Longitudinal Scanning of the Left Hepatic LobeThrough the Caudate Lobe and Medial Lobe
Scanning Method
The patient should be fasted for 8–12 hours and examined in the supine position. Place the ultrasound probe longitudinally in the midline at the subxiphoid region. Direct the probe to obtain a longitudinal section of the left hepatic lobe through the caudate lobe and medial lobe. Adjust the probe angle, depth, and position to clearly demonstrate the hepatic parenchyma, caudate lobe, medial (quadrate) lobe, and relevant adjacent vascular structures.
Ultrasound Image
Figure 1.1 Longitudinal section of the left hepatic lobe through the caudate lobe and medial lobe on subxiphoid scanning. Insert the corresponding ultrasound image in the space above.
Anatomical / Scanning Diagram
Figure 1.2: Diagram space showing the probe orientation, longitudinal scanning plane, left hepatic lobe, caudate lobe, medial lobe, and labeled anatomical landmarks.
Section Structure
The principal structures demonstrated in this plane are the left hepatic lobe, caudate lobe, and medial lobe, with the portal vein, common bile duct, and inferior vena cava providing important anatomical landmarks.
Structures to identify
- Left hepatic lobe (LL)
- Caudate lobe (CL)
- Medial / quadrate lobe
- Venous ligament (VL)
- Common bile duct (CBD)
- Portal vein (PV)
- Inferior vena cava (IVC)
- Hepatic parenchyma
- Adjacent vascular structures
Abbreviations Used in the Figure
| Short form | Full form | Identification |
|---|---|---|
| LL | Left lobe | Left hepatic lobe. |
| CL | Caudate lobe | Caudate lobe adjacent to the IVC. |
| VL | Venous ligament | Ligamentum venosum between the left lobe and caudate lobe. |
| CBD | Common bile duct | Main extrahepatic biliary duct. |
| PV | Portal vein | Portal venous structure at the hepatic hilum. |
| IVC | Inferior vena cava | Major venous landmark posterior to the liver. |
| 1 | Numbered structure | Reference point indicated in the diagram. |
Measuring Method and Normal
In this longitudinal subxiphoid plane, measurements may be obtained when clinically indicated. The portal vein and common bile duct should be measured only when clearly visualized and using a standardized caliper technique.
| Measurement | Caliper method | Reference / interpretation |
|---|---|---|
| Portal vein (PV) | Measure the internal diameter with the calipers positioned appropriately across the vessel lumen. | Interpret with Doppler findings and the clinical context. |
| Common bile duct (CBD) | Measure the duct from inner wall to inner wall at an appropriate visualized segment. | Interpret according to age, clinical setting, and biliary anatomy. |
Measurement note: Keep the measured structure clearly visualized and place the calipers perpendicular to its long axis where appropriate. Document the measurement site and technique.
The Clinical Application Value
This plane provides a useful longitudinal view of the left hepatic lobe through the caudate and medial lobes. It allows assessment of the hepatic parenchyma, caudate lobe, venous ligament, portal vein, common bile duct, and IVC.
- Demonstration of the left hepatic lobe in longitudinal section.
- Identification of the caudate lobe.
- Recognition of the medial / quadrate lobe.
- Identification of the venous ligament.
- Visualization of the portal vein and common bile duct.
- Recognition of the IVC as a posterior vascular landmark.
- Assessment of hepatic parenchymal echogenicity and contour.
Quick Scanning Checklist
| 1 | Fast the patient for 8–12 hours when appropriate. |
| 2 | Position the patient supine. |
| 3 | Place the probe longitudinally at the subxiphoid midline. |
| 4 | Obtain the longitudinal view of the left hepatic lobe. |
| 5 | Identify the caudate lobe and medial lobe. |
| 6 | Identify the VL, CBD, PV, and IVC. |
| 7 | Assess hepatic contour and parenchymal echogenicity. |
| 8 | Obtain vascular or biliary measurements when clinically indicated. |
Diagnostic Pathology
This longitudinal subxiphoid view can assist in identifying hepatic, portal venous, biliary, and IVC abnormalities. Evaluate the left hepatic lobe, caudate lobe, medial lobe, portal vein, common bile duct, and IVC.
Key Sonographic Findings
- Hepatomegaly: Increased hepatic size with altered contour or morphology.
- Hepatic steatosis: Increased hepatic echogenicity with reduced visualization of deeper structures.
- Cirrhotic change: Coarse echotexture, irregular contour, and altered hepatic architecture.
- Caudate lobe enlargement: Enlargement of the caudate lobe, particularly in the setting of chronic liver disease.
- Focal liver lesion: Focal abnormality differing from the surrounding hepatic parenchyma.
- Portal vein abnormality: Altered caliber, course, continuity, or Doppler flow of the PV.
- Portal vein thrombosis: Intraluminal material with partial or complete obstruction of portal venous flow.
- Biliary dilatation: Enlargement of the CBD or intrahepatic bile ducts.
- Choledocholithiasis: Echogenic intraductal focus, often with posterior acoustic shadowing, when a ductal stone is visualized.
- Hilar abnormality: Abnormal tissue or structural distortion involving the portal region.
- IVC abnormality: Altered caliber, focal narrowing, intraluminal material, or compression.
- Venous ligament abnormality: Altered appearance or surrounding structural distortion of the VL.
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