Diagnostic ultrasound ( PDFDrive )

CHAPTER
11
The Adrenal Glands
Christina Marie Chingkoe, Olga R. Brook, and Deborah Levine
SUMMARY KEY POINTS
• The adrenal glands are responsible for maintaining
homeostasis and regulating hormonal production and
secretion within the body.
• The adrenal cortex is comprised of the zona glomerulosa,
fasciculata, and reticularis, which are responsible for
aldosterone, glucocorticoid, and androgen regulation,
respectively. The adrenal medulla regulates
catecholamines.
• Sonographic visualization of the right adrenal gland is best
through a transverse oblique and coronal view, using the
liver as an acoustic window. Sonographic visualization of
the left adrenal gland is best along the posterior axillary
line through an oblique coronal view, using either the
spleen or the left kidney as an acoustic window.
• Adrenal lesions can be localized via dynamic scanning:
adrenal glands are ixed relative to the great vessels and
move independently from the kidneys during deep
inspiration and upright positioning.
• Benign adrenal masses include adenomas (which may
be functional or nonfunctional), myelolipomas,
pheochromocytomas, cysts, hemorrhage, and
postinfectious calciications.
• Malignant adrenal masses include adrenocortical
carcinoma, metastases (most often from lung or breast
primary), and lymphoma.
• Ultrasound guidance can be used for percutaneous or
transhepatic biopsies, as well as for interventions including
radiofrequency, cryotherapy, or chemical ablation.
CHAPTER OUTLINE
ANATOMY AND PHYSIOLOGY
SONOGRAPHIC IMAGING AND
SCANNING TECHNIQUE
BENIGN ADRENAL MASSES
Adrenal Adenomas
Sonographic Features
Myelolipomas
Sonographic Features
Pheochromocytomas
Sonographic Features
Adrenal Cysts
Sonographic Features
Adrenal Hemorrhage
Sonographic Features
Infectious and Inlammatory Masses
Sonographic Features
MALIGNANT ADRENAL MASSES
Adrenocortical Carcinomas
Sonographic Features
Metastases
Sonographic Features
Lymphoma
Sonographic Features
RARE ADRENAL MASSES
MANAGEMENT OF ADRENAL
LESIONS
INTERVENTIONS
Ultrasound-Guided Biopsy and
Interventions
Endoscopic Ultrasound
Intraoperative Ultrasound
Acknowledgments
The adrenal glands are the smallest paired organs in the
abdomen, measuring approximately 4 to 6 cm in length, 2
to 3 cm in width, and 0.2 to 0.6 cm in thickness, equivalent to
4 g. 1,2 In spite of their size, the adrenal glands are responsible
for maintaining homeostasis and regulating hormonal production
and secretion within the body. he mainstay of adrenal gland
imaging is computed tomography (CT) because of its wide
availability, ease of anatomic visibility, and ability for lesion
characterization. However, adrenal lesions can be identiied during
sonographic evaluation of the abdomen, and because abdominal
sonography is a common examination, these lesions are relatively
frequently found on sonography. It is therefore important for
the radiologist to have a thorough understanding of the role that
ultrasound can play in adrenal gland imaging, including the
diagnosis and management of lesions.
ANATOMY AND PHYSIOLOGY
he adrenal glands are located in the perirenal space, superior
to the kidneys, at the level of the 11th or 12th thoracic rib, lateral
to the irst lumbar vertebra. he adrenal glands are comprised
of a superoanteromedial ridge, an oten larger and more
superiorly located medial limb, as well as a smaller more inferiorly
located lateral limb. Although the shape of the adrenal glands
can vary, the thickness of the limbs, particularly the lateral limbs,
remain relatively constant and therefore are the most useful
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