Sphincter of Audi dysfunction

Introduction

Introduction to Audi sphincter dysfunction The sphincter of Oddidysfunction (SOD) is an abnormal contraction of SO, a benign, non-calculus obstruction in which bile or pancreatic juice is blocked through the junction of the pancreaticobiliary junction (ie, SO). basic knowledge The proportion of sickness: 0.004% - 0.005% Susceptible people: no specific people Mode of infection: non-infectious Complications: jaundice, diarrhea

Cause

Causes of abnormal sphincter function in Audi

(1) Causes of the disease

1. The incidence of SOD after cholecystectomy is 0.88%. In the United States, about 700,000 people undergo cholecystectomy every year. Among them, 6100 cases have SOD. There are many cases of cholecystectomy in China. It is estimated that SOD cases are also Not less, but there is still no systematic statistics.

2. Secondary to other diseases such as systemic sclerosis, diabetes or chronic pseudo-intestinal obstruction.

3. Unidentified causes are unknown.

4. Drugs that can increase sphincter tone include cholinergic agonists, alpha-agonists, H1 agonists, and opioids.

(two) pathogenesis

SOD includes SO dyskinesia or SO stenosis. SO dyskinesia is an abnormality of primary SO movement, which can cause sphincter dystrophy, but more commonly sphincter tension is too high. In contrast, SO stenosis indicates sphincter structure changes. Perhaps due to the inflammatory process, and there may be secondary fibrosis, because it is often difficult to distinguish between patients with SO dyskinesia and SO stenosis, so the term SOD is commonly used to refer to these two types of patients, in order to facilitate the treatment of the cause, but also to decide whether SO manometry (SOM) is required. Patients with suspected SOD are often classified according to clinical history, laboratory examination and ERCP results using the Hogan-Geenen SOD clinical classification system.

Other terms describing SOD in the medical literature, such as nipple stenosis, ampullary stenosis, biliary dyskinesia, and post-cholecystectomy syndrome, are less accurate and less accurate than SOD.

The sphincters around the ampulla and the end of the bile duct are collectively referred to as SO and consist of four parts: the common bile duct sphincter, the main pancreatic duct sphincter, the ampulla of the nipple, the longitudinal muscle bundle at the septum, and the SO pressure. The high area is 4 to 10 mm long. Its function is to regulate the discharge of bile and pancreatic juice, avoid duodenal fluid reflux, maintain the aseptic environment in the pancreatic duct, and SO has varying basic pressure and phase contraction movement. It seems to dominate, allowing bile and pancreatic juice to drain into the duodenum to aid digestion, although SO phase contraction can help regulate bile and pancreatic juice outflow, but their primary role seems to be to prevent duodenal contents from being reversed to the pancreaticobiliary Flow, SO is regulated by different nerves and body fluid signals. The systolic phase contraction wave activity is closely related to the duodenal transitional motor complex (MMC). It is reported that the function of the sphincter after liver transplantation is protected, so the biliary tract Innervation does not seem to be important for SO, although it partially transmits non-adrenergic energy of the vascular intestinal polypeptide (VIP), non-cholinergic neurons and nitric oxide can relax SO, but cholecystokinin ( The role of CCK) and secretin in causing sphincter relaxation seems to be the most important. The role of cholecystectomy in altering these neural pathways needs further confirmation. Luman et al reported that cholecystectomy inhibits pharmacological doses of CCK at least in the short term. The normal inhibition of SO, but the mechanism of action remains unclear.

SO wedge specimens obtained from SOD in SOD patients showed evidence of inflammation, muscle hypertrophy, fibrosis or endometriosis in the nipple region of approximately 60% of patients, suggesting SO in 40% of patients with normal histology Movement disorders, occasionally, cytomegalovirus, Cryptosporidium (such as AIDS patients) or the infection of the genus A. elegans, also cause SOD.

How does SOD cause pain? In theory, SO abnormalities can cause high blood pressure in the pancreas and bile duct by obstructing the discharge of bile and pancreatic juice; ischemia due to contraction of sputum; "allergies" of nipples, which can cause pain Although there is currently no evidence, these mechanisms may explain pain independently or together.

