What are hepatobiliary stones?
Hepatobiliary stones are stones in the bile ducts above the bifurcation of the common hepatic duct. They account for 16% of the 11,342 cases of gallstone disease investigated nationwide. Hepatobiliary stones can be accompanied by hepatobiliary stenosis. According to the analysis of 4197 cases of surgical treatment of hepatobiliary stones nationwide, the incidence of hepatobiliary stenosis was 24.28% on average and up to 41.94% on average in the highest region. More than 46% of the cases operated for the second time were accompanied by hepatobiliary stenosis, and the incidence of stenosis was directly proportional to the reoperation. The nature of hepatobiliary stones is mostly pigmented mixed stones containing higher amounts of calcium bilirubin, and the pathogenesis may be related to biliary tract infection, bile retention and biliary parasites. Currently, due to the widespread development and popularity of ultrasound, PTC, ERCP, CT and ultrasound-guided PTC, intrahepatic bile duct stones and strictures can be diagnosed more quickly and a full picture of the changes in the course of the biliary system can be obtained from imaging, but at present, the treatment effect of hepatic bile duct stones is still not satisfactory, and the residual stone rate after surgery is still as high as 30.4%. Therefore, the treatment of this disease is still far from a fundamental solution, and some cases have become complicated and difficult to treat, and many topics still need further research and discussion.
Can cholangiocarcinoma be caused by bile duct stones?
Whether bile duct stones can cause bile duct cancer and whether there is a causal relationship between them is one of the main concerns of bile duct stone patients and their families. The long-term stimulation of bile ducts by bile duct stones can cause inflammatory changes in the mucous membrane of bile duct walls and even atypical proliferation of mucous membrane cells. Therefore, it is generally believed that bile duct stones may have some relationship with bile duct cancer. However, it is still a controversial issue whether gallstone disease causes cholangiocarcinoma or cholangiocarcinoma is complicated by gallstones in the process of its development. There are many patients with bile duct stones who do not develop bile duct cancer despite the long duration of the disease. Therefore, patients with bile duct stones do not need to be overly nervous, but of course, the possibility of cancer cannot be ignored, and they should go to hospital for treatment in time.
What pathological changes can be caused by hepatic and bile duct stones?
The pathological changes of hepatic bile duct stones can be summarized into 3 aspects.
(1) Gallstone obstruction leads to lesions mainly of proliferative cholangitis. The main manifestations are thickening of the wall of the hepatobiliary duct containing stones, enlargement of the lumen of the hepatobiliary duct and its proximal end, and the formation of segmental cystic dilatation where most stones accumulate. Between the dilated segments or after an isolated large stone, the ductal diameter of the bile duct is relatively narrow. The lining of the stone-bearing bile ducts and their adjacent bile ducts is not smooth due to a decrease in smooth muscle and elastic fibers and proliferation of fibrous tissue. The microscopic changes are chronic proliferative cholangitis with increased connective tissue in the wall of the bile duct, hyperplasia of the intramural ductal glands, and hyperplasia of the vesicular glands around the bile duct that secrete acidic mucus and plasma surrounded by fibrous bundles. The more stones contained in the bile duct, the more vesicular glands surrounding the bile duct wall. Proliferative cholangitis is a precursor lesion to bile duct stricture and carcinoma.
(2) Lesions of recurrent purulent cholangitis. This lesion is mainly caused by recurrent acute purulent infection of the bile ducts due to stones. The mucosa of the bile ducts is seen to be congested and edematous with hemorrhagic spots by the naked eye or cholangioscopy, and the mucosa is necrotic and ulcerated at severe inflammation, covered with pus moss. The openings of the affected hepatic bile ducts were lip-like due to mucosal edema, making the round mouth of the ducts slit-like. Microscopically, the bile ducts were seen to have ductal ulcer formation and purulent inflammatory changes on the basis of chronic proliferative cholangitis, with granulation tissue surrounding the ulcers, and the bile ducts also showed acute inflammatory changes around the bile ducts. The mucosal ulcers were fibrous repair with a majority of epithelioid cell granulomas in the wall, and megakaryocytes and cell fusion were common within the granulomas. Further deterioration of acute purulent cholangitis may result in the formation of liver abscess due to total necrosis of the bile duct wall and spread of infection to the liver tissue, and intrahepatic biliary hemorrhage due to abscess erosion of intrahepatic vessels. Bacteria and bile sandstone enter into the damaged blood vessels and serious secondary diseases such as sepsis or septicemia may occur.
