Transcript Anatomy Of Zygomatic Arches

RT 233 Skull Radiography
introducing
Zygomatic Arches
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_bones#/videos
Zygomatic Arches
Anatomy of
Zygomatic
Arches
Essential
Projections
Pathology of
Zygomatic
Arches
This is just getting more and more fun ! ! !
Anatomy of Zygomatic
Arches
Bones Involved, anatomical landmarks
Anatomy of Zygomatic Arches
The squamous portion of the
temporal bone is the thin
upper portion. It forms a part
of the side of the cranium
and has a prominent arched
process called the zygomatic
process. The zygomatic
process projects anteriorly
articulating with the
zygomatic facial bone, this
completes the zygomatic
arch.
On the inferior border of the
zygomatic process is the
rounded eminence called the
articular tubercle. The
articular tubercle forms the
anterior boundary of the
mandibular fossae.
The mandibular fossa
receives the condyle of the
mandible to form .
Anatomy of Zygomatic Articulations
1) zygomatic processtemporal bone
2) Mandibular condyle
3) Articular tubercle
4) zygomatico-temporal
sutures
5) zygoma
Possible Indications for Zygomatic Arch Imaging
1.
2.
3.
4.
5.
6.
Car accident
Sports injury
Domestic violence, child or elder abuse
Blunt trauma
Fall
Gunshot
Essential Projections
SMV, Tangential, modified Townes
Essential Projections: Zygomatic Arches
Submentovertical (SMV)
Tangential
Anteroposterior (AP) axial (modified
Towne)
Submentovertical Zygomatic Arches
• Patient position
– Seated upright or supine
– If supine, elevate thorax
• Part position
– Hyperextend neck to place IOML parallel with IR
plane (as much as possible)
– Rest head on vertex
– MSP perpendicular to IR plane
Submentovertical Zygomatic Arches
• CR
– Perpendicular to IOML
– Enters MSP of throat at level 1 inch (2.5 cm)
posterior to outer canthi
– Center IR and CR
• Collimated field
– 8 x 10 inches (18 x 24 cm)
SMV
SMV
SMV projection
Tangential Zygomatic Arches
• Patient position
– Seated upright with back against vertical Bucky
– Supine with trunk elevated
Tangential Zygomatic Arches
• Part position
– Hyperextend neck and rest head on vertex
– IOML as parallel with IR plane as possible
– Rotate MSP of head 15 degrees toward side being
examined
– Tilt top of head 15 degrees away from side being
examined
– Center zygomatic arch to IR
Tangential Zygomatic Arches
CR
Perpendicular to IOML
Centered to zygomatic arch at a point 1 inch (2.5
cm) posterior to outer canthus
Centered to IR
Collimated field
8 x 10 inches (18 x 24 cm)
AP Axial (Modified Towne) Zygomatic
Arches
Patient position
Seated upright or supine
Part position
MSP perpendicular to midline of grid
OML perpendicular to IR plane
• May use IOML and increase CR angle to ??°
AP Axial (Modified Towne) Zygomatic
Arches
CR
Angled 30 degrees caudad to enter glabella
approximately 1 inch (2.5 cm) above nasion
If IOML used, angle 37 degrees caudad
Center IR and CR
Collimated field
8 x 10 inches (18 x 24 cm)
Exciting new transitions
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seeing?
beautiful images you’ve been
It’s up to you.
Pathology of Zygomatic
Arches
LeFort Fractures, Tripod Fractures,
FRACTURES SITES
TRIPOD FRACTURE
The tripod fracture, also called the zygomaticomaxillary complex or
malar fracture, is composed of a set of three (actually 4) fractures. The
first portion of the tripod fracture involves the maxillary sinus including
the anterior and postero-lateral walls and the floor of the orbit. The
second portion involves the zygomatic arch. The third portion involves
the lateral orbital rim, usually including the lateral orbital wall, or the
fronto-zygomatic suture. The term is actually not accurate as there is a
fourth suture that can be involved: between the sphenoid and
zygomatic bones.
LeFort Fractures
LeFort Fractures, Type I, Type II
Type III LeFort
___________ Fractures
_____________ Zygomatic Arches
Isolated Zygomatic Arch Fractures
Where is the fracture?
Waters view
What ???
Name this fracture:
Name this fracture:
Name this fracture:
What is the bone just posterior to the
lacrimal bone?
What’s Your Message?
ZYGOMATIC
ARCHES