Hepatic veins ultrasound anatomy

Hepatic Veins Ultrasound Anatomy

---

The hepatic veins are an essential structure in ultrasound anatomy as they provide critical information about the liver's venous drainage and can help diagnose various pathologies, such as cirrhosis, portal hypertension, and hepatic venous obstruction.
Below is an explanation of the ultrasound anatomy of the hepatic veins, including their role, locations, and characteristics during ultrasound imaging:

---

The hepatic veins originate from the periphery of the liver, converging into the inferior vena cava (IVC). LHV, left hepatic vein; MHV, middle hepatic vein; RHV, right hepatic vein.
1. Location and Anatomy
The hepatic veins are responsible for draining deoxygenated blood from the liver into the inferior vena cava (IVC). There are typically three main hepatic veins:

• Right Hepatic Vein (RHV)
• Middle Hepatic Vein (MHV)
• Left Hepatic Vein (LHV)

These veins are positioned to drain the liver’s segments as follows:

• Right Hepatic Vein: Drains the right lobe of the liver.
• Middle Hepatic Vein: Drains the central part of the liver, typically between the right and left lobes.
• Left Hepatic Vein: Drains the left lobe of the liver.

---

2. Ultrasound Visualization
The hepatic veins are best visualized using transabdominal ultrasound.

• The liver’s inferior surface (especially the right lobe) is where the hepatic veins can be seen entering the inferior vena cava (IVC).
• The hepatic veins typically show a pulsatile flow pattern with bidirectional flow on Doppler ultrasound.

---

3. Normal Ultrasound Appearance
Gray-Scale Imaging:

• The hepatic veins appear as anechoic (black) structures on gray-scale imaging.
• They are seen as parallel lines within the liver, usually running perpendicular to the portal vein.

Doppler Imaging:

• Doppler ultrasound provides detailed information about blood flow through the hepatic veins.
• The flow in hepatic veins is typically pulsatile and bidirectional (with systolic and diastolic flow patterns).

Hepatic Vein Diameter by Age (Ultrasound)

---

Age Group	Normal Hepatic Vein Diameter
Neonates (0–1 month)	1.5 – 3.5 mm
Infants (1–12 months)	2.0 – 4.5 mm
Children (1–10 years)	3.0 – 6.0 mm
Adolescents (11–18 years)	4.0 – 7.0 mm
Adults (18+ years)	Up to ~8 mm (normal upper limit)

Hepatic Vein Doppler Normal Ranges

Hepatic Vein Doppler Normal Ranges

Parameter	Normal Range	Notes
Hepatic Vein Diameter	≤ 8 mm	May increase in hepatic congestion or disease
Hepatic Vein Velocity (PSV)	15 – 30 cm/s	Monophasic hepatopetal flow
Hepatic Vein Flow Direction	Hepatopetal	Should always flow toward the liver
Hepatic Vein Pulsatility Index (PI)	0.5 – 1.0	Higher values may indicate liver congestion or right heart dysfunction

---

Parameter Descriptions

PSV (Peak Systolic Velocity): Highest flow speed during systole.

PI (Pulsatility Index): Measure of the variation in velocity during the cardiac cycle.

Hepatopetal = toward liver; Hepatofugal = away from liver.

---

Notes:

Measurements are typically taken at the level of the hepatic hilum and perpendicular to the vessel.

In conditions like portal hypertension or right heart failure, you may see altered Doppler waveforms such as reversed flow or blunted waveforms.

Hepatic veins can show dampened or monophasic flow in hepatic congestion, especially in cirrhosis or Budd-Chiari syndrome.

---

Common Hepatic Vein Variations

1. Hepatic Vein Trifurcation: A variation where the main hepatic vein divides into three branches instead of two.

2. Early Branching of Right Hepatic Vein: In some cases, the right hepatic vein branches early before entering the liver.

3. Hepatic Vein Congenital Absence: Rare condition where a hepatic vein may be congenitally absent or malformed.

---

Clinical Relevance

Portal Hypertension: Elevated pressure in the portal system can lead to dilated hepatic veins and abnormal Doppler patterns.

