vertebra landmark/morphometry

[msrepo]

Preliminary fail-fast methods:
A new method for the automatic identification of the dimensional features of vertebrae, DOI: 10.1016/j.cmpb.2015.04.003

Campbell, J. Q., & Petrella, A. J. (2015). An Automated Method for Landmark Identification and Finite-Element Modeling of the Lumbar Spine. IEEE Transactions on Biomedical Engineering, 62(11), 2709–2716. doi:10.1109/tbme.2015.2444811

1. initial orientation

[msrepo]

poor man's approximation of symmetry plane

[msrepo]

i am not sure if principal axes visually corresponds to vertebral body width and height.

even when shifting the vertebral body to the origin, the principal axis does not look visually correct way to measure width.

[msrepo]

Estimated

• vertebral body height
• vertebral foramen width
• spinous process width
  

[msrepo]

vertebra normals histogram: the left and right bins correspond to vertical vertebral body boundary points whereas the middle bins correspond to vertebra end plates. The normals were calculated wrt PQ vector.

[msrepo]

the normals wrt PQ does not work. it cannot differentiate between upper and lower endplate. it cannot differentiate between anterior and psoterior boundaries. it does differentiate endplates and ap boundaries.


Use the axis line to differentiate between upper and lower endplate

[msrepo]

spinous process angle and spinous process length

[msrepo]

calculate vertebral body dimensions



not to scale

[msrepo]

to obtain th coronal plane, we start searching for the cut plane

using vol/vol_bbox ratio

but if we do not setup the normals correctly

    potential_coronal_cut = vert_mesh.clone(transformed=True).cut_with_plane(origin=potential_cut_plane_origins[i], normal=(0,0,1), invert=True).cap()

we will cut too much into the vertebral body