Advanced craniofacial Flashcards
What bones are involved in the formation of the orbit?
7 bones in total 3 Cranial -Frontal -Sphenoid -Ethmoid 4 Facial -Maxilla -Zygoma -Lacrimal -Palatine
Orbits: Clinical Indications
- Fractures
- Foreign bodies
Lateral Orbits: Technical factors
SID:
40inches
IR:
8X10in; Landscape;
Exposure factors
-8 mAs; 70 kV
Lateral Orbits: positioning and CR
- Patient is erect or recumbent
- True lateral
- MSP II to IR
- IPL perpendicular to IR
- IOML baseline
CR
- perpendicular to IR; directed to the outer cantheus
Lateral Orbits: Evaluation criteria
-Superimposed
orbital roofs
-Optimal density
Orbits Modified Caldwell (occipitofrontal) : technical factors
SID:
40in
IR:
8X10in
Exposure factors
70kV; 20mAs
Orbits mod. Caldwell: positioning and CR
positioning
- Patient is prone or erect
- OML perpendicular to IR
CR
-angled 30 degrees caudad
directed to exit at the nasion
orbits Mod. Caldwell: evaluation criteria
- petrous ridges projected below the inferior orbital margin
- entire orbit visualized
- no rotation as evident by the equidistance between the outer canthus and lateral aspect of the skull on both sides
- no tilt as evident by the orbits within the same horizontal plane
Orbits waters (mod. parieoacanthial): technical factors
SID:
40in
IR:
8X10in
Orbit Waters: positioning and CR
- The patient is prone or erect
- OML forms a 55 degree angle with IR
- LML perpendicular to IR
CR
perpendicular to IR; exit at acanthion
Waters Obrits: Evaluation Criteria
-Petrous ridges below orbital rims -Less distorted view of orbits -No rotation or tilt as evident by outer canthus to lateral border of skull + inferior margin of orbits
QEII routine for Orbits
Waters + lateral
Mandible: Clinical Indications
Fractures
Tumors
AP/PA Mandible: technical Factors
SID:
40in
IR:
10X12in
Exposure Factors
10-12.5mAs; 70kV
AP/PA Mandible: positioning and CR
positioning
-erect or supine (traumas done supine)
CR
perpendicular to IR to exit at the junction of the lips
AP/PA Mandible: Rami baseline
OML is perpendicular to the IR for Rami evaulation
AP/PA Mandible: Body baseline
The AML is perpendicular to the IR to evaluate the body
AP/PA Mandible: Evaluation criteria
-Rami and lateral portion of body visualized
-Midbody and mentum
faintly visualized,
superimposed on c-spine
-No rotation (symmetrical)
PA Axial Mandible: Technical Factors
SID
40in
IR
10X12; portrait; grid
Exposure Factors
16mAs; 70-80kV
PA axial Mandible: positioning, baseline and CR
Positioning
- erect or prone
baseline: OML perpendicular to IR
CR
20-25 degree cephallic angle; directed to exit at the acathion
PA Axial Mandible: Evaluation Criteria
-TMJs and heads of condyles visible through mastoid processes -Condyloid processes well visualized and slightly elongated -Midbody and mentum faintly visualized, superimposed on c-spine -No rotation (symmetrical)
AP axial (Towne method): technical factors
SID
40in
IR
10X12in; Portrait; grid
Exposure Factors
16mAs; 70-80kV
AP Axial Mandible: positioning, baseline and CR
position
- erect or supine
Baseline
- OML perpendicular to IR
CR
35-42 degrees caudal (*40 degrees if temporomandibular fossae are area of intrest); Directed 1in superior to the glabella
AP Axial Mandible: Eval. criteria
-Condyloid processes and TM fossae visualized -Minimal superimposition of TM fossae and mastoids -No rotation (symmetrical)
Mandible- Axiolateral Obliques: technical factors
SID
40in
IR
10X12in; Portrait; grid
Exposure factors
8mAs; 70kV
*both sides are imaged
Mandible- Axiolateral Obliques: Positioning and CR for General Survey/ Rami
Positioning
- erect or supine
- rotate patients head 10-15 degrees from true lateral
head tilted 25 degrees towards IR
CR
- perpendicular to IR ( 25 degrees if head tilt not possible achieve 25-degree angle with cephallic angle)
- directed to the area of intrest
Mandible- Axiolateral Oblique: Positioning and CR for the Body
positioning
- rotate patients head 30 degrees toward the IR from a true lateral
- tilt patients head 25 degrees towards IR
CR
- perpendicular to IR ( 25 degrees if head tilt not possible achieve 25-degree angle with cephallic angle)
- directed to the area of intrest
Mandible- Axiolateral Obliques: positioning and CR for Mentum
Positoning
- rotate patients head 45 degrees towards the IR from true lateral
- tilt patients head 25 degrees towards the IR
CR
- perpendicular to IR ( 25 degrees if head tilt not possible achieve 25-degree angle with cephallic angle)
- directed to the area of intrest
Mandible- Axiolateral Oblique: Evaluation Criteria
-Side closest to IR visualized
-No superimposition of area of interest from
opposite side of mandible
-Area of interest visualized with minimal
foreshortening
-No superimposition of rami by c-spine
Mandible QEII routine
PA
- AML baseline for body
- OML baseline for rami
Axiolateral obliques
