Diagnostic ultrasound ( PDFDrive )

CHAPTER
7
The Pancreas
Thomas Winter and Maryellen R.M. Sun
SUMMARY OF KEY POINTS
• Knowledge of a few key scanning techniques will optimize
imaging of the entire pancreas.
• Understanding of the embryologic development, normal
anatomy, and anatomic variants of the
pancreas aids in detection and characterization
of disease.
• Ultrasound plays an important role in assessment of acute
and chronic pancreatitis, allowing for detection of
gallstones, bile duct dilation, and guiding aspiration and
drainage when needed.
• Computed tomography is the imaging modality of choice for
staging pancreatic cancer, but ultrasound can be used to
detect, characterize, and stage solid pancreatic neoplasms.
• Cystic pancreatic lesions are common, and it is important
to understand the benign and malignant features of these
lesions.
CHAPTER OUTLINE
ANATOMY AND SONOGRAPHIC
TECHNIQUE
Pancreatic Body
Pancreatic Head
Pancreatic Tail
Pancreatic Parenchyma
Fatty Pancreas
Embryology and Pancreatic Duct
Imaging Anatomic Variants
Peripancreatic Structures
ACUTE PANCREATITIS
Approach to Imaging
Ultrasound Findings
Complications
Acute Fluid Collections
Pseudocysts
Necrosis and Abscess
Treatment
Vascular Complications
CHRONIC PANCREATITIS
Approach to Imaging
Ultrasound Findings
Pseudocysts
Portal and Splenic Vein
Thrombosis
Masses Associated With Chronic
Pancreatitis
PANCREATIC NEOPLASMS
Periampullary Neoplasm
Pancreatic Carcinoma
Detection of Pancreatic Cancer
Ultrasound Findings
Resectability Imaging
Color Doppler Ultrasound
CYSTIC PANCREATIC LESIONS
Simple Pancreatic Cysts
Cystic Neoplasms
Serous Cystic Neoplasm
Intraductal Papillary Mucinous
Neoplasm
Mucinous Cystic Neoplasm
Solid-Pseudopapillary Tumor
Rare Cystic Tumors
OTHER PANCREATIC MASSES
Endocrine Tumors
Unusual and Rare Neoplasms
Lipoma
Metastatic Tumors
CONTRAST-ENHANCED
ULTRASOUND
Acknowledgment
Pancreatic sonography can be an eicient and valuable tool
in many common diseases, such as pancreatitis and pancreatic
neoplasm. Sonography is oten the irst test used in patients with
jaundice or abdominal pain. However, sonography is “technically
dependent” and necessitates understanding techniques to optimize
pancreatic sonography. Knowledge of sonographic indings in
common (and less common) pancreatic diseases is crucial to
obtaining good imaging and clinical outcomes in these patients.
ANATOMY AND SONOGRAPHIC
TECHNIQUE
Patient preparation is important in pancreatic sonography. An
8-hour fast before the study (usually overnight) is recommended,
but we allow our patients to drink water and take medicines
orally.
he three key regions of the pancreas are the head, body, and
tail. he visualization of each requires knowledge of pancreatic
anatomy, appropriate patient positioning, and oten the use of
multiple transducers. he pancreas lies obliquely in the anterior
pararenal space of the retroperitoneum, with the head caudal to
the body and tail. he pancreas is draped over the spine and aorta;
thus the neck and body are more supericial than the head and
tail. he more caudal position of the head oten leads to the technical
error of not visualizing the entire head on “transverse” scans. his
can be avoided by understanding the anatomy and by visualizing
the normal uncinate process behind the gastrocolic trunk on images
of the pancreatic head (Fig. 7.1). Knowledge of a few key scanning
techniques will optimize imaging of the entire pancreas.
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