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Radiographic Technique 2
RAD 1204
A . Tahani Ahmed AL-Hozeam
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TECHNICAL ASPECTS
Sitting erect positions are preferred to exclude any air-fluid levels within the cranial cavities or sinuses.
Patient comfort and skull immobilization are necessary.
Exposure factors range between 75 kVp and 85 kVp. A small focus is to be used with short times and
high mA.
A high lattice grid (40 lines/inch) must be used, FFD=100cm.
Good collimation (Narrow cone for small parts) and non-repeats helps
in minimizing the radiation exposure to the patient.
A contact shield should be used over the neck and chest to reduce the exposure to the thyroid and
female breast in the AP projection.
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SKULL AND CRANIAL BONES
AP Axial (Towne’s projection)
For occipital bone, skull #s, neoplastic processes, and Paget’s disease. ,
foramen magnum .
Film: HD 24x30 cm longthwise .
Remove all metal , plastic ,or other removable objects from patient’s
head. Patient supine, or in erect AP sitting, chin is depressed (OML 90
to film), patients unable to flex neck to IOML perpendicular to the film,
support under head ,no rotation of the head .
CP: 2.5 inches ( 6 cm ) above the glabella .
CR: 30 caudal to OML , OR 37 caudal to IOML .
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B
Lateral Skull (general)
For skull #s, neoplastic processes, and Paget’s disease. Same
indication A horizontal beam is used for trauma cases to show airfluid levels in the sphenoid sinus (a sign of # in the base of skull with
internal bleeding) .
Film: HD 24x30 cm crosswise .
Remove all metal , plastic ,or other removable objects from patient’s
head .Patient in a semiprone , recumbent or erect sitting, head in a
true lateral (required side close to the film), MSP parallel to film, IPL
90 to film.
CP: 5 cm superior to EAM .
CR: 90 to film center .
NB/ patients in recumbent put support placed under the chin to help
in maintaining a true lateral position.
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B
PA Skull (0 Occipital-frontal) projection
For frontal bone,skull #s and neoplastic processes , Paget’s disease.
Film: HD 24x30 cm longthwise .
Remove all metal , plastic ,or other removable objects from patient’s
head . Patient in the erect or prone position. rest patient’s nose and
forehead against the couch center, neck flexed so that OML is 90 to the
film, MSP 90 to film, head not rotated.
CP: Exits the glabella
CR: 90 to film center
NB/ AP is not recommended as it produces 200 times eyes absorbed
dose produced in the PA position.
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B
PA Axial Skull (15 Caldwell) projection
For skull #s, neoplastic processes , paget’s disease .
Film: HD 24x30 cm longthwise .
Remove all metal , plastic ,or other removable objects from patient’s
head . Patient in the erect or prone position. rest patient’s nose and
forehead against the couch center, neck flexed so that OML is 90 to the
film, MSP 90 to film, head not rotated.
CP: Exits the naison.
CR: 15 caudal .
NB/ CR: 25 - 30caudal gives better view of superior orbital fissure
(black arrows) and foramen rotundum and inferior region (white arrows).
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B
Submentovertex (SMV) Skull
For inner temporal bone structures, basal skull #s , occipital
bone, mandible, foramen ovale and foramen magnum, ,
sphenoidal and ethmoid sinuses and mastoid processes.
Film: HD 24x30 cm lengthwise .
Remove all metal , plastic ,or other removable objects from
patient’s head . Patient supine or erect sitting, chin raised,
neck hyperextended till IOML is parallel to film, MSP 90 to
couch top. A pillow under patient’s back allows for sufficient
extension.
CP: Midway between angles of mandible (2 cm anterior to
level of EAMs).
CR: 90 to IOML.
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S
PA Axial Skull (Haas projection )
It shows occipital bone, petrous pyramids, the foramen magnum .
An alternate projection for the Towne’s view if the patient cannot flex
his neck sufficiently for the reverse (counter) Towne projection.
NB/ It is not recommended, however, for the occipital bone because of
the magnification it produces.
