Editing Gallbladder

{{short description|Organ in humans and other vertebrates}}
{{good article}}
{{pp-pc}}
{{Use mdy dates|date=May 2016}}
{{Use American English|date=May 2016}}
{{Infobox anatomy
| Name        = Gallbladder
| Latin       = vesica biliaris, vesica fellea
| Image       = Gallbladder (organ).png
| Caption     = Diagram of human gallbladder
| Width       =
| Image2      = 2425 Gallbladder.jpg
| Caption2    = The gallbladder sits beneath the liver
| Precursor   = [[Foregut]]
| System      = [[Digestion|Digestive system]]
| Artery      = [[Cystic artery]]
| Vein        = [[Cystic vein]]
| Nerve       = [[Celiac ganglia]], [[vagus nerve]]<ref>{{cite book | last = Ginsburg, Ph.D. | first = J.N. | editor = Thomas M. Nosek, Ph.D. | title = Gastrointestinal Physiology | series = Essentials of Human Physiology | url = http://www.lib.mcg.edu/edu/eshuphysio/program/section6/6ch2/s6ch2_30.htm | access-date = June 29, 2007 | date = August 22, 2005 | publisher = [[Medical College of Georgia]] | location = Augusta, Georgia, United States | pages = [http://www.lib.mcg.edu/edu/eshuphysio/program/section6/6ch2/s6ch2_30.htm p. 30] | chapter = Control of Gastrointestinal Function | chapter-url = http://www.lib.mcg.edu/edu/eshuphysio/program/section6/6ch2/6ch2line.htm | url-status = dead | archive-url = https://web.archive.org/web/20080401093403/http://www.lib.mcg.edu/edu/eshuphysio/program/section6/6ch2/s6ch2_30.htm | archive-date = April 1, 2008 | df = mdy-all }}</ref>
| Lymph       =
}}

In [[vertebrate]]s, the '''gallbladder''', also known as the '''cholecyst''', is a small hollow [[Organ (anatomy)|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 [[fat]]s.

The gallbladder can be affected by [[gallstone]]s, 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 human gallbladder is a hollow grey-blue [[Organ (anatomy)|organ]] that sits in a shallow depression below the right lobe of the [[liver]].{{sfn|Gray's Anatomy|2008|p=1187-81}} In adults, the gallbladder measures approximately {{convert|7|to|10|cm|abbr=off}} in length and {{convert|4|cm|in}} in diameter when fully distended.<ref name="meilstrup">{{cite book |author=Jon W. Meilstrup |title=Imaging Atlas of the Normal Gallbladder and Its Variants |publisher=CRC Press |location=Boca Raton |year=1994 |page=4 |isbn=978-0-8493-4788-7 }}</ref> The gallbladder has a capacity of about {{convert|50|ml|impoz|abbr=off}}.{{sfn|Gray's Anatomy|2008|p=1187-81}}

The gallbladder is shaped like a pear, with its tip opening into the [[cystic duct]].<ref name="Nagral2005">{{cite journal|last1=Nagral|first1=Sanjay|title=Anatomy relevant to cholecystectomy|journal=Journal of Minimal Access Surgery|date=2005|volume=1|issue=2|pages=53–8|doi=10.4103/0972-9941.16527|pmid=21206646|pmc=3004105 |doi-access=free }}</ref> The gallbladder is divided into three sections: the ''fundus'', ''body'', and ''neck''. The ''fundus'' is the rounded base, angled so that it faces the [[abdominal wall]]. The ''body'' lies in a depression in the surface of the lower liver. The ''neck'' tapers and is continuous with the [[cystic duct]], part of the [[biliary tree]].{{sfn|Gray's Anatomy|2008|p=1187-81}} The gallbladder fossa, against which the fundus and body of the gallbladder lie, is found beneath the junction of [[hepatic segments]] IVB and V.<ref>Shakelford's Surgery of Alimentary Tract, ed.7. 2013</ref> 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 "[[Henri Albert Hartmann|Hartmann]]'s pouch".{{sfn|Gray's Anatomy|2008|p=1187-81}}

