Compute Head Model Error

Hi All,

I got this error when I try to compute the head model.
The link is the zip file including all all the anatomy information. (https://mcgill-my.sharepoint.com/:u:/g/personal/siyu_long_mail_mcgill_ca/EQ41QBGn6RlOgqZGkKu6rTkBtdni2kwVK8qxwQPn2Me3Cg?e=JLmhqm).
Do you have any solution?


** Error: OpenMEEG call: om_assemble -HM
** "/home/rkarakis/.brainstorm/tmp/openmeeg_231010_210331/openmeeg.geom"
** "/home/rkarakis/.brainstorm/tmp/openmeeg_231010_210331/openmeeg.cond"
** "/home/rkarakis/.brainstorm/tmp/openmeeg_231010_210331/openmeeg_hm.mat"
** OpenMEEG error #1:
** ./om_assemble version 2.4.1 compiled at Aug 29 2018 08:19:44 using OpenMP
** Executing using 6 threads.
**
** | ------ ./om_assemble
** | -HM
** | /home/rkarakis/.brainstorm/tmp/openmeeg_231010_210331/openmeeg.geom
** | /home/rkarakis/.brainstorm/tmp/openmeeg_231010_210331/openmeeg.cond
** | /home/rkarakis/.brainstorm/tmp/openmeeg_231010_210331/openmeeg_hm.mat
** | -----------------------
** (DEPRECATED) Please consider updating your geometry file to the new format 1.1 (see data/README.rst): /home/rkarakis/.brainstorm/tmp/openmeeg_231010_210331/openmeeg.geom
** This geometry is a NESTED geometry.
** Info:: Mesh name/ID : 1
** # vertices : 1922
** # triangles : 3840
** Euler characteristic : 2
** Min Area : 8.76184e-06
** Max Area : 8.50929e-05
** Info:: Mesh name/ID : 2
** # vertices : 1922
** # triangles : 3840
** Euler characteristic : 2
** Min Area : 8.93419e-06
** Max Area : 8.61097e-05
** Info:: Mesh name/ID : 3
** # vertices : 1922
** # triangles : 3840
** Euler characteristic : 2
** Min Area : 8.21848e-06
** Max Area : 6.5237e-05
** Info:: Domain name : Scalp
** Conductivity : 1
** Composed by interfaces : +1 -3
** Interface "1"= { mesh "1" }
** Interface "3"= { mesh "3"(outermost) }
** Info:: Domain name : Skull
** Conductivity : 0.0125
** Composed by interfaces : +2 -1
** Interface "2"= { mesh "2" }
** Interface "1"= { mesh "1" }
** Info:: Domain name : Brain
** Conductivity : 1
** Composed by interfaces : -2
** Interface "2"= { mesh "2" }
** Info:: Domain name : Air
** Conductivity : 0
** Composed by interfaces : +3
** Considered as the outermost domain.
** Interface "3"= { mesh "3"(outermost) }
** !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
** !!!!!!!!!!! WARNING !!!!!!!!!!!
** !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
** 2 meshes are intersecting !
** Info:: Mesh name/ID : 1
** # vertices : 1922
** # triangles : 3840
** Euler characteristic : 2
** Min Area : 8.76184e-06
** Max Area : 8.50929e-05
** Info:: Mesh name/ID : 3
** # vertices : 1922
** # triangles : 3840
** Euler characteristic : 2
** Min Area : 8.21848e-06
** Max Area : 6.5237e-05
** !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
** !!!!!!!!!!! WARNING !!!!!!!!!!!
** !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
** 2 meshes are intersecting !
** Info:: Mesh name/ID : 2
** # vertices : 1922
** # triangles : 3840
** Euler characteristic : 2
** Min Area : 8.93419e-06
** Max Area : 8.61097e-05
** Info:: Mesh name/ID : 3
** # vertices : 1922
** # triangles : 3840
** Euler characteristic : 2
** Min Area : 8.21848e-06
** Max Area : 6.5237e-05
**
** For help with OpenMEEG errors, please refer to the online tutorial:
** https://neuroimage.usc.edu/brainstorm/Tutorials/TutBem#Errors


Thank you!
Siyu

Hi @siyu210

it seems two surfaces of your head model are intersecting,

image

You need to regenerate the BEM surfaces and check visually if they are not intersecting.

Thanks for your response! The inner and outer surface were both generated from 'MRI Segmentation/ Generate BEM Surfaces'. In this case, what should I do to avoid the intersection?

Hi! The inner and outer surface were both generated from 'MRI Segmentation/ Generate BEM Surfaces'. In this case, what should I do to avoid the intersection?

Can you share a screenshot of the surfaces?

What methods did you use to generate these BEM surfaces

I chose the Brainstorm method, here is the image of both outer and inner surface (the transparency of outer is 0).

Hi @tmedani
I'm post the screenshot above!