Diagnostic Imaging of Adrenal Glands

1. Genito-Urinary System
Adrenal Glands

2. Mohamed Zaitoun
Assistant Lecturer-Diagnostic Radiology
Department , Zagazig University Hospitals
Egypt
FINR (Fellowship of Interventional
Neuroradiology)-Switzerland
zaitoun82@gmail.com

5. Knowing as much as
possible about your enemy
precedes successful battle
and learning about the
disease process precedes
successful management

6. Adrenal Glands
a) Incidental Adrenal Mass
b) Bilateral Adrenal Masses
c) Adrenal Calcification

7. Anatomy of the Adrenal Gland
a) Arterial Supply :
-Superior adrenal artery: branch of inferior
phrenic artery
-Middle adrenal artery: branch of the aorta
-Inferior adrenal artery: branch of the renal
artery

9. b) Venous Drainage :
-Each gland is drained by a single vein that
enters into the :
Inferior vena cava on the right
Renal vein on the left

10. c) Physiology :
-Cortex divided into 3 zones :
Zona glomerulosa (aldosterone)
Zona fasciculata (ACTH dependent)
Zona reticularis (cortisol)
-Medulla (epinephrine, norepinephrine)

11. d) Imaging Appearance :
-Y configuration : each adrenal gland consists of an
anteromedial ridge (body) and two posterior limbs best
seen by CT/MR
-Posterior limbs are close together superiorly but spread
out inferiorly
-Right adrenal lies adjacent to IVC throughout its extent
-Left adrenal lies adjacent to splenic vessels at its cephalad
margin
-Size :
Limbs: 3 to 6 mm thick
Length of entire adrenal: 4 to 6 cm
Width of entire adrenal: <1 cm
Weight: 4 to 5 g/gland

14. Coronal T1-weighted, three-dimensional, GRE MR image obtained with
VIBE shows the normal inverted Y shape of the right adrenal gland
(arrow)

15. a) Incidental Adrenal Mass :
1-Functioning Tumors
2-Malignant Tumors
3-Benign

16. 1-Functioning Tumors :
a) Pheochromocytoma
b) Conn’s Adenoma
c) Cushing’s Adenoma
d) Adrenal Carcinoma

17. a) Pheochromocytoma :
1-Incidence
2-Associations
3-Radiographic Features

19. 1-Incidence :
-Is an uncommon tumor of the adrenal gland
-The tumors are said to follow a 10% rule :
10% are extra-adrenal
10% are bilateral
10% are malignant
10% are found in children
10% are familial
10 % are not associated with hypertension

20. 2-Associations :
-The majority of cases are sporadic
-In 5-10% of cases , a pheochromocytoma is a
manifestation of an underlying condition including :
a) MEN II (both MEN IIa and MEN IIb) :
-MEN IIa : medullary thyroid carcinoma ,
pheochromocytoma & parathyroid adenoma
-MEN IIb : medullary thyroid carcinoma ,
pheochromocytoma , oral ganglioneuromas & other soft
tissue tumors
b) VHL
c) Sturge-Weber Syndrome
d) TS

21. 3-Radiographic Features :
-Usually large > 5 cm with marked contrast
enhancement
-It should be noted that in patients with suspected
pheochromocytoma contrast may be
contraindicated as it could precipitate a
hypertensive crisis
a) CT :
-On CT pheochromocytomas are large usually
heterogeneous masses with areas of necrosis
and cystic change with marked contrast
enhancement

22. Pheochromocytomas in a 35-year-old woman with hypokalemia, a family history of
pheochromocytoma, and a new diagnosis of von Hippel–Lindau syndrome, axial
arterial phase (a) and coronal arterial phase volume-rendered (b) CT images,
obtained for evaluation of right upper quadrant pain, show small incidental bilateral
adrenal masses (arrow), the degree of vascularity resulted in a differential diagnosis
of metastatic hypervascular tumor or pheochromocytoma, pathologic analysis
revealed bilateral pheochromocytomas; the lesion on the right measured 2 cm, and
the two masses in the left adrenal gland measured 0.4 cm and 0.6 cm

23. Pheochromocytoma with pathologically proved hemorrhage and necrosis in a 39-year-old
woman, coronal precontrast volume-rendered (a) and axial postcontrast (b) CT
images show a large, well-defined mass with higher attenuation inferiorly that
compresses the liver and right kidney, on the contrast-enhanced image, enhancing
septa and multiple cystic areas are seen. Classically a vascular mass,
pheochromocytoma can also be cystic, particularly when the tumor is large, as in this
case