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===
[[File:Gallbladder - intermed mag.jpg|thumb|[[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 [[columnar epithelia|columnar cells]] with a [[brush border]] of [[microvilli]], very similar to intestinal absorptive cells.{{sfn|Gray's Anatomy|2008|p=1187-81}} Underneath the epithelium is an underlying [[lamina propria]], a [[muscular layer]], an outer perimuscular layer and [[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.<ref name=WHEATERS>{{cite book| first2=Philip J. | last2=Deakin (drawings) | first1=Barbara | last1=Young | title=Wheater's functional histology: a text and colour atlas | url=https://archive.org/details/wheatersfunction00youn | url-access=limited | year=2006 | publisher=Churchill Livingstone/Elsevier | location=[Edinburgh?] | isbn=978-0-443-06850-8 | edition=5th | page=[https://archive.org/details/wheatersfunction00youn/page/n671 298] | display-authors=1}}</ref>

The [[mucous membrane|mucosa]], the inner portion of the gallbladder wall, consists of a [[epithelium|lining]] of a [[Simple columnar epithelium|single layer of columnar]] cells, with cells possessing small hair-like attachments called [[microvilli]].{{sfn|Gray's Anatomy|2008|p=1187-81}} This sits on a thin layer of connective tissue, the [[lamina propria]].<ref name=WHEATERS /> The mucosa is curved and collected into tiny outpouchings called ''rugae''.{{sfn|Gray's Anatomy|2008|p=1187-81}}

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.<ref name=WHEATERS /> 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]].<ref name="ross">{{cite book|title=Histology: A Text and Atlas|url=https://archive.org/details/histologytextatl00ross_530|url-access=limited|publisher=Lippincott Williams & Wilkins|last1=Ross|first1=M.|last2=Pawlina|first2=W.|year=2011|isbn=978-0-7817-7200-6|page=[https://archive.org/details/histologytextatl00ross_530/page/n665 646]|edition=6th}}</ref> The muscular layer is surrounded by a layer of connective and [[adipose tissue|fat]] tissue.{{sfn|Gray's Anatomy|2008|p=1187-81}}

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]].{{sfn|Gray's Anatomy|2008|p=1187-81}} The serosa contains blood vessels and lymphatics.<ref name=WHEATERS /> The surfaces in contact with the liver are covered in [[connective tissue]].{{sfn|Gray's Anatomy|2008|p=1187-81}}

===Variation===
[[File:Gallbladder and common bile duct ultrasound.jpg|thumb|left|[[Abdominal ultrasonography]] showing gallbladder and common bile duct]]
The gallbladder varies in size, shape, and position among different people.{{sfn|Gray's Anatomy|2008|p=1187-81}} 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.<ref>{{cite journal|last=Leeuw|first=Th.G.|author2=Verbeek, P.C.M. |author3=Rauws, E.A.J. |author4= Gouma, D.J. |title=A double or bilobar gallbladder as a cause of severe complications after (laparoscopic) cholecystectomy|journal=Surgical Endoscopy|date=September 1995|volume=9|issue=9|doi=10.1007/BF00188459 |pmid=7482221|pages=998–1000|s2cid=2581053}}</ref>

The location of the gallbladder in relation to the liver may also vary, with documented variants including gallbladders found within,<ref>{{cite journal|last1=Segura-Sampedro |first1=JJ |last2=Navarro-Sánchez |first2=A |last3=Ashrafian |first3=H |last4=Martínez-Isla |first4=A |title=Laparoscopic approach to the intrahepatic gallbladder. A case report. |journal=Revista Espanola de Enfermedades Digestivas |date=February 2015 |volume=107 |issue=2 |pages=122–3 |pmid=25659400 |url=http://www.grupoaran.com/mrmUpdate/lecturaPDFfromXML.asp?IdArt=4621099&TO=RVN&Eng=1 |url-status=dead |archive-url=https://web.archive.org/web/20160304040204/http://www.grupoaran.com/mrmUpdate/lecturaPDFfromXML.asp?IdArt=4621099&TO=RVN&Eng=1 |archive-date=March 4, 2016 |df=mdy }}</ref> 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.<ref>{{cite journal|last=Dhulkotia|first=A|author2=Kumar, S |author3=Kabra, V |author4= Shukla, HS |title=Aberrant gallbladder situated beneath the left lobe of liver|journal=HPB|date=March 1, 2002|volume=4|issue=1|pages=39–42|doi=10.1080/136518202753598726|pmid=18333151|pmc=2023911}}</ref><ref>{{cite journal|last1=Naganuma|first1=S.|last2=Ishida |first2=H. |last3=Konno |first3=K. |last4=Hamashima |first4=Y. |last5=Hoshino |first5=T. |last6=Naganuma |first6=H. |last7=Komatsuda |first7=T. |last8=Ohyama |first8=Y. |last9=Yamada |first9=N. |last10=Ishida |first10=J. |last11=Masamune |first11=O.|title=Sonographic findings of anomalous position of the gallbladder|journal=Abdominal Imaging|date=March 6, 2014|volume=23|issue=1|pages=67–72|doi=10.1007/s002619900287|pmid=9437066|s2cid=30176379}}</ref>{{sfn|Gray's Anatomy|2008|p=1187-81}}

