gallstone impaction at the ampulla of vater can cause cholangitis as well as pancreatitis , and urgent stone removal is critical for improving the patient s condition 1 
 2 
 3 
 4 
 5 
 6 . the standard treatment is endoscopic papillotomy , but in recent years , some patients have been reluctant to undergo this procedure because of having bleeding tendencies as a result of oral antithrombotic agents , disseminated intravascular coagulation ( dic ) , hemodialysis , or liver cirrhosis . some of these factors are reported to increase the risk of post - papillotomy bleeding 7 
 8 
 9 . for patients at risk of hemorrhage , we performed biliary drainage without papillotomy , despite the stone impaction , followed by a second procedure for stone extraction . the purpose of this study was to clarify the clinical features of gallstone impaction at the ampulla of vater and to examine the effectiveness of endoscopic biliary drainage without papillotomy . we retrospectively examined the records of 30 patients who had undergone endoscopic treatment for gallstone impaction at the ampulla of vater at our hospital between 2010 and 2015 . only patients with gallstones were included , with pancreatic stones excluded ; and it was an inclusion criterion that the impacted stone at the ampulla of vater were endoscopically confirmed ( fig .  1 and fig .  2 ) . although the ampulla of vater is prominent , the stone can not be visually confirmed . gallstone impaction can be diagnosed by papillotomy.the patients in both fig .  1 and fig . 2 were diagnosed as gallstone impaction , defined as endoscopically confirmed impacted stone at the ampulla of vater . duodenoscopes with a backward viewing angle of 15 ( jf-260v , olympus medical systems corp , tokyo , japan ) were used in this study . the catheters used were pr-104q , pr-128q , and pr - v614  m ( olympus ) . the guidewires used were a 0.035-inch straight jagwire ( boston scientific japan , tokyo , japan ) and a 0.025-inch angle visiglide ( olympus ) . the practitioner and assistant were experts who had treated >  500 patients with endoscopic retrograde cholangiopancreatography ( ercp ) . after biliary cannulation ( 2 patients required pre - cutting ) , endoscopic sphincterotomy ( est ) was performed with a small - to - medium incision , and a 7-fr endoscopic nasobiliary drainage ( enbd ) tube was installed . the 17 patients in group b had undergone biliary drainage without papillotomy . all of them had some type of hemorrhage risk . selective biliary cannulation without pre - cutting was achieved in all patients in group b. the impacted stone was pushed back into the bile duct using a catheter , and then a 5- or 7-fr enbd catheter was put in place ( video 1 ) . deep biliary cannulation was performed to push the stone using the catheter and remove the impaction . because the patient had multiple hemorrhage risks ( oral administration of antithrombotic and hemodialysis ) , a 7-fr endoscopic nasobiliary drainage tube was installed without papillotomy . repeat ercp for stone removal was performed in 2 of 13 patients in group a and in all patients in group b. the second treatment was performed several days after cholangitis had eased in group a and after treatment to control the risk of bleeding in group b. the parameters examined for each patient included 1 ) clinical features ; 2 ) ct findings ; and 3 ) endoscopic treatment . statistical analyses were performed using the student s t test and chi - square test to compare the two groups , and probability ( p ) values of <  0.05 were considered to indicate a statistically significant difference . the clinical features of the patients ( 21 male and 9 female ) are shown in table  1 . the mean    standard deviation ( sd ) age was 76.1    12.1 years .   according to the severity classification for acute cholangitis in the tokyo guidelines ( tg13 ) . according to the definition in american collage of gastroenterology ( acg ) score of   4 points according to the scoring system of the japanese association for acute medicine . hyperbilirubinemia ( total bilirubin [ t - bil ] >  2.0  mg / dl ) was observed in 23 patients ( 77  % ) , and hyperamylasemia ( serum amylase [ amy ] >  125 according to the severity classification for acute cholangitis in the tokyo guidelines ( tg13 ) 10 , the condition was mild in 8 patients , moderate in 14 patients , and severe in 8 patients . twelve patients met the case definition of acute pancreatitis according to the american collage of gastroenterology ( acg ) guidelines 11 ( established by the presence of 2 of the 3 following criteria ; ( i ) abdominal pain consistent with the disease ; ( ii ) serum amylase and/or lipase greater than three times the upper limit of normal ; and ( iii ) characteristic findings from abdominal imaging . according to the revised atlanta classification , 11 patients had mild pancreatitis and 1 had moderate pancreatitis 12 . complications included dic ( with a score of   4 points according to the scoring system of the japanese association for acute medicine 13 ) in 4 patients and hypotension requiring catecholamines in 4 patients . one patient had renal failure requiring hemodialysis , 1 had liver cirrhosis because of hepatitis c ( child  pugh class c , 10 points ) , and 1 had idiopathic thrombocytopenia ( itp ) . five patients ( 17  % ) had poor common bile duct dilatation ( <  10  mm ) . the stone at the ampulla could be identified in the majority of the patients ( 24/30 ; 80  % ) , but there were 6 patients in whom it could not be identified ( fig .  