The exocrine part of the pancreas has a duct system called the pancreatic ductal system (PDS). Its mechanism of development is complex, and any reorganization during early embryogenesis can give rise to anatomical variants. The aim of this study is to collect, classify, and analyze published evidence on the importance of anatomical variants of the PDS, addressing gaps in our understanding of such variations. The MEDLINE, Web of Science, Embase, and Google Scholar databases were searched to identify publications relevant to this review. R studio with meta-package was used for data extraction, risk of bias estimation, and statistical analysis. A total of 64 studies out of 1,778 proved suitable for this review and metanalysis. The meta-analysis computed the prevalence of normal variants of the PDS (92% of 10,514 subjects). Type 3 variants and "descending" subtypes of the main pancreatic duct (MPD) predominated in the pooled samples. The mean lengths of the MPD and accessory pancreatic duct (APD) were 16.53 cm and 3.36 cm, respectively. The mean diameters of the MPD at the head and the APD were 3.43 mm and 1.69 mm, respectively. The APD was present in only 41% of samples, and the long type predominated. The pancreatic ductal anatomy is highly variable, and the incorrect identification of variants may be challenging for surgeons during ductal anastomosis with gut, failure to which may often cause ductal obstruction or pseudocysts formation.

Pancreatic duct stenting using endoscopy or surgery is widely used for the management of benign and malignant pancreatic diseases. Endoscopic pancreatic stents are mainly used to relieve pain caused by chronic pancreatitis and pancreas divisum, and to treat pancreatic duct disruption and stenotic pancreaticointestinal anastomosis after surgery. They are also used to prevent postendoscopic retrograde cholangiopancreatography pancreatitis and postoperative pancreatic fistula, treat pancreatic cancer, and locate radiolucent stones. Recent advances in endoscopic techniques, such as endoscopic ultrasonography and balloon enteroscopy, and newly designed stents have broadened the indications for pancreatic duct stenting. In this review we outlined the types, insertion procedures, efficacy, and complications of endoscopic pancreatic duct stent placement, and summarized the applications of pancreatic duct stents in surgery.

The spectrum of pathologies affecting the biliary tree in the pediatric population varies depending on the age of presentation. While in utero insults can result in an array of anatomic variants and congenital anomalies in newborns, diverse acquired biliary pathologies are observed in older children. These acquired pathologies display different presentations and consequences than adults. Multimodality imaging assessment of the pediatric biliary system is requisite to establishing an appropriate management plan. Awareness of the imaging features of the various biliary pathologies and conveying clinically actionable information is essential to facilitate appropriate patient management. In this paper, we will illustrate the anatomy and embryology of the pediatric biliary system. Then, we will provide an overview of the imaging modalities used to assess the biliary system. Finally, we will review the unique features of the pediatric biliary pathologies, complemented by histopathologic correlation and discussions of clinical management.

Central pancreatectomy (CP) has been used sparingly because the spectrum of indications is quite narrow. The author has modified the procedure of CP in such a way to avoid distal pancreatic segment drainage, in addition to reserving the patient euo-insulinemic.

Between March 2010 and January 2015, 41 cases have been recruited. Cases presented with blunt abdominal trauma showing central pancreatic transection with or without duodenal transection have been recruited. Technique of CP has been modified to enable sparing distal pancreatic drainage procedure. The study describes a case series where the modified technique in the field of pancreatic surgery is applied on trauma patients through both laparoscopic and open approaches according to patients' hemodynamic stability.

There was no pancreatic fistula, deficiency nor any of the major complications related to the traditional CP technique.

None of the cases developed pancreatic necrosis or fistula, steatorrhea or showed picture of diabetes mellitus. The new technique has used the available anatomic and functional pancreatic facts to revolute sparing the distal pancreatic drainage procedure.

