This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Radiology
"Strings of pearls" appearance is seen in? 
Select and explain. 
A. SAIO, B. Gallstone ileus, C. Chronic pancreatitis, D. Duodenal perforation
C: Chronic pancreatitis
Answer: C: Chronic pancreatitis 
Explanation: Chronic pancreatitis is characterized by irregularities of of the pancreatic ducts, ductal strictures, and area of duct dilation. The major as well as the side branch ducts may be involved. For unexplained reason, some patients with chronic pancreatitis develop dilated main pancreatic ducts (large ductal disease), whereas others retain ducts of normal or even smaller than normal calibers (small ductal disease). Some patients with chronic pancreatitis can be shown to have major ducts that have the appearance of a "chain of lakes" or a "strings of pearls" that is the result of segment of dilated duct separated by areas of ductal stricture. Ref: Sutton's Radiology 7/e, Volume 1, Page 798