Facial Bones & Orbits
Facial Bones (how many, name them)
Fourteen: two nasal two lacrimal two maxillary two zygoma two palatine two inferior nasal concha one vomer one mandible
Orbit Bones (how many, name them)
Seven (three cranial & four facial): - rim - frontal - forms roof maxilla - floor of orbit zygoma - lateral wall of orbit - apex - lacrimal - tear duct, just posterior on medial wall sphenoid / ethmoid - forms posterior cone of orbit palatine - very tip of apex (little/tiny)
Lateral Nasal Bones
-CR enters 1/2" distal to nasion -CR angle - perp to IR -MSP & IOML parallel w/top of film -IPL perp to IR -AOI: collimate from glabella to upper lip
Submentovertical (SMV) Zygomatic Arches
-CR enters MSP of the throat approx 1" posterior to the outer canthus -Pt vertex on film -CR angle - perp to IOML -IOML parallel to film -MSP perp to IR -AOI: both zygomatic arches
AP Axial Zygomatic Arches (Modified Towne)
-CR enters glabella -CR angle - 30 degrees caudal or 37 degrees for IOML -MSP & OML (or IOML if pt c/n flex neck) perp to film AOI: elongated arches
Lateral Facial Bones Projection
-CR enters lateral surface of the zygomatic bone 1/2 way btwn the outer canthus & the EAM -CR angle - perp to IR -MSP & IOML parallel w/top of film -IPL perp to film -AOI: all facial bones
Lateral Orbits
-CR enters outer canthus -CR angle - perp to IR -MSP parallel to film -IPL perp to IR -AOI: orbits superimposed
PA Axial Facial Bones (Caldwell)
-CR exits nasion -Pt nose and forehead on film -CR angle - 15 degrees caudal -MSP & OML perp to IR -AOI: petrous ridges bottom 1/3 of orbit
Parietoacanthial Facial Bones (Waters)
-CR exits the acanthion -CR angle - perp to IR -OML forms a 37 degree angle w/film -MSP & MML perp to IR -AOI: petrous ridges below maxilla
Parietoacanthial Orbits (Modified Waters)
-Pt chin on bucky -CR enters mid orbits -CR angle - perp to IR -OML forms a 50 degree angle w/film -MSP perp to IR -AOI: petrous ridges are below orbits
PA Axial Orbits
-Pt nose and forehead on bucky -CR exits the inferior margin of the orbit -CR angle - 30 degree caudal -OML perp to IR ***Note different angle -AOI: superior orbital fissure
Orbitoparietal Oblique Orbit (Rhese)
-Pt seated or supine, head rotated so the MSP forms a 53 degree angle to the IR -AML adjusted so it is perp to IR (turn so the eyelashes just show on IR) chin up -CR angle - perp to film -CR enters the uppermost orbit at its inferior & lateral quadrant -AOI: orbit farthest from IR -mark side up
Tangential Zygomatic Arches
-Pt's head rotated 15 degrees twds affected side and top of head 15 degrees away to put affected side twds IR -CR enters zygomatic arch -CR angle - perp to IR -IOML parallel to film -MSP forms a 15 degree angle -AOI: one zygomatic arch (closest to film)
Parietoorbital Oblique Orbit (Rhese)
-Pt's nose, zygoma (cheek) & chin on bucky (three point landing) -CR enters approx 1" superior and posterior to the upside TEA & exits the orbit closest to the film -CR angle - perp to film -MSP forms a 53 degree angle w/film -AML perp to IR -mark side down -AOI: optic foramen must be in the lower, lateral quadrant of the orbit