RADT 1522 Orbits, Facial Bones and Nasal Bones Wynn Harrison, MEd

Facial Anatomy  14 facial bones (How Many of Each) –Maxilla - Vomer –Zygomatic - Mandible –Palatine –Nasal –Lacrimal –Inferior Nasal Conchae

Mid-saggital view

New Words  Blow-Out Fracture – Impact fracture (Trauma) of the orbital floor resulting in orbital intrusion into the maxillary sinus. *** Look at the orbits carefully, since % of all facial fractures involve the orbit in some way % of all facial fractures involve the orbit in some way

 Le Fort I - tooth bearing portion separated from upper maxilla  Le Fort II - fracture across orbital floor and nasal bridge (pyramidal fracture)  Le Fort III - fracture across frontozygomatic suture line, entire orbit and nasal bridge (craniofacial separation)

 LeFort Type I  LeFort Type II  LeFort Type III

 Tripod Fracture – A fracture in which the zygoma is separated from its attachment to the maxilla, frontal and temporal bones

 Bell’s Palsy - Bell's palsy is a weakness or paralysis of the muscles that control expression on one side of your face.

Orbits  Rhese View- Midsagittal plane forms a 53 degree angle with IR. Chin, cheek and nose on the table (three- point landing!) Acanthiomeatal line perpendicular to IR. Optic foramen should be seen in center of image.

Foreign Body  PA and Lateral views are performed to look for foreign body in the orbit.  What do you think you need to have them do differently for this exam?  Look UP, Look Down

Nasolacrimal System Injection Site Lateral image post injection

Facial Bones Imaging Caldwell or PA image LateralWaters

Radiographic Views PA (Caldwell)  Tuck patient’s chin; nose and forehead on table/wall bucky  OML perpendicular to IR  15 degree caudal angulation  Petrous pyramids BELOW inferior orbital margin

Caldwell (use horizontal ray)

Caldwell for facial bones

PA (Caldwell) Calcified meningioma

 Lateral – External auditory meatus externally and mandible inferiorly with supracillary arch superiorly in view.  CR centered to zygoma, midway between outer canthus and EAM  Midsagittal plane is parallel to IR  IPL is perpendicular to IR

Lateral facial bones

What ‘Bout Technique!!!  Would you increase or decrease technique for lateral facial bones compared to a lateral skull?

Water’s View  Midsagittal plane perpendicular to IR  IPL parallel to IR  OML makes 37 degree angle with IR  COLLIMATE!!!!

Waters for facial bones

Modified Parietoacanthial (Modified Waters)  OML 55 degrees to the IR  Chin and nose on table  Petrous pyramids are seen mid- maxillary sinus  CR exits acanthion  See pg. 355 (Merrill’s 12 th Edition)

Reverse Water’s View  Used when patient cannot be placed in prone position.  Mentalmeatal line perpendicular to IR  CR perpendicular; enters acanthion  CR parallel to acanthiomeatal line  Merrill’s pg (12 th Ed)

Nasal Bones Lateral and Superior/Inferior Views  Lateral: Position exactly like you would for a lateral skull … CR ½ inch inferior to nasion.  CR Perpendicular to IR  COLLIMATE

Hyper extended waters

Axial Nasal Bones  Use occlusal film. Patient holds film in teeth. NOT DONE ANYMORE.  Use occlusal film. Patient holds film in teeth. NOT DONE ANYMORE.  CR perpendicular to film CR

Zygomatic Arches

Bilateral Arches - SMV  IOML parallel to IR and perpendicular to CR  CR midsaggital and collimate to outer edges of zygoma

fracture

Oblique Tangential  Same position as SMV except head tilt 15 degrees toward side of interest (Merrill’s p ed)

May View (tangential)  PA positioning; IOML perpendicular to CR, head tilt 15 degrees away from the area of interest.  CR bisects zygomatic arch Shows single zygomatic arch, free of superimposition  (P , 12 Ed. Merrill’s )

Unilateral arch view

C-arm tangential image