(3) Damage to liver parenchyma. With the recurrence of septic cholangitis and the polymerization of bilirubin complexes, the volume and number of stones further increase, thus forming a vicious cycle of stone obstruction – retrograde infection – inflammatory stenosis of the hepatic bile duct – regeneration of stones. With the expansion of intrahepatic bile duct stone invasion, the damage to the liver parenchyma gradually increases, and the lesion may progress from collapse, fibrosis and atrophy of liver lobules to fibrosis and atrophy of liver segments and lobes. The remaining hepatic tissues show compensatory hyperplasia, resulting in asymmetric hepatomegaly of the liver. As a result of long-term obstruction by bilateral hepatic bile duct stones, biliary hepatic sclerosis and portal hypertension can occur, with splenomegaly and esophageal varices. Upper gastrointestinal bleeding and hepatic coma are the causes of death in patients with advanced disease.
Why can bile duct stones cause biliary stricture?
The basic pathological change of bile duct stones is obstruction of the bile ducts, on the basis of which repeated and progressive inflammatory infections of the bile ducts can occur. On the one hand, the stones themselves can cause mechanical damage to the inner wall of the bile duct; on the other hand, more importantly, repeated infections can cause damage to the bile duct wall. With the repeated process of injury and repair, the bile duct wall tissue is replaced by inflammatory scar tissue and further contractures occur, resulting in biliary strictures.
What are the types of hepatobiliary stones and strictures?
There are two common typing methods for hepatic bile duct stones and strictures: one is the Japanese typing and the other is the Tsunoda typing.
(1) Japanese typing: In 1985, a new typing method for hepatobiliary stones and strictures was proposed in Japan. According to the location of the stone, it is divided into intrahepatic type (type I), which has stones in the intrahepatic bile duct, and intra- and extrahepatic type (type IE), which has stones in both the internal and external bile duct. According to the location of the stones in the left and right hepatic lobes, they are further divided into left type (L type), right type (R type) and right and left type (LR type). According to the degree of bile duct stenosis, they are S0 (no stenosis), S1 (mild stenosis) and S2 (severe stenosis). According to its location, it was divided into terminal stenosis, central stenosis, hepatic duct stenosis, common hepatic duct stenosis and common bile duct stenosis. The bile ducts are also classified into D0 (no dilatation), D1 (mild dilatation), and D2 (severe dilatation) according to their degree of dilatation. According to its location, it is divided into terminal dilation, central dilation, hepatic duct dilation and common bile duct dilation.
(2), Tsunoda typing: Tsunoda et al. are typed according to the site of stone presence, bile duct stricture and the presence or absence of bile duct dilatation.
Type I: No significant dilatation of intrahepatic bile ducts, with small stones and biliary sludge.
Type II: generalized dilatation of intrahepatic bile ducts, usually with stenosis of the lower end of the common bile duct.
Type I and type II intrahepatic stones are caused by extrahepatic factors, so they are called secondary intrahepatic bile duct stones.
Type III: One side of the intrahepatic bile duct has single or multiple cystic localized dilatation, often accompanied by left or right intrahepatic bile duct stenosis.
Type IV: the same as type III, but the lesions are located in the bilateral liver lobes.
Types III-IV are caused by intrahepatic factors, so they are called primary intrahepatic bile duct stones.
Bile duct stenosis is a limited narrowing between the upper and lower bile duct internal diameter, and the boundary between mild and severe stenosis is 2 mm. if there is bile duct dilatation and the two are connected, the lumen internal diameter of the stenosis is larger than the normal bile duct diameter, and such stenosis is called relative stenosis. The cutoff between mild and severe dilatation of the intrahepatic bile ducts is a luminal diameter of more than 10 mm.
What complications can intrahepatic bile duct stones cause?
(1) Acute septic cholangitis. When hepatic bile duct stones are complicated by acute obstructive purulent cholangitis, regardless of the site of stone obstruction, toxemia and infectious shock can occur and lead to multiple organ failure, including liver, kidney, lung, heart and brain.
(2) Liver abscess and bronchobiliary fistula. Liver abscess can be formed on the basis of recurrent acute obstructive purulent cholangitis, and its clinical symptoms are similar to those of acute purulent cholangitis. When the abscess penetrates to the lung, a bronchobiliary fistula is formed, and the clinical manifestation is coughing and coughing up pus, at which time the symptoms of severe infection will be quickly reduced.
