Critique of the Cervical & Thoracic Vertebrae

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Critique of the Cervical &
Thoracic Vertebrae
Chapter 7
Cervical Vertebrae (AP)
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Contrast & density: demonstrate soft tissue,
air filled trachea, & bony structures
Good penetration: shows T & C of vertebral
bodies, uncinate processes, spinous
processes, and anterior tubercles
75 to 80 kVp with grid
Control patient motion, stop breathing, &
short OID
Cervical Vertebrae (AP)
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? True AP
?spinous processes aligned with midline of
cervical bodies, mandibular angles, and
mastoid tips are equal distances from c-spine
?articular pillars and pedicles symmetric and
seen lateral to c-bodies
?distances from vertebral column to medial
(sternal) ends of clavicles equal
Cervical Vertebrae (AP)
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Rotation is present if:
1) mandibular angles and mastoid tips are not seen
at equal distances from the C-vertebrae
2) spinous processes are not seen in midline of Cbodies
3)pedicles & articular pillars are not symmetrically
seen lateral to vertebral bodies
4) medial ends of clavicles are not seen at equal
distances from vertebral column
** For trauma, remember what to do!
Cervical Vertebrae (AP)
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?intervertebral disk spaces open
?vertebral bodies seen without distortion
?each vertebral spinous process is seen at the level
of it inferior intervertebral disk space
?lordotic curvature
? Central ray angled to open disk spaces and
undistorted vertebral bodies
AP erect- 20 degree cephalad
AP supine- 15 degree cephalad ( due to lordotic
curvature is straightened when supine)
Cervical Vertebrae ( AP)
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? All of 3rd cervical vertebrae seen, and posterior
occiput & mandibular mentum superimposed
?long axis of cervical column aligned
?5th cervical vertebra in center of field, showing 3rd –
7th c-vertebrae with 1st thoracic vertebra on film
?acanthiomeatal line (imaginary line from upper lip,
and below nose to external ear opening)
perpendicular to tabletop or upright grid
Cervical Vertebrae (AP- Atlas & Axis)
Open Mouth Position
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No preventable artifacts (dentures, hairpins)
Good penetration – see atlas’s lateral
masses & transverse processes & the axis’s
dens spinous process & body (70 to 80 kVp)
?true AP – atlas is symmetrically seated on
axis with atlas’ lateral masses at equal
distances from dens. Spinous process of axis
aligned with midline of axis’s body,
mandibular rami seen at equal distances from
lateral masses
Cervical Vertebrae –(AP Atlas & Axis)
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Determine rotation by judging the distance
between the mandibular rami and the lateral
masses. Side showing greater distance is
side the face is rotated toward
?upper incisors & posterior occiput’s inferior
edge seen superior to the dens & atlantoaxial
joint
?atlantoaxial joint open & axis’s spinous
process seen in midline and inferior to dens
?dens centered in field
Cervical Vertebrae (lateral)
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75 to 80 kVp- see air filled trachea,
prevertebral fat stripe (in front of anterior
surfaces of vertebrae) abnormal widening of
the space between these two detects
?fractures, masses, and inflammation
Grid is optional due to long OID (air gap
technique) 72 inch SID to reduce
magnification
Cervical Vertebrae (lateral)
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? True lateral: rt & lt sides of each cervical
vertebrae are superimposed, showing the spinous
processes and vertebral bodies in profile.
To prevent rotation superipose the patient’s
shoulders, mastoid tips, & mandibular rami.
3 goals: alignment of the cervical vertebral column
parallel with film, demonstration of C1 and C2
without occiput or mandibular superimposition, and
superimposition of the anterior, posterior,superior,
and inferior aspects of the cranial and mandibular
cortices
Cervical Vertebrae (lateral)
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?long axis of cervical vertebral column
aligned with long axis
Extension & flexion films are for
anteroposterior vertebral mobility
?C-4 in center of field
Use weights, pull down on recumbent
patients or do swimmer’s view
Cervical Vertebrae ( Anterior & posterior
obliques)
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Anterior oblique places the intervertebral
foramina of interest closer to the film
Posterior oblique places the intervertebral
foramina of interest farther from the film.
? Cervical vertebrae rotated 45 degrees
?not rotated enough: intervertebral foramina
are narrowed or obscured, pedicles are
foreshortened & vertebral column are
superimposed
Cervical Vertebrae (Anterior & posterior
obliques)
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? Rotated too much: one side of pedicles
partially foreshortened, but other side is
aligned with midline of vertebral bodies &
zygapophyseal joints shown without vertebral
body superimposition are open
?cranium in lateral position
? Long axis of cervical vertebral column
aligned
?C5 in center of field
CervicoThoracic vertebrae (Swimmer’s
lateral position)
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80 to 90 kVp
?cervicothoracic vertebrae in a true lateral position
?intervertebral disk spaces open & vertebral bodies
shown without distortion
?long axis of cervicothoracic column aligned with
long axis of film
?T 1 in center of field (C5-C7 with T 1,2, &3
?if needed a 5 degree caudal central ray angle can
be used.
Thoracic Vertebrae ( AP)
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75 to 85 kVp
?use wedge or anode heel effect
Expiration exposure decreases the thoracic cavity’s
radiographic density by reducing the air volume and
compressing the tissue in this area. This allows us
to see posterior ribs and mediastinum region better
?true lateral thoracic vertebral
?intervertebral disk spaces open & vertebral bodies
seen without distortion
For kyphotic patients do erect
?long axis of thoracic aligned with T7 in center of
field
Thoracic Vertebrae (lateral)
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80 to 90 kVp
Due to lungs & axillary ribs, use breathing technique: long
exposure time(3 to 4 seconds) and ask patient to breathe
shallowly and steady, upward and outward movement of ribs and
lungs. This causes blurring of ribs and lung markings resulting in
greater thoracic vertebral visualization
?true lateral thoracic vertebrae
?intervertebral disk spaces open and vertebral bodies shown
without distortion
?long axis aligned
?T7 in center of field
?T 12 on film, follow last rib
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