Type:
Educational Exhibit
Keywords:
Abdomen, Pancreas, MR, Comparative studies, Decision analysis, Congenital, Inflammation, MR-Cholangiography
Authors:
E. Boninsegna, G. A. Zamboni, R. Negrelli, R. Pozzi-Mucelli; Verona/IT
DOI:
10.1594/ecr2018/C-0602
Findings and procedure details
We have revised the most significant articles regarding congenital anomalies of pancreatic ductal system; we have also performed a search in the radiological and pathological databases of our Institution.
The most frequent condition is pancreas divisum,
depicted in about 10-15% of general population (Figure 1): it results from a failure of ventral and dorsal pancreatic bud fusion during embryological life [2]. The majority of the gland empties into the minor papilla through the dorsal (Santorini) duct.
Some patients are totally asymptomatic,
but several present recurrent pancreatic signs and symptoms: abdominal pain,
nausea,
vomiting,
elevated serum amylase and lipase levels [3]. Surgical or endoscopic procedures to ease pancreatic outflow are indicated in cases with severe manifestations.
MRCP allows noninvasive evaluation of the pancreatic duct without ERCP related risks; typical imaging feature is the main duct draining into the minor papilla [4]. This anomaly can be better appreciable after secretin administration [2]. Pancreas bifidum is a rare condition due to an incomplete ventral and dorsal pancreatic bud fusion: main pancreatic duct is Wirgung duct,
but at the level of the body or the tail of the gland an accessory parallel duct is visible,
joining the main duct at a various level [5] (Figure 2). Annular pancreas is a rare congenital anomaly: because of incomplete rotation of the ventral pancreatic bud there is a segment of the gland encircling the duodenum [6]. Symptoms,
when present,
are related to duodenal obstruction and recurrent pancreatitis; a surgical bypass procedure is indicated in selected patients.
MR and MRCP demonstrate pancreatic tissue and a thin annular duct encircling the second portion of the duodenum [7]. The ansa pancreatica is seen when there is obliteration of the proximal dorsal pancreatic duct,
which connects with the ventral duct through a S-shaped collateral [1] (Figure 3).
Other rare anatomical anomalies are anomalous junction of the pancreatic and bile ducts,
pancreatic hypoplasia and congenital pancreatic cysts.
Some of these conditions are totally asymptomatic and incidental findings,
whereas other are related to severe symptoms and require surgical or endoscopic correction.