Transcript LUM-DORS

Radiographic Technique 2
RAD 1204
A . Tahani Ahmed AL-Hozeam
1
TECHNICAL ASPECTS
A moving or a stationary grid must be used.
Relatively high kV is used, range is (80 - 95) KVp,
(95 -100) kVp for lateral L/S) to increase exposure latitude and reduces patient’s dose.
All part supports and pads mentioned are radiolucent.
The anode heel-effect must be observed, with anode at the head side (a wedge-filter
or graduated screens can be used instead) to produce overall uniform spine density.
Radiosensitive areas must be well covered by shields.
Collimation must be strictly applied in all projections to improve image contrast and
reduce patient’s dose and amount of scatter.
Optimal density and contrast are necessary for an optimal image quality.
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AP thoracic (dorsal) spine
B
AP thoracic (dorsal spine): For #s and pathology
(compression, kyphosis, and subluxation).
Patient supine with head under anode side to observe
the heel-effect, both knees and hips flexed to reduce
thoracic curvature and arms stretched by the side.
Exposure at end of arrested expiration to reduce volume
of air in thorax for more uniform density of whole dorsal
vertebrae ,MSP: 90 to the film. FFD=100cm
Film: HD 35x43 cm, lengthwise.
CP: T7 ( 3 – 5 cm below the sternal angle, or 8 – 10 cm
below jugular notch) as for the PA chest.
CR: 90 Vertically to the thoracic spine
3
Lateral thoracic (dorsal) spine
B
Lateral thoracic spine: For #s and pathology
(compression, kyphosis, or suluxation).
Patient in a lateral recumbent, with head on pillow and
both knees flexed and arms stretched at right angles,
waist supported, anode heel-effect should be well
observed. Exposure at end of arrested expiration, or
during quiet breathing using low mA and long exposure
time (3 - 4 s) to diffuse the lung and ribs shadows. A lead
blocker sheet near patient’s back helps stop scatter rays .
MSP: parallel. FFD=100cm.
Film: HD 35x43 cm lengthwise.
CP: T7 ( 3 - 5 cm below the sternal angle, or 8 – 10 cm
below jugular notch).
CR: 90 Vertically to the thoracic spine
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Anterior OR Posterior Obliques thoracic spine
B
Zygapophyseal joints of the thoracic spine. Both right and left
obliques are taken for comparison.
Patient in a lateral recumbent or in lateral erect, body rotated
20 from true lateral, flex elbow and arm nearest couch must be
down , opposite arm must be rise. Exposure at end of
suspended full expiration. FFD=100cm.
Film: HD 35x43 cm lengthwise.
CP: T7 ( 5 cm below the sternal angle, 8 – 10 cm below
jugular notch).
CR: 90 V/H to film center.( vertically in table , horizentally in
backy )
5
AP lumbar spine
B
AP five lumbar vertebral bodies and intervertebral
spaces, spinous and transverse processes, S.I. joints
and sacrum. For #s, pathology (scoliosis and
neoplastic processes of the lumbar spine).
Patient supine , head on pillow and knees flexed with
feet on the couch top, arms at the sides or on the
chest, exposure must be during a quiet breathing at
low mA and long exposure time to diffuse colonic gas
shadows. Exposure at end of full expiration. Female
ovarian shielding obscures portions of sacrum and
coccyx. FFD=100cm.
Film: HD 35x43 cm lengthwise.
CP: Large film (35x43) cm: L4 – L5 (level of iliac
crest).
Small film (30x24) cm: L3 (level of lower costal margins).
CR: 90 Vertically to film center.
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Lateral Lumbar Spine
B
Lateral lumbar vertebral bodies, spinous processes, L5 – S1
junction, and sacrum. Rules-out compression, neoplastic
processes, #s of lumbar spine.
Patient in a lateral recumbent, knees flexed, support between
knees and ankles, pad under the waist, a piece of lead rubber
behind the lumbar region on couch top to improve contrast
(by absorbing scatter). Exposure at end of arrested
expiration. FFD=100cm.
Film: HD 35x43 cm lengthwise .
