Skull postioning

1. POSITIONING OF
SKULL
DR.S.SAJITH MBBS MD RD
DR.SOMERVELL MEMORIAL MEDICAL COLLEGE
RADIOLOGY DEPARTMENT

2. Planes
 Median sagittal plane
 Anthropological plane
 Auricular plane

3. Major body planes used in Skull radiography
Median S agittal Auricular Anthropological

4. The Median Sagittal plane.
 A vertical plane dividing the skull into 2
symmetrical right and left halves when viewed
from the anterior aspect.
The Anthropological plane
 This plane splits the skull into upper and lower
halves passing along the anthropological baselines.
The Auricular plane
 This plane divides the skull into anterior and
posterior compartments along the Auricular lines.

5. Lines
 Inter orbital line
 Infra orbital line
 Anthropological baseline
 Orbito meatal baseline

6. Anthropological Orbital Meatal Interpupillary

7. The Anthropological line
 The Isometric “Baseline” which runs from the
inferior orbital margin to the upper border of the
external auditory meatus (EAM)
The Orbital-Meatal Line
 The original “Baseline” which runs from the outer
canthus of the eye to the centre of the external
auditory meatus
The Interpupillary line
 The line connects the centres of the orbits and is at
90 degree to the median sagittal plane.
NOTE: there is a difference of 10 to 15 degrees
between the Orbital-Meatal line and the
anthropological line.

8. Basic views
 Lateral view
 Fronto occipital view ( A P view )
 Fronto occipital with 30 deg caudad ( TOWNE’S
view)
 Occipito frontal view ( P A view)
 Occipito frontal with 15 deg caudad ( CALDWELL’S
view )
 Submento vertical view (BASILAR view)
 Occipito mental view ( WATER’S view)

9. Lateral view
Position of patient :
 Patient sits facing the bucky and the head is
then rotated, such that the median sagittal
plane is parallel to bucky and inter orbital line
is perpendicular to it.
 Position the cassette transversely in the erect
bucky, such that its upper border is 5 cm
above the vertex of the skull

11. Central ray :
 midway between the glabella and the external
occipital protuberance to a point approx 5 cm
superior to the external auditory meatus.
Essential image characteristics :
 The image should contain all cranial bones and the
first cervical vertebra.
 Should superimpose the floor of anterior cranial
fossa and posterior cranial fossa. The sella turcica
and clinoid processes should also be superimposed.

13. Fronto occipital view
Positioning :
 Patient lies supine on a bucky table. Head is adjusted to
bring the median sagittal plane at right angles to the
film.
 The external auditory meatuses are equidistance from
the cassette
 The orbito meatal baseline should be perpendicular to
the cassette

14. Central ray :
 Central ray is directed perpendicular to the cassette along
the medial sagittal plane and throw nasion.
 The field should be set to include the vertex of the skull
superiorly and base of the occipital bone inferiorly.

15. Towne’s view
fronto occipital 30 deg caudad
Positioning same as AP view
Certral ray :
 Its angled caudally so it makes 30 deg to the orbito
meatal plane
 Centre in the midline such that the beam passes
midway between external auditory meatuses. This is
a point approx 4 cm above the glabella

17. Essential image characteristics
 the sella turcica is projected with in the foramen
magnum.
 Include all the occipital bone and posterior parts of
parietal bone, and the lambdoidal suture should be
visualized clearly.

19. Occipito frontal view
Positioning of patient :
 Patient is seated facing the erect bucky, so that
the median sagittal plane is with the midline of the
bucky and perpendicular to it.
 Neck is flexed to bring orbito meatal line
perpendicular to the bucky, this can be achieved by
ensuring the nose and forehead are in contact with
the bucky.

21. Central ray :
 Ray is directed perpendicular to the bucky along the
median sagittal plane and at the level of nasion.
 Image should include the vertex superiorly and base
of occipital bone inferiorly

23. Caudal angulation :
 OF 0 deg : the petrous ridges completely
superimposed with orbit
 OF 10 deg : the petrous ridges appears in the middle
third of the orbit
 OF 20 deg : the petrous ridges appears just below
the inferior orbital margin.

24. Caldwell’s view
occipito frontal with 15 deg caudad
Positioning same as occipito frontal view
Central ray :
 Ray is directed perpendicular to the bucky alone
the median sagittal plane.
 The tube is rotated 15 deg caudal to the orbito
meatal baseline

27. Submento vertical view
Positioning of patient :
 Patient neck is hyperextended to bring the vertex
in contact with the cassette.
 The median sagittal plane should be right angle to
the cassette.
 The orbito meatal plane should be near as possible
and parallel to the cassette.

29. Central ray :
 Central ray is perpendicular to orbito meatal line.
 Center 1½ inch (4 cm) inferior to the mandibular
symphysis

30. Essential image characteratics :
 Should show the angles of mandible clear of the
petrous portion of temporal bone.
 The formina of the middle cranial fossa should be
seen symmetrically either side of the midline.

32. Occipito mental view
WATER’S VIEW
Positioning of patient :
 The patient is made to sit facing the cassette.
 Head is adjusted to bring orbito meatal line to 45 deg to the
cassette
 The patient’s nose and chin are placed in contact with the
midline of cassette.
 The patient should open the mouth as wide as possible before
exposure.

34. Central ray :
 The ray should is perpendicular to the median
sagittal plan.
 The ray should be centre to pass throw the base of
nose.

36. Thank
you!!!