24. Pheochromocytomas in a 47-year-old woman with a history of neurofibromas
resected from both wrists who presented with abdominal pain, axial (a) and
coronal multiplanar reformation (b) images from contrast-enhanced CT
show bilateral adrenal masses (arrows), which are predominantly cystic on
the left (white arrowheads) and solid with cystic components (black
arrowheads) on the right, fine-needle aspiration performed in one mass
demonstrated a pheochromocytoma

25. Pheochromocytoma with rapid washout, axial portal venous phase (a) and
delayed phase (b) CT images show a small solid mass in the right adrenal
gland, the RPW of the adrenal nodule is 52%, a value that can be seen with
adenoma; however, the portal venous phase attenuation of 164 HU
suggests a pheochromocytoma, such high enhancement levels are not
characteristic of adenoma but are seen with some pheochromocytomas

26. Necrotic pheochromocytoma in a 42-year-old man, coronal arterial
phase (a) and venous phase (b) volume-rendered images from
contrast-enhanced CT show a large (>20 cm) hypervascular right
suprarenal mass, the mass has central necrosis and compresses
the right kidney inferiorly

27. b) MRI :
*T1 :
-Slightly hypointense to the remainder of the
adrenal
*T2 :
-Markedly hyperintense (lightbulb sign) , this is a
helpful feature
*T1+C :
-Heterogenous enhancement
c) Nuclear Medicine : MIBG
-Abnormal uptake

28. Axial T1-weighted in-phase MR image (a), out-of-phase MR image (b), and
three-dimensional GRE contrast-enhanced MR image with VIBE (c) show a
pheochromocytoma (arrow), the pheochromocytoma shows the typical
features of no loss of signal intensity on the out-of-phase image and intense
enhancement on the contrast-enhanced image

29. b) Conn’s Adenoma :
1-Incidence
2-Radiographic Features

30. 1-Incidence :
-Accounts for 70 % of Conn’s syndrome
-30 % of Conn’s syndrome due to
hyperplasia which can be occasionally
nodular and mimic an adenoma
2-Radiographic Features :
-Usually small < 2 cm
-Relatively low dense

31. c) Cushing’s Adenoma :
1-Incidence
2-Radiographic Features

32. 1-Incidence :
-Accounts for 20 % of Cushing syndrome
-80 % of Cushing syndrome is due to
excess ACTH from pituitary tumor or
ectopic source (small cell carcinoma ,
pancreatic islet cell , carcinoid medullary
carcinoma of the thyroid & thymoma)
2-Radiographic Features :
-Usually > 2 cm in diameter

33. d) Adrenal Carcinoma :
-50 % are present as functioning tumor
-Cushing's syndrome most common clinical
manifestation

34. 2-Malignant Tumors :
a) Metastases
b) Carcinoma
c) Lymphoma
d) Neuroblastoma

35. a) Metastases :
1-Primary sites
2-Radiographic Features

37. 1-Primary sites :
-Lung :
Small cell carcinoma : 90% of adrenal masses
detected by CT screening represent metastases
Non–small cell carcinoma : 60% of adrenal
masses
-Breast
-Kidney
-Bowel
-Ovary
-Melanoma

38. 2-Radiographic Features :
-Adrenal mass usually > 2-3 cm with
irregular margins
-Bilateral adrenal masses
-Heterogeneous enhancement
-In the presence of a known primary
malignant tumor many adrenal masses
are benign (40 % are metastases)

39. Adrenal metastases in a 61-year-old man with hepatocellular carcinoma,
axial (a) and coronal volume-rendered (b) images from contrast-enhanced
CT show primary hepatic carcinoma in the right lobe, along with large
bilateral adrenal masses, the high-attenuation components of the adrenal
lesions probably represent contrast material from prior chemoembolization
or calcifications

40. Metastatic renal cell carcinoma in a 67-year-old woman, coronal arterial
phase (a) and venous phase (b) volume-rendered CT images show
widespread metastatic disease involving the liver, lung, adrenal gland, and
bones, the liver metastases are hyperattenuating and are well seen on the
arterial phase image but become less conspicuous on the venous phase
image