Hepatic Vein Thrombosis: Obstruction of the hepatic veins can lead to hepatomegaly, ascites, and hepatocellular damage.

Budd-Chiari Syndrome: Hepatic vein thrombosis can cause liver congestion, leading to severe symptoms.

TIPS Procedure: Transjugular Intrahepatic Portosystemic Shunt (TIPS) is a treatment for portal hypertension that connects the portal vein to the hepatic vein.

---

4. Hepatic Veins and Blood Flow
Normal Flow: Hepatic veins carry blood from the liver toward the inferior vena cava. On Doppler, you should see a pulsatile waveform because the venous return is influenced by the cardiac cycle.

• Systolic flow (toward the heart)
• Diastolic flow (away from the heart), especially during ventricular relaxation.

Normal Waveform Characteristics:

• Hepatic veins typically show a regular triphasic waveform, with both systolic and diastolic flow.
• The normal velocity of blood in the hepatic veins is typically between 10 and 30 cm/s.

---

5. Pathological Findings in Hepatic Veins
When assessing the hepatic veins in ultrasound, certain pathological conditions can alter the normal appearance of the veins. a) Cirrhosis:

• Cirrhosis can cause liver fibrosis, leading to increased resistance in the hepatic venous outflow.
• This can result in abnormal Doppler flow patterns, such as reversed flow or reduced pulsatility.

b) Portal Hypertension:

• Portal hypertension leads to increased pressure in the portal venous system and can cause hepatic vein dilation and abnormal flow.
• Reversed or dampened flow in the hepatic veins on Doppler may be observed due to the high pressure in the portal circulation.

c) Hepatic Vein Obstruction (Budd-Chiari Syndrome):

• In hepatic vein thrombosis or Budd-Chiari syndrome, there may be complete or partial obstruction of the hepatic veins, leading to reversed blood flow and distended hepatic veins.
• This condition is characterized by the absence of the typical pulsatile flow and can cause hepatomegaly, ascites, and liver congestion.

d) Hepatic Vein Thrombosis:

• Hepatic vein thrombosis results in a loss of the normal pulsatile pattern in the Doppler waveform.
• This can be seen with liver congestion and ascites.

---

6. How to Visualize Hepatic Veins on Ultrasound
To visualize the hepatic veins properly:

• Patient Position: The patient should be in a supine position with the right arm extended to allow better access to the liver.
• Probe Selection: Use a curved array probe for optimal imaging, typically 2-5 MHz in frequency.
• Scan Plane: Start with the longitudinal view of the liver and then rotate to a transverse view to visualize the hepatic veins draining into the IVC.
• Doppler Settings: Apply Doppler on the hepatic veins, focusing on the flow pattern in both systole and diastole. You should see a pulsatile wave that is normal in healthy patients.

---

7. Hepatic Veins Doppler Imaging in Normal vs. Abnormal Conditions
Normal:

• Clear, pulsatile flow pattern.
• Triphasic waveform.

Abnormal (in pathologies like cirrhosis, portal hypertension, or Budd-Chiari Syndrome):

• Monophasic waveform.
• Absence of diastolic flow.
• Dampened or reversed flow.
• Reduced pulsatility or loss of triphasic waveforms.

Related MCQ

---

Hepatic Veins Ultrasound – MCQ Quiz

Note: If you select English, answer all questions in English.
यदि आप हिंदी चुनते हैं, तो सभी प्रश्न हिंदी में हल करें।

1. Which hepatic vein drains the right lobe of the liver? 1. कौन सी हेपेटिक वेन यकृत के दाएं लव को ड्रेन करती है?
A. Right Hepatic Vein / दाएं हेपेटिक वेन
B. Left Hepatic Vein / बाएं हेपेटिक वेन
C. Middle Hepatic Vein / मध्य हेपेटिक वेन
D. Inferior Vena Cava / इन्फीरियर वेना कावा

2. What type of flow is typically seen in the hepatic veins on Doppler ultrasound? 2. डोप्लर अल्ट्रासाउंड पर सामान्य रूप से हेपेटिक वेन में किस प्रकार का प्रवाह देखा जाता है?
A. Monophasic / मोनोफेजिक
B. Biphasic / बाइफेजिक
C. Triphasic / त्रैतीयक
D. Continuous / निरंतर

