilis
are we can model beam file automatically or not if not what the meaning of NP per MU, ∆P [Mev\c], ∆©x, ∆©y [mrad]. i mean that what the roles to calculate it

Dear @vasilis
can you send me a screenshot shows the values of the NP per mu, ∆P, ∆©x, and ∆©y (the beam model file) of the case that i send to you. To can compare between them and my calculate to know that my calculate are right or no
i so sorry but i don’t know how calculate them.
i want screen show the beam model file of the case which i send to you.

I do not understand what you mean?
You never send me any beam model. What you attached above in a screenshot was a an image of the RTPLAN showing the summary of the beam / spots.

The beam model is facility depended and is not included in the DICOM files and flair cannot create it automatically. Neither I can provide you something that is facility depended.

You need to find out from your facility for each beam energy what is the conversion from MU (monitor units) to NP (number of primaries), what is the spread in momentum \Delta p the angular spread in horizontal and vertical plane \Delta\phi x,y and the spatial beam spread as FWHM for both horizontal and vertical.

Dear @vasilis
I think that supposed to for each beam e
energy, MU (monitor units) to NP (number of primaries), pread in momentum Δ p, angular spread in horizontal and vertical plane Δϕx, y and the spatial beam spread as FWHM for both horizontal and vertical are found in RTDOSE, and in RTPLAN. Is my understanding right or wrong?

Dear @walaa.khalil88

RTDOSE provides you with the dose distribution in the scoring grid and does not inform you about the beam characteristic which delivered this dose, only the referential number of the RTPLAN dicom file.
RTPLAN provides you information i.a. on the beam energy, beam size at the isocenter, and position of the beam at iso, MU (beam weight).
The missing data are i.a. NP per MU, beam spread etc. since FLUKA does not understand the MU per se… and cannot guess the beam spread from this information.

I highly recommend looking inside the RTPLAN and RTDOSE DICOM files to understand what is inside, and what information these files are covering.
For that, you can use python and pydicom library. There are plenty of different tutorials available online.

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