Hepatobiliary stone disease is a primary hepatobiliary stone, usually called intrahepatic bile duct stone, which originates from the left and right hepatic ducts above the confluence of the hepatic ducts and is located in the bile ducts of all branches of the liver.
Hepatobiliary stones are mainly bile pigment stones, and biliary tract infection and bile stasis are the main pathogenic mechanisms. Hepatobiliary stones can be diffusely distributed or confined to one site, generally in the left outer lobe and right posterior lobe, which may be related to the greater curvature of the bile ducts and easy bile accumulation there.
The diagnosis of hepatic bile duct stone disease.
The diagnosis is mainly based on clinical manifestations, imaging and laboratory tests.
1.Clinical manifestations
Hepatobiliary stones have an insidious onset and a long course. In some patients, serious complications such as biliary cirrhosis, hepatic atrophy, portal hypertension, septic cholangitis, or even hepatobiliary duct cancer may occur at the first visit. The clinical manifestations vary according to the length of the disease and the severity of the lesion. In severe cases, abdominal pain, high fever and jaundice may occur, which can be life-threatening if not treated promptly. Late stage stones can cause intrahepatic bile duct obstruction, which may lead to atrophy of the liver segment, lobe or even the whole liver, biliary cirrhosis, liver abscess and other manifestations.
According to its clinical manifestations, hepatic bile duct stone disease is often classified into four types.
Quiet type: Patients have no obvious symptoms or only have epigastric pain and discomfort, often discovered during physical examination.
obstructive type: the main manifestation is biliary obstruction, with intermittent or persistent jaundice, pain and discomfort in the right upper abdomen, as well as loss of appetite and diarrhea.
Cholangitis type: with recurrent episodes of cholangitis as the main manifestation. It is characterized by varying degrees of abdominal pain, fever and chills, jaundice, often accompanied by pressure pain in the right upper abdomen, percussion pain in the liver area, hepatomegaly with tenderness and other signs. Severe acute septic cholangitis may present with sepsis, shock and coma.4. Sclerotic type: late in the course of the disease, biliary cirrhosis and manifestations of portal hypertension may appear, such as hepatosplenomegaly, persistent severe jaundice, ascites, hypoproteinemia, esophagogastric fundic varices, and gastrointestinal bleeding.
2.Imaging examination
At present, imaging examinations including ultrasound, CT, MRI, etc. can not only clarify the diagnosis, but also understand the distribution of intrahepatic stones, the presence of atrophy in the liver, the sites of dilatation and stenosis of bile ducts inside and outside the liver, as well as the presence of infection, tumor, portal hypertension and other complications, which provide the basis for determining the treatment plan. Some invasive tests such as cholangiography and cholangioscopy are only performed when necessary and are not used as routine tests.
Ultrasound diagnosis of hepatobiliary stones is accurate, easy to perform and inexpensive, and is the preferred method of examination. The correct rate is 70% to 80%, and intraoperative ultrasound can improve the diagnosis rate of hepatobiliary stones up to 91% and reduce the rate of residual stones after surgery. Ultrasonography has its limitations, firstly, operator experience affects the correct diagnosis rate, secondly, when combined with biliary tract infection, bile duct pneumatosis or tumor, the diagnosis will be difficult, thirdly, it is difficult to show the bile duct stricture site and possible combined extrahepatic lower bile duct stones, it is not as intuitive as CT and MRI, and it is difficult to be used as the whole basis for surgical planning.
CT can usually show the distribution of stones in the intrahepatic bile ducts, dilatation of the biliary system, atrophy of the liver parenchyma and splenomegaly and esophagogastric fundus varices due to portal hypertension, which can provide a reliable basis for surgical planning. However, CT is more difficult to diagnose some fine stones and stones that cannot be visualized by X-ray. With the rapid development of computer science in recent years, the use of digital three-dimensional reconstruction technology can simulate the human liver and provide a reference for determining the extent of lesions and the choice of surgical approach. It is also possible to simulate surgical resection on the reconstructed 3D model and observe the resection effect, so as to select the best treatment plan for hepatobiliary stones.
