Optimal C-arm angulation along a plane from CT

I am referring to image rotation:

For a specific anatomical orientation (RAO/LAU, CRA/CAU) the up direction in the image is not constrained by a simple sequential rotation around two orthogonal axes, but the image can be rotated due to several reasons:

  • Simple software rotation
  • C-arm base rotation: up direction for a specific anatomical orientation depends on the C-arm base angle (or wig/wag). Floor-mounted systems automatically compute anatomical angles that take into account the base (L-arm) angle.
  • On some systems the detector can be rotated completely independently:

Philips Allura:

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