CH.11 positioning skull

lateral skull

MSP of head is parallel to IR

IPL is perpendicular to IR

IOML is parallel to IR

enters 2 inches superior to EAM

10× 12 CW

evaluation criteria for lateral skull

superimposed orbital roofs and greater wings of sphenoid

superimposed mastoid regions and EAM

superimposed TMJs

sella turcica in profile

entire cranium without rotation or tilt

PA axial / caldwell method of the skull

forehead and nose resting on table or upright bucky

OML perpendicular to IR

IR centered to nasion

10×12 LW

15 degrees caudad angle

PA axial/ caldwell method of the skull criteria

entire cranium without rotation or tilt

demonstrates petrous pyramids in lower third of orbit

AP Axial/ Towne method

flex the patient’s neck enough to place either OML or IOML perpendicular to IR

CR enters 2.5 inches above the glabella passing through the level of the EAM

30, 37

for the Towne method the OML is degrees caudal and the IOML is _ degrees caudal

AP axial/ Towne method evaluation cirteria

symmetric petrous pyramids

occipital bone is shown

dorsum sellae and posterior clinoid process visible within foramen magnum

SMV projection/ Schuller method

seated supright

extend neck placing IOML parallel with IR and perpendicular to the floor

CR is through sella turcica perpendicular to IOML

enters MSP of throat between angles of mandible

passes through a point ¾ inch anterior to level of EAM

SMV projection/ Schuller method evaluation criteria

entire cranium without tilt or rotation

IOML parallel to IR

lateral facial bones

Interpupillary line (IPL) perpendicular to IR infraorbitalmeatal line(IOML) parallel to front edge of the edge of the IR

CR enters the lateral surface of zygomatic bone halfway between outer canthus and external acoustic meatus (EAM)

lateral facial bones evaluation criteria

lateral image of the facial bones

all facial bones in entirety with zygomatic bone centered

no tilt or rotation

parietoacanthial waters facial bones

rest head on tip of extended chin

place orbitomeatal line (OML) to form 37-degree angle with place of IR

mentomeatal line (MML) perpendicular to IR

CR is perpendicular to exit acanthion

parietoacanthial waters facial bones evaluation criteria

orbits, maxillae, and zygomatic arches

entire orbits and facial bones

no rotation or tilt

petrous ridges projected just below maxillary sinuses

modified parietoacanthial / modified waters

performed with less extension of the patient’s neck

places OML more perpendicular to the IR plane

good to demonstrate blowout fractures

OML adjusted to form a 55 degree angle with the IR

CR is perpendicular to exit acanthion

lateral nasal bones

upright or recumbent

IPL perpendicular to tabletop

IOML parallel

CR perpendicular to bridge of nose and enters at a point 1 inch distal to nasion

lateral nasal bones evaluation criteria

nasal bones and soft tissues of the nose, both sides for comparison

nasal bones, anterior nasal spine, and frontonasal suture

no rotation

PA mandibular Rami

seated upright

patient’s forehead and nose on IR

OML perpendicular to IR

CR is perpendicular to exit acanthion

PA mandibular Rami evaluation criteria

mandibular body and rami shown

TMJ to the tip of the chin

PA Axial mandibular Rami

seated upright

forehead and nose on bucky

CR is 20-25 degrees cephalad

exits acanthion

PA Axial mandibular Rami evaluation criteria

throws the mandible up to elongate it

mandibular body and rami is shown

entire mandible

PA mandibular body

seated upright

patients nose and chin on IR

anterior surface of the mandibular symphysis parallel to IR

AML nearly perpendicular to IR

CR is perpendicular to level of lips

PA mandibular body evaluation criteria

mandibular body (horizontal portion)

entire mandible

no rotation

PA axial mandibular body

seated upright

patients nose and chin on bucky

CR is directed midway between the TMJs at a 30 degree cephalic angle

PA axial mandibular body evaluation criteria

mandibular body and TMJs shown

entire mandible

TMJs just inferior to the mastoid process

no rotation or tilt

axiolateral and axiolateral oblique mandible

seated upright

adjust rotation of head to place area of interest parallel to IR

CR is angled 2o-25 degrees cephalad to pass directly through the mandibular region of interest

true lateral

to see the ramus in a axiolateral and axiolateral oblique mandible the patients head is in a

