This document discusses and provides images of different types of cystic pancreatic masses that can be seen on CT and MRI imaging. It describes 13 different examples, including true epithelial cysts seen in von Hippel-Lindau disease, pseudocysts, hemorrhagic pseudocysts, ectopic pancreatic pseudocysts, serous cystadenomas, mucinous cystic neoplasms, intraductal papillary mucinous neoplasms (IPMN), islet cell tumors, pseudopapillary tumors, pancreatic carcinomas, malignant IPMN, and pancreatic abscesses. For each example, it provides a short description and images demonstrating features of the cystic mass.

1. 82 Cystic Pancreatic Masses on
CT and MRI

2. CLINICAL IMAGAGING
AN ATLAS OF DIFFERENTIAL DAIGNOSIS
EISENBERG
DR. Muhammad Bin Zulfiqar
PGR-FCPS III SIMS/SHL

3. • Fig GI 82-1 True epithelial cysts. Contrast CT scan shows
multiple unilocular cysts (arrows) scattered throughout
an otherwise healthy-looking pancreas in this patient
with von Hippel-Lindau disease.167

4. • Fig GI 82-2 Pseudocyst. (A) Axial contrast CT
scan demonstrate a well-defined unilocular
cyst (arrow) in the tail of the pancreas. (B) T2-
weighted MR image shows the cyst (arrow)
with homogeneously bright signal intensity, a
finding that confirms that the lesion of a fluid-
filled unilocular structure.167

5. • Fig GI 82-3 Multiple pancreatic pseudocysts.
CT scan after the administration of contrast
material demonstrates four sharply
marginated, fluid-filled collections.

6. • Fig GI 82-4 Hemorrhagic pseudocyst. Contrast CT
scan shows a cystic mass containing an area of
high attenuation (arrow), a finding consistent
with recent hemorrhage.168

7. • Fig GI 82-5 Ectopic pancreatic pseudocyst. The
low-attenuation pseudocyst (PC) lies in the
superior recess of the lesser sac posterior to the
stomach (S). Note the dilated intrahepatic bile
ducts (arrow).

8. • Fig GI 82-6 Serous cystadenoma. (A) CT scan
shows a lobulated mass (arrow) of the
pancreatic head with typical central scar
(arrowhead) and lack of vascular encasement.
(B) T2-weighted MR image shows the internal
morphological features of the cyst, with high-
signal-intensity microcysts (arrows) that are
clearly distinguished from the dark central
scar (arrowhead).167

9. • Fig GI 82-7 Mucinous cystic neoplasm. A contrast
CT scan shows a large cystic mass (arrows) with
internal septa in the head of the pancreas. The
peripheral and septal calcification (arrowheads)
indicate the malignant nature of the lesion. (B) In
another patient, a contrast scan demonstrates a
well-circumscribed, 18-cm palpable mass within
the tail of the pancreas. There is enhancement on
the thin external septa and peripheral wall.164

10. • Fig GI 82-8 Intraductal IPMN. (A) Contrast CT
scan shows a small cyst (arrow) in the head of
the pancreas. (B) Coronal oblique MRCP
shows communication between the cyst
(arrow) and the main pancreatic duct
(arrowheads), a finding that helped establish
the diagnosis.167

11. • Fig GI 82-9 Islet cell tumor. CT scan in a patient
with a malignant primary neuroendocrine
tumor of the pancreas demonstrates a cystic
lesion in the pancreatic body with peripheral
mural nodules (arrows).167

12. • Fig GI 82-10 Pseudopapillary tumor. Contrast
CT scan shows a lesion in the body of the
pancreas with cystic areas and a solid
component or mural nodule (arrow).167

13. Fig GI 82-11 Pancreatic carcinoma. CT scan shows a solid tumor
with cystic degeneration (arrow).167

14. • Fig GI 82-12 Malignant IPMN. CT scan
demonstrates a multiseptated cyst with solid
components (arrow).167

15. • Fig GI 82-13 Pancreatic abscess. CT scan shows a
heterogeneous fluid collection with low attenuation
and irregular margins in the body and tail of the
pancreas. Note the high-attenuation debris (arrow)
within the lesion.168