(3) Bile duct bleeding. Biliary hemorrhage can occur when repeated inflammatory erosion causes the bile duct to connect with adjacent blood vessels. Clinical manifestations include periodic gastrointestinal bleeding, abdominal pain, and fever.
(4) Hepatobiliary stenosis. Hepatobiliary stones often lead to repeated inflammatory damage and repair of the bile duct wall, eventually causing fibrotic stenosis of the bile duct.
(5) Cholestatic hepatic sclerosis and portal hypertension. Diffuse intrahepatic bile duct stones can gradually lead to cholestatic hepatic steatosis and further cause portal hypertension.
What lesions can be caused by intrahepatic bile duct stones?
Some patients with cholelithiasis have gallstones not only in their gallbladder or common bile duct, but also in some bile ducts within the liver. In other cases, there are no stones in the gallbladder or common bile duct, but there are gallstones in the intrahepatic bile ducts. The presence of gallstones in the intrahepatic bile ducts is known medically as intrahepatic cholestasis. Intrahepatic bile duct stone disease is not common in western countries such as the United Kingdom and the United States, but it is quite common in China and Southeast Asian countries. In some provinces along the coast of China, especially in rural areas, a significant proportion of gallstone patients suffer from intrahepatic choledocholithiasis.
Intrahepatic bile duct stones are usually brown or brownish-yellow in color, with a brittle and brittle texture that looks like clay, and the chemical composition of the stones is mainly calcium bilirubin. How gallstones can be found in the intrahepatic bile ducts is not yet fully understood medically. According to doctors’ observations, bacterial infections, biliary roundworms and bile duct obstruction are closely related to the development of intrahepatic bile duct stones.
Intrahepatic cholestasis is considered by doctors as a special type of gallstone disease. This is not only because gallstones are located in a special part of the bile duct, the diagnosis of intrahepatic bile duct stones is not as easy as gallbladder stones and common bile duct stones, and it is often difficult to completely remove stones during surgery, but also because intrahepatic bile duct stones can cause more serious lesions in the bile duct and liver. When the intrahepatic bile ducts are affected by gallstones, the mechanical stimulation of the gallstones often leads to bacterial infection, causing inflammation of the bile ducts, which is often recurrent and persistent. The walls of the hepatic bile ducts containing stones are often significantly thickened, the lumen is dilated, the walls are damaged, ulcers are formed, and bile duct narrowing or even occlusion occurs due to scarring. Intrahepatic bile duct stones can also cause lesions in the liver, such as necrosis of liver tissue, formation of abscesses, and eventually atrophy of part of the liver and loss of normal function. Therefore, effective treatment of hepatic bile duct stones should be carried out early so as to achieve better treatment results.
What are the clinical features of hepatobiliary stones?
Hepatobiliary stones refer to the production of stones in the intrahepatic bile duct system, therefore, they are also called intrahepatic bile duct stones. They are often present in combination with extrahepatic bile duct stones, but there are also simple intrahepatic bile duct stones, also known as true intrahepatic calculi. In recent years, the number of cases of intrahepatic bile duct stones has increased, and such stones account for 15.4% of the 474 cases of surgically confirmed gallstone disease reported in China. Most of them are accompanied by common bile duct stones. The classification of stones is mostly bilirubin stones.
The hepatic bile duct stones are mostly yellowish-green masses or “mud-like” stones, mostly bilirubin calcium. Therefore, some physicians believe that hepatobiliary stones are caused by bile duct obstruction caused by biliary roundworms and bacterial infections.
Hepatobiliary stones are mostly found in the left lobe of the hepatic duct. The bile ducts at the confluence of the upper and lower hepatobiliary ducts in the left outer lobe of the liver are slightly enlarged, and the stones are mostly found in this area. Clinical features are mostly manifested as follows.
(1) Patients are younger than those with gallbladder stones, and some patients are associated with congenital abnormalities of the intrahepatic bile ducts. Patients often have a history of abdominal pain, chills, fever, and recurrent jaundice since early childhood.
(2) There is impairment of liver function, while gallbladder function may be normal. A variety of liver function abnormalities may occur during recurrent episodes, and alkaline phosphatase may rise during intervals; prolonged disease may lead to atrophy of liver lobe segments and liver fibrosis.
