the term  groove pancreatitis  was first used in 1973 by becker to describe a specific form of chronic pancreatitis that resulted in scarring , which extended into the anatomic space (  groove  ) between the pancreatic head , duodenum , and common bile duct .
more recently , preoperative diagnosis of groove pancreatitis has been emphasized to avoid unnecessary radical surgery .
groove pancreatitis is not common , and only one case was recorded , but not published , in korea .
a 46-year old man was admitted to our hospital with severe postprandial abdominal pain in the right upper quadrant .
he complained of right upper abdominal pain that lasted for six months and weight loss of 12 kg over the same period . during the last few weeks
iu / l ) , total bilirubin 0.5 mg / dl ( normal range 0.21.2 ) , alkaline phosphatase 69
iu / l ) , and alt 20 iu / l ( normal range 544 iu / l ) .
tumor markers were also within normal range : carcinoembryonic antigen 1.46 ng / ml ( normal range < 5.0
iu / l ) and carbohydrate antigen 19 - 9 3.17 u / ml ( normal range < 39 iu / l ) . abdominal ultrasonography showed a non - homogeneous mass measuring 32 mm in diameter between the pancreatic head , descending duodenum , and common bile duct , as well as swelling of the pancreatic head ( figure 1 ) .
endoscopy revealed duodenal wall thickening adjacent to the major papilla , with narrowing of the duodenal lumen .
computed tomography ( ct ) revealed swelling of the pancreatic head and a non - homogeneously enhanced , low - density area between the pancreatic head , descending duodenum , and common bile duct ( figure 2a ) .
the head of the pancreas was enhanced on contrast ct scan and peripancreatic vessel encasement was not seen ( figure 2b ) .
mr images revealed a mass between the pancreatic head , duodenum , and common bile duct that was hypointense on t1-weighted images ( figure 3a ) and hypointense relative to the pancreatic head on t2-weighted images ( figure 3b ) . on t1-weighted images
, we observed the medial wall thickening of the descending duodenum , several small cysts in the groove and thickened duodenal wall on enhanced images ( figure 3c , 3d ) .
the patient has been under conservative treatment for 2 months and his severe abdominal pain has improved .
although he continues to have mild postprandial discomfort , he refuses evaluation and treatment for his disease .
groove pancreatitis is a rare form of chronic pancreatitis affecting the groove between the pancreatic head , the duodenum , and common bile duct .
there are two forms of groove pancreatitis : one is pure groove pancreatitis that only affects the groove , the other is segmental groove pancreatitis that affects the groove and the parenchyma of pancreas . commonly reported symptoms include severe upper abdominal pain , recurrent postprandial vomiting , jaundice , diarrhea , and weight loss .
although the pathogenesis of groove pancreatitis remains unclear , it is suspected to be associated with previous history of disease in the biliary system , peptic ulcers , gastric resections , true duodenal wall cysts , pancreatic head cysts , pancreatic heterotopia in the duodenum , disturbed pancreatic juice flow in the santorini duct in the absence of the minor papilla , and hypersecretion ancillary to alcohol abuse . in one study , 17 cases of groove pancreatitis were reviewed .
the 17 patients had a median age of 51 years , and 16 of the 17 patients were alcoholics .
symptoms of abdominal pain were observed in 6 , vomiting in 4 and jaundice in 2 of the patients .
the pure form differentiates duodenal cancer , cbd cancer , and acute pancreatitis with phlegmon . for the segmental form ,
while pancreatic cancer mass is seen as non - enhanced , in this disease , dynamic ct generally reveals an enhanced mass in the groove or the pancreatic head .
other findings suggestive of groove pancreatitis include cysts in the duodenal wall and/or the groove , and duodenal stenosis accompanied by wall thickening .
poor enhancement of scar lesions in groove pancreatitis may be due to delayed circulation caused by proliferation of fibrous tissues with attendant arterial constriction .
the most characteristic finding on mri is a sheet - like mass between the head of the pancreas and the duodenum , associated with duodenal wall thickening .
the mass is hypointense compared to pancreatic parenchyma on t1-weighted images , and iso- to slightly hyperintense on t2-weighted images .
dynamic imaging typically shows delayed enhancement . in our patient , the symptoms were postprandial right upper quadrant abdominal pain , watery diarrhea , and weight loss .
abdominal ct revealed a non - homogeneously enhanced mass lesion at the groove and pancreatic head .
abdominal ct revealed a mass with duodenal wall thickening , but endoscopic biopsy specimens obtained from the mucosa of the second portion of the duodenum only showed inflammation .
abdominal mri revealed a sheet - like mass at the groove , associated with duodenal wall thickening and cysts .
, we were able to diagnose segmental groove pancreatitis preoperatively . although groove pancreatitis is not rare , only a few cases have been reported due to a lack of awareness .
all clinicians should be familiar with its clinical features and keep them in mind for the differential diagnosis of pancreatic masses and duodenal stenosis .
 groove pancreatitis is a special form of chronic pancreatitis in which scarring is found mainly in the groove between the pancreatic head , duodenum , and common bile duct . 
 preoperative differentiation between groove pancreatitis and pancreatic cancer is difficult . 
 here we report one case of segmental groove pancreatitis diagnosed by clinical and radiological features . 
 the patient was a 46-year old man with severe abdominal pain , weight loss , and a long history of alcohol abuse . 
 computed tomography revealed swelling of the pancreatic head and a heterogeneously enhanced low - density lesion in the groove . 
 mr images revealed a mass in the groove that had a low signal on t1-weighted images and a low signal relative to the pancreatic head on t2-weighted images . 
 t1-weighted images on dynamic study showed the medial wall thickening of descending duodenum , several small cysts in the groove and thickened duodenal wall . 
 the patient has been under conservative treatment for 2 months and his severe abdominal pain has improved . 
INTRODUCTION
CASE REPORT
DISCUSSION