An [[anatomical variation]] can occur, known as a [[Phrygian cap (anatomy)|Phrygian cap]], which is an innocuous fold in the fundus, named after its resemblance to the [[Phrygian cap]].<ref name="pmid1950867">{{cite journal | author=Meilstrup JW | author2=Hopper KD | author3=Thieme GA | title=Imaging of gallbladder variants | journal=AJR Am J Roentgenol | volume=157 | issue=6 | pages=1205–8 | date=December 1991 | pmid=1950867 | doi= 10.2214/ajr.157.6.1950867 | url=http://www.ajronline.org/cgi/pmidlookup?view=long&pmid=1950867| url-access=subscription }}</ref>

===Development===
The gallbladder develops from an [[endoderm]]al outpouching of the embryonic gut tube.<ref name= LARSEN2009 /> Early in development, the human embryo has three [[germ layer]]s and abuts an embryonic [[yolk sac]]. During the second week of [[human embryogenesis|embryogenesis]], as the embryo grows, it begins to surround and envelop portions of this sac. The enveloped portions form the basis for the adult gastrointestinal tract. Sections of this [[foregut]] begin to differentiate into the organs of the gastrointestinal tract, such as the [[esophagus]], [[stomach]], and [[intestine]]s.<ref name= LARSEN2009 />

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 [[duodenum]]. By the end of the fourth week, the developing duodenum begins to spout a small outpouching on its right side, the [[hepatic diverticulum]], which will go on to become the [[hepatobiliary system|biliary tree]]. Just below this is a second outpouching, known as the ''cystic diverticulum'', that will eventually develop into the gallbladder.<ref name=LARSEN2009>{{cite book|first=Gary C. |last=Schoenwolf |display-authors=etal|title=Larsen's human embryology|year=2009|publisher=Churchill Livingstone/Elsevier|location=Philadelphia|isbn=978-0-443-06811-9|chapter=Development of the Gastrointestinal Tract|edition=4th}}</ref>

==Function==
{{Bile ducts and pancreas}}
The main functions of the gallbladder are to store and concentrate [[bile]], also called gall, needed for the digestion of fats in food. Produced by the liver, bile flows through small vessels into the larger [[hepatic duct]]s and ultimately through the [[cystic duct]] (parts of the [[biliary tree]]) into the gallbladder, where it is stored. At any one time, {{convert|30|to|60|ml|usoz}} of bile is stored within the gallbladder.<ref name=PHYSIOLOGY2005 />

When food containing fat enters the [[Gastrointestinal tract|digestive tract]], it stimulates the [[secretion]] of [[cholecystokinin]] (CCK) from [[I cell]]s of the duodenum and jejunum. In response to cholecystokinin, the gallbladder rhythmically contracts and releases its contents into the [[common bile duct]], eventually draining into the [[duodenum]]. The bile [[Emulsion|emulsifies]] fats in partly digested food, thereby assisting their absorption. Bile consists primarily of water and [[bile salt]]s, and also acts as a means of eliminating [[bilirubin]], a product of [[hemoglobin]] metabolism, from the body.<ref name=PHYSIOLOGY2005 />