Pancreatic changes in aging have been described for many decades. They involve not only pancreatic parenchyma but also pancreatic ductal, microscopic, and exocrine functional changes. There have been many studies of these changes based on pathology and various imaging modalities, as well as functional studies. The pancreatic volume was found to decrease with advancing age, with a higher incidence of pancreatic steatosis, as demonstrated in autopsy and imaging studies. The pancreatic ductal structure has been described with wide ranges of normal variation, but many studies have shown a tendency toward enlargement with advancing age. By endoscopic ultrasound imaging, the aging pancreas may exhibit abnormal findings similar to chronic pancreatitis. Microscopically, there has been evidence of patchy lobular fibrosis and papillary hyperplasia and demonstrable k-ras mutation in both normal and dysplastic ductal mucosa. The evidence of pancreatic exocrine insufficiency has yielded conflicting results, but most studies have shown a tendency toward decreased pancreatic exocrine function in the elderly. Differentiating pancreatic change in the elderly from early chronic pancreatitis may be difficult as there are limited studies to compare these two conditions in terms of structural and functional changes.

Abnormal pancreatic function tests have been reported to precede the imaging findings of chronic pancreatitis. Magnetic resonance imaging (MRI) with magnetic resonance cholangiopancreatography (MRCP) is increasingly accepted as the primary imaging modality for the detection of structural changes of early mild chronic pancreatitis. The aim of this study was to evaluate MRI/MRCP findings in patients with symptoms consistent with chronic pancreatitis who have normal Secretin Endoscopic Pancreatic Function test.

A retrospective study of 32 patients referred for evaluation of chronic abdominal pain consistent with chronic pancreatitis and reported normal standard abdominal imaging (ultrasound, computed tomography, or MRI). All patients underwent Secretin Endoscopic Pancreatic Function testing and pancreatic MRI/MRCP at our institution. We reviewed the MRI/MRCP images in patients who had normal Secretin Endoscopic Pancreatic Function testing. MRI/MRCP images were assessed for pancreatic duct morphology, gland size, parenchymal signal and morphology, and arterial contrast enhancement.

Of the 32 patients, 23 had normal Secretin Endoscopic Pancreatic Function testing, and 8 of them had mild to marked spectrum of abnormal MRI/MRCP findings that were predominantly focal. Frequencies of the findings were as follows: pancreatic duct stricture (n=3), pancreatic duct dilatation (n=3), side branch ectasia (n=4), atrophy (n=5), decreased arterial enhancement (n=5), decreased parenchymal signal (n=1), and cavity formation (n=1). The remaining15 patients had normal pancreatic structure on MRI/MRCP.

Normal pancreatic function testing cannot exclude abnormal MRI/MRCP especially focal findings of chronic pancreatitis. Further studies needed to verify significance of these findings and establish MRI/MRCP imaging criteria for the diagnosis of chronic pancreatitis.

A wide spectrum of anomalies of the pancreas, the pancreatic ductal system, and the biliary tree are commonly encountered at radiologic evaluation. These anomalies may simulate various neoplastic, inflammatory, and posttraumatic conditions and should be part of the differential diagnosis for a variety of abnormalities found at diagnostic imaging. Anatomic variants, developmental anomalies (eg, pancreas divisum, annular pancreas, ectopic pancreas, pancreatic agenesis and hypoplasia), and congenital diseases (congenital pancreatic cysts, von Hippel-Lindau disease, choledochal cysts), in addition to potential imaging pitfalls (uneven distribution of fat, "pseudomasses"), can all pose a diagnostic challenge for the radiologist. Familiarity with these anomalies, the imaging techniques available for their study, and their variable imaging manifestations is necessary for differentiating them from other biliary and pancreatic conditions. A basic understanding of the embryologic development and normal anatomy of the pancreas and biliary tree is also essential for identifying these anomalies.

Stents have been used to relieve pancreatic duct stricture and upstream dilatation. However, many of these stents are straight-type stents originally manufactured for biliary use. A plastic stent that was developed for use in the pancreatic duct was used in this study and its usefulness investigated.

The stent (s-type stent: 10 Fr in diameter) has two alternate flexions and the shape resembles the tilde mark " approximately " in appearance. After obtaining informed consent, stents were placed in 20 patients with abdominal pain caused by chronic pancreatitis and stricture of the distal main pancreatic duct. The stents were removed according to the clinical manifestations and replaced with new ones if the stricture persisted.

