[Chronic pancreatitis : Characterization and differentiation from pancreatic cancer]. / Chronische Pankreatitis : Charakterisierung und Differenzierung zum Pankreaskarzinom.

CLINICAL/METHODOLOGICAL ISSUE: Chronic pancreatitis (CP) is a long-lasting inflammation of the pancreas that changes the normal structure and function of the organ. There are a wide range of inflammatory pancreatic diseases, of which some entities, such as focal pancreatitis (FP) or "mass-forming pancreatitis," can mimic pancreatic ductal adenocarcinoma (PDAC). As a consequence, a misdiagnosis can lead to avoidable and unnecessary surgery or delay of therapy. STANDARD RADIOLOGICAL METHODS: The initial imaging method used in pancreatic diseases is ultrasound due to its availability and low cost, followed by contrast-enhanced computed tomography (CE-CT), which is considered a workhorse in the diagnostic work-up of diseases of the pancreas. Magnetic resonance imaging (MRI) and/or MR cholangiopancreatography (MRCP) can be used as a problem-solving tool to distinguish between solid and cystic lesions, and to rule out abnormalities in the pancreatic ducts, such as those associated with recurrent acute pancreatitis (AP) or to show early signs of CP. MRCP has essentially replaced diagnostic endoscopic retrograde cholangiopancreatography (ERCP) in the initial assessment before any therapeutic intervention. PRACTICAL RECOMMENDATION: The following review article summarizes the relevant features of CT and MRI that can help to make the diagnosis of CP and to aid in the differentiation between focal pancreatitis and PDAC, even in difficult cases.

[Benign focal hepatic lesions]. / Benigne fokale Leberläsionen.

A profound knowledge of the various benign focal hepatic lesions and selection of the most suitable radiological examination modality is essential for achieving an accurate characterization of a hepatic lesion and in turn will determine the further patient management. This will avoid unnecessary agitation to both patient and the referring clinician and limits time-consuming, costly and risky biopsies to an absolute minimum. The following article will discuss the typical and atypical appearances of the most frequent and clinically relevant benign focal hepatic lesions with ultrasound, computed tomography and magnetic resonance imaging.

[Diseases of the peritoneum and mesenterium]. / Erkrankungen von Peritoneum und Mesenterium.

Peritoneal diseases can be seen in the different imaging modalities either as fluid collections or solid tumors along the ligaments, mesenteries, and spaces of the peritoneal cavity. The broad spectrum of different abnormalities includes inflammatory, infectious, traumatic, and neoplastic diseases. In this article, a large variety of peritoneal abnormalities such as ascites, peritonitis, intraperitoneal hemorrhage, and both primary and secondary peritoneal tumors are discussed. The different imaging modalities, characteristic radiological features, and typical pathways of anatomic spread are explained.

[Peritoneum and mesenterium. Radiological anatomy and extent of peritoneal diseases]. / Peritoneum und Mesenterium: Radiologische Anatomie und Ausbreitungswege intraabdomineller Erkrankungen.

The abdominal cavity is subdivided into the peritoneal cavity, lined by the parietal peritoneum, and the extraperitoneal space. It extends from the diaphragm to the pelvic floor. The visceral peritoneum covers the intraperitoneal organs and part of the pelvic organs. The parietal and visceral layers of the peritoneum are in sliding contact; the potential space between them is called the peritoneal cavity and is a part of the embryologic abdominal cavity or primitive coelomic duct. To understand the complex anatomical construction of the different variants of plicae and recesses of the peritoneum, an appreciation of the embryologic development of the peritoneal cavity is crucial. This knowledge reflects the understanding of the peritoneal anatomy, deep knowledge of which is very important in determining the cause and extent of peritoneal diseases as well as in decision making when choosing the appropriate therapeutic approach, whether surgery, conservative treatment, or interventional radiology.