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<ref>{{Cite journal|url=https://www.cghjournal.org/article/S1542-3565(05)00369-1/pdf|title=Biliary Sludge Is Formed by Modification of Hepatic Bile by the Gallbladder Mucosa|last=KO|first=CYNTHIA|date=2005|journal=Clinical Gastroenterology and Hepatology|volume=3|issue=7|pages=672–8|doi=10.1016/s1542-3565(05)00369-1|pmid=16206500|s2cid=27488720 }}</ref> by removal of some water and electrolytes. This is through the [[active transport]] of sodium and chloride ions<ref>{{Cite journal|last1=Meyer|first1=G.|last2=Guizzardi|first2=F.|last3=Rodighiero|first3=S.|last4=Manfredi|first4=R.|last5=Saino|first5=S.|last6=Sironi|first6=C.|last7=Garavaglia|first7=M. L.|last8=Bazzini|first8=C.|last9=Bottà|first9=G.|date=June 2005|title=Ion transport across the gallbladder epithelium|journal=Current Drug Targets. Immune, Endocrine and Metabolic Disorders|volume=5|issue=2|pages=143–151 |pmid=16089346|doi=10.2174/1568008054064805}}</ref> across the epithelium of the gallbladder, which creates an [[osmotic pressure]] that also causes water and other electrolytes to be reabsorbed.<ref name=PHYSIOLOGY2005>{{cite book |last2=Hall |first=Arthur C. |last=Guyton |first2=John E.|title=Textbook of medical physiology|year=2005|publisher=W.B. Saunders|location=Philadelphia|isbn=978-0-7216-0240-0|pages=802–4|edition=11th}}</ref>

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 cholecystectomy has a harmful effect on the risk of right-sided colon cancer.<ref>{{cite journal |vauthors=Mu L, Li W, Ren W, Hu D, Song Y |title=The association between cholecystectomy and the risk of colorectal cancer: an updated systematic review and meta-analysis of cohort studies |journal=Transl Cancer Res |volume=12 |issue=6 |pages=1452–1465 |date=June 2023 |pmid=37434692 |pmc=10331452 |doi=10.21037/tcr-22-2049 |doi-access=free }}</ref>  Another recent study reported a significantly increased total cancer risk, including increased risk of several different types of cancer, after cholecystectomy.<ref>{{cite journal |vauthors=Choi YJ, Jin EH, Lim JH, Shin CM, Kim N, Han K, Lee DH |title=Increased Risk of Cancer after Cholecystectomy: A Nationwide Cohort Study in Korea including 123,295 Patients |journal=Gut Liver |volume=16 |issue=3 |pages=465–473 |date=May 2022 |pmid=35502586 |pmc=9099388 |doi=10.5009/gnl210009 }}</ref>

==Clinical significance==
{{Main|Gallbladder disease}}

===Gallstones===
{{Main|Gallstones}}
[[File:Gallbladder stones.jpg|thumb|left|3D still showing gallstones]]
[[Gallstone]]s form when the bile is [[Saturated solution|saturated]], usually with either [[cholesterol]] or [[bilirubin]].<ref name="MSDGallstones">{{cite web|title=Cholelithiasis - Hepatic and Biliary Disorders - MSD Manual Professional Edition|url=http://www.msdmanuals.com/en-au/professional/hepatic-and-biliary-disorders/gallbladder-and-bile-duct-disorders/cholelithiasis|website=MSD Manual Professional Edition|access-date=18 October 2017|language=en-AU}}</ref> Most gallstones do not cause symptoms, with stones either remaining in the gallbladder or passed along the [[hepatobiliary system|biliary system]].<ref name=DAVIDSONS2010 /> When symptoms occur, severe "colicky" pain in the upper right [[quadrant (abdomen)|quadrant]] of the abdomen is often felt.<ref name="MSDGallstones" /> If the [[cholelithiasis|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.<ref name=DAVIDSONS2010 /> Gallstones are diagnosed using [[ultrasound]].<ref name="MSDGallstones" /> When a symptomatic gallstone occurs, it is often managed by waiting for it to be passed naturally.<ref name=DAVIDSONS2010 /> Given the likelihood of recurrent gallstones, surgery to remove the gallbladder is often considered.<ref name=DAVIDSONS2010 /> 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.<ref name=DAVIDSONS2010 />