Prevention

Audi sphincter dysfunction prevention

For the prevention of a clear cause (such as: after the cholecystectomy, some drugs that can increase the sphincter tone).

Complication

Audi sphincter dysfunction Complications jaundice diarrhea

General pain episodes are not accompanied by jaundice, chills or fever, even if jaundice is mostly mild sclera yellow staining, jaundice can completely resolve after 1 to 2 days of pain relief, even if there is fever, most do not exceed 38 ° C, followed by nausea , vomiting, belching and diarrhea.

Symptom

Audi sphincter dysfunction symptoms common symptoms nausea abdominal tenderness chills persistent pain fever

Abdominal pain is the most common symptom. Abdominal pain is usually located in the upper abdomen or right upper abdomen. It can be severe and lasts for 30 minutes to several hours. Some patients have persistent paroxysmal aggravation, which can be radiated to the back or shoulders with nausea. , vomiting, food or anesthetics may aggravate the pain. Abdominal pain can begin several years after cholecystectomy due to gallbladder dyskinesia or calculi. The nature of abdominal pain is similar to the pain that causes the primary disease of cholecystectomy. The patient may still have Cholecystectomy can not alleviate persistent pain, jaundice, fever or chills are rare, the diagnostic criteria of Rome IISOD is severe pain in the paroxysmal upper abdomen and right upper abdomen, with the following manifestations: symptoms lasting 30min or longer There is a painless interval; there are 1 or more similar symptoms in the previous 12 months; abdominal pain is persistent and often affects daily activities or need to see a doctor; there is no evidence of structural abnormalities to explain these symptoms, physique The examination is characterized by the absence of any abnormal findings, the most common signs being mild, non-specific abdominal tenderness, for peptic ulcer or irritable bowel syndrome Experimental drug treatment can not alleviate the abdominal pain of SOD. In the case of typical abdominal pain, the abnormality of the laboratory examination does not exceed 50% of the patient, including short-term liver function elevation. After the initial evaluation, the patient is usually in accordance with Hogan-Geenen SOD. Classification systems are classified, and SOD patients can exhibit typical pancreatic abdominal pain [radial to the upper abdomen and/or left upper abdominal pain] and recurrent pancreatitis.

Examine

Examination of abnormal sphincter function in Audi

Some patients have recurrent or persistent serum bilirubin, bile acid, ALP, aminotransferase and amylase elevation, especially common in ALP, and biliary enzymes often increase with the onset of abdominal pain, with Abdominal pain relieved and returned to normal.

1. Morphine-Newsin excitation test (Nardi test)

Morphine has the effect of causing SO contraction. After subcutaneous injection of 10 mg of morphine, subcutaneous injection of neostigmine 1 mg as a stimulant for cholinergic secretion, morphine-neosmide excitation test is widely used, the traditional method of diagnosing SOD, if Typical abdominal pain occurred in patients with AST, ALT, AKP, amylase or lipase increased more than 4 times, positive for the test. This test predicts the specificity of SOD, has low sensitivity, and has a very good predictive effect after sphincter incision. Poor correlation, so the application is limited and replaced by more sensitive tests.

2. Ultrasound examination of extrahepatic bile duct and main pancreatic duct diameter after secretion stimulation

After high-fat meal or CCK application, gallbladder contraction, hepatocyte excretion of bile increases, and SO relaxes, causing bile to enter the duodenum. Similarly, after high-fat meal or application of secretin, stimulate pancreatic secretion, SO relaxation If the SO function is abnormal and causes obstruction, the common bile duct or the main pancreatic duct can be dilated under the pressure of the secretion fluid. Ultrasound examination can be used to monitor the sphincter and end biliary and pancreatic duct obstruction caused by other causes (calculus, tumor, stenosis, etc.). It can also cause dilatation of the common bile duct or main pancreatic duct. Except for the need, it should also be noted whether there is exacerbation of abdominal pain. So far, research in this area is limited. These non-invasive tests are compared with the effects of SOM or sphincter incision. Only showed a slight correlation, because of the intestinal gas, conventional percutaneous ultrasound, can not see the pancreatic duct, although endoscopic ultrasound can see the superiority of the pancreas, but Catalano et al reported in the diagnosis of SOD, The sensitivity of endoscopic ultrasonography after secretin stimulation was only 57%.

