Transcript Document
ADRENAL MASSES: MR IMAGING
FEATURES WITH PATHOLOGIC
CORRELATION
By :
Nour Eldin Mohammed
Ref: Khaled M. Elsayes, et al , 2004, Radiographics
Normal Anatomy
The adrenal glands are two
small, yellowish bodies located
in the perirenal space,
immediately anterosuperior to
the upper pole of the kidneys.
They are very vascular and
receive blood supply from the
superior, middle, and inferior
suprarenal arteries
The adrenal gland is
composed of an outer
cortex and thinner inner
medulla.
The cortex is further
subdivided into three
zones: outer zona
glomerulosa, middle zona
fasciculata, and inner zona
reticularis
Normal MRI Appearance
The right adrenal gland is
located posterior to the inferior
vena cava and superior to the
upper pole of the right kidney.
The left adrenal gland is
anteromedial to the upper pole
of the kidney and posterior to
the pancreas
Normal adrenal glands range
from 2 to 6 mm in thickness
and from 2 to 4 cm in length
Fat-containing Adrenal
Masses
Fat-containing adrenal masses can be classified
into two main types:
those that contain intracellular fat (eg,
adenoma)
2. and those with macroscopic fat (eg,
myelolipoma).
1.
Adrenal Adenoma
The most common adrenal lesions.
Characterised by the presence of intracellular lipid.
Chemical shift imaging is the most reliable technique for
diagnosing adrenal adenoma with loss of signal intensity
on out-of-phase images.
Uniform enhancement with contrast enhanced images is
typical of adenomas.
Cystic changes, hemorrhage, or variation in vascularity
lead to small, rounded foci of altered signal intensity.
Axial in Phase MRI
Axial out of phase MRI
Myelolipoma
The myelolipoma is an uncommon benign tumor
composed of mature adipose tissue and hematopoietic
tissue.
Mostly discovered accidentally.
The fatty component of this tumor is hyperintense on T1weighted images.
With loss of signal intensity of the fatty component on
Fat-Suppressed Technique.
Axial T1 MRI
Axial T1 with Fat
Suppressed Technique
Cystic Masses
These include :
1. Simple Cysts
2. Pseudocysts
3. Lymphangioma
Simple Cysts
T1 Coronal MRI
T2 Coronal MRI
Pseudocysts
Pseudocysts typically arise after an episode of adrenal
hemorrhage and do not have an epithelial lining.
Have a complicated appearance on MR images,
manifesting with septations, blood products, or a softtissue component secondary to hemorrhage or
hyalinized thrombus.
Peripheral curvilinear calcification may be present.
Axial T1 with Contrast
Coronal T2 MRI
Lymphangioma
Low signal intensity at T1-weighted imaging and high
signal intensity at T2-weighted
Hypervascular Lesions
(Pheochromocytoma)
It arises from the adrenal medulla.
10% of pheochromocytomas are bilateral,10% are
extraadrenal,10% occur in children, and 10% are
malignant
Pheochromocytomas do not contain a substantial
amount of cytoplasmic lipid, So they maintain their
signal intensity on out-of-phase GRE chemical shift
images.
Most pheochromocytomas demonstrate high signal
intensity on T2-weighted images (light bulb sign).
Axial T1 in Phase MRI
Contrast-enhanced Image
Axial T1 out of Phase MRI
Malignant Neoplasms
Adrenocortical Carcinoma
Adrenal Lymphoma
Metastases
Adrenocortical Carcinoma
a rare tumor.
Age : 30 - 70
Large size
Can manifest as a hyperfunctioning mass
causing Cushing syndrome or Conn
syndrome.
Other manifestations include an
abdominal mass and abdominal pain.
Sagittal 3D contrastenhanced MRI
Coronal T2-weighted MRI
Adrenal Lymphoma
More with non-Hodgkin lymphoma
Bilateral involvement occurs in 50% of
patients .
Characterized by low signal intensity on T1 WI
and heterogeneous high signal intensity on
T2 WI , with minimal progressive
enhancement after administration of
contrast material.
Axial T1-weighted MRI
Axial T2-weighted MRI
Metastases
The most common malignant lesions involving
the adrenal gland.
Found in up to 27% of patients with Carcinomas
at autopsy.
Common primary sites of tumors that
metastasize to the adrenal glands include the
lung, bowel, breast, and pancreas.
Usually bilateral but may also be unilateral.
Contrast Enhanced T1 Image Of Metastatic
Deposit From Renal Cell Carcinoma
Pediatric Neoplasms
Neuroblastoma
Ganglioneuroblastoma
Neuroblastoma
The 2nd most common pediatric abdominal
mass (after Wilms tumor).
Representing 5%–15% of all malignant tumors in
children .
Arises from the neural crest in the adrenal
medulla or along the sympathetic chain.
Usually demonstrates heterogeneous low signal
intensity on T1-weighted images, high signal
intensity on T2-weighted images , and
enhancement after administration of contrast
material.
Calcification is present in 80%–90% of the
lesions
Coronal unenhanced T1 MRI
Axial T2 MRI
Ganglioneuroblastoma
Intermediate in malignancy between that of
neuroblastoma and ganglioneuroma
arise from the neural crest.
Ganglioneuroblastoma are smaller and more
well defined than neuroblastoma
Demonstrates Intermediate signal intensity on
T1 WI and heterogeneously high signal intensity
on T2 WI, with heterogeneous enhancement
after administration of contrast material.
T1-WI shows a heterogeneous mass with
intermediate signal intensity
Thank you