===Inflammation===
{{Main|Cholecystitis}}
Known as [[cholecystitis]], inflammation of the gallbladder is commonly caused by obstruction of the duct with gallstones, which is 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 [[cephalosporin]]s and, in severe cases, [[metronidazole]]. Additionally the gallbladder may need to be removed surgically if inflammation has progressed far enough.<ref name=DAVIDSONS2010>{{cite book |editor=Nicki R. Colledge |editor2=Brian R. Walker |editor3=Stuart H. Ralston |title=Davidson's principles and practice of medicine|year=2010|publisher=Churchill Livingstone/Elsevier|location=Edinburgh|isbn=978-0-7020-3085-7|pages=977–984|edition=21st}}</ref>

===Gallbladder removal===
{{Main|Cholecystectomy}}
A [[cholecystectomy]] is a procedure in which the gallbladder is removed. It may be removed because of recurrent gallstones and is considered an [[Elective surgery|elective procedure]]. A cholecystectomy may be an [[open surgery|open]] procedure, or a [[laparoscopic]] one. In the surgery, the gallbladder is removed from the neck to the fundus,<ref name="pmid17761085">{{cite journal | author=Neri V | author2=Ambrosi A | author3=Fersini A | author4=Tartaglia N | author5=Valentino TP | title=Antegrade dissection in laparoscopic cholecystectomy | journal=Journal of the Society of Laparoendoscopic Surgeons | volume=11 | issue=2 | pages=225–8 | year=2007 | pmid=17761085 | pmc=3015719 }}</ref> and so bile will drain directly from the liver into the [[biliary tree]]. About 30 percent of patients may experience some degree of [[indigestion]] following the procedure, although severe complications are much rarer.<ref name=DAVIDSONS2010 /> About 10 percent of surgeries lead to a chronic condition of [[postcholecystectomy syndrome]].<ref>nhs.uk, [http://www.nhs.uk/Conditions/Laparoscopiccholecystectomy/Pages/Riskspage.aspx Complications of a gallbladder removal]</ref>

===Complication===
{{main|Biliary injury|Biloma}}
Biliary injury (bile duct injury) is the traumatic damage of the [[bile ducts]]. It is most commonly an [[iatrogenic]] complication of [[cholecystectomy]] — surgical removal of [[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.<ref>{{citation | author=VK Kapoor | title=Bile duct injury repair: when? what? who? | journal=Journal of Hepato-Biliary-Pancreatic Surgery | year=2007 | volume=14 | issue=5 | pages=476–479 | pmid=17909716 | doi=10.1007/s00534-007-1220-y}}</ref>

Biloma is collection of [[bile]] within the [[abdominal cavity]]. It happens when there is a bile leak, for example after surgery for removing the gallbladder ([[laparoscopic cholecystectomy]]), with an incidence of 0.3–2%. Other causes are biliary surgery, [[liver biopsy]], [[abdominal trauma]], and, rarely, spontaneous perforation.<ref>{{cite book |last=Dolan |first=R.D. |last2=Storm |first2=A.C. |last3=Thompson |first3=C.C. |chapter=Endoscopic management of acute biliary & pancreatic conditions |chapter-url=https://accessmedicine.mhmedical.com/content.aspx?bookid=3204&sectionid=266864223 |editor-last=Friedman |editor-first=S. |editor2-last=Blumberg |editor2-first=R.S. |editor3-last=Saltzman |editor3-first=J.R. |title=Greenberger's CURRENT Diagnosis & Treatment Gastroenterology, Hepatology, & Endoscopy |publisher=McGraw Hill Education |edition=4e |date=2022 |isbn=978-1-260-47343-8 }}</ref>

===Cancer===
{{main|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]]).<ref name=DAVIDSONS2010 /> Gallstones are thought to be linked to the formation of cancer. Other risk factors include large (>1&nbsp;cm) [[gallbladder polyp]]s and having a highly calcified [[porcelain gallbladder|"porcelain" gallbladder]].<ref name=DAVIDSONS2010 />

