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Radiographic Technique 2

RAD 1204

A . Tahani Ahmed AL-Hozeam

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TECHNICAL ASPECTSTECHNICAL 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) spineAP thoracic (dorsal) spine BB

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

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Lateral thoracic (dorsal) spineLateral thoracic (dorsal) spine BB

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 Anterior OR Posterior Obliques thoracic spine BB

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 )

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AP lumbar spineAP lumbar spine BB

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 SpineLateral Lumbar Spine BB

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)AP axial lumbosacral joint (L5-S1) SS

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)Lateral lumbosacral spine (L5 – S1) BB

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 spinePO or AO lumbar spine BB

For zygoapophyseal joints.

Patient semi-supine (for RPO and LPO) or semi-prone (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 sacrumAP axial sacrum BB

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.

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AP axial coccyxAP axial coccyx BB

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 coccyxLateral sacrum and coccyx BB

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)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)TABLE 4 (Exposure Factors)

PROJECTION kVp mAs AP Axial Sacrum 80 15

AP Axial Coccyx 80 15

Lateral Sacrum and Coccyx 90 55