CT and MRI of Pancreatic Cystic Lesions

Pancreatic cystic lesions are frequently encountered in routine radiological practice. Majority of pancreatic cystic lesions are a symptomatic and detected as incidental findings in individuals. The term pancreatic cystic lesion (PCL) encompasses a large variety of lesions ranging from benign congenital cysts to frankly malignant masses with a predominant cystic appearance on imaging. Although sonography is often the screening modality, cross-sectional techniques including CT are routinely performed to diagnose these cystic lesions. MRI with its excellent soft tissue resolution is often used as a problem-solving tool to better characterize and prognosticate these lesions. In this chapter, we shall discuss in detail the role of these modalities in establishing a definitive diagnosis of PCLs. In addition, we shall also differentiate various benign and malignant pathologies based on characteristic imaging appearance. We also propose a stepwise algorithmic approach to a PCL encountered on imaging that will help radiologists and gastroenterologists alike in reaching a conclusive diagnosis.