Longitudinal Scanning of the Liver Through the Abdominal Aorta

Longitudinal liver section • Abdominal aorta • Subxiphoid approach

Scanning Method

The patient should be fasted for 8–12 hours and examined in the supine position. Place the ultrasound probe vertically in the midline at the subxiphoid region. Adjust the probe to obtain the longitudinal section of the left hepatic lobe together with the abdominal aorta and the relevant adjacent structures.

Key scanning point: Start from the subxiphoid midline with the probe vertically oriented. The abdominal aorta is used as an important anatomical landmark for establishing the longitudinal plane.

Ultrasound Image

Figure 1. Longitudinal section of the liver and abdominal aorta. Insert the corresponding ultrasound image in the space above.

Anatomical / Scanning Diagram

Figure 8.2: Diagram space for the probe orientation, scanning plane, liver, abdominal aorta, and labeled anatomical landmarks.

1.1.2 Section Structure

The principal structures demonstrated in this plane are the longitudinal section of the left hepatic lobe and the abdominal aorta, with an oblique section of the esophagus. The adjacent vascular structures help confirm the correct anatomical orientation.

Structures to identify

• Left hepatic lobe
• Abdominal aorta
• Esophagus (oblique section)
• Celiac artery
• Splenic artery
• Splenic vein
• Superior mesenteric artery
• Pancreatic body
• Left atrium

Abbreviations Used in the Figure

Abbreviation	Full form	Role / identification
LL	Left lobe	Longitudinally visualized left hepatic lobe.
CA	Celiac artery	Arterial branch arising from the abdominal aorta.
LA	Left atrium	Cardiac structure included as an adjacent landmark in the depicted plane.
PB	Pancreatic body	Part of the pancreas seen adjacent to the vascular structures.
SpV	Splenic vein	Venous structure coursing toward the portal venous system.
SpA	Splenic artery	Arterial branch related to the celiac trunk.
SMA	Superior mesenteric artery	Arterial branch arising inferior to the celiac artery.
Ao	Aorta / abdominal aorta	Major arterial landmark used to establish the scanning plane.
E	Esophagus	Obliquely visualized esophageal section.

1.1.3 Measuring Method and Normal

Measure the anteroposterior (AP) diameter of the left hepatic lobe from the top of the anterior hepatic capsule to the posterior capsule in the appropriate longitudinal section.

Measurement	Caliper method	Reference value from the supplied source
Left hepatic lobe AP diameter	Measure from the top of the anterior capsule to the posterior capsule.	< 7 cm in the normal liver.

Measurement note: Keep the measurement in the standardized longitudinal plane and document the plane and measurement direction with the value.

1.1.4 The Clinical Application Value

This plane is described as a standard section for measuring the anteroposterior diameter of the left liver lobe. It also permits assessment of the liver's size, shape, and parenchymal echogenicity.

• Standard plane for left hepatic lobe AP measurement.
• Assessment of left-lobe size.
• Assessment of hepatic shape and contour in the demonstrated plane.
• Assessment of hepatic parenchymal echogenicity.
• Recognition of the abdominal aorta as a major orientation landmark.
• Recognition of the adjacent celiac, splenic and superior mesenteric vessels.

Quick Scanning Checklist

1	Fast the patient for 8–12 hours.
2	Position the patient supine.
3	Place the probe vertically at the midline of the subxiphoid region.
4	Obtain the longitudinal left-lobe view with the abdominal aorta.
5	Identify the labeled vascular and adjacent structures.
6	Measure the AP diameter of the left hepatic lobe from anterior to posterior capsule.
7	Compare the measurement with the supplied reference of <7 cm.
8	Assess liver size, shape and parenchymal echogenicity.