(3) Abdominal pain, jaundice and fever are the main symptoms, but the typical severe colic rarely occurs.
(4) Complications are numerous and more serious. The more common ones are purulent intrahepatic cholangitis, liver abscess, and biliary hemorrhage.
(5) Cholangiography may show dilated intrahepatic bile ducts without dilated extrahepatic bile ducts, with small translucent areas in the hepatic ducts.
What are the clinical manifestations of intrahepatic bile duct stones?
The clinical manifestations of intrahepatic bile duct stones may vary depending on the location of the lesion. When stones descend into the extrahepatic bile duct causing biliary obstruction or acute inflammation, epigastric colic, chills, high fever, jaundice and other manifestations of purulent cholangitis may occur. If the stone is not dislodged into the extrahepatic bile duct, sometimes it may be complicated by infection, and septic symptoms such as chills and high fever may occur, and in severe cases, toxic shock. However, the patient may not have abdominal cramps and jaundice, so it is often misdiagnosed. Some intrahepatic bile duct stones block the intrahepatic bile duct for a long time, resulting in atrophy of the liver tissue in the blocked area. The unobstructed normal liver tissue compensates for the hyperplasia, the compensated part enlarges, the atrophic part shrinks, the liver is deformed, and the gallbladder is displaced.
What are the characteristics of bile duct stones on ultrasound sonogram?
Ultrasound images of intrahepatic and extrahepatic bile duct stones are characterized by strong echogenic posttracking shadowing of the stones and dilatation of the bile ducts above the site of stone obstruction. Extrahepatic bile duct stones can sometimes move, but due to the curvature and narrowing of the bile duct, the contrast conditions of bile are poor, and it is not easy to get an accurate cross-section of the ultrasound scan when the stones are small, especially when there is flatulence or filling of the contents in the stomach and intestines. Generally speaking, the accuracy of ultrasound diagnosis of extrahepatic bile duct stones is much lower than that of gallbladder stones, so endoscopic retrograde cholangiopancreatography is often required to further clarify the diagnosis.
What is the significance of B-mode ultrasonography in the diagnosis of hepatobiliary stones?
B-mode ultrasonography is the preferred diagnostic method for hepatobiliary stones, with a diagnostic accuracy of 96.4%. The advantages of ultrasonography are.
(i) It is non-damaging to the patient, inexpensive and can be repeated from all directions.
②The ability to determine the presence, size and number of stones.
③The ability to localize stones and identify the accompanying intrahepatic bile ducts by intrahepatic portal vein branches, such as the right anterior, right posterior, left internal, and left external branches (class II hepatobiliary ducts).
④ To determine the degree of dilatation of the intra- and extrahepatic bile ducts and to understand the presence of obstruction or stenosis.
⑤ to understand the presence of any comorbidities, such as cholestatic liver abscess, biliary hepatic sclerosis, etc.
⑥Intraoperative ultrasound examination can monitor whether intrahepatic bile duct stones are removed and can guide the direction of intraoperative stone extraction.
The shortcoming of ultrasound examination is that it cannot directly show the site and degree of stricture, nor can it show the whole picture of the biliary system and the image map of the variation of biliary anatomy.
What diseases should be distinguished from hepatobiliary stones?
The clinical presentation of hepatobiliary stones is inconsistent and depends mainly on the site and degree of obstruction and the presence of secondary biliary tract infection. The following diseases need to be distinguished clinically.
(1) Foci of intrahepatic calcification and fibrotic scarring after local necrosis of liver tissue
With the popularization and development of ultrasound technology in hospitals at all levels, many healthy people find strong echogenic clusters and sound shadows similar to stones in the liver during physical examination, and many people mistakenly believe that they have intrahepatic bile duct stones. In fact, calcified foci in the liver and fibrotic scar of local necrosis of liver tissue can present strong echogenic masses and acoustic shadows similar to stones, but generally do not cause dilatation of the hepatic bile ducts. In contrast, stones have dilation in the small bile ducts above the obstruction site, and the strong echogenic masses of stones have a characteristic distribution along the course of the left and right hepatic ducts.
(2) Viral hepatitis
The disease may show right upper abdominal distension and jaundice, so it is easily mistaken for cholelithiasis. However, blood tests can reveal significantly elevated glutathione transaminase, and ultrasound examination shows no dilatation of the bile ducts inside and outside the liver and no stone strong echogenicity in the bile ducts.
