Measurement of the endoscopic retrograde cholangiogram

Normal morphometry of the biliary tree in pediatric and adult populations: A systematic review and meta-analysis

PURPOSE

This study aimed to characterise the normal morphometry of the biliary tree in pediatric and adult populations, through a systematic review and meta-analysis.

METHODS

This study, conducted using the PRISMA guidelines and registered with PROSPERO, searched MEDLINE, EMBASE, SCOPUS and Web of Science databases up to October 2022, and updated to August 2023. Studies that reported extractable data on diameter and length of the right, left and common hepatic ducts (LHD, RHD and CHD), and common bile duct (CBD) were included. Quality of the included studies were assessed using the Anatomical Quality Assessment (AQUA) tool. Statistical analysis included subgroup analyses according to sex, age, geographical location, and imaging modality.

RESULTS

In total, 60 studies were included, of which 44 studies reported adequate data for meta-analysis on 23,796 subjects. Overall, the pooled mean diameter of the CBD was 4.69 mm (95 % CI: 4.28-5.11). Significant differences were found between pediatric (1.32 mm, 95 % CI: 1.03-1.61) and adult (4.97 mm, 95 % CI: 4.67-5.27) subjects, as well as US (3.82 mm, 95 % CI: 3.15-4.49) and other imaging modalities, including MRI (6.21 mm, 95 % CI: 4.85-7.57) and ERCP (7.24 mm, 95 % CI: 6.08-8.40). The CBD diameter measured significantly larger distally (5.20 mm, 95 % CI: 4.60-5.80) than proximally (4.01 mm, 95 % CI: 3.51-4.51).

CONCLUSIONS

The results obtained from this evidence-based study may guide the establishment of standardised reference values and ranges of the normal biliary tree in pediatric and adult populations and aid clinical understanding.

Pancreatographic investigation of pancreatic duct system and pancreaticobiliary malformation

To clarify the anatomy of the pancreatic duct system and to investigate its embryology, we reviewed 256 pancreatograms with normal pancreatic head, 81 with pancreas divisum and 74 with pancreaticobiliary maljunction. Accessory pancreatograms were divided into two patterns. The long-type accessory pancreatic duct forms a straight line and joins the main pancreatic duct at the neck portion of the pancreas. The short-type accessory pancreatic duct joins the main pancreatic duct near its first inferior branch. The short-type accessory pancreatic duct is less likely to have a long inferior branch arising from the accessory pancreatic duct. The length of the accessory pancreatic duct from the orifice to the first long inferior branch was similar in the short- and long-type accessory pancreatic ducts. The first long inferior branch from the long-type accessory pancreatic duct passes though the main pancreatic duct near the origin of the inferior branch from the main pancreatic duct. Immunohistochemically, in the short-type accessory pancreatic duct, the main pancreatic duct between the junction with the short-type accessory pancreatic duct and the neck portion was located in the ventral pancreas. The long-type accessory pancreatic duct represents a continuation of the main duct of the dorsal pancreatic bud. The short-type accessory pancreatic duct is probably formed by the proximal main duct of the dorsal pancreatic bud and its long inferior branch.

Pancreatico-choledochal junction and pancreatic duct system morphology in acute biliary pancreatitis. A prospective study with early ERCP

Sixty-two patients with acute biliary pancreatitis (ABP) were prospectively studied by early ERCP in order to evaluate the morphology of the pancreatico-choledochal junction and the pancreatic duct system (PDS) and compared with 62 control patients. Abnormalities of the ampulla of Vater were observed in 66.1% (33.5% in controls; p = 0.001). A common channel for the common bile duct and the main pancreatic duct (MPD) were found in 70.9% of ABP cases; the length of common channel was < or = 5 mm in 79.5% and > 5 mm in 20.4%; the angle between CBD and MPD was < or = 30 degrees in 88.6% and > 30 degrees in 11.4% (no difference compared to the control group). A patent Santorini's duct were found in 37% of ABP cases vs 38.7% in controls (NS); there was no significant difference in patency of the duct of Santorini between edematous and necrotizing cases of ABP. Morphological changes of the PDS were found in all patients with necrotizing (22 cases) and in 15 out of 40 patients with edematous ABP (p < 0.0001).

ERCP findings and the role of endoscopic sphincterotomy in acute gallstone pancreatitis

A total of 131 patients with acute pancreatitis (of whom 100 had gallstones) underwent endoscopic retrograde cholangiopancreatography (ERCP) during the same hospital admission. Urgent ERCP (less than 72 h) was performed in 68 cases and early ERCP (3-30 days) in 63 cases; 47 had predicted severe attacks and 84 had predicted mild attacks (modified Glasgow criteria). The highest incidence of common bile duct stones occurred in those with predicted severe attacks and those who had urgent ERCP. Highly significant correlations were found between age and common bile duct and pancreatic duct diameters. Significant correlations were also found between the common bile duct and pancreatic duct (correcting for age) and between these and the admission serum bilirubin. The common bile duct diameter was greatest in those with common bile duct stones and predicted severe attacks. A considerably lower incidence of pancreatic duct filling occurred in those with predicted severe attacks and common bile duct stones; in predicted mild attacks the pancreatic duct diameter was greater in those with common bile duct stones. In gallstone patients complications were highest in those with predicted severe attacks but more significantly in those with common bile duct stones. Endoscopic sphincterotomy was undertaken in 37 patients with common bile duct stones without mortality. The overall complication rate in gallstone patients was 19 per cent and the mortality rate was 2 per cent. These findings suggest that common bile duct stones cause acute common bile duct and pancreatic duct obstruction and are closely associated with complications. Urgent ERCP for detection of common bile duct stones, and endoscopic sphincterotomy for treatment, is strongly recommended for patients with predicted severe attacks due to gallstones and should also be considered for others who fail to show clinical improvement.

Endoscopic retrograde cholangiograms of the normal and post-cholecystectomy biliary tree

The diameter of extrahepatic and intrahepatic bile ducts was measured on 50 normal retrograde cholangiograms and on the cholangiograms of 109 post-cholecystectomy patients undergoing endoscopic retrograde cholangiopancreatography: 70 of the post-cholecystectomy patients had a normal cholangiogram and 39 had retained stone or biliary stricture, of whom 17 were jaundiced. Biliary diameter at all points measured was greater in the post-cholecystectomy patients with no biliary lesion than in normals, and further increased in the presence of pathology (e.g. retained stone). The extent of overlap in biliary diameter between all these three groups is so great that measurement of bile duct calibre cannot separate patients with retained stone from post-cholecystectomy patients without retained stone, or from patients with an entirely normal biliary tree, even in the presence of obstructive jaundice. Methods of evaluating the biliary tract which rely on the measurement of bile duct diameter (e.g. ultrasound) are therefore of limited value in the investigation of post-cholecystectomy patients.