41. Adrenal metastasis in a 61-year-old man with a history of left nephrectomy for
renal cell carcinoma, coronal arterial phase (a) and delayed
phase (b) volume-rendered images from contrast-enhanced CT show a
hypervascular right adrenal mass with central necrosis, a finding consistent
with pheochromocytoma or a metastasis from renal cell carcinoma, the latter
diagnosis was proved at pathologic analysis after resection; however, the
enhancement pattern is similar to that of necrotic pheochromoctyoma

42. b) Carcinoma :
1-Incidence
2-Radiographic Features

44. 1-Incidence :
-50 % are present as functioning tumor
-Cushing's syndrome most common clinical
manifestation

45. 2-Radiographic Features :
-Mass usually >5 cm at time of diagnosis
-Central area of low attenuation due to
tumor necrosis
-Heterogeneous enhancement because of
areas of necrosis , hemorrhage
-50% have calcifications
-Hepatic , nodal or venous spread

46. Adrenocortical carcinoma in a 62-year-old woman with hypertension, virilization, and an enlarging
abdominal mass, coronal arterial phase (a) and venous phase (b) volume-rendered CT images
show a large left suprarenal mass with hypervascularity and necrosis on the arterial phase image
and some areas of mild enhancement on the venous phase image, the mass abuts the left
hemidiaphragm, with left pleural effusion and left lung atelectasis, and is inseparable from the left
kidney, at surgery, which included left nephrectomy, a portion of the left hemidiaphragm was
resected and the left lower lobe was partially decorticated, pathologic analysis revealed a
malignant adrenocortical neoplasm

47. Primary adrenocortical carcinoma in a 55-year-old woman, coronal volume-
rendered images from contrast-enhanced CT show a nearly 15-cm right
adrenal mass that displaces the right kidney inferolaterally and invades the
inferior vena cava (IVC) medially (arrowheads in a), tumor thrombus
extends into the intrahepatic IVC (arrows in b)

48. 61-year-old woman who presented with left lower quadrant pain, arterial phase
(A), portal venous phase axial (B), and coronal (C) images show well-
encapsulated large 13.5-cm mass lesion arising from left adrenal gland with
internal calcifications but containing no focal fat, pancreas and left kidney
are displaced by mass, but there is no evidence of invasion into adjacent
vascular structures, on resection this mass represented adrenocortical
carcinoma

49. Sagittal T1-weighted three-dimensional contrast-enhanced GRE MR image
obtained with VIBE (a) and coronal T2 obtained with half-Fourier
RARE (b) show a large mass involving the right adrenal gland, the mass
exhibits heterogeneous low signal intensity on the T1 and high signal
intensity with a heterogeneous pattern of contrast enhancement and areas
of necrosis (arrow in b) on the T2

50. c) Lymphoma :
-Lymphoma can involve the adrenal gland
secondarily or arise as a primary adrenal
tumor (uncommon)
-Lymphadenopathy will be seen elsewhere

51. Adrenal lymphoma in a 67-year-old man with an adrenal mass, imaging was
performed for diagnosis and staging, axial arterial phase (a) and coronal
arterial phase volume-rendered (b) CT images show an 11-cm mass in the
left adrenal bed, the mass invades the left hemidiaphragm, encases the
celiac and renal arteries, and displaces the aorta, the mild degree of organ
displacement despite the size of the mass and the infiltrative appearance
are suggestive of lymphoma; the diagnosis was confirmed at core biopsy

52. Axial T1-weighted in-phase (a) and out-of-phase (b) MR images show
bilateral lymphomatous deposits, the deposits have low signal
intensity, and the signal intensity does not decrease on the out-of-
phase compared with the in-phase image

53. d) Neuroblastoma :
-> 5 cm
-Calcification in 90 %
-Extends across midline

54. Neuroblastoma with disease crossing midline

56. Neuroblastoma (a, b) Coronal unenhanced T1 (a) and axial T2
obtained with inversion recovery (b) show a right adrenal tumor, the
tumor is predominantly hypointense on the T1 and has areas of
high-signal-intensity hemorrhage (arrow in a), the tumor is
hyperintense on the T2

57. 3-Benign :
a) Non-Functioning Adenoma
b) Myelolipoma
c) AML
d) Cyst
e) Adrenal Hemorrhage
f) Granulomatous Disease