3. Quantitative hepatobiliary scintigraphy (HBS)

A scintigraphic scan of the liver and gallbladder estimates that bile discharge, sphincter disease, tumor or stone (and liver parenchymal disease) causes bile outflow to be blocked, causing abnormal discharge of radionuclides, and clear criteria for defining positive (ie, abnormal) results remain controversial. However, the most widely used is the arrival time of the duodenum is greater than 20min and the time from the hilar to the duodenum is greater than 10min. The defect of most studies is the lack of correlation with the results of SOM or sphincter incision, however, A study clearly indicated that hepatobiliary scintigraphy was significantly associated with SO-based pressure. In summary, patients with bile duct dilatation and apparent obstruction may have positive scintidal results. Esber et al found that patients with hepatobiliary scintigraphy were not severely obstructed even after CCK challenge. (Hogan-Geenen classifications II and III), scintillation scans are usually normal.

Recently, there have been reports of morphine challenge in hepatobiliary scintigraphy. 43 patients with clinically diagnosed type II and III have experienced hepatobiliary scintigraphy with and without morphine, and later biliary fluid pressure measurement. Standard hepatobiliary scan cannot distinguish Patients with normal and abnormal SOM, however, after morphine challenge, the maximum activity time and the percentage of excretion at 45 min and 60 min were significantly different, using a 15% excretion of excretion at 60 min, and a hepatobiliary scintigraphy scan by morphine challenge amplification The sensitivity and specificity of elevated SO base pressure were 83% and 81%, respectively.

The lack of more positive data now leads to the conclusion that non-invasive methods of SOD have relatively low or unclear sensitivity and specificity and are therefore not recommended for clinical use unless a positive test method is used (eg Pressure) is unsuccessful or cannot be checked.

Because of the associated risk, invasive ERCP and manometry should be used only for clinical symptoms. In general, if sphincter dysfunction is found, it is not recommended for patients with SOD unless the treatment is intended to be affirmative (sphincter incision). Invasive assessment.

Cholangiography

Cholangiography is important for stones, tumors, or other biliary obstructive diseases that have the same symptoms as SOD. Once high-quality cholangiography is excluded, expansion and/or slow bile ducts often indicate obstruction. Sphincter level, cholangiography can be obtained by a variety of methods, venography has been replaced by more accurate methods, spiral CT cholangiography or magnetic resonance cholangiography seems promising, can be used percutaneous method The Chinese method or the more traditional ERCP obtained direct cholangiography. Although there is some controversy, if the extrahepatic bile duct diameter exceeds 12 mm (after cholecystectomy) after correction and amplification, it should be considered as dilatation, affecting bile discharge and SO sphincter relaxation or The contracted drug can affect the discharge of the contrast agent. In order to obtain accurate discharge time, it is necessary to avoid the application of such drugs. Because the common bile duct has an angle from front to back, in order to exclude the gravity of the drainage fluid through the sphincter, the patient must be supine. Position, although there is no good definition of the normal discharge time of the contrast agent in the supine position, but after cholecystectomy In 45 minutes, the biliary tract cannot empty all the contrast agents, and it is usually abnormal.

Endoscopy around the nipple and nipple can provide important information for the diagnosis and treatment of patients with SOD. Occasionally, papillary cancer can also be misdiagnosed as SOD. For suspicious individuals, nipple biopsy should be performed.

X-ray features of the pancreatic duct are also important in assessing patients with suspected SOD. Pancreatic duct dilatation (>6 mm in the pancreatic head and >5 mm in the pancreatic body) and prolonged discharge of the contrast agent (prone position 9 min) provide SOD presence. Indirect evidence.