(3) Liver abscess
This disease has symptoms such as epigastric pain and fever similar to hepatic bile duct stones. However, the diagnosis can be clearly made by ultrasound examination.
What are the principles of surgical treatment of hepatic bile duct stones and strictures?
The principles of treatment for hepatic bile duct stones and strictures are to remove the stones, release the obstruction, remove the lesion, and clear the drainage.
The choice of surgical approach and the number of previous surgeries are influenced by the extent of stones in the intrahepatic bile ducts, the number of stones, the accompanying changes in the bile ducts and liver, the timing of surgery (e.g., in the acute or chronic phase), and the number of previous surgeries, etc. Therefore, surgery is often highly individualized for different patients and should be chosen according to the type of pathology found during surgery or a combination of several procedures. The main objective of surgery should be to achieve the following The main objectives of surgery should be to
(i) Extraction of as many stones as possible.
(ii) To remove the lesion.
(iii) Correction of bile duct lesions.
④establishing unobstructed bile drainage.
⑤ to create conditions for adjuvant therapy after surgery.
Can intrahepatic bile duct stones be completely cured?
The treatment of intrahepatic bile duct stones is a difficult problem in the treatment of gallstone disease. As the stones penetrate deep into the branches of the intrahepatic bile duct, it is often very difficult to completely remove the stones during surgery, and intrahepatic bile duct stones can cause bile duct obstruction and secondary bacterial infection, which often leads to bile duct inflammation, scarring and narrowing of the bile duct, destruction and atrophy of the liver tissue, and even formation of liver abscess. .
In recent decades, doctors have made a lot of exploratory research on the treatment of intrahepatic bile duct stones, and designed many new surgical methods for the special lesions of the bile duct and liver caused by intrahepatic bile duct stones, which have significantly improved the treatment effect of bile duct stones in patients, mainly for the purpose of removing stones, unobstructing the bile duct and removing lesions.
(1) Removal of stones. The patient’s common bile duct can be incised and the stones in the common hepatic duct, common bile duct or larger branches of the intrahepatic bile duct can be removed through the incision in the common bile duct with stone extraction forceps or gallstone keys. In case of difficulty, the common bile duct incision can be extended upward to the upper end of the common hepatic duct, so that the stones can be removed more easily. Sometimes the liver tissue can be incised first, and then the intrahepatic bile duct can be incised to remove the stones.
(2) Unblock the bile duct. Surgery for intrahepatic bile duct stones often does not allow complete removal of the stones, and the surgeon often connects the bile duct directly to the small intestine during surgery and makes the interface as large as possible. In this way, gallstones that are not removed during surgery can later descend with the bile and enter the intestine through the interface between the bile duct and the small intestine, and then be excreted from the body. For bile duct strictures caused by intrahepatic bile duct stones, they should be incised during surgery to correct the stricture obstruction and unblock the bile duct.
(3) Removal of lesions. Bile duct obstruction by intrahepatic bile duct stones is often combined with infection and cholangitis, liver abscess, and liver tissue destruction and atrophy, which often become chronic lesions over time. If the lesion is limited to a part of the liver, this part of the liver tissue can be removed during surgery, and more satisfactory results are often achieved.
The surgical treatment of intrahepatic bile duct stones is often complex, and the surgeon should have a thorough understanding of the distribution of the stones and the nature of the lesions in the biliary tract and liver of each patient, and use different surgical methods according to the specific situation of each patient. After the surgery, some anti-inflammatory and biliary drugs should be taken, and roundworm treatment should be carried out to prevent the occurrence of biliary ascariasis. Nowadays, most of the patients can achieve better treatment effect through the above treatment, and some of them can also be cured.
What is transglottic intrahepatic biliary ductotomy for lithotripsy?
Transhepatic hilar choledochotomy is the basic surgical procedure for the surgical treatment of intrahepatic bile duct stones. The procedure is to expose the extrahepatic bile ducts through conventional biliary surgery, firstly to open the common bile duct, remove the stones and explore the lower end of the common bile duct, and then to extend the incision on the anterior wall of the common bile duct upwards to the upper end of the common bile duct, through which the left and right hepatic ducts and the openings on both sides of the caudal lobe hepatic duct can be exposed under direct vision. The patency of the ducts and the presence of pigmented sediment should be noted. The orientation of the openings of the second level of the intrahepatic bile ducts should be clarified as much as possible, and the stones should be removed from them. Generally, stones in the first-stage hepatobiliary duct or stones obstructing the openings of the second-stage hepatobiliary duct can be removed surgically, but stones in higher locations are often difficult to remove completely. After the stone is removed, depending on the presence or absence of bile duct stenosis, the appropriate surgical procedure is chosen, such as T-tube drainage, stenosis bile duct reconstruction, defective bile duct repair or bile duct jejunostomy Roux-en-Y anastomosis.
