Gallbladder

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Gallbladder
The gallbladder sits beneath the liver
Details
PrecursorForegut
SystemDigestive system
ArteryCystic artery
VeinCystic vein
NerveCeliac ganglia, vagus nerve[1]
Identifiers
Latinvesica biliaris, vesica fellea
MeSHD005704
TA98A05.8.02.001
TA23081
FMA7202
Anatomical terminology

In

organ where bile is stored and concentrated before it is released into the small intestine. In humans, the pear-shaped gallbladder lies beneath the liver, although the structure and position of the gallbladder can vary significantly among animal species. It receives bile, produced by the liver, via the common hepatic duct, and stores it. The bile is then released via the common bile duct into the duodenum, where the bile helps in the digestion of fats
.

The gallbladder can be affected by gallstones, formed by material that cannot be dissolved – usually cholesterol or bilirubin, a product of hemoglobin breakdown. These may cause significant pain, particularly in the upper-right corner of the abdomen, and are often treated with removal of the gallbladder (called a cholecystectomy). Cholecystitis, inflammation of the gallbladder, has a wide range of causes, including result from the impaction of gallstones, infection, and autoimmune disease.

Structure

The gallbladder is a hollow grey-blue

organ that sits in a shallow depression below the right lobe of the liver.[2] In adults, the gallbladder measures approximately 7 to 10 centimetres (2.8 to 3.9 inches) in length and 4 centimetres (1.6 in) in diameter when fully distended.[3] The gallbladder has a capacity of about 50 millilitres (1.8 imperial fluid ounces).[2]

The gallbladder is shaped like a pear, with its tip opening into the

hepatic segments IVB and V.[5] The cystic duct unites with the common hepatic duct to become the common bile duct. At the junction of the neck of the gallbladder and the cystic duct, there is an out-pouching of the gallbladder wall forming a mucosal fold known as "Hartmann's pouch".[2]

Lymphatic drainage of the gallbladder follows the cystic node, which is located between the cystic duct and the common hepatic duct. Lymphatics from the lower part of the organ drain into lower hepatic lymph nodes. All the lymph finally drains into celiac lymph nodes.

Microanatomy

Micrograph of a normal gallbladder wall. H&E stain.

The gallbladder wall is composed of a number of layers. The innermost surface of the gallbladder wall is lined by a single layer of

serosa. Unlike elsewhere in the intestinal tract, the gallbladder does not have a muscularis mucosae, and the muscular fibres are not arranged in distinct layers.[6]

The

microvilli.[2] This sits on a thin layer of connective tissue, the lamina propria.[6] The mucosa is curved and collected into tiny outpouchings called rugae.[2]

A muscular layer sits beneath the mucosa. This is formed by smooth muscle, with fibres that lie in longitudinal, oblique and transverse directions, and are not arranged in separate layers. The muscle fibres here contract to expel bile from the gallbladder.[6] A distinctive feature of the gallbladder is the presence of Rokitansky–Aschoff sinuses, deep outpouchings of the mucosa that can extend through the muscular layer, and which indicate adenomyomatosis.[7] The muscular layer is surrounded by a layer of connective and fat tissue.[2]

The outer layer of the fundus of gallbladder, and the surfaces not in contact with the liver, are covered by a thick

serosa, which is exposed to the peritoneum.[2] The serosa contains blood vessels and lymphatics.[6] The surfaces in contact with the liver are covered in connective tissue.[2]

Variation

Abdominal ultrasonography showing gallbladder and common bile duct

The gallbladder varies in size, shape, and position among different people.[2] Rarely, two or even three gallbladders may coexist, either as separate bladders draining into the cystic duct, or sharing a common branch that drains into the cystic duct. Additionally, the gallbladder may fail to form at all. Gallbladders with two lobes separated by a septum may also exist. These abnormalities are not likely to affect function and are generally asymptomatic.[8]

The location of the gallbladder in relation to the liver may also vary, with documented variants including gallbladders found within,[9] above, on the left side of, behind, and detached or suspended from the liver. Such variants are very rare: from 1886 to 1998, only 110 cases of left-lying liver, or less than one per year, were reported in scientific literature.[10][11][2]

