3. Abdomen Matrix

AP Supine: Patient and Part Position

• Supine with midsagittal plane centered to IR

• Arms laid to the side

• Legs bent with support under knees

AP Supine: CR, SID, and Respiration Instructions

• CR perpendicular IR at iliac crest

• SID: 40 Inches

• Expose on end of expiration

AP Supine: Structures Best Visualized

• Outline of liver, spleen, kidneys, psoas muscles, air-filled stomach/bowel segments, and arch of the symphysis pubis

AP Supine: Exposure Factors and Pathology

• kVp: 70-85

• Portrait

• Bowel obstruction, neoplasms, calcifications, ascites, and scout imaging for contrast studies

AP Erect: Patient and Part Position

• Upright, legs apart, back to IR

• Arms to the side

• Midsagittal plane of body centered to midline of table or erect bucky

AP Erect: CR, SID, and Respiration Instructions

• CR perpendicular to center of IR 2 inches above iliac crest

• SID: 40 Inches

• Expose at end of expiration

AP Erect: Structures Best Visualized

• Air-filled stomach/loops of bowel

• Air fluid levels where present

• Include bilateral diaphragms and as much of lower abdomen as possible

AP Erect: Exposure Factors and Pathology

• kVp: 70-85

• Portrait

• Abnormal masses, air-fluid levels, and accumilations of intraperitoneal air under the diaphragm

Decubitus: Patient and Part Position

• Lateral recumbent

• Arms up and near head

• IR firmly behind back and 2 inches above iliac crest

Decubitus: CR, SID, and Respiration Instructions

• CR horizontal to IR and 2 inches above iliac crest

• SID: 40 inches

• Expose on expiration

Decubitus: Structures Best Visualized

• Air-filled stomach and loops of bowel + air-fluid levels

Decubitus: Exposure Factors and Pathology

• kVp: 70-85

• Landscape

• Air-fluid levels, accumulation of intraperitoneal air, and abdominal masses