3. Which of the following is the primary function of the hepatic veins? 3. निम्नलिखित में से कौन सा हेपेटिक वेन्स का प्राथमिक कार्य है?
A. Draining deoxygenated blood from the liver / यकृत से ऑक्सीजन रहित रक्त को बाहर निकालना
B. Transporting oxygenated blood to the liver / यकृत में ऑक्सीजन युक्त रक्त का परिवहन करना
C. Transporting bile to the gallbladder / पित्त को पित्ताशय में परिवहन करना
D. Supplying nutrients to the liver / यकृत को पोषक तत्वों की आपूर्ति करना

4. What pathology might be suggested by a monophasic waveform in the hepatic veins? 4. हेपेटिक वेन्स में मोनोफेजिक वेवफॉर्म से कौन सी पैथोलॉजी का सुझाव मिल सकता है?
A. Hepatic vein thrombosis / हेपेटिक वेन थ्रोम्बोसिस
B. Cirrhosis / सिरोसिस
C. Portal hypertension / पोर्टल उच्च रक्तचाप
D. All of the above / उपरोक्त सभी

5. The hepatic veins are best visualized in which part of the liver? 5. हेपेटिक वेन्स को यकृत के किस हिस्से में सबसे अच्छा देखा जा सकता है?
A. Right lobe / दायां लव
B. Left lobe / बायां लव
C. Caudate lobe / कौडेट लव
D. All of the above / उपरोक्त सभी

6. Which condition is associated with hepatic vein obstruction? 6. कौन सा स्थिति हेपेटिक वेन अवरोध से जुड़ी है?
A. Hepatic vein thrombosis / हेपेटिक वेन थ्रोम्बोसिस
B. Budd-Chiari syndrome / बुद्ध-चियारी सिंड्रोम
C. Cirrhosis / सिरोसिस
D. All of the above / उपरोक्त सभी

7. What is the typical velocity range in hepatic veins on Doppler ultrasound? 7. डोप्लर अल्ट्रासाउंड पर हेपेटिक वेन्स में सामान्य वेग सीमा क्या है?
A. 10 – 30 cm/s / 10 – 30 सेमी/सेकंड
B. 30 – 50 cm/s / 30 – 50 सेमी/सेकंड
C. 50 – 70 cm/s / 50 – 70 सेमी/सेकंड
D. 70 – 90 cm/s / 70 – 90 सेमी/सेकंड

8. Which of the following is an abnormal finding in hepatic veins on ultrasound? 8. अल्ट्रासाउंड पर हेपेटिक वेन्स में निम्नलिखित में से कौन सा असामान्य पाया जाता है?
A. Reversed flow / उल्टा प्रवाह
B. Hepatopetal flow / हेपटोपेटल प्रवाह
C. Triphasic waveform / त्रैतीयक वेवफॉर्म
D. Continuous flow / निरंतर प्रवाह

9. Hepatic vein pulsatility index (PI) values greater than 1 may indicate which condition? 9. हेपेटिक वेन पल्सटिलिटी इंडेक्स (PI) मान 1 से अधिक होने पर किस स्थिति का संकेत हो सकता है?
A. Right heart dysfunction / दायें हृदय का कार्य
B. Hepatic vein thrombosis / हेपेटिक वेन थ्रोम्बोसिस
C. Portal hypertension / पोर्टल उच्च रक्तचाप
D. All of the above / उपरोक्त सभी

10. What is the primary role of the hepatic veins in the body? 10. शरीर में हेपेटिक वेन्स की मुख्य भूमिका क्या है?
A. Draining oxygenated blood from the liver / यकृत से ऑक्सीजनयुक्त रक्त को बाहर निकालना
B. Draining deoxygenated blood from the liver / यकृत से ऑक्सीजन रहित रक्त को बाहर निकालना
C. Transporting bile from liver to gallbladder / यकृत से पित्ताशय तक पित्त का परिवहन करना
D. Supplying nutrients to the liver / यकृत को पोषक तत्वों की आपूर्ति करना