In total, 33 stents were placed in 20 patients. Pain relief was attained in 19 patients (95%). The stricture improved after one stenting in 8 patients (40%). Owing to persistent stricture, the stenting was repeated in 11 patients. The 50% stent indwelling period was 369.0 days. No proximal or distal migration of the stent occurred and there were no serious complications.

In view of its long durability as a stent and no migration, the s-stent is safe and useful for the management of pancreatic ductal strictures in patients with chronic pancreatitis.

This study evaluated the normal pancreaticobiliary ducts of Koreans and assessed the frequency and pattern of variations and anomalies of these structures.

A prospective, nationwide multicenter study was performed in which 10 university hospitals in Korea participated from March 1997 to June 1999. A total 10,243 patients undergoing ERCP were enrolled.

The mean (SD) maximal and midportion diameters in millimeters of the common hepatic duct were, respectively, 6.1 (1.8) and 5.3 (1.6). The mean maximal and midportion diameters (mm) of the common bile duct were, respectively, 6.4 (1.8) and 5.5 (1.7). The mean maximal and midportion diameters (mm) of the main pancreatic duct in the head, body and tail were, respectively, 3.2 (1.1), 2.7 (1.0), and 2.5 (2.3); and, respectively, 2.2 (0.9), 1.6 (0.7) and 1.4 (0.6). Pancreaticobiliary duct diameters for patients above the age of 40 were greater than those of patients less than 40 years of age (p < 0.05). The frequency of choledochal cyst and anomalous union of the pancreaticobiliary ducts were, respectively, 0.32% and 4.1%. Pancreas divisum and annular pancreas were found, respectively, in 0.49% and 0.05%.

A knowledge of normal pancreaticobiliary ductal structures as well as the frequency and pattern of variations including anomalies is essential for the diagnosis and treatment of pancreaticobiliary disorders.

The aetiological role of biliary lithiasis for chronic pancreatitis remains controversial. Previous studies based on pancreatographic studies reported changes in the pancreatic duct system caused by biliary lithiasis. This study analysed retrospectively the endoscopic retrograde cholangiopancreatography of 165 patients presenting with biliary lithiasis and of 53 controls. Among the 165 patients, 113 had choledochal stones (53 with gall bladder stones, 50 had had a cholecystectomy, 10 with a normal gall bladder), 35 had gall bladder stones without choledochal stones, 17 had cholecystectomy for gall bladder stones. Pancreatograms were analysed by measuring the diameter of the pancreatic duct in the head, the body, and the tail of the pancreas, and evaluating the regularity of the main pancreatic duct and the presence of stenosis, the regularity or the dilatation of secondary ducts, and the presence of cysts. In addition, we established a score, based on the above parameters, by which pancreatograms were classified as normal or with mild, intermediate, moderate or severe abnormalities. A multivariate analysis (stepwise multiple discriminant analysis) was performed for age, sex, presence of gall stones, presence of choledochal stones. Patients were comparable with controls for sex, alcohol consumption but were younger (55 v 68 years, p < 0.01). In patients and in controls, the frequency of pancreatographic abnormalities increased significantly with age. The pancreatographic features of patients and controls were not significantly different. In the multivariate analysis, age was the only factor with significant predicting value for pancreatographic abnormalities. In conclusion, biliary lithiasis in itself is not an aetiological factor for chronic pancreatitis, older age being responsible for the abnormalities seen by pancreatography of patients with biliary lithiasis.

Knowledge of the surgical embryology and surgical anatomy of the pancreas is vital to the general surgeon. This article discusses the entities related to pancreatic surgery. It also highlights some common embryologic anomalies of the pancreas.