3 and fig .  4 ) . five patients had clear pancreatitis ( defined as an elevated concentration of fatty tissue surrounding the pancreas ) , including 4 patients with inflammation up to the anterior pararenal extraperitoneal space , and 1 patient with inflammation beyond the inferior pole of the kidney . defined as elevated concentration of fatty tissue surrounding the pancreas ; 4 patients with inflammation up to the anterior pararenal extraperitoneal space , and 1 patient with inflammation beyond the inferior pole of the kidney . this was an example of a patient for whom identification of the stone was difficult by ct . biliary cannulation was achieved without pre - cutting in 28 patients ( 93  % ) , with normal cannulation in 23 of these patients and wire - guided cannulation in the other 5 . in 2 patients , deep cannulation was achieved after pre - cutting ( needle knife fistulotomy ) , and est was subsequently performed . the patients in group a , who underwent biliary drainage with papillotomy , were compared with those in group b , who underwent biliary drainage without papillotomy . no differences were observed between the 2 groups with respect to the other clinical factors ( table  3 ) . all patients in group b had some type of hemorrhage risk : oral administration of antithrombotic agents in 12 patients , disseminated intravascular coagulation in 4 patients , hemodialysis in 1 patient , liver cirrhosis in 1 patient , and itp in 1 patient . not significant for each grade of cholangitis . there were no differences between the 2 groups in the success rate of the biliary drainage , the rate of elevated amylase ( amy ) the following day , or procedure - related complications ( table  4 ) . the serum amy levels decreased the following day in all patients , even in group b ( including the 10 patients with hyperamylasemia and the 3 patients with clear pancreatitis on ct ) . serum amy level was used as an objective indicator for impaired outflow of pancreatic juice because ct was not repeated , and it was difficult to assess the clinical symptoms precisely . although there was no statistically significant difference , the duration of treatment was longer in group a than in group b. in group a , 11/13 patients underwent complete stone extraction as part of the same procedure . the remaining 2 patients had several stones , and repeat ercp was performed to remove the stones several days after the inflammation had eased ( 4 days later for 1 patient and 6 days later for the other ) . all the patients in group b underwent repeat treatment for stone removal , which was performed at a mean of 6.3 days later ( range , 3    14 days ) . action was taken to suppress the bleeding tendency as much as possible ; antithrombotic agents were stopped temporarily in 6 patients , heparin was replaced in 4 , there was recovery of dic in 4 , and 1 patient underwent platelet transfusion . ampulla treatment included endoscopic papillary balloon dilatation ( epbd ) in 11 patients and est in 6 patients . the clinical features of the patients ( 21 male and 9 female ) are shown in table  1 . the mean    standard deviation ( sd ) age was 76.1    12.1 years .   according to the severity classification for acute cholangitis in the tokyo guidelines ( tg13 ) . according to the definition in american collage of gastroenterology ( acg ) score of   4 points according to the scoring system of the japanese association for acute medicine . hyperbilirubinemia ( total bilirubin [ t - bil ] >  2.0  mg / dl ) was observed in 23 patients ( 77  % ) , and hyperamylasemia ( serum amylase [ amy ] >  125 according to the severity classification for acute cholangitis in the tokyo guidelines ( tg13 ) 10 , the condition was mild in 8 patients , moderate in 14 patients , and severe in 8 patients . twelve patients met the case definition of acute pancreatitis according to the american collage of gastroenterology ( acg ) guidelines 11 ( established by the presence of 2 of the 3 following criteria ; ( i ) abdominal pain consistent with the disease ; ( ii ) serum amylase and/or lipase greater than three times the upper limit of normal ; and ( iii ) characteristic findings from abdominal imaging . according to the revised atlanta classification , 11 patients had mild pancreatitis and 1 had moderate pancreatitis 12 . complications included dic ( with a score of   4 points according to the scoring system of the japanese association for acute medicine 13 ) in 4 patients and hypotension requiring catecholamines in 4 patients . one patient had renal failure requiring hemodialysis , 1 had liver cirrhosis because of hepatitis c ( child  pugh class c , 10 points ) , and 1 had idiopathic thrombocytopenia ( itp ) . five patients ( 17  % ) had poor common bile duct dilatation ( <  10  mm ) . the stone at the ampulla could be identified in the majority of the patients ( 24/30 ; 80  % ) , but there were 6 patients in whom it could not be identified ( fig .  3 and fig .  