10  Abdomen Scan

10.1 Overview

10.1.1 Terminology

  • U/S Whole Abdomen = All abdominal organs
  • U/S Upper Abdomen = All abdominal organs - (Bladder & Reproductive orgs)
  • U/S KUB = Kidneys + Bladder + Reproductive orgs

10.1.2 Echogenicity

Relative echogenicity on ultrasound (high to low):

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(Ref: radiopedia)

10.2 Liver

10.2.1 Overview

  • Subcostal: Transverse & longitudinal view of RL & LL (LL must includes caudate lobe)

  • Intercostal: RL

Beware

Blind spot of liver at “superior portion of Rt lobe”

Figure 10.1: Liver scan plane [1]

10.2.2 Measure

  • Normal liver span: 15 - 17 cm (sagital, at MCL)

  • Enlarge: > 15.5 cm

  • Hepatomegaly: confident if liver extend to caudal of Rt kidney

(Ref from [2])

10.2.3 View: Longitudinal

Figure 10.2: Superior border: longitudinal view [1]

Figure 10.3: Inferior border: longitudinal view [1]

Figure 10.4: Superior border: drawing [1]

Figure 10.5: Inferior border: drawing [1]

10.2.4 View: Transverse

Figure 10.6: Left lobe: transverse view [1]

Figure 10.7: Right lobe: transverse view [1]

Figure 10.8: Transverse view drawing [1]

10.3 Gallbladder

  • View: transverse & longitudinal

  • Measure:

    • Diameter: long (9 - 11 cm), TV (< 4 cm)
    • Wall thickness at anterior wall in TV section (< 3 mm)

Figure 10.9: Gallbladder: a shot to take [1]

10.4 Porta Hepatis

10.4.1 Measure: CBD & PV

CBD

  • Measure: internal diameter
    • < 0.6 cm (< 0.9 for post-cholecystectomy)
    • Age > 60 yrs can dilate 0.1 cm / 10 yrs

PV

  • Measure: internal diameter < 13 mm
  • Flow direction: hepatopetal ? (toward liver) or hepatofugal ? (away from liver)

10.4.2 View: CBD & PV

View: longitudinal scan (with lt lateral decubitus) to see porta hepatis Figure 10.10

Figure 10.10: Porta hepatis: CBD and PV [1]

Tips: identifying CBD

  • CBD will appear anterior and parellel to PV and IVC.
  • Color doppler will show no flow at CBD.

10.5 Pancreas

10.5.1 View

View: transverse view, angle the probe slightly upward to the liver.

  • use splenic vein as a land mark

  • The money shot of the pancrease is shown in Figure 10.11.

Figure 10.11: Pancrease: transverse view [3]

Figure 10.12: Pancrease: drawing in transverse view [3]

10.5.2 Finding pancreas

Figure 10.13: Pancrease: landmark vessels [1]

Figure 10.14: Pancrease: scanning from rostal to caudal [1]

10.5.3 Tips

Pancrease is best examined in fasted patient.

If bowel gas obstruct the view, try:

  • Examine after the patient change position:

    • From lateral decubitus to supine, or
    • From supine to upright (sit).
  • Use acoustic windows:

    • Let the patient drink some water to fill in the stomach.

    • View through the liver.