CP: Large film: L4 – L5 (level of iliac crest).
Small film: L3 (level f lower costal margins).
CR: 90 Vertically to center of film
NB/ Lateral for trauma can be done with patient in (supine
decubitus), with same CP and horizontal beam.
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AP axial lumbosacral joint (L5-S1)
S
For pathology of AP (L5 – S1) articulation and AP
sacro - iliac joints.
Patient supine with pillow for head, legs extended,
both knees flexed slightly over support, arms at
sides or on the chest, shield gonads without
obscuring area of interest, Female ovarian
shielding obscures portion of sacroiliac joints.
Film: HD 18x24 cm crosswise.
CP:
Level of ASIS (anterior superior iliac supine).
CR:
30 cephalic (males), 35 cephalic (females).
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Lateral lumbosacral spine (L5 – S1)
B
For lat L5 – S1 joint space, and for spondylolisthesis or
other pathologies of L4 to L5, or L5 to S1
Patient in a lateral recumbent, the knees flexed, support
between knees and the ankles, pad under the waist, rubber
sheet behind the lumbar region.
Film: HD 18x24 cm lengthwise. FFD= 100cm.
CP: 4 cm inferior to iliac crest.
CR: 90 Vertically to film center (with sufficient waist
support), angle 5 ْ to 10 caudal for waist (with no
support).
NB/ Close collimation is necessary because of the high amount of
secondary radiation produced in this view.
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PO or AO lumbar spine
B
For zygoapophyseal joints.
Patient semi-supine (for RPO and LPO) or semiprone (for RAO and LAO), body then rotated 45,
knee flexed, lower back supported with pads.
Film: HD 30x35 cm lengthwise.
CP: 4 cm above of iliac crest.
CR: 90 vertical to film center
NB/ Semi-supine: 45 RPO (for R downside zygo.
joints).
Semi-prone : 45 LAO (for L downside zygo.
joints).
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AP axial sacrum
B
Pathology of sacrum , S.I. joints, and L5 – S1
junction.
NB/ Urinary bladder should be emptied before this
examination .
Cleansing enema must
also be done to clean the colon of fecal material.
Patient supine with pillow under head, legs
extended, support under the knees. Exposure
during arrested expiration. shield gonads for
male, ovarian shielding on female is not
possible without obscuring area of interest.
Film: HD 24x30 cm lengthwise. FFD=100cm.
CP: Mid sagittal plane midway between level of
the symphysis pubis and ASIS.
CR: 15 cephalad.
11
AP axial coccyx
B
For pathology of the coccyx.
NB/ Urinary bladder should be emptied before this
examination .
Cleansing enema must also be done to clean the colon of
fecal material.
Patient supine with pillow under head, legs extended,
support under the knees. Exposure during arrested
expiration. shield gonads for male, ovarian shielding on
female is not possible without obscuring area of
interest.
Film: HD 24x30 cm lengthwise.
CP: 5 cm superior to the symphysis pubis.
CR: 10 caudad.
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Lateral sacrum and coccyx
B
For pathology of the sacrum and coccyx.
(urinary bladder and the colon should be
emptied before examination from their
contents. Cleansing enema is used for the
colon.
Patient in a lateral recumbent, knees
flexed, support under the waist and
between knee and ankles.
Film: HD 18x24 cm lengthwise.
FFD=100cm.
CP: 8-10 cm posterior to ASIS.
CR: 90 V to film center.
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TABLE 4 (Exposure Factors)
PROJECTION
kVp
mAs
AP Thoracic Spine
90
7
Lateral Thoracic Spine
80
50
AO Thoracic Spine
80
26
AP Lumbar Spine
80
15
AP Axial Lumbosacral Spine Joint (L5 – S1)
80
20
Lateral Lumbosacral Spine Joint (L5 – S1)
100
50
Lateral Lumbar Spine
90
65
AO Lumbar Spine
85
15
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TABLE 4 (Exposure Factors)
PROJECTION
kVp
mAs
AP Axial Sacrum
80
15
AP Axial Coccyx
80
15
Lateral Sacrum and Coccyx
90
55
15