An open mouth view xray is a special view to visualize upper cervical spine problems. In routine an anteroposterior cervical spine view shows the spine from C3 segment and is usually less helpful in diagnosing acute injuries.
The open mouth view is essential for excluding a C1 arch or odontoid process fracture. Odontoid process is part of second cervical vertebra that projects upward to articulate with C1 vertebra.
This view is also called Odontoid view.
It is a very useful view in traumatic injuries of upper cervical spine.
How This View Is Taken
The position is same as for an anteroposterior view. In supine position the patient has to open her mouth widely and xray beam is projected through the open mouth.
It is important that patient opens the mouth as widely as possible to visualize the structures properly. Otherwise the structures may get obscured by jaw bones and teeth.
What Is Looked For?
- Anatomy of C1-C2 vertebrae
- Dens or Odontoid process
- Lateral masses of C1 vertebra
- Malalignment or fracture of vertebra
How Does Normal Xray Look Like
Image Credit: KMLIAU
[...] visualization of the upper cervical spine requires either an open-mouth odontoid view. Normally symmetrical articulating occipital condyles, C-1 lateral masses, and C-2 superior [...]