orbita radiography
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8/12/2019 Orbita Radiography
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Radiography of the Orbits
Fall 2009
FINAL
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Function of Orbits
1. Serve as bony sockets for the eyeballs
2. Openings for nerves and blood vessels
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Division of the Orbits1. ________________
– Primarily composedof orbital plate of
frontal bone
2. ________________
– Zygoma (small
amount)
– Maxilla – Palatine
3. _______________
– Medial
• Lacrimal
– Lateral• Zygoma (large
amount)
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Base of the OrbitThe circumference is
made of 3 bones:
1. _________________
2. _________________
3. _________________
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Openings in Posterior Orbit
1. ______________ – Optic canal
– Sphenoid strut
2. ______________
3. ______________
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ANGLE OF ORBITS
1. Each orbit projects
– 30 degrees superiorly
– 37 degrees toward MSP
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Indications for Orbit and Eye
Radiography
1. Possible Fractures
1. Blowout2. Tripod
3. Lefort
2. Foreign body of the eye
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Mechanisms producing
Orbital Fractures
1. Auto accidents
2. Assault
3. Falls, sports, and industrial accidents
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Blowout Fracture
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Blowout Fracture
1. Blow to the eye
2. Orbital floor is fractured
3. Soft tissue herniates
into maxillary sinuses
4. Often have ocular injury
Ponsell, 2003
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Blowout Fracture
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______________________
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Tripod Fracture
1. Direct blow tozygoma
2. Visual concaveabnormalities
3. Usually orbits are
involved
4. Free floating zygoma
Ponsell, 2003
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LeFort
Fractures
LeFort types II & IIIinvolve the orbits
Richardson, 2000
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Lefort II and III
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LeFort Fractures
1. Type II
1. Separation through: frontal processes
lacrimal bones
orbit floors,
zygomaticomaxillarysuture line
lateral wall of
maxillary sinuses
pterygoid
1. Complications
1. ____________
system obstruction
2. Infraorbital nerve
anesthesia
3. ____________
4. Malocclusion
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Lefort 2
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LeFort Fractures
1. Type III
1. Separation of mid third of
face at:
zygomaticotemporal naso-frontal sutures
and across orbital floors
1. Complications
1. _________________
2. Mal-union
3. _________________
4. Lenthening of mid face
5. _________________
system obstruction
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LEFORT 3
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LEFORT 3
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Basic and Special Projections
1. Orbits
1. Basic• _________________
• _________________
2. Special• _________________
1. Eyes
1. Basic
• _______________
• _______________
• _______________
P i t thi l P j ti
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Parietoacanthial Projection
Waters Method
1. Positioning
1. ____________
2. ____________
2. Lines and planes:
1. ____________
2. ____________
3. CR:
1. ___________
Ballinger & Frank, 1999, pg 317
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Parietoacanthial Projection
Waters Method Radiograph
1. Distance from lateral
border of skull and
orbit equal on each
side
2. Petrous ridgesprojected
immediately below
maxillary sinuses
P i t thi l P j ti
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Parietoacanthial Projection
Modified Waters
1. Positioning:
1. _____________
2. Lines and planes1. _____________
2. _____________
3. CR
1. ____________
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Modified Waters Radiographs
1. Petrous ridges
projected
immediately below
the inferior border ofthe orbits
2. Equal distance from
lateral orbit to lateral
skull on both sides
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Modified Parietoacanthial
Modified Waters method
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Modified Waters
Radiograph & Diagram
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Acanthioparietal Projection
Reverse Waters Method
1. Positioning
_______________
2. Lines and planes
_______________ _______________
3. CR
_______________
Ballinger & Frank, 1999, pg 320
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Reverse Waters Radiograph
1. Distance from lateral
border of skull and
orbit equal on each
side
2. Petrous ridgesprojected
immediately below
maxillary sinuses
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Parietoorbital Projection (Rhese Method)
(PA) Optic Canal and Foramen Radiograph
1. Optic canal & foramen visibleat end of sphenoid ridge ininferior & lateral quadrant oforbit
2. Entire orbital rim
3. Supraorbital margins lying insame horizontal plane
4. Close beam restriction to theorbital region
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Rhese Diagram and Radiograph
Rh M th d
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Rhese Method
(AP) Optic Canal and Foramen1. Positioning:
1. _______________
2. _______________
2. Lines and planes:1. _______________
2. _______________
3. AP- CR:
1. _______________
Ballinger & Frank, 1999, pg 292
Rhese Method
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Rhese Method
(AP) Optic Canal and Foramen
Radiograph1. Optic canal & foramen visible
at end of sphenoid ridge ininferior & lateral quadrant oforbit
2. Entire orbital rim
3. Supraorbital margins lying insame horizontal plane
4. Close beam restriction topthe orbital region
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Rhese Radiograph and Diagram
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Foreign objects in the EYE
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Lateral Eye for Foreign Body
1. Density & contrastpermitting optimalvisibility of orbit andforeign bodies
2. SI orbital roofs
3. Close beamrestriction
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PA Axial (EYE)1. Positioning
1. Forehead & nose onIR.
2. Center IR ¾ “ distalto nasion
3. ________________
2. Lines and planes:1. ________________
3. CR:
1. Through center oforbits, 30 degreescaudal
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PA Axial Eye Radiograph
1. Petrous pyramidslying below orbitalshadows
2. No rotation ofcranium
3. Close beamrestriction
Modified Waters
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Modified Waters
(EYE)1. Positioning:
1. IR at level of orbits
2. Rest pt’s chin on IR
3. Instruct pt to close eyes
and hold eyes still
2. Lines and planes:
1. MSP perp
2. OML 50 degrees
3. CR:
1. Perp through mid-orbits
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LETS REVIEW
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Seven Bones of the Orbit
O i d S ti
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Openings and Supporting
Structures of Openings of the Orbit
Parietoorbital Oblique Projection of
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Parietoorbital Oblique Projection ofOrbits
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References
Ballinger, P.W. & Frank, E.D. (1999).
Merrill’s atlas of radiographic positions and radiologicprocedures. V2. New York: Mosby
Ponsell, M.R. (2003). Assessing facial fractures in theemergency room. New Jersey
Richardson, M.L. (2000). Facial and mandibular fractures.
Retrieved May 5, 2007 from:http//www.rad.washington.edu/mskbook/facialfx.html
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