30 degrees toward IR

to see the body in a axiolateral and axiolateral oblique mandible the patients head is in a

45 degrees toward IR

to see the symphysis in a axiolateral and axiolateral oblique mandible the patients head is in a

axiolateral and axiolateral oblique mandible evaluation criteria

region of the mandible that was parallel to the IR

SMV mandible

upright

neck fully extended

rest head on its vertex

IOML as parallel as possible with the IR and perpendicular to the floor

CR is perpendicular to IOML

SMV mandible evaluation criteria

coronoid and condyloid process of the rami

condyles of mandible anterior to par petrosal

AP Axial TMJs

seated upright

flex neck to place OML perpendicular to IR'

CR is angled 35 degrees caudad

centered halfway between TMJs entering a point 3 inches above nasion

one exposure with closed mouth and one with open mouth

AP Axial TMJs evaluation criteria

mandibular condyles and fossae of the temporal bones

Axiolateral TMJs (Schuller)

seated

center a point 0.5 inches anterior to the EAM to IR and anterior 2 inches to the EAM

head in lateral position

IPL perpendicular to IR

CR is angled 25 or 30 degrees caudad

one open mouth and one closed mouth

Axiolateral TMJs (Schuller) evaluation criteria

TMJs with mouth open and closed

both sides for comparison

TMJ anterior to the EAM

Axiolateral oblique TMJs/ modified laws

seated upright

one with open and one with closed mouth

center a point ½ inch anterior to EAM

rest cheek against grid

rotate MSP of head 15 degrees toward IR

IPL perpendicular to IR

CR angled 15 degrees caudad, exits through TMJs closer to IR, enters approximately 1 ½ inch superior to upside EAM

Axiolateral oblique TMJs/ modified laws evaluation criteria

condyles and necks of the mandible are shown

open mouth: mandibular fossa and inferior and anterior excursion of the condyle

closed mouth: fractures of the neck and condyle of the ramus

TMJ articulation

lateral sinus

seated erect

head in true lateral

interpupillary line (IPL) perpendicular to IR

CR is horizontal and perpendicular to IR, enters 1 inch posterior to outer canthus

isolates and puts all the sinuses in profile

lateral sinus evaluation criteria

all four sinuses

sphenoidal sinuses best demonstrated

PA axial / caldwell sinus

seated upright

extend neck to rest the tip of the nose on the IR

OML is 15 degree angle to horizontal CR

CR exits nasion, 15 degree relationship between the CR and the OML

PA axial / caldwell sinus evaluation criteria

frontal sinuses superior to frontonasal suture'

anterior ethmoid air cells

sphenoid sinuses seen through nasal fossa

petrous pyramids in lower third of orbits

primarly demonstrates the frontal sinuses and anterior ethmoidal air cells

parietoacanthial projection/ waters method sinuses

seated erect

rest chin on vertical IR

hyperextend neck to place OML at 37 degree angle from IR plane

MSP and mentomeatal line (MML) perpendicular to IR

CR is horizontal and exits acanthion

parietoacanthial projection/ waters method sinuses evaluation criteria

maxillary sinuses

petrous pyramids lying inferior to maxillary floor

frontal and ethmoid sinuses are distorted

OML in proper position

parietoacanthial projection/ open- mouth waters method sinuses

seated erect

rest patients chin on IR

hyperextend neck to place OML 37 degree angle from IR

open mouth wide while holding position

CR is horizontal and exits acanthion

parietoacanthial projection/ open- mouth waters method sinuses evaluation criteria

sphenoidal sinuses projected through open mouth

maxillary sinuses shown

SMV sinuses

upright

hyperextend neck and rest vertex of head on IR

neck extended to place IOML parallel to IR

CR is horizontal and perpendicular to IOML, enters MSP ¾ inches anterior to level of external acoustic meatus (EAM)

SMV sinuses evaluation criteria

sphenoid sinus shown

ethmoid air cells shown

mandibular condyles anterior to petrous pyramids

lateral orbit evaluation criteria

entire orbits both left and right

localization of foreign bodies

superimposed orbital roofs

PA axial orbit evaluation criteria

30 caudad

entire orbits, orbital rims side by side in its entirety (left and right)

parietoacanthial/ modified waters for orbit

shows the tripod fracture and the blowout fracture

reese orbit

nose and cheek on IR

patient in a 53 degree rotation

no tube angle

exit of orbit of interest