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5 Cards in this Set
- Front
- Back
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AP |
No rotation= Petrous ridges symmetrical Dorsum sellae and posterior clinoids visualized in the foramen magnum indicate proper CR angulation and proper flexion/extension of the neck. Underangulation/insufficient flexion = dorsum sellae superior to the foramen magnum Overangulation/excessive flexion = superimposes the posterior arch of C1 over the dorsum sellae in the foramen magnum and produces foreshortening of the dorsum sellae. Shifting of the anterior and posterior clinoids laterally within the foramen magnum indicates tilt. |
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Lateral |
Sella turcica, clivus, and entire cranium in profile. No rotation or tilt of the cranium is evident. Rotation = anterior and posterior separation of symmetric vertical bilateral structures of EAM, mandibular rami, and greater wings of sphenoid Tilt = inferior and superior separation of symmetric horizontal of orbital roofs (plates) and greater wings of sphenoid |
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PA Caldwell |
15 degrees caudal Exiting nasion No patient rotation = equal distance from the mid lateral orbital margins to the lateral cortex of the cranium on each side; symmetric superior orbital fissures within the orbits; correct extension of the neck (OML alignment) Petrous ridges projected into the lower 1/3 of the orbits. Supraorbital margin visualized without superimposition. |
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PA 25-30 degrees caudad |
Exits nasion No patient rotation = equal distance from the mid lateral orbital margins to the lateral cortex of the cranium on each side; symmetric superior orbital fissures within the orbits; correct extension of the neck (OML alignment) Petrous ridges projected at or just below the IOMs to allow better visualization of the entire orbital margin Foremen rotundum is adjacent to each IOM that is visualized Symmetric superior orbital fissures within the orbits Inferior orbital rim region |
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PA 0 degrees |
Exits glabella Frontal bone No patient rotation = equal distance from the lateral orbital margin to the lateral cortex of the skull Petrous ridges fill the orbits and the level of supraorbital margin Posterior and anterior clinoids visualized just superior to the ethmoid sinuses |