5.SO pressure measurement

SOM is the only method that can directly measure SO motor activity. Although SOM can be performed intraoperatively and percutaneously, it is most often measured at ERCP. Most authorities believe that SOM is the gold standard for assessing SOD and detect Oddi sphincter movement. Disordered fluid pressure measurement is similar to its application in other parts of the gastrointestinal tract. Unlike other areas of the intestine, SOM is technically more demanding and more dangerous. The question remains whether such short-term observations (2 to 10 min) Each pull can reflect the "pathophysiology of the sphincter" for 24 hours. Despite this or some problems, SOM is still being widely used in clinical applications.

SOM is usually performed at ERCP. All relaxation (anticholinergic, nitrate, calcium channel blockers and glucagon) or irritation (anaesthetic) should be avoided during 8-12 h before pressure measurement and during the whole manometry. Or cholinergic drugs) sphincter drugs, the current data suggest that benzodiazepines do not affect sphincter pressure, so SOM can be used for sedation, the recent data suggest that the dose of piperidin is less than 1m / kg, does not affect the sphincter basis Stress (although it does affect the characteristics of the phase wave), because the basal pressure of the sphincter is usually the only stress standard used to diagnose SOD and determine treatment, it is generally recommended that petrolidine can be used to assist in analgesia when measuring pressure. If glucagon must be applied in order to complete the intubation, at least 8-10 minutes is required to restore the sphincter to its basal state.

Multiple types of three-lumen catheters can be used for pressure measurement. Tubes with long tube heads help the catheter to be fixed in the bile duct, but often prevent pancreatic duct pressure measurement. SOM requires selective bile ducts and/or cannula tubes to pass through. Gently aspirate to identify the inserted catheter, see the yellow liquid in the endoscopic field of view to enter the bile duct; extract the clear liquid prompts to enter the pancreatic duct, preferably before the SOM bile duct and pancreatic duct angiography, because of positive findings (eg, common bile duct stones) may avoid SOM, and Blaut et al. have recently shown that injecting contrast into the biliary tract prior to SOM does not significantly alter sphincter pressure.

In order to ensure the correct pressure measurement, it must be confirmed that the pressure measuring catheter is not blocked by the tube wall. Once the catheter is inserted into the lumen, it is removed by a fixed-point pulling method, each time 1-2 mm, and each point is pressed for 30-60 s until the catheter is completely withdrawn. SO, ideally, the pancreatic duct and bile duct pressure are measured, because one sphincter (such as the pancreatic sphincter) may be abnormal and the other sphincter is normal. Raddawi et al reported that the abnormal basal pressure of the pancreatitis patient is more likely to be confined to the patient's pancreatic duct. Sphincter; in patients with biliary pain, limited to the biliary sphincter, and abnormal liver function tests, usually normal SO base pressure 35mmHg, contraction amplitude 220mmHg, contraction interval 8s, contraction frequency 10 times / min, retrograde contraction 50%, the abnormal pressure measurement of SOD is manifested as an increase in the base pressure, the contraction amplitude or contraction frequency exceeds normal, and the retrograde contraction exceeds 50%, wherein the increase in basic pressure is the most constant and reliable indicator, which is often used in treatment programs. Determination is also a good indicator to judge the prognosis of SO cut.

The main complication after SOM is pancreatitis, especially in patients with chronic pancreatitis. Rolny et al reported that the incidence of pancreatitis after pancreatic duct manometry is 11%; after SOM in patients with chronic pancreatitis, 26% have pancreatitis. The following methods may reduce the incidence of pancreatitis after pressure measurement:

(1) The use of a suction catheter can continuously drain the liquid that is poured into the lumen.

(2) Drain the pancreatic duct after pressure measurement.

(3) Reduce the lumen perfusion rate to 0.05 ~ 0.1ml / min.

(4) Limit the pancreatic duct pressure measurement time to less than 2 min (or avoid pancreatic duct pressure measurement).

(5) Using a micro-transducer system, in a prospective randomized study, Sherman et al found that the frequency of aspiration catheters to reduce pancreatitis-induced pancreatitis decreased from 31% to 4%.

