Lobes of liver

The liver is grossly divided into two portions – a right and a left lobe, as viewed from the front (diaphragmatic) surface; but the underside (the visceral surface) shows it to be divided into four lobes and includes the caudate and quadrate lobes.[1]

Lobes of liver
The liver is divided into four lobes. This image shows the large right lobe and a smaller left lobe separated by the falciform ligament.
Details
Identifiers
Latinlobus hepatis
Anatomical terminology

The falciform ligament, visible on the front of the liver, divides the liver into a left and a much larger right lobe. From the underside, the two additional lobes are located between the right and left lobes. A line can be imagined running from the left of the vena cava and all the way forward to divide the liver and gallbladder into two halves.[2] This line is called "Cantlie's line".[3]

Other anatomical landmarks exist, such as the ligamentum venosum and the round ligament of the liver (ligamentum teres), which further divide the left side of the liver in two sections. An important anatomical landmark, the porta hepatis, also known as the transverse fissure of the liver, divides this left portion into four segments, which can be numbered starting at the caudate lobe as I in an anticlockwise manner. From this parietal view, seven segments can be seen, because the eighth segment is only visible in the visceral view.[4]

Labeled human liver

Structure

Left lobe

The left lobe is smaller and more flattened than the right. It is situated in the epigastric and left hypochondriac regions. Its upper surface is slightly convex and is moulded on to the diaphragm; its under surface presents the gastric impression and omental tuberosity.

Right lobe

The right lobe is much larger than the left; the proportion between them being as six to one.

It occupies the right hypochondrium; on its posterior surface by the ligamentum venosum for the cranial (upper) half, and by the ligamentum teres hepatis (Round ligament of liver) for the caudal (under) half. The ligamentum teres hepatis turns around the inferior marging of the liver to come out ventral in the falciform ligament.

The right lobe is functionally separated from the left lobe by the middle hepatic vein. A common misconception is that the falciform ligament separates the two lobes. However, from a functional perspective (one that takes the arterial, portal venous, and systemic venous anatomy into account) the falciform ligament separates the medial and lateral segments of the left hepatic lobe.[5]

The right lobe is of a somewhat quadrilateral form. Its under and posterior surfaces being marked by three fossæ: the fossa for the portal vein, the fossa for the gall-bladder and the fossae for the inferior vena cava. These separate the right lobe in two smaller lobes on its left posterior part: the quadrate lobe and the caudate lobe.

Quadrate lobe

The quadrate lobe is an area of the liver situated on the under surface of the medial segment left lobe (Couinaud segment IVb), bounded in front by the anterior margin of the liver; behind by the porta hepatis; on the right, by the fossa for the gall-bladder; and on the left, by the fossa for the umbilical vein.

It is oblong in shape, its antero-posterior diameter being greater than its transverse.

Caudate lobe

The caudate lobe (posterior hepatic segment I, Spigelian lobe) is situated upon the postero-superior surface of the liver on the right lobe of the liver, opposite the tenth and eleventh thoracic vertebrae.

The caudate lobe of the liver is bounded below, by the porta hepatis; on the right, by the fossa for the inferior vena cava; and, on the left, by the fossa for the ductus venosus and the physiological division of the liver called the ligamentum venosum. It looks backward, being nearly vertical in position; it is longer from above downward than from side to side, and is somewhat concave in the transverse direction. It is situated behind the porta, and separates the fossa for the gall-bladder from the commencement of the fossa for the inferior vena cava.

Budd–Chiari syndrome, caused by occlusion of hepatic venous outflow, can lead to hypertrophy of the caudate lobe due to its own caval anastomosis that allows for continued function of this lobe of the liver.

The caudate lobe is named after the tail-shaped hepatic tissue (cauda; Latin, "tail") papillary process of the liver, which arise from its left side. It also has a caudate process (that is not tail-like shaped) arising from its right side which provides surface continuity between the caudate lobe and the visceral surface of the anatomical right lobe of the liver.[6] The caudate process is a small elevation of the hepatic substance extending obliquely and laterally, from the lower extremity of the caudate lobe to the under surface of the right lobe.

References

This article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)

  1. "Anatomy of the Liver". Liver.co.uk. Retrieved 2015-06-26.
  2. Renz, John F.; Kinkhabwala, Milan (2014). "Surgical Anatomy of the Liver". In Busuttil, Ronald W.; Klintmalm, Göran B. (eds.). Transplantation of the Liver. Elsevier. pp. 23–39. ISBN 978-1-4557-5383-3.
  3. "Cantlie's line | Radiology Reference Article". Radiopaedia.org. Retrieved 2015-06-26.
  4. Kuntz, Erwin; Kuntz, Hans-Dieter (2009). "Liver resection". Hepatology: Textbook and Atlas (3rd ed.). Springer. pp. 900–3. ISBN 978-3-540-76839-5.
  5. Abdel-Misih, Sherif R. Z.; Bloomston, Mark (August 2010). "Liver Anatomy". Surg Clin North Am. Elsevier. 90 (4): 643–53. doi:10.1016/j.suc.2010.04.017. PMC 4038911. PMID 20637938.
  6. Moore. Clinically Oriented Anatomy - 8th edition. Wolters Kluwer.
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