An anatomical variation can occur, known as a Phrygian cap, which is an innocuous fold in the fundus, named after its resemblance to the Phrygian cap.[12]

Development

The gallbladder develops from an

intestines.[13]

During the fourth week of embryological development, the stomach rotates. The stomach, originally lying in the midline of the embryo, rotates so that its body is on the left. This rotation also affects the part of the gastrointestinal tube immediately below the stomach, which will go on to become the

biliary tree. Just below this is a second outpouching, known as the cystic diverticulum, that will eventually develop into the gallbladder.[13]

Function

Accessory pancreatic duct, 17. Pancreatic duct.
18. Small intestine: 19. Duodenum, 20. Jejunum
21–22. Right and left kidneys.
The front border of the liver has been lifted up (brown arrow).[14]

The main functions of the gallbladder are to store and concentrate

biliary tree) into the gallbladder, where it is stored. At any one time, 30 to 60 millilitres (1.0 to 2.0 US fl oz) of bile is stored within the gallbladder.[15]

When food containing fat enters the

bile salts, and also acts as a means of eliminating bilirubin, a product of hemoglobin metabolism, from the body.[15]

The bile that is secreted by the liver and stored in the gallbladder is not the same as the bile that is secreted by the gallbladder. During gallbladder storage of bile, it is concentrated 3-10 fold[16] by removal of some water and electrolytes. This is through the active transport of sodium and chloride ions[17] across the epithelium of the gallbladder, which creates an osmotic pressure that also causes water and other electrolytes to be reabsorbed.[15]

A function of the gallbladder appears to be protection against carcinogenesis as indicated by observations that removal of the gallbladder (cholecystectomy) increases subsequent cancer risk. For instance, a systematic review and meta analysis of eighteen studies concluded that cholecystecomy has a harmful effect on the risk of right-sided colon cancer.[18] Another recent study reported a significantly increased total cancer risk, including increased risk of several different types of cancer, after cholecystectomy.[19]

Clinical significance

Main article: Gallbladder disease

Gallstones

Main article:
Gallstones
3D still showing gallstones

stone blocks the gallbladder, inflammation known as cholecystitis may result. If the stone lodges in the biliary system, jaundice may occur; if the stone blocks the pancreatic duct, pancreatitis may occur.[21] Gallstones are diagnosed using ultrasound.[20] When a symptomatic gallstone occurs, it is often managed by waiting for it to be passed naturally.[21] Given the likelihood of recurrent gallstones, surgery to remove the gallbladder is often considered.[21] Some medication, such as ursodeoxycholic acid, may be used; lithotripsy, a non-invasive mechanical procedure used to break down the stones, may also be used.[21]

Inflammation

Main article: Cholecystitis

Known as

cholelithiasis. Blocked bile accumulates, and pressure on the gallbladder wall may lead to the release of substances that cause inflammation, such as phospholipase. There is also the risk of bacterial infection. An inflamed gallbladder is likely to cause sharp and localised pain, fever, and tenderness in the upper, right corner of the abdomen, and may have a positive Murphy's sign. Cholecystitis is often managed with rest and antibiotics, particularly cephalosporins and, in severe cases, metronidazole. Additionally the gallbladder may need to be removed surgically if inflammation has progressed far enough.[21]

Gallbladder removal

Main article: Cholecystectomy

A

biliary tree. About 30 percent of patients may experience some degree of indigestion following the procedure, although severe complications are much rarer.[21] About 10 percent of surgeries lead to a chronic condition of postcholecystectomy syndrome.[23]

Complication

Main articles: Biliary injury and Biloma

Biliary injury (bile duct injury) is the traumatic damage of the

gall bladder, but can also be caused by other operations or by major trauma. The risk of biliary injury is more during laparoscopic cholecystectomy than during open cholecystectomy. Biliary injury may lead to several complications and may even cause death if not diagnosed in time and managed properly. Ideally biliary injury should be managed at a center with facilities and expertise in endoscopy, radiology and surgery.[24]

