Author Ashley Davidoff MD

Collaborators   Charles Allison MD Adam Asarch MSII  David Lee MD Scott Tsai MD Sam Yam PhD.

Approach

Since the normal aging process of the pancreas results in fatty infiltration of the gland finding an echogenic or fatty pancreas on routine imaging is not uncommon.  There is a range of normal from mild where the infiltrating fat creates a lobular appearance to the surface of the gland to severe infiltration where the pancreas is almost totally replaced by fat and the glandular tissue is visible as strands of tissue scattered throughout the gland.  In the latter instance there is a surprising absence of functional significance.  In patients with cystic fibrosis the pancreas is totally replaced and even strand of tissue are not seen.  It is in these instances that functional changes may be seen.  There are rare instance of lipomas in the gland which are easily recognized.  Therefore fat in the pancreas in general does not present as a challenge in differential diagnosis.  In the young patient with severe fatty change ask about cystic fibrosis, and in the patient with a lipoma, ask about associated syndromes.  There are only a few isolated reports of lipomas in the literature.

Differential Diagnosis

aging process 99.9%

cystic fibrosis

lipoma

The transverse section through the pancreas shows an echogenic pancreas caused by infiltration of retroperitoneal fat into the age related involution of the pancreatic parenchyma.  This is a normal and common finding,  and usually has no clinical nor functional significance.  29495 Courtesy Ashley Davidoff MD

This CTscan through the tail of the pancreas shows involutional change of the tail of the pancreas characterized by the nodular appearance of the borders of the pancreas.  This is a normal aging process whereby the involuting pancreatic parenchyma gets replaced by the retroperitoneal fat which has free access into the pancreas since there is no formal protective capsule surrounding the pancreas. 39807 Courtesy Ashley Davidoff MD

This CTscan through the pancreas shows a dominance of fat, with only connective tissue strands and  blood vessels in this patient with cystic fibrosis.  Note the complex ascites and thickening in the anterior pararenal space.  40625 Courtesy Ashley Davidoff MD

This CTscan through the liver and pancreas shows severe fatty change in the body and tail of the pancreas associated with severe steatosis of the liver.  Air in the biliary system is of incidental note.   This patient has cystic fibrosis. 22581 Courtesy Ashley Davidoff MD

The following series reflects two levels of the case described above.

This CTscan through the liver and pancreas shows severe fatty change in the entire pancreas.  Image a shows diffuse fatty change of the neck, body and tail, with image c showing a pink overlay of the pancreas.  Image b shows a similar fatty infiltration in the head and uncinate process with image d representing the overlay of these structures. 22584c04 Courtesy Ashley Davidoff MD

This CT scan shows an unusual pattern of fatty change of the pancreas in this patient with known von Hippel-Lindau syndrome.  Noted is the severe fatty infiltration in the body and tail and total sparing of the neck and head.  Associated findings include a variety of cysts in the uncinate process with both simple and complex characteristics.  18378b Courtesy Ashley Davidoff MD

The following series reflects two levels of the case described above both without and  with contrast.

This CT scan shows a variety of findings in the pancreas in a patient with known von Hippel-Lindau syndrome.  Image a and b are non contrast scans while image c and d are the correlative scans with contrast.  There are a variety of cysts in the uncinate process (a,c), and a solid mass in the head with central calcification (b), that enhances significantly with contrast. (cystadenoma) An unusual pattern of fatty change of the pancreas in this patient is noted with severe fatty infiltration in the body and tail and total sparing of the neck and head.  18382c01 Courtesy Ashley Davidoff MD

The first image of this series (a), reveals a colon cut off sign and is associated with a mild degree of induration around the pancreas best seen in c. The pancreas itself is enlarged and heterogeneous with a few small complex structures that are too small to resolve, seen best in b and c.  A large lipoma is seen in the head of the pancreas in e.  The right kidney has a fatty mass in its upper pole consistent with an angiomyolipoma.  The overall picture suggests a diagnosis of von Hippel–Lindau syndrome.  40200c01 Courtesy Ashley Davidoff MD