4 ) . five patients had clear pancreatitis ( defined as an elevated concentration of fatty tissue surrounding the pancreas ) , including 4 patients with inflammation up to the anterior pararenal extraperitoneal space , and 1 patient with inflammation beyond the inferior pole of the kidney . defined as elevated concentration of fatty tissue surrounding the pancreas ; 4 patients with inflammation up to the anterior pararenal extraperitoneal space , and 1 patient with inflammation beyond the inferior pole of the kidney . this was an example of a patient for whom identification of the stone was difficult by ct . biliary cannulation was achieved without pre - cutting in 28 patients ( 93  % ) , with normal cannulation in 23 of these patients and wire - guided cannulation in the other 5 . in 2 patients , deep cannulation was achieved after pre - cutting ( needle knife fistulotomy ) , and est was subsequently performed . the patients in group a , who underwent biliary drainage with papillotomy , were compared with those in group b , who underwent biliary drainage without papillotomy . no differences were observed between the 2 groups with respect to the other clinical factors ( table  3 ) . all patients in group b had some type of hemorrhage risk : oral administration of antithrombotic agents in 12 patients , disseminated intravascular coagulation in 4 patients , hemodialysis in 1 patient , liver cirrhosis in 1 patient , and itp in 1 patient . not significant for each grade of cholangitis . there were no differences between the 2 groups in the success rate of the biliary drainage , the rate of elevated amylase ( amy ) the following day , or procedure - related complications ( table  4 ) . the serum amy levels decreased the following day in all patients , even in group b ( including the 10 patients with hyperamylasemia and the 3 patients with clear pancreatitis on ct ) . serum amy level was used as an objective indicator for impaired outflow of pancreatic juice because ct was not repeated , and it was difficult to assess the clinical symptoms precisely . although there was no statistically significant difference , the duration of treatment was longer in group a than in group b. in group a , 11/13 patients underwent complete stone extraction as part of the same procedure . the remaining 2 patients had several stones , and repeat ercp was performed to remove the stones several days after the inflammation had eased ( 4 days later for 1 patient and 6 days later for the other ) . all the patients in group b underwent repeat treatment for stone removal , which was performed at a mean of 6.3 days later ( range , 3    14 days ) . action was taken to suppress the bleeding tendency as much as possible ; antithrombotic agents were stopped temporarily in 6 patients , heparin was replaced in 4 , there was recovery of dic in 4 , and 1 patient underwent platelet transfusion . ampulla treatment included endoscopic papillary balloon dilatation ( epbd ) in 11 patients and est in 6 patients . according to the tg13 classification for the severity of acute cholangitis 10 , cholangitis was severe in only 8 ( 27  % ) of the 30 patients , despite the gallstone impaction at the ampulla of vater . the tg13 guidelines also specify the drainage urgency according to the degree of severity ( fig .  5 ) 14 . urgent drainage is recommended for severe cholangitis , whereas for mild - to - moderate conditions , conservative treatment can be given priority . however , there is a risk of delaying drainage in impaction cases with mild - to - moderate cholangitis ; regardless of the severity of the cholangitis , impaction cases need urgent drainage . the pathology of cholangitis involves inflammation of the bile duct ( often associated with bacterial infection ) , and there is a physical obstruction of bile juice flow with stone impaction at the ampulla of vater . therefore , even in patients with impaction , some cases present mild - to - moderate cholangitis . the recommended treatment course according to the severity of acute cholangitis in the tokyo guidelines ( tg13 ) . hyperamylasemia was observed in 18 patients ( 60  % ) , and 5 patients ( 17  % ) exhibited clear pancreatitis as evidenced by imaging . the definition for acute pancreatitis according to the acg guidelines was satisfied by 12 patients ( 40  % ) . hyperamylasemia was suggestive of the impaired outflow of pancreatic juice ; nevertheless , pancreatitis was not obvious in all the patients on imaging studies .   this may be attributed to the involvement of factors such as the patency of the accessory pancreatic duct , and the degree of impaction . 