Biloma is collection of

laparoscopic cholecystectomy), with an incidence of 0.3–2%. Other causes are biliary surgery, liver biopsy, abdominal trauma, and, rarely, spontaneous perforation.[25]

Cancer

Main article:
Gallbladder carcinoma

Cancer of the gallbladder is uncommon and mostly occurs in later life. When cancer occurs, it is mostly of the glands lining the surface of the gallbladder (adenocarcinoma).[21] Gallstones are thought to be linked to the formation of cancer. Other risk factors include large (>1 cm) gallbladder polyps and having a highly calcified "porcelain" gallbladder.[21]

Cancer of the gallbladder can cause attacks of biliary pain, yellowing of the skin (

Liver function tests may be elevated, particularly involving GGT and ALP, with ultrasound and CT scans being considered medical imaging investigations of choice.[21] Cancer of the gallbladder is managed by removing the gallbladder, however, as of 2010, the prognosis remains poor.[21]

Cancer of the gallbladder may also be found incidentally after surgical removal of the gallbladder, with 1–3% of cancers identified in this way.

cholesterolosis ("strawberry gallbladder", a change in the gallbladder wall due to excess cholesterol[27]), often cause no symptoms and are thus often detected in this way.[21]

Tests

Abdominal ultrasonography showing biliary sludge and gallstones

Tests used to investigate for gallbladder disease include

CA 19-9 level may be taken to investigate for cholangiocarcinoma.[21]

An

nuclear imaging procedure used to assess the condition of the gallbladder.[28]

Other animals

Most

psittacine species), lampreys and all invertebrates do not have a gallbladder.[31][32]

The bile from several species of bears is used in

animal cruelty.[33][34]

History

Depictions of the gallbladder and biliary tree are found in Babylonian models found from 2000 BCE, and in ancient Etruscan model from 200 BCE, with models associated with divine worship.[35]

Diseases of the gallbladder are known to have existed in humans since antiquity, with gallstones found in the mummy of Princess Amenen of Thebes dating to 1500 BCE.[35][36] Some historians believe the death of Alexander the Great may have been associated with an acute episode of cholecystitis.[35] The existence of the gallbladder has been noted since the 5th century, but it is only relatively recently that the function and the diseases of the gallbladder has been documented,[36] particularly in the last two centuries.[35]

The first descriptions of gallstones appear to have been in the

eponymous Courvoisier's law, stated that in an enlarged, nontender gallbladder, the cause of jaundice is unlikely to be gallstones.[35]

The first surgical removal of a gallstone (cholecystolithotomy) was in 1676 by physician Joenisius, who removed the stones from a spontaneously occurring

Jean Louis Petit in the mid eighteenth century.[35] German surgeon Carl Langenbuch performed the first cholecystectomy in 1882 for a sufferer of cholelithiasis.[36] Before this, surgery had focused on creating a fistula for drainage of gallstones.[35] Langenbuch reasoned that given several other species of mammal have no gallbladder, humans could survive without one.[35]

The debate whether surgical removal of the gallbladder or simply gallstones was preferred was settled in the 1920s, with the consensus that removal of the gallbladder was preferred.

contrast medium and CT scans were used to view the gallbladder.[35] The first laparoscopic cholecystectomy performed by Erich Mühe of Germany in 1985, although French surgeons Phillipe Mouret and Francois Dubois are often credited for their operations in 1987 and 1988 respectively.[38]

Society and culture

To have "gall" is associated with bold, belligerent behaviour, whereas to have "bile" is associated with sourness.[39]

In the Chinese medicine, the gallbladder (膽) is associated with the Wuxing element of wood, in excess its emotion is belligerence and in deficiency cowardice and judgement, in the Chinese language it is related to a myriad of idioms, including using terms such as "a body completely [of] gall" (渾身是膽) to describe a forward person, and "single, alone gallbladder hero" (孤膽英雄) to describe a lone hero, or "they have a lot of gall to talk like that".[40]

In the

Chinese medicine it is an extraordinary Fu or yang organ, as it holds bile. The gallbladder not only has a digestive role, but is seen as the seat of decision-making and judgement.[40]