Why do intrahepatic bile duct stones sometimes need to be resected as liver lobes (segments)?
Intrahepatic bile duct stones, due to prolonged hepatobiliary obstruction and infection, can cause necrosis, fibrosis, atrophy of the hepatobiliary tissues in the diseased part or complicate abscess and biliary hemorrhage, etc. Therefore, hepatectomy is sometimes an important treatment for intrahepatic bile duct stones, which can not only remove stones but also remove infected lesions and reduce the chance of stone recurrence. However, hepatectomy does not completely prevent stone recurrence, so the indications for hepatectomy should be strictly controlled. It is generally accepted that local hepatectomy is often considered when intrahepatic bile duct stones exist in the following conditions.
(1) Lesions limited to one section, one lobe or one side of the liver, with significant fibrosis and atrophy of the liver tissue due to long-term obstruction and infection of the intrahepatic bile ducts, resulting in loss of liver tissue function and causing severe clinical symptoms.
(2) Intrahepatic bile duct stenosis complicated by hepatic bile duct stones on one side, and it is difficult to remove gallstones and correct the stenosis by other methods.
(3) Chronic liver abscess or multiple liver abscesses above the obstruction site in combination with stone obstruction.
(4) One side of the hepatobiliary stone combined with severe bile duct stenosis, infection, biliary fistula and other complications.
(5) One side of the hepatobiliary stone is complicated by hemorrhage in the intrahepatic bile duct, and the bleeding cannot be stopped by other methods.
What are the common surgical procedures for hepatic bile duct stones?
(1) The surgical procedures used to remove stones and lesions include
(1) Transhepatic hilar intrahepatic bile duct incision and exploration for stone extraction.
(ii) Transhepatic parenchymal intrahepatic bile duct dissection for stone extraction.
(iii) lobectomy or segmental resection of the liver.
(2) Commonly used procedures to cut stenosis, relieve obstruction and repair bile duct defects.
(i) stenosis bile duct incision and plasticization with a tipped jejunal flap to repair the bile duct defect.
(ii) stenosing bile duct incision and plasticization with gallbladder flap to repair hepatobiliary defects.
(3) Stenosing bile duct incision and plasticization with hepatic round ligament umbilical vein endoprosthesis to repair hepatobiliary duct defect.
(3) Procedure to enable bile duct drainage (bile-intestinal internal drainage).
(i) Bile duct jejunum Lu’s Y anastomosis.
(ii) interposed jejunal bile duct duodenal anastomosis.
(iii) interposed jejunal bile duct jejunostomy.
What factors can affect the efficacy of lithotripsy treatment for hepatic bile duct stones?
(1) Stenosis of the lower end of the common bile duct. Inflammatory fibrosis and stricture are mostly caused by long-term recurrent infection and stone irritation. A significant proportion of these patients can have their stones removed after concomitant duodenal papillary sphincterotomy.
(2) Stones are embedded in the bile duct wall. This often occurs at the lower end of the common bile duct. This type of stone is difficult to peel with the finger even during surgery, so it is difficult to treat the stone with simple stone removal.
(3) Stones that are too large or too many. Stones larger than 1 cm are difficult to expel. If the stones are small, but are large and fused together, it is also difficult to achieve results.
(4) Sediment-like stones. Sediment-like stones can fill the entire bile duct lumen and adhere to the bile duct wall, making them difficult to flow, so the treatment is not satisfactory.
(5) Inflammation in the bile duct is obvious. At this time, the bile is purulent, viscous and poorly mobile, so the effect of flushing and stone removal is weakened.
(6) The organic combination of lithotripsy, lithotripsy and lithotripsy can greatly improve the therapeutic effect. The effect of using only one method is poor.
(7) The mastery of treatment time. Clinical observation suggests that lithotripsy treatment within the scope of indications and during the onset of symptoms can play a causal role and facilitate stone discharge. Some people found that the stone removal rate is 20% to 40% higher when treated during the attack period than during the resting period after comparison.