LATERAL PROJECTION - RAO OR LAO: SCAPULA

Sunday, May 20, 2012

Pathology Demonstrated:

  • Horizontal fractures of the scapula are demonstrated. Arm placement should be determined be scapular area of interest.


Technical Factors:

  • IR size - 24 x 30 cm (10 x 12 inches), lengthwise
  • Moving or stationary grid
  • Manual exposure factors (AEC is not recommended)
  • Digital IR - requires very close collimation
  • 75 +- 5 kV range


Shielding:

  • Secure gonadal shield around waist.


Patient Position:

  • Perform radiograph with the patient in an erect or recumbent position. (The erect position id preferred if patient's condition allows.) Face patient toward IR in an anterior oblique position.


Part Position (Erect):

Lateral scapula, RAO body position
  • Have patient reach across front of chest and gasp opposite shoulder. This best demonstrate body of scapula or
  • Have patient drop affected arm, flex elbow, and place arm behind lower back with arm partially abducted, or just let arm hang down at patient's side. This best demonstrated acromion and coracoid processes.
  • Palpate borders of scapula and rotate patient until the scapula is in a true lateral position. The average patient will be rotated 30 to 40 degrees from the lateral position, which results in a 45 to 60 degrees anterior oblique position. The position of humerus (down at side or up across anterior chest) has an effect on the amount of body rotation required. Less rotation is required with arm up across anterior chest. (The flat posterior surface of body of scapula should be perpendicular to the IR.)
  • Align patient to center midvertebral border to CR and to IR.


Central Ray:

  • CR to mid-vertebral border of scapula
  • Minimum 40 inches (100 cm) SID


Collimation:

  • Collimate to area of scapula.


Respiration:

  • Suspend respiration during exposure.


Radiographic Criteria:

Structure Shown and Position:

Lateral scapula with arm on posterior chest.
  • Entire scapula should be visualized in a lateral position, as evidenced by direct superimposition of vertebral and lateral borders.
  • True lateral is shown by direct superimposition of vertebral and lateral borders.
  • Body of scapula should be in profile, free of superimposition be ribs.
  • As much as possible, the humerus should not superimpose area of interest of the scapula.


Collimation and CR:

  • Collimation should be visualized on four sides to area of scapula.
  • CR and center of collimation field to, lateral border of midscapula.


Exposure Criteria:

  • Optimal exposure with no motion will demonstrate sharp bony borders and trabecular markings without excessive density in area of inferior angle.
  • Bony borders of both the acromion and coracoid processes should be seen through the head of the humerus.

Subscribe your email address now to get the latest articles from us

 
Copyright © 2015. RadTechOnDuty.
Design by Herdiansyah Hamzah. Published by Themes Paper. Powered by Blogger.
Creative Commons License