Combine 2 ct volumes into one

I have 2 ct of same patient of 2 half bodys overlapping, one from head to pelvis and second from pelvis to feet.

I want to combine them into one, i’m going with this workflow:

first i enlarge body section to body_extended volume using crop volume module setting -1000 to the fill value and linear as interpòlator.

Nexti register two images body_extended and legs manually with transform module then with brains general registration ok.

now i have to combine two cts into one, i think a tool that can compare boxel by boxel and select maximun value would do the job but i cant find that tool.

I try to use add scalar volumes module but in the legs section the hu value isnt correct as it shows good value for bones (1000) but bad for muscle (-xxx) i think thats because it is linearly scalinf from body_extended (-1000) to leg values (say 100) and then it outputs something in range -xxx…

please may any help with this issue

thank you,


This material should help:

Very much thank you for your answer, i’ve managed to get the job done with the tool you posted. nevertheless i would like to dig into the details and know if this can be done manually with the tools included default

after play a little more with the modules i have reproduced what is done by the stitch script:

  1. use module resample image brains, image to warp is the smallest image in my case the legs, and reference image the bigger in my case body_extended. i have to use pixel tipe as short and linear interpolation with default value=-1000

  2. go to the simple filters module named “maximunimagefilter” put the two volumes and then you get the combined ct

problem is solved after this thank you!!! any correction or improvement would be apreciated!!

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