Film: HD 24x30 cm lengthwise.
Remove all metal , plastic ,or other removable objects from patient’s
head . Patient in the erect or prone position. rest patient’s nose and
forehead against the couch center, neck flexed so that OML is 90 to the
film, MSP 90 to film, head not rotated.
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CP:
Through level of EAMs
CR:
25 cephalic to OML.
S
AP Axial (Towne’s projection – for AP Sella Turcica)
Detects pituitary adenomas in the sella turcica.
Also shows dorsum sellae, posterior clinoids, the foramen magnum.
Film: HD 18x24 cm lengthwise.
Remove all metal , plastic ,or other removable objects from patient’s
head. Patient supine, or in erect AP sitting, patients flex neck to IOML
perpendicular to the film, MSP 90 to the film .
CP: 4 cm above superciliary arch
CR: 37 caudal (for the dorsum sellae and the posterior clinoids), 30
caudal (for anterior clinoids)
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B
Lateral Skull (for lateral Sella Turcica)
To show pituitary adenomas.
Film: HD 18x24 cm crosswise .
Remove all metal , plastic ,or other removable objects from
patient’s head. Patient in an erect or semiprone .true lateral
position, IPL is 90 to the film , MSP is parallel to the film , IOML is
90 to the film .
CP: 2 cm anterior and 2 cm superior to EAM.
CR: 90 to film center
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B
Facial Bones
PA Axial Skull (15 Caldwell) projection for Facial bones
B
For skull #s, neoplastic / inflammatory processes of the facial bones .
Film: HD 24x30 cm longthwise .
Remove all metal , plastic ,or other removable objects from patient’s
head . Patient in the erect or prone position. rest patient’s nose and
forehead against the couch center, neck flexed so that OML is 90 to the
film, MSP 90 to film, head not rotated.
CP: Exits the naison.
CR: 15 caudal .
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Lateral Skull for facial bones
For fractures, neoplastic or inflammatory processes of facial bones.
Film: HD 18x24 cm lengthwise.
Remove all metal , plastic ,or other removable objects from patient’s
head . Patient in the erect or semi prone position. Head in true lateral
(same position as for lateral skull ), chin adjusted so that both IPL
and IOML are 90 to film , MSP is parallel to film.
CP: Zygoma (midway between the outer canthus and EAM)
CR: 90 to film center
NB/ the facial bone routine commonly includes only a single lateral ,
whereas the skull routine may include bilateral positions.
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B
Lateral Skull (for nasal bones)
For nasal bone fractures both sides for comparison.
Film: HD 18x24 cm detail screen.
Remove all metal , plastic ,or other removable objects from
patient’s head . Patient in the erect or semi prone position. Head in
true lateral , chin adjusted so that both IPL and IOML are 90 to
film, MSP is parallel to the film.
CP: 1.25 cm inferior to naison
CR: 90 to film center
NB/ A long narrow cone should be used.
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B
Superoinferior Tangential (Axial) (nasal bones)
For fractures of the nasal bones.
Film: HD 18x24 cm crosswise detail screen.
Place lead shield over lap or pelvic region to shield gonads.
Patient prone or in the erect sitting end of the chair , chin
extended and rested on cassette, angle support under film,
glabelloalvolar line (GAL) 90 to cassette, long narrow cone used
CP: Naison .
CR: parallel to GAL.
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S
Oblique inferosuperior Tangential (for zygomatic arches) B
For #s, neoplastic, or inflammatory processes of the zygomatic arch.
Both sides are generally taken for comparison.
Film: HD 18x24 longthwise.
Remove all metal , plastic ,or other removable objects from patient’s head
. Patient position is erect or supine. Raise chin, hyperextending neck
,IOML is paralle to the film. Rest head on vertex of skull. head rotated 15
toward side of interest.
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CP:
Zygomatic arch of interest.
CR:
90 to IOML and film.
Parieto-orbital (Rhese View) for optic foramina
For bony abnormalities of the optic foramen. Both sides must
be done for comparison.
