Oblique Scanning of the Liver Through the Hepatic Veins and the Second Porta Hepatis on Subxiphoid

Oblique liver section • Hepatic Veins • Second Porta Hepatis on Subxiphoid approach

Scanning Method

The patient should be fasted for 8–12 hours and examined in the supine position. Place the ultrasound probe obliquely in the subxiphoid region and angle it toward the left upper abdomen. Adjust the probe orientation, angulation, depth, and pressure to obtain a clear oblique section through the hepatic veins and the second porta hepatis. The scan should demonstrate the left hepatic lobe (LL), right hepatic lobe (RL), middle hepatic vein (MHV), right hepatic vein (RHV), left hepatic vein (LHV), inferior vena cava (IVC), and diaphragm (Dia) as appropriate. Optimize the imaging parameters to clearly demonstrate the hepatic veins as they converge toward the IVC and their relationship to the surrounding hepatic parenchyma.

Key scanning point: Begin from the subxiphoid region with the probe oriented obliquely toward the left upper abdomen. Use gentle probe angulation and pressure to obtain an appropriate view of the hepatic veins and second porta hepatis. Identify the MHV, RHV, and LHV as they course through the hepatic parenchyma toward the IVC. The right and left hepatic lobes and the diaphragm provide additional anatomical reference points. Optimize depth, gain, and focal position to maintain a well-defined hepatic parenchymal image and clearly demonstrate the hepatic veins in relation to the IVC and adjacent hepatic structures.

Ultrasound Image

Figure 1.1 Oblique sonographic section of the liver obtained through the subxiphoid approach, demonstrating the middle hepatic vein (MHV), right hepatic vein (RHV), left hepatic vein (LHV), inferior vena cava (IVC), right hepatic lobe (RL), left hepatic lobe (LL), and diaphragm (Dia), illustrating the hepatic veins and their relationship to the IVC and adjacent hepatic parenchyma.

Anatomical / Scanning Diagram

Figure 1.2: Diagram showing the subxiphoid probe orientation and oblique scanning plane through the liver, demonstrating the left hepatic lobe (LL), right hepatic lobe (RL), middle hepatic vein (MHV), right hepatic vein (RHV), left hepatic vein (LHV), inferior vena cava (IVC), and diaphragm (Dia), illustrating the anatomical relationship of the hepatic veins to the IVC.

Section Structure

The principal structures demonstrated in this oblique subxiphoid plane include the left hepatic lobe (LL), middle hepatic vein (MHV), left hepatic vein (LHV), right hepatic vein (RHV), right hepatic lobe (RL), inferior vena cava (IVC), and diaphragm (Dia). These structures provide important anatomical landmarks for assessment of the hepatic veins and their convergence at the second porta hepatis.

Structures to identify

• Left hepatic lobe (LL)
• Middle hepatic vein (MHV)
• Left hepatic vein (LHV)
• Right hepatic vein (RHV)
• Right hepatic lobe (RL)
• Inferior vena cava (IVC)
• Diaphragm (Dia)
• Hepatic parenchyma

Abbreviations Used in the Figure

Short form	Full form	Identification
LL	Left hepatic lobe	Hepatic parenchyma of the left hepatic lobe demonstrated in the upper portion of the scanning field.
MHV	Middle hepatic vein	Major hepatic vein coursing between the functional right and left hepatic lobes and draining toward the IVC.
LHV	Left hepatic vein	Hepatic vein draining the left hepatic lobe and converging toward the IVC.
RHV	Right hepatic vein	Hepatic vein coursing through the right hepatic lobe and draining toward the IVC.
RL	Right hepatic lobe	Hepatic parenchyma of the right hepatic lobe surrounding the hepatic venous structures.
IVC	Inferior vena cava	Major retrohepatic venous structure receiving the hepatic veins.
Dia	Diaphragm	Echogenic diaphragmatic interface forming the superior boundary adjacent to the hepatic dome.