See also

References

  1. ^ Ginsburg, Ph.D., J.N. (August 22, 2005). "Control of Gastrointestinal Function". In Thomas M. Nosek, Ph.D. (ed.). Gastrointestinal Physiology. Essentials of Human Physiology. Augusta, Georgia, United States: Medical College of Georgia. pp. p. 30. Archived from the original on April 1, 2008. Retrieved June 29, 2007.
  2. ^ a b c d e f g h i j k l Gray's Anatomy 2008, p. 1187-81.
  3. ISBN 978-0-8493-4788-7
    .
  4. PMID 21206646
    .
  5. ^ Shakelford's Surgery of Alimentary Tract, ed.7. 2013
  6. ^
    ISBN 978-0-443-06850-8
    .
  7. ISBN 978-0-7817-7200-6
    .
  8. S2CID 2581053
    .
  9. PMID 25659400. Archived from the original
    on March 4, 2016.
  10. PMID 18333151
    .
  11. S2CID 30176379
    .
  12. PMID 1950867
    .
  13. ^
    ISBN 978-0-443-06811-9
    .
  14. ISBN 978-0-8089-2371-8
    .
  15. ^
    ISBN 978-0-7216-0240-0.{{cite book}}: CS1 maint: multiple names: authors list (link
    )
  16. S2CID 27488720
    .
  17. PMID 16089346
    .
  18. ^ Mu L, Li W, Ren W, Hu D, Song Y. The association between cholecystectomy and the risk of colorectal cancer: an updated systematic review and meta-analysis of cohort studies. Transl Cancer Res. 2023 Jun 30;12(6):1452-1465. doi: 10.21037/tcr-22-2049. Epub 2023 May 22. PMID: 37434692; PMCID: PMC10331452
  19. ^ Choi YJ, Jin EH, Lim JH, Shin CM, Kim N, Han K, Lee DH. Increased Risk of Cancer after Cholecystectomy: A Nationwide Cohort Study in Korea including 123,295 Patients. Gut Liver. 2022 May 15;16(3):465-473. doi: 10.5009/gnl210009. PMID: 35502586; PMCID: PMC9099388
  20. ^ a b c "Cholelithiasis - Hepatic and Biliary Disorders - MSD Manual Professional Edition". MSD Manual Professional Edition. Retrieved October 18, 2017.
  21. ^
    ISBN 978-0-7020-3085-7
    .
  22. PMID 17761085
    .
  23. ^ nhs.uk, Complications of a gallbladder removal
  24. PMID 17909716
  25. ^ Norton J. Greenberger; et al. (2009), "Endoscopic Management of Acute Biliary & Pancreatic Conditions", Gastroenterology, Hepatology, and Endoscopy, Current Medical Diagnosis and Treatment, pp. 355–356
  26. ^ "Gallbladder Polyps". MayoClinic. Retrieved March 19, 2015.
  27. ^ Strawberry gallbladder – cancerweb.ncl.ac.uk.
  28. ^ "HIDA scan - Overview". Mayo Clinic. Retrieved October 18, 2017.
  29. ^ C. Michael Hogan. 2008. Guanaco: Lama guanicoe, GlobalTwitcher.com, ed. N. Strömberg Archived March 4, 2011, at the Wayback Machine
  30. PMID 26559382
    .
  31. ISBN 978-0-03-910284-5
    .
  32. PMID 21113274
    .
  33. ^ Actman, Jani (May 5, 2016). "Inside the Disturbing World of Bear-Bile Farming". National Geographic. Archived from the original on May 5, 2016. Retrieved October 23, 2017.
  34. ^ Hance, Jeremy (April 9, 2015). "Is the end of 'house of horror' bear bile factories in sight?". The Guardian. Retrieved October 23, 2017.
  35. ^
    ISBN 9783319148243
    .
  36. ^
    ISBN 978-1455746064
    .
  37. ^
    ISBN 9789400941731
    .
  38. PMID 11304004
    .
  39. ISBN 9781787752764
    .
  40. ^
    S2CID 143595915
    .
Books

External links

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