Orbits & EyesOrbits & Eyes

Modified Occipito- mental (baseline 55Modified Occipito- mental (baseline 550 0 to to film)film)

Occipito –frontal with 25Occipito –frontal with 2500- 30- 3000 caudal caudal angulation of the beamangulation of the beam

LateralLateralFor Localization of IOFB – Three Lateral For Localization of IOFB – Three Lateral

projections with the patient looking Up, projections with the patient looking Up, Straight, & Down.Straight, & Down.

Orbits – PA 25Orbits – PA 2500 - 30 - 3000

Orbits – modified OMOrbits – modified OM Median plane Median plane

perpendicular to perpendicular to buckybucky

Inter orbital line Inter orbital line parallel to buckyparallel to bucky

Chin is adjusted to Chin is adjusted to bring the base line bring the base line (plane) at 55(plane) at 5500 to to buckybucky

Central ray Central ray perpendicular and to perpendicular and to pass through a point pass through a point in midline at the level in midline at the level of the inferior orbital of the inferior orbital marginsmargins

Optic ForaminaOptic Foramina

Note :- Note :- The optic canals open into the rear of the bony The optic canals open into the rear of the bony

orbits, that is the optic foramina. The canals orbits, that is the optic foramina. The canals pass forwards and laterally at approximately 35pass forwards and laterally at approximately 350 0 to the median sagittal plane and downwards at to the median sagittal plane and downwards at approximately 35approximately 3500 to the odito-meatal plane, and to the odito-meatal plane, and this is the path the central ray must take to this is the path the central ray must take to demonstrate the foramen.demonstrate the foramen.

Both sides must be done foe comparisonBoth sides must be done foe comparison

Optic ForamenOptic Foramen Position the head so that Position the head so that

The Nose, Zygoma and The Nose, Zygoma and Chin of the side being Chin of the side being examined is in contact with examined is in contact with the buckythe bucky

Orbit in center of the buckyOrbit in center of the bucky Median sagital plane 53Median sagital plane 5300 to to

buckybucky The Acanthiomeatal line The Acanthiomeatal line

(plane) is perpendicular to (plane) is perpendicular to the buckythe bucky

Beam – perpendicular & to Beam – perpendicular & to pass through the orbitpass through the orbit

Optic foramen – PA obliqueOptic foramen – PA oblique

Head in PA position related to the buckyHead in PA position related to the buckyPosition the head so that The Nose, Position the head so that The Nose,

Cheek and Chin of the side being Cheek and Chin of the side being examined is in contact with the buckyexamined is in contact with the bucky

Orbit in center of the buckyOrbit in center of the buckyMedian sagital plane 55Median sagital plane 5500 to bucky to buckyThe base line (plane) is at 55The base line (plane) is at 5500 to the bucky to the buckyBeam – perpendicular & to pass through Beam – perpendicular & to pass through

the orbitthe orbit

Optic foramen- Radiographic Optic foramen- Radiographic appearanceappearance

CriteriaCriteria Optic foramen Optic foramen

visible at the end visible at the end of the sphenoid of the sphenoid ridge in inferior ridge in inferior and lateral and lateral quadrant of the quadrant of the orbit.orbit.

Optic foramenOptic foramen