A unique advantage of MRI is the MRCP technique. MRCP is simple, non-invasive, and can show the site, number, size, and degree of bile duct dilatation or stenosis of bile duct stones from multiple directions, and its sensitivity, specificity, and accuracy are getting better, but it is not as clear and accurate as direct bile duct imaging for narrow bile ducts.
ERCP (transendoscopic cholangiopancreatography) and PTC (percutaneous transluminal cholangiography) are the traditional methods for the diagnosis of hepatobiliary stones, but they are not used as a routine diagnostic tool for bile duct stones because of their invasive nature, but ERCP and PTC are often used for the treatment of hepatobiliary stones and bile duct drainage at the same time as diagnosis.
Although hepatobiliary stones can be easily diagnosed by imaging, the inflammatory changes of the bile ducts in the hilar region caused by stones are more difficult to distinguish from hilar cholangiocarcinoma, which is sometimes difficult to identify even during surgery.
3.Laboratory examination
There is no specific detection index for hepatic bile duct stones. The main purpose of laboratory examination is to understand liver function, coagulation function and general nutritional status. It is an important part of preoperative evaluation.
Surgical treatment of hepatobiliary duct stone disease
Surgical treatment is still the main means of hepatobiliary stones, and it is usually recognized that the following three principles should be followed: (1) remove the stones and lesions as much as possible; (2) release the obstruction and correct the stricture; (3) unblock the drainage and prevent recurrence. In our opinion, ensuring adequate postoperative liver function is another important principle that must be followed. The main surgical methods include: hepatectomy, high bile duct dissection and lithotomy, transhepatic parenchymal bile duct dissection and lithotomy, bile-intestinal anastomosis and liver transplantation. The selection of the surgical plan must be individualized, depending on the number and distribution of hepatobiliary stones, the location and degree of hepatic stenosis, the pathological changes in the liver, the functional status of the liver and the patient’s general condition. One of the debated issues is whether surgery is needed for asymptomatic hepatobiliary stones. In most cases, serious complications will occur with the progression of the disease and the development of the lesion, therefore, for patients with a clear diagnosis but not obvious symptoms, aggressive surgical treatment is preferable to prevent further liver damage.
1. Hepatectomy
It can be divided into regular hepatectomy and irregular partial hepatectomy. Irregular partial hepatectomy can be used in cases where the lesion is small, but the stones are more concentrated and distributed in a smaller area, or the liver function is poor, which does not allow the implementation of regular resection, with simple surgical operation and few postoperative complications. However, the basic pathological change of hepatic bile duct stones is the regular regional distribution of stones along the diseased bile ducts, and the involved liver is also the corresponding liver lobe or liver segment, this characteristic determines that the liver tissue resection for hepatic bile duct stones should be more reasonable with regular resection. It has been proved that irregular resection for regional hepatic bile duct stones in diseased liver segments or diffuse hepatic bile duct stones in hepatic atrophy foci may lead to residual stones or recurrence due to insufficient resection scope, which may cause recurrent bile duct infections and necessitate reoperation. Therefore, regular hepatectomy should be the preferred means of hepatobiliary stone lesion removal. For multiple stones in both lobes of the liver, hepatic resection should be selected for appropriate patients, and combined with intraoperative choledochoscopic stone extraction, a high stone removal rate and five-year survival rate can be obtained.
The most important principle of hepatectomy for hepatobiliary stones is to ensure that adequate liver function is preserved postoperatively. The Child-Pugh score is often used preoperatively to select cases that meet the surgical indications. Newer studies have shown that liver function reserve in patients with hepatic bile duct stones assessed by indocyanine green retention test can more effectively predict and avoid postoperative liver failure.
2. High biliary ductotomy for stone extraction
High choledochotomy is performed by extending the common bile duct incision to the confluence of the hepatic ducts, removing the stones in each branch through the left and right hepatic duct openings under direct vision and relieving the hepatic bile duct strictures, and draining the remaining small stones with T-tube.
