Figure 3-43. A left posterior oblique (LPO) or left anteroposterior (AP) oblique
projection or right anterior projection.
Figure 3-44. Right posterior oblique (RPO) or right anteroposterior oblique.
d. Decubitus Projections. To obtain a decubitus projection, the portent must
be in a decubitus (lying down) position. In addition, the central ray (CR) must be
parallel to the horizon (horizontal). For most dacubitus protections the patient assumes
a lateral decubitus position, that is, lying on either side. Like the lateral and oblique
positions, decubitus positions are named according to the body surface on which the
patient is lying.
(1) Left lateral decubitus position. When the patient assumes the left lateral
decubrtus position (figure 3-45), an AP radiographic projection is produced. Such a
projection is particularly useful in diagnosing abdomen and chest air-fluid levels.
Figure 3-45. A left lateral decubitus position yields an AP projection.
MD0961
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