The gallbladder is located under the surface of the liver. It has four regions: the fundus, body, infundibulum, and the neck. The fundus is the round, blind edge of the organ. It leads to the body. The infundibulum is the tapering area of the gallbladder between the body and neck. The neck of the gallbladder is 5 to 7 mm in diameter and often forms an S-shaped curve. The neck leads to the gallbladder duct called the cystic duct. The right and left hepatic ducts from the right and left parts of the liver join to from the common hepatic duct, which in turn joins with the cystic duct to form the common bile duct (CBD). All the ducts look like branches of a tree and hence called the biliary tree.
Calculus (stone) disease of the biliary tract is the general term applied to diseases of the gallbladder and biliary tree that are a direct result of gallstones. Gallstone disease is the most common disorder affecting the biliary system. Gallstones (choleliths) are solid masses formed from bile precipitates. These “stones” may occur in the gallbladder or the biliary tract (ducts leading from the liver to the small intestine).
There are two types of gallstones: A. Cholesterol . B. Pigment.
- Cholesterol stones are yellow-green and are primarily made of hardened cholesterol. Cholesterol stones, predominantly found in women and obese people, are associated with bile supersaturated with cholesterol. They account for 80% of gallstones and are more commonly involved in obstruction and inflammation.
- Pigment stones may be black or brown stones.
- Black pigment stones are made of pure calcium bilirubinate. These gallstones typically remain in the gallbladder due to pooling of bile or excess unconjugated bilirubin.
- Brown pigment stones are composed of calcium salts of unconjugated bilirubin often located in the bile ducts.
PROCESS OF FORMATION:
Gallstones form when the bile, that is stored in the gallbladder, hardens into pieces of solid material. This process requires three conditions.
- The first is that the bile must supersaturate with cholesterol.
- The second condition is accelerated cholesterol transition from liquid to crystal.
- The third condition for gallstone formation is gallbladder hypomotility, a condition in which crystals to remain in the gallbladder long enough to form stones.
Gallstone disease may not be symptomatic until there are complications. Often, these complications are caused by inflammation, infection, or ductal obstruction. About 70% to 80% of symptomatic patients complain of severe pain due to spasm (called biliary colic) resulting from transient obstruction of the cystic duct by a stone. This pain is felt in the upper abdomen or right part of the upper abdomen. It is sudden and severe accompanied by vomiting and excessive sweating. In addition, there is nausea, gas production, and yellowish color of skin with clay-colored stools.
- Gallbladder inflammation (cholecystitis).
- Bile duct stones (choledocholithiasis).
- Bile duct inflammation (cholangitis).
- Pancreas inflammation (pancreatitis).
- Abnormal communication between the gallbladder and the small intestine(cholecystenteric fistulae)
PREVALENCE OF GALLBLADDER DISEASE:
- Increasing age.
- More women are affected than men.
- Drugs like contraceptive pills and estrogen replacement.
- Greater incidence in the white population.
- Obesity is a risk factor (more in central obesity and with BMI of >30).
- Sedentary lifestyle.
Liver function tests (in gallstone complications), complete blood count (in acute cholecystitis), and amylase and lipase enzyme tests (in case of pancreatitis) are the usual tests done.
- Abdominal ultrasonography (USG scan) because of its high specificity and sensitivity is the best noninvasive test to detect gallstones, fluid around the gallbladder, gas in the gallbladder, and stone obstruction of the bile duct.
- CT scan to detect complications of gallstones such as pericholecystic fluid, gas in the gallbladder wall, gallbladder perforations, and abscesses.
- Magnetic resonance imaging (MRI) and magnetic resonance cholangiopancreatography (MRCP) assess biliary obstruction and pancreatic ductal anatomy.
- Cholescintigraphy employs the use of an intravenous radioactive material to detect a nonfunctioning gallbladder (as in acute cholecystitis)
- Endoscopic Retrograde Cholangiopancreatography (ERCP) is the gold standard for the detection of gallstones.
- Endoscopic ultrasonography (EUS) is a highly technical, low-risk diagnostic procedure that allows imaging of the common bile duct and the gallbladder.
The treatment options for symptomatic gallstones are:
Several medical treatment options are available for symptomatic gallstones. Ursodeoxycholic acid and HMG CoA reductase inhibitors both suppress de-novo hepatic cholesterol synthesis. This results in the secretion of under saturated bile, facilitating stone dissolution.
Cholecystectomy is the only definitive treatment for symptomatic gallstones.
- While open cholecystectomy was the standard surgical option for patients in the past, laparoscopic cholecystectomy has replaced the open procedure as the treatment option of choice in all but a few instances.
- Laparoscopic cholecystectomy is a minimally invasive procedure in which the surgeon makes a few small incisions in the abdomen and uses a small video camera to magnify the organs of the abdominal cavity. Using the video monitor to guide his actions, the surgeon identifies, isolates, and removes the gallbladder from its connections to the liver and bile ducts through the laparoscope. The procedure does not involve a large abdominal incision and results in less pain, shorter hospital stay, and fewer days missed from work.
Extracorporeal Shock Wave Lithotripsy:
This is a nonsurgical alternative to manage gallstones in patients not fit for surgery. No general anesthesia is required, and the patient may be managed on an outpatient basis. This method employs high-energy sound waves that produce shock waves. These shock waves are transmitted through water and tissue and have the ability to fragment gallstones.
Gallbladder polyps are growths that protrude from the lining of the inside of the gallbladder. Polyps can be cancerous, but they rarely are. About 95 percent of gallbladder polyps are benign. The size of a gallbladder polyp can help predict whether it's cancerous (malignant) or noncancerous (benign).
Small gallbladder polyps that are less than 1/2 inch (about 10 millimeters (mm)) in diameter are unlikely to be cancerous.
Larger polyps larger than 1/2 inch (about 10 mm) in diameter are more likely to be cancerous, and those larger than about 3/4 of an inch (18 mm) in diameter may pose a significant risk of being malignant.
Treatment of larger gallbladder polyps includes surgical removal of the gallbladder (cholecystectomy).
Tags: Gallstone , Disease , calculus , Kidney Stones , gall bladder