Film: HD 18x24 cm
Remove all metal , plastic ,or other removable objects from
patient’s head. Patient semi prone or erect, chin, cheek, and
nose against couch, head needed angle makes 53 with the
couch top, the acanthiomeatal line AML makes 90 to the film,
a long narrow cone should be used.
CP:
Downside orbit (7 cm above and 7 cm behind the up
EAM).
CR:
90 to IOML
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B
PA (or PA Axial) Skull (for mandible )
B
 Best for the body of mandible for #s, inflammatory and
neoplastic processes. PA axial well shows rami and
elongated view of condyloid process.
 Film: HD 18x24 cm longthwise.
 Remove all metal , plastic ,or other removable objects from
patient’s head. Patient prone or erect . Rast patient’s
forhead and nose aginst table, chin tucked so that OML is
90 to film, MSP 90 to the couch top, head not rotated.
 PA ‫ــــ‬CP: exit at junction of the lips
CR: 90 to film center
PA axial ‫ ــــــ‬CP: exit at the acanthion
CR: 20- 25 cephalic
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PA
PA axial
AP Axial (Towne’s projection – for mandible)
For #s, neoplastic or inflammatory processes of the condyloid processes
of the mandible.
Film: HD 18x24 cm longthwise.
Remove all metal , plastic ,or other removable objects from patient’s
head. Patient supine, or in erect , rest patient’s posterior skull in table ,
tuck chin, patients unable to flex neck to IOML perpendicular to the film,
support under head ,no rotation of the head .
CP: Glabella
CR: 35- 40 caudal .
NB/ if patient is unable to bring OML perpendicular to image ,IOML
perpendicular and increase the CR angle 7ْ.
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B
Lateral 25 - 30 (Axiolateral) (for mandible)
For #s, neoplastic, or for inflammatory processes of the mandible
(both sides are done for comparison) .
Film: HD 18x24 cm crosswise
Head in true lateral with MSP parallel to the film, side of interest
placed against the film, mouth closed, extend neck ,head then
rotated in oblique true lateral best (for ramus) 30 best (for the
body), 45 best (for mentum), and 10 - 15 best for a (general
survey).
CP: exit Mandibular region of interest (body, ramus, ….).
CR: 25 cephalic.
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B
Submentovertex (SMV) (for mandible)
For #s, neoplastic, or inflammatory processes of the
mandible.
Film: HD 18x24 cm longthwise.
Remove all metal , plastic ,or other removable objects from
patient’s head. Patient supine or erect sitting, chin raised,
neck hyperextended till IOML is parallel to film, MSP 90 to
couch top. Rest head on vertex of skull. A pillow under
patient’s back allows for sufficient extension.
CP: Midway between angles of mandible
CR: 90 to IOML.
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S
ORTHOPANTOMOGRAPHY (tomography of the mandible)
For #s of the mandible and TM joint pathology.
Film: HD 23x30 cm, or curved non-grid cassette
Tube and film attached at starting position, chin rest raised to same level
as patient’s chin, chin rested on a sterile bite block, patient as close as
possible to the tube stand, chin adjusted until IOML is parallel with the
floor, occlusal plane declines 10 from posterior to anterior, patient’s lips
placed together, tongue on roof of the mouth.
CP:
Fixed CR and FFD. For TMJ, another film must be done with
open mouth.
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S
Lateral 15 (Modified Law for TMJs)
For abnormal range of motion between condyle and TM
fossa.
Film: HD 18x24 cm longthwise.
Patient prone or erect, head in lateral, IPL 90 to film,
IOML 90ْ to the film ,then rotated face15 toward the
film.
CP: 4 cm superior to upside EAM
CR: 15 caudal to pass through the downside TMJ.
NB / one position with open mouth and other with close
mouth.
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S
Paranasal Sinuses, Mastoids, and
Temporal Bone.
PA Skull (Caldwell projection for sinuses )
Good for sinuses (frontal and anterior ethmoidal sinuses). Also
shows other inflammatory conditions (sinusitis, sinus polyps).