Gallstones are well known to cause acute pancreatitis. However, the role of gallstone disease in the causation of chronic pancreatitis is still controversial. Abnormalities of the pancreatic duct have been noted in about one-half of patients with calculous biliary disease undergoing endoscopic retrograde cholangiopancreatography (ERCP), but despite this, it is generally believed that gallstones rarely, if ever, cause chronic pancreatitis. The clinical significance and the natural history of the pancreatographic changes seen in patients with gallstone disease is not known. Studies of the pancreatic functions and long-term follow-up of patients with calculous biliary disease, especially those who have abnormal pancreatograms, and the effect of removal of the gallstone on the pancreatographic abnormalities and pancreatic functions are needed to clarify the issue.

Studies in the West have shown that with advancing age there is progressive atrophy and fibrosis of the pancreas. In addition, there is a gradual increase in diameter of the main pancreatic duct (MPD) with age. However, there is a discrepancy between the findings at autopsy and findings at endoscopic retrograde pancreatography (ERP). To examine this issue, ERP of subjects who were found not to show any abnormality of the biliary and pancreatic ducts were selected. They were divided by decade from 10 to 70 years and for statistical analysis into young (less than 40) and older (greater than or equal to 40) patients. There was no difference in length of the MPD between the two groups. However, the width of the MPD in the head was significantly greater in the older subjects (group 2; mean +/- SD = 3.78 +/- 0.97 mm) compared with those who were less than 40 years (group 1; 2.97 +/- 0.71 mm; p less than 0.001). Similarly, in the midbody the width of the MPD in group 2 (2.86 +/- 0.9 mm) was significantly greater compared with group 1 (2.36 +/- 0.51 mm; p less than 0.02). However, there was no difference in width of the MPD in the tail between the two groups. Length of the accessory pancreatic duct (APD) did not show any alteration with age but width was significantly greater in group 2 (1.94 +/- 0.69) compared with group 1 (1.49 +/- 0.51; p less than 0.05). No difference was observed in the length and width of the MPD or APD between male and female subjects of either group.(ABSTRACT TRUNCATED AT 250 WORDS)

The establishment of endoscopic retrograde cholangiopancreatography (ERCP) as a valuable procedure in diagnostic evaluation of patients with suspected pancreatic disease requires the precise delineation of normal pancreatography. Therefore, to establish normal standards in Koreans of pancreatic ductal morphology, such as course, diameter and length including the shape of the ampulla and the success rate of the ERCP procedure, we analyzed the pancreatograms of persons with proven normal pancreatic status. Of the 449 cases showing normal duodenal papilla, the hemispherical type of shape (49.7%) was the most common, followed by the papillary type (36.5%) and flat type (13.8%) in order of frequency. The success rate of ERCP procedure (1,020 cases) was 95.3%, and the selective success rate was 90.9% for the pancreatic duct and 79.3% for the biliary tree. In the course of the pancreatic duct (286 cases), the ascending type of extension (51.7%) was the most common followed by the sigmoid type (25.2%), horizontal type (22.4%) and descending type (0.7%). The diameter of the pancreatic duct was 3.3 +/- 0.8 mm in the head, 2.4 +/- 0.5 mm in the body and 1.5 +/- 0.5 mm in the tail portion, and there was a tendency that the diameter of the pancreatic duct progressively increased with age. The length of the pancreatic duct was 17.5 +/- 2.8 cm. In conclusion we hope that, by utilizing these various parameters of the normal endoscopic retrograde pancreatogram, precise diagnosis will be possible.

Fifty-seven patients with suspected pancreaticobiliary pathology constituting a clinical subset in whom the diagnosis was problematic or nonspecific were evaluated with computed tomography and ERCP. The relative sensitivities, specificities, and accuracies of the two tests were compared. Computed tomography was successful in obtaining a diagnostic examination in 100% and ERCP was technically successful in 75%. Both tests were equally accurate in detecting an abnormality (computed tomography 95.7%; ERCP 95.3%) and offering a correct diagnosis (computed tomography 72%; ERCP 70%). Sensitivity and specificity of the two tests for detection of an abnormality was computed tomography 100% and 91.3%; ERCP 91.7% and 100%. Sensitivity and specificity for the correct diagnosis was computed tomography 59% and 91.3%; ERCP 46% and 100%. Computed tomography was also superior to ERCP in making a correct diagnosis in pancreatic carcinoma (80% versus 63%) and pancreatitis (75% versus 50%). Based on these results we conclude that computed tomography utilizing high doses of intravenous contrast material and thin collimation is the preferred screening examination for pancreaticobiliary disease. ERCP should be reserved for those cases where the pancreaticobiliary disease. ERCP should be reserved for those cases where the diagnosis on computed tomography is obscure or uncertain and/or the pancreatic or biliary ductal anatomy requires direct contrast imaging.