However, blind instrumentation via the extrahepatic bile duct route often leads to a high rate of residual stones and requires the use of physical lithotripsy such as intraoperative ultrasound, intraoperative cholangioscopy, intraoperative cholangiography and laser to improve the surgical outcome. Intraoperative ultrasound can clearly determine the distribution of stones in the liver and guide stone extraction. Intraoperative choledochoscopy can directly observe the stone condition and bile duct wall lesions, and remove stones with lithotripsy mesh baskets, lithotripsy instruments and balloon catheters under the scope, which overcomes the blind area of conventional instruments for stone extraction, visualizes the site of bile duct obstruction, avoids bile duct injury, and reduces the residual stone rate. Some studies have shown that intraoperative use of ultrasound-guided choledochoscopy is more effective than using choledochoscopy without ultrasound guidance, with stone residual rates of 5.4% and 19%, respectively. For large stones or embedded stones that are difficult to be removed directly, they can be removed by gas bomb, liquid electric, laser or ultrasonic lithotripsy.
3. Transhepatic parenchymal resection of bile ducts
The method of transhepatic parenchymal incision bile duct extraction is simple, and the operator can remove the stone under direct vision by incising the liver parenchyma where the stone is touched on the liver surface, which avoids the disadvantage of long and blind trip of transhepatic common bile duct incision to remove the stone, and helps to remove all the stones. However, transhepatic parenchymal resection cannot solve the problem of bile duct patency and drainage, and cannot prevent the recurrence of hepatobiliary stenosis. Moreover, there are more complications of hepatic parenchymal resection, such as bile leakage, subdiaphragmatic abscess, etc. The complication rate can reach 28.6%, and the recurrence rate of stones is higher, with a 5-year recurrence rate of 34.3%.
4. Biliary (hepatic) intestinal anastomosis
Biliary (hepatic) intestinal anastomosis is often used as an additional procedure in the surgical treatment of hepatobiliary stones, with the aim of relieving bile duct strictures, allowing bile drainage and reducing the residual stone rate. Postoperative reflux causing different degrees of cholangitis is one of the main drawbacks of this procedure. The commonly used biliary (hepatic) intestinal anastomosis is the biliary (hepatic) jejunojejunostomy Roux-en-Y. For patients with residual stones and a high probability of recurrence, we usually interpose jejunal collaterals between the anastomosis and the skin, and after the procedure, a skin incision can be made to remove the stones with a choledochoscope through the collaterals.
5. Liver transplantation
It is suitable for patients with hepatic bile duct stones that have caused severe biliary cirrhosis and liver failure. The treatment effect is complete, but it is difficult to carry out widely because of the extreme shortage of donor and high cost.
III. Non-surgical treatment of hepatobiliary duct stones
Although surgery is currently the best way to treat hepatobiliary stones, if the patient’s systemic condition or local lesions do not allow the implementation of surgery, non-surgical treatment is the only option.
1.Cholangioscopy for stone extraction
Cholangioscopy is widely used in the treatment of hepatobiliary stones. Percutaneous transhepatic percutaneous choledochoscopy and transoral choledochoscopy for stone extraction are suitable for patients who are not suitable for surgical treatment. It has been estimated that the rates of complete stone removal using hepatectomy, percutaneous hepatic puncture choledochoscopy and transoral choledochoscopy are 83.3%, 63.9% and 57.1%, respectively. Postoperative choledochoscopy and treatment have become routine for the postoperative treatment of hepatobiliary stones. The best therapeutic effect can be obtained by removing the residual intrahepatic bile duct stones through the T-tube sinusoidal tract, using lithotripter or lithotripter basket under the scope, and combining with various physical lithotripsy methods such as laser.
2.Lithotripsy therapy
Oral administration of certain drugs to dissolve gallstones is an ideal treatment, but unfortunately, there is no exact and effective method so far, despite years of research at home and abroad. At present, there are two kinds of oral lithotripsy drugs most commonly used in clinical practice: goose deoxycholic acid (CDCA) and ursodeoxycholic acid (UDCA). However, these two drugs are not effective for patients with hepatobiliary stones mainly bilirubin stones. Some domestic reported Chinese herbal medicines such as compound orange peel oil emulsion can dissolve bilirubin stones and rely on T-tube or PTCD, ERCP perfusion to treat hepatobiliary stones with good results, but there is still a lack of sufficient evidence-based medical evidence.
With the advancement of technology, more treatment options for hepatobiliary stone disease will surely be available. However, at this stage, surgery is still the main treatment option. The choice of surgical approach for different patients and how to improve the therapeutic effect of surgery need more practice and conclusion by surgeons.