I. Technique

  1. Use ellipse
  2. Transverse abdominal Triad
    1. Deep portion of Portal Vein (J Sign)
    2. Spine
    3. Stomach
  3. ObUltrasoundAbdominalCircumference.jpg
  4. ObUltrasoundAbdominalcircumference.gif

II. Equation

  1. Abdominal Circumference = (AP + Transverse) x 1.57

III. Accuracy

  1. Least accurate of measurements for estimating Gestational age (except 26-32 weeks)
  2. Most useful beyond 15 weeks for calculating fetal weight, serial growth and diagnosing IUGR
  3. References
    1. Benson (1991) AJR Am J Roentgenol 157(6):1275-7

IV. Resources

  1. AJR Online version of Benson and Doubilet article above
    1. http://www.ajronline.org/doi/pdf/10.2214/ajr.157.6.1950881

Images: Related links to external sites (from Google)