The relationship between pancreas divisum and pancreatic disease has been studied in a series of 304 patients. This congenital anatomic variant, consisting of a separate pancreatic ductal system, was diagnosed by endoscopic pancreatography and dorsal duct opacification was achieved in 97 of these patients. This anatomic variation was observed with the same frequency in cases of pancreatitis (acute and chronic) (6.9%) and in the series of patients investigated by endoscopic pancreatography taken as a whole (5.7%). Moreover, incidences of pancreatic disease in patients with and without pancreas divisum were not statistically different when compared. These results show that pancreas divisum should not be regarded as an etiologic factor in pancreatitis but should be considered as a coincidental anatomic variant encountered in nearly 10% of the population. The results obtained herein do not support the hypothesis that stenosis of the accessory papilla occurs frequently in cases of pancreas divisum. We conclude that no further therapy should be systematically proposed for patients with pancreas divisum and pancreatitis.

Six patients with the congenital anomaly, pancreas divisum, and recurrent acute pancreatitis were treated surgically. The diagnostic triad of multiple episodes of abdominal pain with elevated serum amylase and identification of the anomaly by ERCP was present uniformly. Sphincteroplasty of the ampulla of Vater and ductoplasty of the accessory papilla were performed in five patients. One patient had sphincteroplasty only due to failure to identify the accessory duct. Two patients eventually required major pancreatic resection for pain relief. Three additional patients were identified and managed nonoperatively. Data of 44 patients with surgically treated pancreas divisum have been collected from the literature. Review of these patients indicates that dual sphincteroplasty or dorsal ductoplasty are the two most frequently employed procedures and appear to give good results.

The embryologic defect that results when the ventral and dorsal anlages of the pancreas do not fuse has been referred to as pancreas divisum. ERCP has made it possible to recognize this anomaly in patients undergoing investigation for otherwise unexplained abdominal pain. Of 70 patients in whom recurrent epigastric pain and pancreas divisum coexisted, sphincteroplasty of both papillae was carried out in 19 because of intractability of symptoms. In six patients, surgery was performed subsequent to failure of other biliary tract surgery. There was one postoperative death. In the remaining 18 patients, initial results were good to excellent in 13 and fair in 1. In four patients, however, recurrence of symptoms developed within periods that ranged from 1 to 6 months; therefore, reasonably permanent relief was limited to 10 patients. Of the remaining eight patients with recurrent or continuing symptoms, a variety of subsequent procedures led to satisfactory results in only three. In only seven patients was there even minimal chemical or microscopic evidence to suggest active pancreatitis. Similarly, pancreatograms in 17 patients with this anomaly revealed no abnormalities except for minor ones in 2 patients. Thus, if this is a syndrome that is due to relative stenosis of the lesser papilla and duct, the anomaly does not often result in documented pancreatitis. The definite but limited success rate from sphincteroplasty suggests that relative stenosis of the lesser papilla may be the cause of a syndrome but surgical refinements will be necessary to achieve a better operative success rate.

A postmortem radiographic investigation of 330 pancreas specimens showed a total frequency of 10 per cent for the 3 variants of the pancreatic duct system, in which the main pancreatic duct drained to the minor duodenal papilla (type III). In no instance did the main duct drain into the duodenum distal to the major papilla, onto which the common bile duct drained as usual. In the most common variant, type III-B, a separate accessory duct drained part of the pancreatic head onto the major papilla. In the remaining cases either an analogous accessory duct existed, communicating with the main duct (type III-A) or no accessory duct at all (type III-C). The different features of the accessory and main duct systems of type III in the pancreatic head varied widely. In types III-A and III-B, the corresponding ventral and dorsal pancreatic primordia formed more or less of mainly the posterior and anterior parts of the pancreatic head, respectively.