- right and left
- dependent on area of intrest
Mandible- Pantomography positioning
- Ensure patient is standing straight with OML parallel to the floor
- Position bite block between patient’s front teeth
- Instruct patient to place lips together and position tongue on roof of mouth
- Occlusal plane declines 10 from posterior to anterior
Mandible- Pantomography: evaluation criteria
Single image of the teeth, mandible, and TMJs
Correct positioning indicated by:
-Symphysis projected slightly below mandibular angles
-Mandible oval in shape
-Occlusal plane parallel with long axis of image
-Upper and lower teeth slightly apart – no superimposition
No rotation or tilt evidenced by:
-TMJs on same horizontal plane
-Rami and posterior teeth equally magnified
-Anterior and posterior teeth sharply visualized with
uniform magnification
Temporomandibular Joints: Clinical Indications
Indications
- Fractures
- ROM assessment
TMJs- AP Axial (Mod. Townes) : technical factors
SID
40in
IR
8X10in; portrait
Exposure Factors
16mAs; 70-80kV
TMJs AP Axial: Position, baseline and Central Ray
position
-patient erect or supine
Baseline
OML is perpendicular to IR
CR
35 degrees caudal (42 degrees caudal if using IOML); directed to 3 inches superior to the nasion
TMJs AP Axial: Evaluation Criteria
-Condyloid processes and TM fossae
demonstrated
-No rotation
(symmetrical)
TMJs- Axiolateral Open/ Closed mouth: Technical Factors
SID
40 inches
IR
8X10in; portrait
Exposure Factors
16mAs ; 70-80kV
TMJs- Axiolateral Open/Closed Mouth: position and Central Ray
position
- erect or prone
- Head in a true lateral
- TMJ against IR is centered (and imaged)
CR
-25-30 degrees caudal directed 0.5in anterior and 2in superior to upside EAM
TMJs- Axiolateral Open/Closed Mouth: Evaluation Criteria
-Close collimation!
-Images marked
correctly
-TMJ closest to IR is
visualized without
superimposition by opposition TMJ
-TMJ of interest not
superimposed by c-spine
TMJs QEII routine
Axiolateral open/closed mouth (bilateral)
TMJD
Temporomandibular joint dysfunction -pain in the jaw joint and surrounding tissues and limitation in jaw movements.
Causes
- autoimmune diseases
- infections
- injuries to the jaw area
- dental procedures
- Arthritis
Zygomatic Arches: Clinical Indications
- trauma
- fractures
Zygomatic Arches- frontooccipital (AP Axial): technical factors
SID
40in
IR
10X12 in; Portrait
Exposure Factors
8 mAs; 70kV
Le Fort fractures
French surgeon who investigated facial
fractures by inflicting various types of trauma on
cadaver skulls
Published his findings in 1901
Le Fort Fractures I
-horizontal maxillary fracture, separating the teeth from the upper face.
-fracture line passes through the alveolar ridge,
lateral nose and inferior wall of maxillary sinus
Le Fort Fractures II
-pyramidal fracture, with the teeth at the pyramid
base, and nasofrontal suture at its apex
-fracture arch passes through posterior alveolar
ridge, lateral walls of maxillary sinuses, inferior
orbital rim and nasal bones
Le Fort III
-craniofacial disjunction
-fracture line passes through nasofrontal suture,
maxillo-frontal suture, orbital wall and zygomatic
arch.
Zygomatic Arches- AP Axial: Position, baseline and CR
position
- pt. is erect or recumbent
Baseline
OML perpendicular to IR
CR
Angled 30 degrees caudal, directed 1in superior to the nasion to pass through the zygoma
Zygomatic Arches- AP Axial: Evaluation Criteria
- Arches seen without rotation or superimposition
- close collimation
Zygomatic Arches- parietoacanthial: technical Factors
SID
40in
IR
10X12in; portrait; grid
Exposure Factors
70kV; 10-12.5 mAs
Zygomatic Arches- Submentovertex (SMV): technical factors
SID
40in
IR
10X12in; portrait
Exposure Factors
8-10mAs; 70kV
Zygomatic Arches- SMV: position and CR
position
-have pt. lift chin and hyperextend their neck IOML parallel to IR
CR
perpendicular to IR, directed 4cm inferior to mentum
Zygomatic Arches- SMV: Evaluation Criteria
-Both zygomatic arches demonstrated laterally
from each ramus
-No rotation
-Close collimation
Zygomatic Arches- Inferosuperior Tangential: Techincal Factors
SID
40
IR
10X12in; Portrait
Exposure factors
8mAs; 70kV
Zygomatic Arches- inferosuperior tangential : position, baseline and CR
position
- patient is erect (sitting)
- have patient lift chin and hyperextend their neck
- IOML perpendicular to IR
- rotate patients head and tilt chin 15 degrees towards side to be exaimined
CR
-perpendicular to IR directed to Zygomatic arch of intrest
Zygomatic Arches- Inferosuperior tangential: evaluation criteria
- Zygomatic arch without superimposition
- close collimation
Blowout Fracture
A break in one or more the orbital bones. Indicated by a ‘Brow sign’
Tripod Fracture
Effects the:
- zygomatic arch.
- inferior orbital rim, and anterior and posterior maxillary sinus walls.
- lateral orbital rim.