Film: HD 18x24 cm lengthwise.
Remove all metal , plastic ,or other removable objects from patient’s
head. Position patient erect .Patient’s nose and forehead against
film, neck extended so that OML is 15 from the horizontal . Support
between forehead and upright bucky .MSP perpendicular to film. No
rotation.
CP: exit at nasion.
CR: 90 horizontal to film .
NB/ why we prefere the erect position?
To image the air-fluid level in sinuses.
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B
Lateral Skull (for sinuses)
For inflammatory conditions( sinusitis, and sinus polyps). (good for
sphenoid, frontal, ethmoid, and maxillary sinuses).
Film: HD 18x24 cm lengthwise.
Remove all metal , plastic ,or other removable objects from patient’s
head. Position patient erect , head in true lateral (IPL 90 to film) ,
IOML perpendicular to the film.
CP: Midway between outer canthus and EAM
CR: 90 horizontal to film center
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B
Parietoacanthial (OM) (Waters View for sinuses )
Best for maxillary and frontal sinuses and nasal fossae. Also shows other
inflammatory conditions ,sinusitis and sinus polyps.
Film: HD 18x24 cm lengthwise.
Remove all metal , plastic ,or other removable objects from patient’s
head. Position patient erect , neck extended, chin and nose against
couch, head adjusted till MML (mentomeatal line) is 90 to the film, OML
makes 37 with film, a long narrow cone should be used.mouth is closed.
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CP:
exit at the acanthion.
CR:
90 horizontal to film center
B
Parietoacanthial (OM) (Open-Mouth Waters for sinuses )
Best for maxillary and frontal sinuses and nasal fossae. Also
shows other inflammatory conditions ,sinusitis and sinus polyps.
Film: HD 18x24 cm lengthwise.
Remove all metal , plastic ,or other removable objects from
patient’s head. Position patient erect , neck extended, chin and
nose against couch, head adjusted till MML (mentomeatal line)
is 90 to the film, OML makes 37 with film but with open mouth
(patient drops his jaw without moving the head). MSP is
prependicular to the film.
CP: exit at the acanthion.
CR: 90 horizontal to film center
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S
Submentovertex (SMV) (for sinuses)
Best for sphenoid ,ethmoid and maxillary sinuses. Also shows other
inflammatory conditions ,sinusitis and sinus polyps.
Film: HD 18x24 cm lengthwise.
Remove all metal , plastic ,or other removable objects from patient’s
head. Position patient erect .chin raised, neck hyperextended till
IOML is parallel to film, MSP 90 to couch top.
CP: Midway between angles of mandible (4 cm inferior to
mandibular symphysis).
CR: 90 to IOML.
NB/ 1-if patient is unable to sufficientiy extend neck ,angle the tube
from horizontal as needed to align the CR perpendicular to IOML.
2- This position is very uncomfortable for patient ,have all factors set
before positioning the patient and complete the projection as quickly
as possible.
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S
Axiolateral Oblique (Modified Law for mastoids)
For bony pathology of mastoids processes. Both sides are
generally exmined for comparion.
Film: HD 18x24 cm lengthwise.
Remove all metal , plastic ,or other removable objects from
patient’s head. Patient semi prone or erect, each auricle taped
forward, head in lateral, then rotated 15 oblique toward the film,
IPL 90 to couch, side of interest down.
CP: Exit downside mastoid tip (2.5 cm posterior, 2.5 cm
superior to upside EAM).
CR: 15 caudal
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B
Axioanterior Oblique (Stenvers for mastoids)
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
For advanced pathology of temporal bone. Both sides are to be
examined for comparison.

Film: HD 18x24 cm lengthwise.

Remove all metal , plastic ,or other removable objects from
patient’s head. Patient semiprone or erect, IOML 90 to film, chin
adjusted so that head is rotated 45 oblique with the couch, side
of interest down, downside mastoid region centered to film.

CP: 7 – 10 cm posterior, and 1.25 cm inferior to upside EAM to
exit through downside mastoid process.

CR: 12 cephalic.
B