ORBITS

RT 233

Parieto-acanthial (Waters) projection Modified Parieto-acanthial (shallow Waters)

projection PA Axial (Caldwell) projection Lateral projection Acanthio-parietal (reverse Waters) projection Modified Acanthio-parietal(reverse shallow Waters)

projection Submentovertex for Zygomatic Arches Submentovertex Tangential for Zygomatic Arches Modified AP Axial (Townes) for Zygomatic Arches

Posterior view of facial bones

BONES THAT MAKE UP THE ORBIT

Frontal Sphenoid Ethmoid Maxillary Lacrimal Palatine Zygoma

Circumference of orbits 3 bones

Frontal bone Maxiilla Zygoma

Interior of orbits 4 bones

Ethmoid Sphenoid Palatine Lacrimal

7

1. Roof Primarily

composed of orbital plate of frontal bone

2. Floor Zygoma (small

amount) Maxilla Palatine

3. Two Walls Medial

Lacrimal Very thin and

delicate

Lateral Zygoma (large

amount) Thickest wall

8

1. Optic Foramen Optic canal Sphenoid strut

2. Superior Orbital Fissure

3. Inferior Orbital Fissure

Lateral view of the lateral orbital wall and its relationships. Key: FZS, frontozygomatic suture; FPZ, frontal process of the zygoma; ZB, zygomatic bone; ZA, zygomatic arch; ZFF, zygomaticofacial foramen; ZTF, zygomaticotemporal foramen; IOF, inferior orbital fissure; MS, maxillary sinus; TB, temporal bone; FB, frontal bone; GWS, greater wing of sphenoid.

11

1. Each orbit projects 30 degrees superiorly 37 degrees toward MSP

CTCTMRIMRIUltrasoundUltrasoundPlain filmPlain filmAngiographyAngiography

Methods of imaging:

Indications for imaging:

Possible FracturesPossible Fractures BlowoutBlowout TripodTripod LefortLefort

Foreign body of the eyeForeign body of the eye

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1. Orbits

1. Basic Parietoorbital

(Rhese Method) Parietoacanthial

(Waters method)

1. Special Modified

Parietoacanthial (Modified Waters method)

PA Caldwell, (exag)

1. Eyes

1. Basic Lateral

PA Axial

Modified Parietoacanthial (Modified Waters method)

Rhese positioning

Waters orbital rims, zygoma, inferior orbital foramenModified Waters (Shallow) inferior orbital rim in profile, Acanthioparietal same as Waters but magnifiedRhese optic foramenPA Axial Caldwell superior sphenoid fissure

Lateral Eye foreign body, soft tissueWaters foreign body, soft tissueModified Waters foreign body, soft tissuePA Axial foreign body, soft tissue