Sunday, November 9, 2008

How to do apical view?

The apical view is done to assess the apical region. In the apex, super-imposition of the first and 2nd ribs and the clavicle may obscure or mimic pathology.

How do we position the patient?
There are 2 principal versions of the projection. However all the general principal is to "stretch out" the lung apices and avoid superimposition of the clavicles over the apices. The differences between the projections are,

a) Horizontal central ray with patient's coronal plane angled i.e lordotic
b) Angled central ray with patient erect

If you need to show fluid level in a cystic structure, the first position is better.
However, the second position is more comfortable and safer for the patient.

Position 1: Horizontal central ray -patient's coronal plane angled (lordotic)
The patient stands AP erect approximately 30 cm from the cassette then leans back so the coronal plane is 30 degrees parallel to the cassette, the head and dorsal skin surface in contact with the cassette, the backs of the hands are placed on the lateral aspects of the waist and the shoulders rolled forward. Exposure is made on suspended inspiration. FFD is 100cm.

Position 2: Angled central ray with patient erect
The patient stands AP erect with the back parallel to the cassette. The tube is angled 30 degrees cephalad. FFD is 100cm.

Radiation protection: Always ask the patient to wear lead apron.
Central Ray: The horizontal central ray is centered in the midline midway between the sternal notch and the xiphisternum, the top of the cassette needs to be approximately 10 cm above the apical skin surface.

Evaluation of the Image:

  • ID and markers must be present and correct in the appropriate area of the film.
  • Limits of anatomy, superiorly the skin margins of the apices, inferiorly the T4, laterally the ribcage.
  • No rotation, The apices should be symmetrical about the midline.
  • Centering at T6The medial ends of the clavicles should be projected above the lung apices.
  • The scapulae should be clear of the lungfields.
  • Penetration: the vertebral outlines should be visible.
  • Density: the average density of the lung field should be approximately 1.

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