In a prospective ultrasonic study of the pancreatic duct, 233 sonograms were obtained from 49 normal subjects. The duct in the regions of the head-neck and body was measured in the transverse/oblique planes. The mean diameter of the duct in the area of the head-neck was 3 mm; in the body proximal and distal to the neck, duct diameters were 2.1 and 1.6 mm, respectively.

Computed tomography (CT) and ultrasound (US) were performed on 47 patients with a normal pancreas. CT was a significantly better method than US to demonstrate the pancreatic body and tail. The pancreatic head was also shown more often using CT than US, but this difference was not statistically significant. The diameters of the different parts of the pancreas measured at CT were significantly larger than measured at US. The explanation is most probably that the widths of the splenic and superior mesenteric veins are added to the diameters of the pancreas measured at CT, while using US, these vessels are clearly differentiated from the pancreatic tissue. US was a significantly better technique than CT to register the vascular structures surrounding the pancreas, except from the left renal vein, which was more often demonstrated at CT.

The main pancreatic duct has been visualized with both ultrasound and computed tomography. A normal pancreatic duct has not been reported using CT, and controversy persists over whether a normal duct can be routinely imaged with ultrasound. The dilated pancreatic duct has always been associated with disease -- usually pancreatitis or a proximal obstructing pancreatic carcinoma. In the patient with no clinical history or laboratory data suggesting pancreatitis, a dilated pancreatic duct implies a proximal tumor.

In this paper, recent advances in the diagnosis of pancreatic disease are reviewed, together with older methods currently in use. The clinical role of these techniques in the diagnosis of pancreatic disease is discussed with particular reference to symptomatology and prognosis of the various pancreatic disorders. Likely future developments in this field are considered.

Pancreas divisum occurs when the embryological ventral and dorsal parts of the pancreas fail to fuse, so that pancreatic drainage is mainly through the accessory papilla. In 169 patients with primary biliary tract disease who underwent pancreatography incidental to endoscopic cholangiography, the incidence of pancreas divisum was 3.6%. Among 78 patients with unexplained recurrent pancreatitis, the incidence was 25.6%. The hypothesis that the duct anomaly can cause obstructive pain and pancreatitis is presented, and supported by a detailed analysis of 47 patients with the condition.

A successful pancreatogram was obtained at endoscopic retrograde cholangiopancreatography (ERCP) in 53 patients with calculous biliary disease. Twenty-eight patients presented with jaundice and 25 with pain. In both groups there was a high incidence of pancreatogram abnormalities (47 and 48 per cent respectively). These findings demonstrate that the pancreas is often abnormal in the presence of complicated calculous biliary disease even though there may be no recent clinical evidence of pancreatitis and suggest that asymptomatic chronic pancreatitis may be common. The clinical significance of the abnormalities is discussed.

Endoscopic retograde cholangiopancreatography (ERCP) is currently utilized to evaluate jaundice, both intra- and extrahepatic, and can differentiate between these by demonstrating specific anatomic lesions. ERCP is definitive in the evaluation of gallbladder disease when other modalities are indefinite. For the first time outside the operating room, the pancreatic duct can be opacified by ERCP. The newest application of ERCP, endoscopic papillotomy (EP), has revolutionized the treatment of common bile duct gallstones and stenosis of the duct, offering a safe and effective alternative to repeated surgery, especially in those patients at risk. Because of these diverse and effective applications, ERCP has become firmly established in our diagnostic armamentarium.

Retrospective evaluation of the results of endoscopic retrograde cholangiopancreatography (ERCP) and pancreatic ultrasonography in identifying those patients with a normal pancreas and those with a pancreatic abnormality revealed ultrasonography to have an overall accuracy of approximately 73%, whereas ERCP had an 85% accuracy, and both modalities had a combined accuracy of 92%. Both procedures were most accurate in the identification of patients with no disease, and both were least accurate in the identification of patients with chronic pancreatitis.