Adrenal

Question 1

@# 31) A 50-year-old man has surgery to remove a tumour confined to the adrenal gland. Histology reveals a phaeochromocytoma. Subsequently, he develops hypertension and urinary vanillylmandelic acid is found to be elevated. An MIBG scan is performed. Activity in which of the following organs is most likely to be a metastasis?

a. lung

b. bladder

c. thyroid

d. colon

e. spleen

Answer 1

a. lung

Normal MIBG uptake is seen in myocardium, liver, spleen, bladder, adrenal glands, salivary glands, nasopharynx,
thyroid and colon. Abnormal MIBG activity is seen in phaeochromocytoma (paraganglioma when extra-adrenal), neuroblastoma, carcinoid tumour, medullary thyroid carcinoma and ganglioneuroma. Ten per cent of phaeochromocytomas are familial, 10% bilateral or multiple, 10% extraadrenal and 10% malignant. Metastatic spread is to bone, lymph nodes, liver and lung.

Question 2

37) A man is found to have a single adrenal mass of diameter 35 mm. On an unenhanced CT scan, the average attenuation value is 30 HU. On a CT timed at 60 seconds after iodinated contrast medium injection, the attenuation value of the mass is 90 HU. By 15 minutes after contrast, the attenuation value is 50 HU. Which of the following is the most likely diagnosis?

a. lipid-rich adenoma

b. lipid-poor adenoma

c. metastasis

d. adrenal cortical cancer

e. adrenal haemorrhage

Answer 2

b. lipid-poor adenoma

An unenhanced CT attenuation value of less than 10 HU is in keeping with a lipid-rich adenoma.

With a threshold of 60% or higher for absolute contrast-enhancement washout, a sensitivity of 98% and specificity of 92% can be achieved in differentiating adenomas from non-adenomas.

Percentage of enhancement washout ¼ ([attenuation at 60 s – attenuation at 15min] / [attenuation at 60 s – attenuation on plain CT])100. Applying this to the figures quoted in the question gives an absolute washout of around 66.6%.

Question 3

(GU) 33) A 4-year-old boy presents with a mixed endocrine syndrome of precocious puberty and cushingoid
features. CT reveals a 10 cm mass replacing the left adrenal gland with cystic areas in keeping with haemorrhage and necrosis. The mass is continuous with the upper pole of the left kidney, which is expanded and has acquired the same CT appearance as the adrenal mass. No enlarged nodes or distant metastases are identified. Choose from the following the correct stage grouping:

a. I

b. II

c. III

d. IV3

e. V

Answer 3

d. IV3

The clinical and radiological findings are of adrenal cortical carcinoma, which is a disease with two age peaks, the first in early childhood (two-thirds of affected children being younger than 5 years) and the second in the fourth and fifth decades. Preliminary staging is performed with CT, though MR may be useful in evaluation of vascular or local invasion.

T1 and T2 tumours are _5 cm and >5 cm, respectively, with no evidence of invasion.

T3 tumours extend outside the adrenal into fat,

and T4 tumours invade adjacent organs.

Stage IV disease includes any ‘T’ or ‘N’ staging with metastases, T3 N1 and T4 disease. There is no stage V.

Question 4

75) A 70 year old, who is a lifelong smoker, is investigated for weight loss. Among other findings, an adrenal
nodule of 3 cm short axis diameter is found on post-contrast CT, with an average attenuation value of 60 HU. On in-phase T1W images, the adrenal nodule is isointense to spleen; on out-of-phase T1W images, the whole of the nodule returns significantly lower signal than the spleen. Of the following, which is the most likely diagnosis for this adrenal nodule?

a. lung cancer metastasis

b. collision tumour

c. adrenal adenoma

d. phaeochromocytoma

e. hyperfunctioning adrenal cortical neoplasm

Answer 4

c. adrenal adenoma

Signal dropout during out-of-phase T1W sequences occurs in lipid-rich adenomas by virtue of their fat content.

Adrenal primaries and metastases do not share this feature.

Collision tumours arise when a metastasis occurs in an adrenal gland that already contains an adenoma, in which case signal characteristics of both are seen on the T1W in- and out-of-phase sequences.

Question 5

(GIT) A 2.3 cm adrenal lesion is noted in a 62-year-old man undergoing a staging CT for colon carcinoma. A
dedicated study demonstrates the lesion to have a density of -2 H before contrast medium, 56 HU in the portal
venous phase and 20 HU at 10 minutes. What is the most likely diagnosis?

(a) Cyst

(b) Adenoma

(c) Metastasis

(d) Lipoma

(e) Adrenocortical carcinoma

Answer 5

(b) Adenoma

An adenoma is typically a low density lesion (< 15 HU) due to fat within the lesion. It usually demonstrates a
rapid wash-in and wash-out of intravenous contrast medium, thus the density at 10 minutes is less than half that
seen in the portal venous phase.

Question 6

2 Following the administration of intravenous contrast medium for an IVU, the patient becomes rapidly unwell
with hypotension, bradycardia and shortness of breath. Which of the following treatments should not be used?