58. a) Non-Functioning Adenoma :
-The majority of lesions are not functioning. Although CT
does not allow differentiation of functioning from
nonfunctioning masses, the presence of contralateral
adrenal atrophy suggests that a lesion may be
functioning, because pituitary adrenocorticotropic
hormone secretion is suppressed by elevated cortisol
levels
-The precontrast attenuation varies according to the
presence or absence of lipid, with mean attenuation in
the range of −2 to 16 HU in lipid-rich adenomas and
higher attenuation (20–25 HU) seen in the setting of
lipid-poor adenomas
-Lipid-poor adenomas represent 10%-40% of adenomas
-Regardless of lipid content, adenomas typically
demonstrate rapid washout, which is defined as an APW
of more than 60% and an RPW of more than 40% on
delayed images

59. -Radiographic Features :
1-CT :
-Mass 1 to 5 cm
-< 0 HU : diagnostic of adenoma (due to fat)
-0 to 10 HU : diagnosis almost certain (follow-up or MRI)
-Calcification rare
-Slight enhancement with IV contrast
-Rarely, an adenoma can hemorrhage, usually in a patient
receiving anticoagulant therapy, the presence of
hemorrhage results in regions of higher attenuation and
heterogeneity, at CT, heterogeneity and regions of
increased attenuation have been shown to correlate with
hemorrhage at pathologic analysis, before liquefaction,
the precontrast attenuation will be higher than 10 HU

60. Adrenal adenomas in a 62-year-old man with incidentally detected bilateral
adrenal nodules, clinical assessment revealed subclinical Cushing
syndrome, coronal contrast material–enhanced multiplanar reformation CT
image shows small (<2 cm) bilateral adrenal nodules, the relative
percentage washout (RPW) was more than 50% for both nodules, a finding
compatible with adenomas, follow-up CT performed 7 months later showed
stability of the lesions

61. 2.1-cm left adrenal mass was discovered incidentally on contrast-
enhanced computed tomography (CT), because the mass could not
be characterized on the contrast-enhanced CT, this unenhanced CT
was performed. It shows that the lesion (arrows) is of low
attenuation (6 HU), which is consistent with a lipid-rich adenoma

62. Lipid-poor adenoma in a 45-year-old woman who underwent CT for characterization of an
adrenal mass, axial precontrast (a), coronal portal venous phase volume-
rendered (b), and coronal delayed phase volume-rendered (c) CT images show a
well-defined left adrenal mass less than 2 cm in diameter, the attenuation
measurements were 22 HU on the precontrast image, 64 HU on the portal venous
phase image, and 26 HU on the delayed phase image, for an absolute percentage
washout (APW) of 90% and an RPW of 59%, the findings were consistent with a lipid-
poor adenoma

63. Adrenocortical adenoma with hemorrhage in a 78-year-old woman with an adrenal mass
that enlarged from 3 cm to 4 cm over 4 years, coronal pre-contrast volume-
rendered (a), coronal venous phase volume-rendered (b), and axial delayed
phase (c) CT images show a 3.2 × 3.9-cm inhomogeneous mass in the left adrenal
gland, some regions of fat attenuation are identified on the precontrast and delayed
phase images (−12 HU in c), there are central areas of higher attenuation that
measured 69 HU on the delayed phase image, with an appearance suggestive of
hemorrhage into the mass, resection revealed an adrenocortical adenoma with
central organized hemorrhage

64. Right adrenal gland shows 1.1-cm lesion measuring 8 HU on
unenhanced (A and B), 40 HU on dynamic phase (C and D), and 18
HU on 10-minute delayed phase images (E and F), these density
and washout properties are consistent with adrenal adenoma

65. 2-MRI :
-Fat-suppression techniques are used to
determine if a given lesion contains fat
(e.g., in phase/out of phase imaging , spin-
echo fat-suppression imaging) , if a lesion
contains fat , it is considered an adenoma

66. Axial in-phase (a) and out-of-phase (b) MR images show an adrenal
adenoma (arrow), which exhibits the typical decrease in signal
intensity on the out-of-phase image

67. Axial T1-weighted out-of-phase MR image shows an adrenal adenoma
(black arrow) with a focal area of high-signal-intensity hemorrhage
(white arrow)

68. **N.B. :
-Chemical shift MRI uses a technique based on
hydrogen and fat protons, which resonate at
different frequencies
-By using different time parameters during the
same MRI examination, it is possible to identify
lipid-rich adenomas
-These adenomas show signal loss on out-of-
phase imaging, as opposed to imaging when the
protons are in phase, in contrast, nonadenomas
do not show signal loss on out-of-phase imaging

69. Magnetic resonance imaging incidentally detects a 2.5-cm adrenal
mass (arrows) on (A) the in-phase image and signal dropout
on (B) the opposed out-of-phase image, these findings are
consistent with a lipid-rich adenoma