15 reported that patency of the accessory pancreatic duct with acute pancreatitis was significantly lower than in control cases . they build up a hypothesis that a patent accessory pancreatic duct may function as a second drainage system for the main pancreatic duct , reducing the pressure in the main pancreatic duct and preventing acute pancreatitis . furthermore , it may be inferred that the risk of pancreatitis onset differs depending on the degree of impaction . in other words , it is possible that there is a high risk of pancreatitis when severe impaction causing prominent papillary edema and pancreatic duct obstruction is present , whereas the risk of pancreatitis is low when there is mild impaction that only causes biliary obstruction . in summary , typical clinical features of cholangitis and pancreatitis were rarely associated with gallstone impaction in the current study . kwang et al . examined 46 patients with gallstone impaction at the ampulla of vater and observed charcot s triad , the 3 typical findings of cholangitis , in 22  % of the patients , and pancreatitis ( defined as abdominal pain plus serum amy  >  3    upper limit of the normal level ) was observed in 37  % 2 . hence , they reported that typical cholangitis and pancreatitis are rare in patients with impaction , which is similar to our findings .   with impacted stone , cannulation is considered difficult . however , misra et al . were able to perform normal cannulation in 23/32 ( 72  % ) patients with impacted stone , reporting that 9 patients required pre - cutting with a needle knife 16 . in our study , we were able to achieve deep cannulation without pre - cutting in 28/30 ( 93  % ) patients . we believe that standard biliary cannulation is possible in most patients , even those with impaction . papillotomy is standard treatment for gallstone impaction 1 
 2 
 3 
 4 
 5 
 6 . however , post - papillotomy bleeding , which sometimes occurs , can be a problem . 7 reported that users of anticoagulants are at high risk of bleeding both with est and with epbd . hemodialysis and liver cirrhosis are also reported to increase risks for post - est bleeding 8 
 9 . in recent years , many patients have been reluctant to undergo papillotomy because of having a bleeding tendency . for patients at risk of hemorrhage , we perform biliary drainage without papillotomy even for impacted stone , followed by a second procedure for stone extraction . when performing drainage , the impacted stone is pushed back into the bile duct with the catheter . in the current study , serum amy levels decreased the following day in all patients , even those in group b. drainage without papillotomy is acceptable with impacted stone accompanying hyperamylasemia and pancreatitis . in our opinion , the removal of the impacted stone  rather than the papillotomy  is of greatest importance . if the impaction is removed and biliary drainage performed , the patient s condition will improve . in patients at risk of hemorrhage , papillotomy is not required . first , in a minority of patients , cannulation is not possible without pre - cutting . in this study , 2 patients required pre - cutting for severe impaction and papillary edema . in such patients , at a higher risk of bleeding , pre - cutting had to be given priority . the second limitation is that the hospital stay tended to be longer when only drainage was initially performed because the second procedure for stone extraction was required . an additional limitation is that this retrospective study was conducted at a single facility and included only a small sample population . in conclusion , the typical clinical features of cholangitis and pancreatitis were rarely associated with gallstone impaction at the ampulla of vater . the condition of patients will improve with biliary drainage without papillotomy , even those who have hyperamylasemia and pancreatitis . initial papillotomy is therefore not essential . a treatment strategy that considers the risk of hemorrhage
background and study aims : gallstone impaction at the ampulla of vater is a critical condition , and the standard treatment is endoscopic papillotomy . 
 however , the clinical features remain largely unclear , and some patients are reluctant to undergo papillotomy because of a bleeding tendency . the aim of this study was to clarify the clinical features of gallstone impaction at the ampulla of vater and to examine the effectiveness of endoscopic biliary drainage without papillotomy . 
 patients and methods : we retrospectively examined 30 patients who had undergone endoscopic treatment for gallstone impaction at the ampulla of vater between 2010 and 2015 . 
 results : according to the severity classification for acute cholangitis in the tokyo guidelines ( tg13 ) , the condition was mild in 8 patients , moderate in 14 , and severe in only 8 ( 27  % ) , despite the stone impaction at the ampulla of vater . 
 hyperamylasemia was observed in 18 patients ( 60  % ) ; computed tomography ( ct ) revealed clear pancreatitis in 5 cases ( 17  % ) . 
 patients were classified into group a ( 13 patients who received biliary drainage with papillotomy ) and group b ( 17 patients receiving biliary drainage without papillotomy ) . 
 all patients in group b had 1 or more types of hemorrhage risk . 
 there were no differences between the 2 groups in the success rate of biliary drainage , the rate of elevated serum amylase the following day , or procedure - related complications . 
 serum amylase levels decreased the following day in all patients , even in group b ( including the 10 patients with hyperamylasemia and the 3 patients with clear pancreatitis on ct ) . 
 conclusions : even with stone impaction at the ampulla of vater , typical clinical features of cholangitis and pancreatitis are relatively rare 
 . biliary drainage without papillotomy is acceptable for gallstone impaction at the ampulla of vater .