Cancer of the gallbladder can cause attacks of biliary pain, yellowing of the skin ([[jaundice]]), and weight loss. A large gallbladder may be able to be felt in the abdomen. [[Liver function test]]s may be elevated, particularly involving [[Gamma-glutamyltransferase|GGT]] and [[Alkaline phosphatase|ALP]], with ultrasound and CT scans being considered [[medical imaging]] investigations of choice.<ref name=DAVIDSONS2010 /> Cancer of the gallbladder is managed by removing the gallbladder, however, {{as of|2010|alt=as of 2010|post=,}} the prognosis remains poor.<ref name=DAVIDSONS2010 />

Cancer of the gallbladder may also be found incidentally after surgical removal of the gallbladder, with 1–3% of cancers identified in this way. [[Gallbladder polyp]]s are mostly benign growths or lesions resembling growths that form in the gallbladder wall,<ref>{{cite web|title=Gallbladder Polyps|url=http://www.mayoclinic.com/health/gallbladder-polyps/AN01044|website=MayoClinic|access-date=March 19, 2015}}</ref> and are only associated with cancer when they are larger in size (>1&nbsp;cm).<ref name=DAVIDSONS2010 /> Cholesterol polyps, often associated with [[Cholesterolosis of the gallbladder|cholesterolosis]] ("strawberry gallbladder", a change in the gallbladder wall due to excess [[cholesterol]]<ref>[http://cancerweb.ncl.ac.uk/cgi-bin/omd?strawberry+gallbladder Strawberry gallbladder] – cancerweb.ncl.ac.uk.</ref>), often cause no symptoms and are thus often detected in this way.<ref name=DAVIDSONS2010 />

===Tests===
[[File:Ultrasonography of sludge and gallstones, annotated.jpg|thumb|[[Abdominal ultrasonography]] showing [[biliary sludge]] and [[gallstone]]s]]
Tests used to investigate for gallbladder disease include [[blood tests]] and [[medical imaging]]. A [[full blood count]] may reveal an increased white cell count suggestive of inflammation or infection. Tests such as [[bilirubin]] and [[liver function tests]] may reveal if there is inflammation linked to the biliary tree or gallbladder, and whether this is associated with inflammation of the liver, and a [[lipase]] or [[amylase]] may be elevated if there is [[pancreatitis]]. Bilirubin may rise when there is obstruction of the flow of bile. A [[CA 19-9]] level may be taken to investigate for cholangiocarcinoma.<ref name=DAVIDSONS2010 />

An [[ultrasound]] is often the first [[medical imaging]] test performed when gallbladder disease such as gallstones are suspected.<ref name=DAVIDSONS2010 /> An [[abdominal X-ray]] or [[CT scan]] is another form of imaging that may be used to examine the gallbladder and surrounding organs.<ref name=DAVIDSONS2010 /> Other imaging options include MRCP ([[magnetic resonance cholangiopancreatography]]), [[Endoscopic retrograde cholangiopancreatography|ERCP]] and percutaneous or intraoperative [[cholangiography]].<ref name=DAVIDSONS2010 /> A [[cholescintigraphy]] scan is a [[nuclear imaging]] procedure used to assess the condition of the gallbladder.<ref>{{cite web|title=HIDA scan - Overview|url=https://www.mayoclinic.org/tests-procedures/hida-scan/home/ovc-20200578|website=Mayo Clinic|access-date=18 October 2017|language=en}}</ref>