SOM is recommended in patients with idiopathic pancreatitis or unexplained severe biliary pancreatic pain. According to the Hogan-Geenen SOD classification system, SOM indications are also evolving.

6. As a stent test for diagnostic tests

Although the purpose of the pancreatic or biliary stent test is to reduce pain and predict whether a more positive treatment (ie, sphincter incision) is effective, this has only limited application, especially in patients with normal pancreatic ducts, if the pancreatic duct stent Being retained for more than a few days, severe pancreatic duct and parenchymal injury may occur. Goff reported 21 patients with normal biliary tract type II and III SOD who underwent biliary stenting. If the symptoms were alleviated, the 7F stent was retained for at least 2 months; If it is judged to be ineffective, the stent is removed immediately, and the pain relief after stent placement predicts that the pain can be relieved long after the biliary sphincter incision. Unfortunately, 38% of patients have pancreatitis after placement of the stent (14% is severe) because High complication rates, biliary stenting were strongly prevented, and Rolny et al also reported biliary stent placement in 23 patients after cholecystectomy (7 patients with type II and 16 patients with type III) as predictive endoscopic sphincterotomy The effect, similar to Goff's study, regardless of the pressure of the SO, during at least 12 weeks of stent placement, the pain disappeared predictive of sphincter incision, but did not occur with the stent Place the relevant complications.

Diagnosis

Diagnostic diagnosis of sphincter dysfunction in Audi

Diagnostic criteria

Patients with a history of biliary and gallbladder surgery may also develop SOD because the symptoms of SOD or abnormal gallbladder function are not easily distinguishable, so SOD diagnosis is usually made after cholecystectomy, or SOD is occasionally diagnosed after proper examination has excluded gallbladder abnormalities.

Clinical evaluation

The presence of major clinical features can influence the diagnosis of suspected SOD. However, the clinical manifestations of abnormal SO function are not always easy with organic diseases (such as common bile duct stones) or other functional non-biliary or pancreatic diseases. (such as irritable bowel syndrome) is distinguished.

2. General initial inspection

Assessment of patients with suspected SOD (ie, patients with upper abdominal pain indicative of pancreatic or biliary disease characteristics) should first be examined from liver function, amylase and/or lipase, abdominal ultrasound and/or CT, as may If the serum enzyme test should be carried out during the onset of abdominal pain, SOD is often mildly elevated (less than 2 times the upper limit of normal), and significantly elevated often indicates stones, tumors and liver parenchymal diseases, although abnormal liver function tests for the diagnosis of SOD Sensitivity and specificity are quite low, but recent evidence suggests that in patients with biliary type II SOD, abnormal liver function findings predict the effect of endoscopic sphincterotomy, CT scans and abdominal ultrasound are often normal, but sometimes found Bile duct or pancreatic duct dilatation (especially patients with type I SOD), routine examination and treatment of other common upper gastrointestinal diseases (such as peptic ulcer and gastroesophageal reflux) should be performed simultaneously, in the absence of mass lesions, stones, Sphincter disease should be highly suspected when there is no response to acid suppression test.

Because SOM (the gold standard for diagnosing SOD) is difficult and invasive, it is not widely used, and SOM has a relatively high incidence of complications. To diagnose patients with SOD, some non-invasive and stimulating tests have been designed. .

Differential diagnosis

1. The lower part of the common bile duct should be differentiated from the papillary sphincter and the organic lesion involving the common bile duct. It can be performed by retrograde cholangiopancreatography (ERCP) and percutaneous transhepatic cholangiography (PTC). Identification.

2. Gallbladder (tube) stones can lead to gallbladder dilation, need to be differentiated from hypertonic gallbladder and hypokinetic gallbladder, imaging diagnosis (B-ultrasound, CT and MRI) can be found in gallbladder (tube) stones to confirm the diagnosis.

3. The inflammation and infection around the ampulla of the ampulla can be similar to the increase of Oddi sphincter tension, but it can be confirmed by endoscopy.

4. Peri-ampullary and pancreatic head tumors can be distinguished by imaging examination, endoscopy, PTC and surgical exploration and Oddi sphincter tension.

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