• Patients are in prone or seated erect position with the arms in comfortable position and adjust shoulders to lie in the same transverse plane.
• Midsagittal plane of the patient head is center to the midline of the grid.
• Adjust flexion of the neck so orbitomeatal line forms an angle of 37 degrees with the plane of the film.
• Midsagittal plane is perpendicular to the plane of the film.
• Immobilize the head and center the cassette at the level of acanthion.
Central ray is perpendicularly to exit the acanthion.
Structure shown: axial image of the facial bones is presented. Orbits, maxillae and zygomatic arches are well shown.
Evaluation criteria: distance between the lateral border of the skull and orbit should be equal on each side. Petrous ridges should be projected immediately below the maxillae.