==Other animals==
Most [[vertebrate]]s have gallbladders, but the form and arrangement of the bile ducts may vary considerably. In many species, for example, there are several separate ducts running to the intestine, rather than the single common bile duct found in humans. Several species of [[mammal]]s (including [[horse]]s, [[deer]], [[rodent]]s, and [[lamini|laminoids]]),<ref>C. Michael Hogan. 2008. [http://globaltwitcher.auderis.se/artspec_information.asp?thingid=42654 ''Guanaco: Lama guanicoe'', GlobalTwitcher.com, ed. N. Strömberg] {{webarchive|url=https://web.archive.org/web/20110304004355/http://globaltwitcher.auderis.se/artspec_information.asp?thingid=42654 |date=March 4, 2011 }}</ref><ref>{{cite journal | last1 = Higashiyama | first1 = H | last2 = Sumitomo | first2 = H | last3 = Ozawa | first3 = A | last4 = Igarashi | first4 = H | last5 = Tsunekawa | first5 = N | last6 = Kurohmaru | first6 = M | last7 = Kanai | first7 = Y | year = 2016 | title = Anatomy of the Murine Hepatobiliary System: A Whole-Organ-Level Analysis Using a Transparency Method | journal = The Anatomical Record | volume = 299 | issue = 2| pages = 161–172 | doi = 10.1002/ar.23287 | pmid = 26559382 | doi-access = free }}</ref> several species of [[bird]]s (such as pigeons and some [[psittacine]] species), [[lamprey]]s and all [[invertebrate]]s do not have a gallbladder.<ref name=VB>{{cite book |author=Romer, Alfred Sherwood|author2=Parsons, Thomas S.|year=1977 |title=The Vertebrate Body |publisher=Holt-Saunders International |location= Philadelphia, PA|page= 355|isbn= 978-0-03-910284-5}}</ref><ref>{{Cite journal|date=2010|title=Complex Evolution of Bile Salts in Birds|journal= The Auk|doi=10.1525/auk.2010.09155 |doi-access=free |pmc=2990222|last1=Hagey|first1=L. R.|last2=Vidal|first2=N.|last3=Hofmann|first3=A. F.|last4=Krasowski|first4=M. D.|volume=127|issue=4|pages=820–831|pmid=21113274}}</ref>

The bile from several species of bears is used in [[traditional Chinese medicine]]; [[bile bear]]s are kept alive in captivity while their bile is extracted, in an industry characterized by [[animal cruelty]].<ref>{{cite web|last1=Actman|first1=Jani|title=Inside the Disturbing World of Bear-Bile Farming|url=https://news.nationalgeographic.com/2016/05/160505-asiatic-bear-bile-trade-laos/|archive-url=https://web.archive.org/web/20160505140128/http://news.nationalgeographic.com/2016/05/160505-asiatic-bear-bile-trade-laos/|url-status=dead|archive-date=May 5, 2016|website=National Geographic|access-date=23 October 2017|date=5 May 2016}}</ref><ref>{{cite news|last1=Hance|first1=Jeremy|title=Is the end of 'house of horror' bear bile factories in sight?|url=https://www.theguardian.com/environment/radical-conservation/2015/apr/09/bear-bile-china-synthetic-alternative|newspaper=The Guardian|access-date=23 October 2017|date=9 April 2015}}</ref>

==History==
Depictions of the gallbladder and biliary tree are found in [[Babylon]]ian models found from 2000 BCE, and in ancient [[Etruscan civilization|Etruscan]] model from 200 BCE, with models associated with divine worship.<ref name="Eachempati2015" />

Diseases of the gallbladder are known to have existed in humans since antiquity, with gallstones found in the mummy of Princess Amenen of [[Thebes, Egypt|Thebes]] dating to 1500 BCE.<ref name="Eachempati2015" /><ref name="Blumgart2012">{{cite book|last1=Jarnagin|first1=William R.|title=Blumgart's Surgery of the Liver, Pancreas and Biliary Tract E-Book: Expert Consult - Online|date=2012|publisher=Elsevier Health Sciences|isbn=978-1-4557-4606-4 |page=511|url=https://books.google.com/books?id=neZGIB-xyVkC&pg=PA511 }}</ref> Some historians believe the death of [[Alexander the Great]] may have been associated with an acute episode of cholecystitis.<ref name="Eachempati2015" /> 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,<ref name="Blumgart2012" /> particularly in the last two centuries.<ref name="Eachempati2015">{{cite book|last1=Eachempati|first1=Soumitra R.|last2=II|first2=R. Lawrence Reed|title=Acute Cholecystitis|date=2015|publisher=Springer|isbn=978-3-319-14824-3 |pages=1–16|url=https://books.google.com/books?id=oKFnCgAAQBAJ&pg=PA1 }}</ref>

The first descriptions of gallstones appear to have been in the [[Renaissance]], perhaps because of the low incidence of gallstones in earlier times owing to a diet with more cereals and vegetables and less meat.<ref name="Bateson2012">{{cite book|last1=Bateson|first1=M. C.|title=Gallstone Disease and its Management|date=2012|publisher=Springer  |isbn=978-94-009-4173-1 |pages=1–2|url=https://books.google.com/books?id=zNdeBAAAQBAJ&pg=PA1 }}</ref> Anthonius Benevinius in 1506 was the first to draw a connection between symptoms and the presence of gallstones.<ref name="Bateson2012" /> [[Ludwig Georg Courvoisier]], after examining a number of cases in 1890 that gave rise to the [[eponymous]] [[Courvoisier's law]], stated that in an enlarged, nontender gallbladder, the cause of [[jaundice]] is unlikely to be gallstones.<ref name="Eachempati2015" />