70. b) Myelolipoma :
-Very rare
-Area of obvious fat mass (low negative
attenuation)
-May enhance with contrast administration
-Calcification , 20%

71. Myelolipoma in a 40-year-old man with metastatic medullary carcinoma
of the thyroid, coronal multiplanar reformation image from contrast-
enhanced CT shows a 5-cm left adrenal mass predominantly
composed of fat (arrows), an appearance diagnostic of a
myelolipoma

72. Myelolipoma in a 31-year-old woman with an adrenal mass, which was
incidentally noted during work-up for chronic anemia and infertility,
coronal volume-rendered CT image shows a 6.5-cm right adrenal
mass composed of soft tissue and fat, an appearance consistent
with a myelolipoma

73. Myelolipoma in a 59-year-old woman with a history of long-standing hypertension, a
normal urinary metanephrine level, and no clinical evidence of hypercortisolism.
Coronal precontrast (a) and arterial phase (b) multiplanar reformation images from
contrast-enhanced CT show an 8-cm left adrenal mass containing multiple foci of fat
and punctate calcifications; there was mild enhancement on venous phase images,
after resection, pathologic analysis revealed a benign vascular lesion with adipose
tissue, findings consistent with a myelolipoma

74. (a, b) Axial T1-weighted MR images obtained without fat suppression (a) and
with fat suppression (b) show typical MR imaging features of right adrenal
myelolipoma, the fatty component of the myelolipoma (arrow in a) shows a
decrease in signal intensity on the fat-suppressed image

75. Loss of signal on out-of-phase

76. c) AML :
-Very rare

77. d) Cyst :
1-Classification
2-Radiographic Features

78. 1-Classification :
a) Endothelial cyst , 40%
b) Pseudocyst (hemorrhage) , 40% , may
contain calcified rim
c) Epithelial cyst , 10%
d) Parasitic cysts (Echinococcus) , 5%

79. 2-Radiographic Features :
-Well defined water density
-Mural calcification (15%) , especially in
pseudocysts and parasitic cysts

80. (a, b) Coronal T1-weighted in-phase (a) and T2 half-Fourier
RARE (b) MR images show an oval, well-circumscribed, right
adrenal cyst (arrow in b) with a thin wall (arrowhead in b), the cyst
has a typical appearance, showing low signal intensity at T1 and
high signal intensity at T2

81. Axial T2-weighted MR image obtained with inversion recovery shows a
left adrenal pseudocyst, note the soft-tissue component in the wall
and the posteriorly located calcification (arrow)

82. Hemorrhagic complicated adrenal cyst, (a, b) Coronal T2 obtained with
half-Fourier RARE (a) and axial contrast-enhanced VIBE
image (b) show a left adrenal mass with areas of signal intensity
similar to that of blood

83. e) Adrenal Hemorrhage :
1-Incidence
2-Etiology
3-Radiographic Features

84. 1-Incidence :
-More common in neonates than adults
2-Etiology :
a) Hemorrhagic tumors
b) Severe trauma
c) Anticoagulation
d) Severe stress (surgery , sepsis , burns &
hypotension)

85. 3-Radiographic Features :
a) Acute hematoma :
-High CT density (>40 HU)
-Enlarged adrenal gland
b) Old hematoma :
-Liquefaction
-Fluid-fluid level
-May evolve into pseudocyst

86. Axial unenhanced T1-weighted three-dimensional GRE MR image
obtained with VIBE demonstrates a right adrenal gland with a high-
signal-intensity rim (arrows), a finding that is consistent with
subacute hematoma

87. f) Granulomatous Disease :
-Most common causes are TB ,
histoplasmosis , blastomycosis ,
meningococcus and echinococcus
-Present as diffuse enlargement or as
discrete mass
-Can have a central cystic component with
or without calcifications

89. b) Bilateral Adrenal Masses :
1-Metastases , in 15 %
2-Pheochromocytoma , in 10 %
3-Hyperplasia :
-Bilateral adrenal enlargement but usually not seen
on CT
4-Spontaneous Adrenal Hemorrhage
5-Lymphoma
6-Granulomatous Disease

90. c) Adrenal Calcification :
1-Pseudocyst , Parasitic cyst
2-Carcinoma
3-Addison Disease :
-If caused by TB , calcification is a common finding
4-Neuroblastoma
5-Granulomatous Disease
6-Pheochromocytoma
7-Myelilipoma