Measuring Method and Normal

In this oblique subxiphoid plane, measurements may be obtained when clinically indicated. The IVC and selected hepatic venous structures should be assessed only when they are clearly visualized and the imaging plane is appropriate. Calipers should be positioned perpendicular to the structure being measured and measurements should be interpreted according to the imaging plane, respiratory phase, and clinical context.

Measurement	Caliper method	Reference / interpretation
IVC	Measure the internal diameter perpendicular to the long axis of the IVC when an appropriate standardized view is obtained.	Interpret according to respiratory phase, measurement level, patient position, and clinical context.
Hepatic veins	Assess the caliber and course of the MHV, LHV, and RHV when clearly visualized.	Interpret the appearance together with Doppler flow characteristics and the clinical context.

Measurement note: Obtain measurements only when the target structure is clearly defined. Avoid oblique measurements and inclusion of adjacent hepatic parenchyma or vascular structures.

The Clinical Application Value

This oblique subxiphoid plane provides an important anatomical overview of the hepatic veins and their relationship to the IVC. It demonstrates the MHV, LHV, RHV, LL, RL, and Dia and is useful for anatomical orientation at the second porta hepatis.

• Demonstration of the left hepatic lobe (LL).
• Identification of the middle hepatic vein (MHV).
• Identification of the left hepatic vein (LHV).
• Identification of the right hepatic vein (RHV).
• Demonstration of the right hepatic lobe (RL).
• Recognition of the IVC as the major venous drainage landmark for the hepatic veins.
• Recognition of the diaphragm (Dia) as an important superior anatomical landmark.
• Assessment of the relationship of the hepatic veins to the second porta hepatis.
• Assessment of the surrounding hepatic parenchyma.

Quick Scanning Checklist

1	Fast the patient for 8–12 hours when appropriate.
2	Position the patient in the supine position.
3	Place the probe obliquely in the subxiphoid region.
4	Angle the probe toward the left upper abdomen.
5	Obtain a clear oblique hepatic section.
6	Identify the LL and RL.
7	Identify the MHV, LHV, and RHV.
8	Identify the IVC and demonstrate the convergence of the hepatic veins toward it.
9	Identify the Dia as the superior diaphragmatic landmark.
10	Optimize depth, gain, focus, and probe pressure for clear visualization.

Diagnostic Pathology

This oblique subxiphoid view can assist in the assessment of hepatic venous and hepatic parenchymal abnormalities. The MHV, LHV, RHV, IVC, LL, RL, and Dia should be evaluated together with the complete abdominal sonographic examination and Doppler assessment when indicated.

Key Sonographic Findings

• Hepatic venous abnormality: Altered caliber, contour, course, or Doppler flow involving the MHV, LHV, or RHV.
• Hepatic venous obstruction: Abnormal narrowing, non-visualization, or altered flow involving one or more hepatic veins.
• Hepatic venous thrombosis: Intraluminal echogenic material or abnormal/absent Doppler flow within a hepatic vein when identified.
• IVC abnormality: Altered caliber, narrowing, compression, thrombus, or other intraluminal abnormality involving the IVC.
• Hepatic congestion: Abnormal hepatic venous Doppler pattern or associated hepatic parenchymal changes in the appropriate clinical setting.
• Hepatic steatosis: Increased hepatic echogenicity with variable posterior attenuation and reduced visualization of deeper structures.
• Hepatomegaly: Increased hepatic size with alteration of normal hepatic contour or morphology.
• Cirrhotic change: Coarse hepatic echotexture, irregular contour, and altered hepatic architecture.
• Focal hepatic lesion: Focal abnormality differing in echogenicity or architecture from the surrounding hepatic parenchyma.
• Diaphragmatic abnormality: Altered appearance or disruption of the normally visualized diaphragmatic interface when identified.
• Second porta hepatis abnormality: Abnormal relationship, distortion, or adjacent mass effect involving the hepatic veins and IVC should be documented when present.

Diagnostic note: Sonographic findings should be interpreted together with the complete abdominal ultrasound examination, Doppler assessment, clinical history, and relevant laboratory findings. A single sonographic finding should not be used in isolation to establish a diagnosis.