Abdomen AP Upright

Abdomen positioning

Abdomen AP Upright is a radiography positioning projection of the Abdomen. Erect against vertical Bucky, back straight, arms at sides. SID 40". The centering point is located 2 inches above iliac crest at midline.. The central ray is perpendicular to ir at 2 inches above iliac crest at midline.. Image-quality criteria include diaphragm visible above ribs at top of image., pubic symphysis or ischial tuberosities visible at bottom.. Standard exposure ranges from 70 to 80 kVp, 30 to 60 mAs, at an SID of 40 inches (102 cm).

Anatomy demonstrated

  • Diaphragm and lower lung lobes.
  • Liver and spleen outlines.
  • Stomach bubble.
  • Small bowel loops.
  • Colon.
  • Peritoneal fat stripe.

Patient preparation

  • Verify patient identity using two identifiers.
  • Ask patient to remove all radiopaque objects from waist up.
  • Position patient standing upright against vertical Bucky.
  • Instruct patient to stand straight, arms at sides.
  • Have patient breathe normally; suspend respiration at full inspiration.

Position & centering point

2 inches above iliac crest at midline.

Central ray

Perpendicular to IR at 2 inches above iliac crest at midline.

Exposure / technique

kVp
70–80
mAs
30–60
SID
40" (102 cm)
Notes
Grid required. Longer exposure time for erect posture to show air-fluid levels.

Image-quality criteria

  • Diaphragm visible above ribs at top of image.
  • Pubic symphysis or ischial tuberosities visible at bottom.
  • Entire abdomen shown between diaphragm and pubis.
  • Air-fluid levels clearly demonstrated.
  • Free gas visible if present (pneumoperitoneum).
  • No motion blur; structures sharp throughout.

Common errors / ARRT traps

  1. 1 Patient slouching shortens abdomen and distorts anatomy.
  2. 2 Arms hanging down or crossed overlay abdomen.
  3. 3 CR too low excludes diaphragm and upper abdomen.
  4. 4 Patient motion during longer exposure blurs anatomy.

Clinical indications

  • Acute abdominal pain evaluation (obstruction, perforation, free air).
  • Bowel obstruction assessment.
  • Pneumoperitoneum detection.
  • Urinary calculus search.

Aligned to the 2025 ARRT Content Specifications.

Practice this projection live.

The interactive positioning viewer in the app lets you rotate the patient, see the centering point in 3D, and study the central ray angle. Start free.

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