The first surgical removal of a gallstone (cholecystolithotomy) was in 1676 by physician Joenisius, who removed the stones from a spontaneously occurring [[biliary fistula]].<ref name="Eachempati2015" /> Stough Hobbs in 1867 performed the first recorded [[cholecystotomy]],<ref name="Bateson2012" /> although such an operation was in fact described earlier by French surgeon [[Jean Louis Petit]] in the mid eighteenth century.<ref name="Eachempati2015" /> German surgeon [[Carl Langenbuch]] performed the first cholecystectomy in 1882 for a sufferer of cholelithiasis.<ref name="Blumgart2012" /> Before this, surgery had focused on creating a [[fistula]] for drainage of gallstones.<ref name="Eachempati2015" /> Langenbuch reasoned that given several other species of mammal have no gallbladder, humans could survive without one.<ref name="Eachempati2015" />

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.<ref name="Blumgart2012" /> It was only in the mid and late parts of the twentieth century that medical imaging techniques such as use of [[contrast medium]] and [[CT scan]]s were used to view the gallbladder.<ref name="Eachempati2015" /> The first [[laparoscopy|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.<ref name="Reynolds2001">{{cite journal|last1=Reynolds|first1=Walker|title=The First Laparoscopic Cholecystectomy|journal=Journal of the Society of Laparoendoscopic Surgeons|date=January–March 2001 |volume=5|issue=1|pages=89–94|pmc=3015420|pmid=11304004}}</ref>

==Society and culture==
To have "gall" is associated with bold, belligerent behaviour, whereas to have "bile" is associated with sourness.<ref>{{Cite book |last=Lifang |first=Qu |title=Chinese Medicine Psychology: A Clinical Guide to Mental and Emotional Wellness. |publisher=Jessica Kingsley Publishers |year=2020 |isbn=978-1-78775-276-4 }}</ref>

In the [[Traditional Chinese medicine|Chinese medicine]], the gallbladder ({{linktext|lang=zh|膽}}) is associated with the [[Wuxing (Chinese philosophy)|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 [[idiom]]s, including using terms such as "a body completely [of] gall" ({{lang|zh-Hant|渾身是膽}}) to describe a forward person, and "single, alone gallbladder hero" ({{lang|zh-Hant|孤膽英雄}}) to describe a lone hero, or "they have a lot of gall to talk like that".<ref name=YU2003>{{cite journal|last=Yu|first=Ning|title=Metaphor, Body, and Culture: The Chinese Understanding of Gallbladder and Courage|journal=Metaphor and Symbol|date=January 1, 2003|volume=18|issue=1|pages=13–31|doi=10.1207/S15327868MS1801_2|s2cid=143595915}}</ref>

In the [[Zangfu]] theory of [[Chinese medicine]] it is an extraordinary Fu or [[Yin and yang|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.<ref name=YU2003 />

==See also==
{{Portal|Medicine}}
* [[Enterohepatic circulation]]
* [[Gallbladder flush]]

==References==
{{reflist|30em}}

;Books
* {{cite book|veditors = Standring S, Borley NR|others=Brown JL, Moore LA|title=Gray's Anatomy : The Anatomical Basis of Clinical Practice|date=2008|publisher=Churchill Livingstone|location=London|isbn=978-0-8089-2371-8|edition=40th|ref={{harvid|Gray's Anatomy|2008}}}}

==External links==
{{Commons category|Gallbladder}}
* [http://www.innerbody.com/image/dige02.html Diagram of Human Stomach and Gallbladder]&nbsp;– Human Anatomy Online dd, MyHealthScore.com

{{Accessory digestive glands}}
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[[Category:Gallbladder| ]]
[[Category:Abdomen]]
[[Category:Animal anatomy]]
[[Category:Organs (anatomy)]]
[[Category:Digestive system]]