(a) Oxygen delivered via a face mask

(b) Beta-2 agonist delivered via a nebuliser

(c) Adrenaline 1:1,000 0.3 mis intravenously

(d) Atropine 0.6 mg intravenously

(e) Normal saline intravenously

Answer 6

(c) Adrenaline 1:1,000 0.3 mis intravenously

Adrenaline is used in the treatment of severe contrast reactions; however the 1: 1,000 concentration should only
be given via the intramuscular route. The spectrum of contrast reactions is wide and treatments range from simple
supportive measures such as leg elevation and oxygen for mild vasovagal episodes through to adrenaline and H1
antagonists with airway support for severe anaphylactic reactions.

Question 7

8 A 22 year old woman is diagnosed with an extra-adrenal phaeochromocytoma and undergoes an 1 123 MIBG
examination as part of his staging. Which of the following organs does not usually take up MIBG?

(a) Adrenal glands

(b) Spleen

(c) Ovaries

(d) Salivary glands

(e) Myocardium

Answer 7

(c) Ovaries

In addition to the above MIBG is taken up (to a variable extent) by liver, lung, colon, stomach and thyroid. It is
uncommon to see uptake in the adrenal glands with 1 131 MIBG (<20%) but faint uptake is commonly seen with
1231-MIBG. Ovaries do not take up MIBG.

Question 8

31 A 4 year old is found to have unilateral adrenal calcification on CT. Which of the following is the least likely
cause?

(a) Adrenal cyst

(b) Neuroblastoma

(c) Ganglioneuroma

(d) Wolman disease

(e) Adrenocortical carcinoma

Answer 8

(e) Adrenocortical carcinoma

Adrenocortical carcinoma is a cause of adrenal calcification but presents in an older age group (4th -7th decade).

Question 9

32 A patient undergoes an unenhanced CT of the abdomen and suspicion of a left adrenal mass is raised. Which
of the following would not help differentiate ‘a true adrenal lesion from a structure mimicking it?

(a) Oral contrast administration to exclude a gastric diverticulum

(b) Intravenous contrast medium to ensure homogeneity of a splenunculus with the spleen

(c) Intravenous contrast medium to ensure a pancreatic tail mass is displacing the splenic vein anteriorly

(d) CT imaging with multi-planar reconstructions to ensure that the upper pole of the left kidney is not mimicking a mass

(e) MRI to ensure the upper pole of the left kidney is not the presumed mass

Answer 9

(c) Intravenous contrast medium to ensure a pancreatic tail mass is displacing the splenic vein anteriorly

The left adrenal gland lies in front of the upper pole of the left kidney and a mass within it can be confused with the upper pole itself, a gastric diverticulum, splenic lobulation, an accessory spleen or a mass in the tail of the pancreas.

Such a mass in the pancreatic tail. Would normally displace the splenic vein posteriorly rather than anteriorly as a true adrenal mass would.

Question 10

38 A 2 cm adrenal lesion is noted in a 52 year old woman undergoing a staging CT for lung carcinoma. A dedicated study demonstrates the lesion to have a density of 18 HU before contrast medium, 68 HU in the portal venous· phase and 57 HU at 10 minutes. What is the most likely diagnosis?

(a) Cyst

(b) Adenoma

(c) Metastasis

(d) Lipoma

(e) Adrenocortical carcinoma

Answer 10

(c) Metastasis

Metastases typically have a higher density (>15 HU) with less washout in the portal venous phase than an adenoma. The adrenal gland is the most common site for metastases from bronchogenic carcinoma.

Question 11

2 A 63 year old lady is discovered to have a 3 cm adenocarcinoma of the right lung. Staging CT reveals a unilateral, well-defined, round 12 mm adrenal lesion. A further CT characterization study reveals the lesion has Hounsfield value of + 20 on the unenhanced study. Enhancement is uniform, with delayed images demonstrating 65% washout of contrast medium. What is the likeliest diagnosis?

(a) Metastasis from lung carcinoma

(b) Adrenocortical adenoma

(c) Adrenal haemorrhage

(d) Adrenocortical carcinoma

(e) Adrenocortical hyperplasia

Answer 11

(b) Adrenocortical adenoma

Greater than 60% washout on delayed post contrast imaging is highly specific and sensitive for adenoma as
opposed to metastases.

Lipid poor adenomas may have a density of greater than 10 HU.

Adrenocortical carcinoma typically exhibits peripheral, nodular enhancement.

Question 12

12 A 2 month old presents with vomiting and diarrhea present from the neonatal period. On examination abdominal distension with hepatosplenomegaly is noted. CT demonstrates significantly enlarged adrenal glands which maintain their normal shape and have extensive punctuate calcification bilaterally. Small bowel wall
thickening is also noted. What is the likeliest diagnosis?

(a) Waterhouse-Friedrichsen syndrome

(b) Wolman disease

(c) Neuroblastoma

(d) Tuberculosis

(e) Phaeochromocytoma

Answer 12

(b) Wolman disease

Wolman disease is a rare autosomal recessive lipidosis with accumulation of cholesterol and triglycerides in various tissues presenting in the neonatal period with malabsorption, failure to thrive and hepatosplenomegaly.
The classic imaging finding is bilateral enlarged adrenal glands which maintain their normal shape and have extensive punctuate calcification throughout.

Question 13

15 A 16 year old boy presents with a history of headaches, abdominal pain, palpitations and sweating. CT
examination shows bilateral well defined adrenal lesions, each measuring approximately 2 cm, which enhance
avidly with intravenous contrast medium. MRI shows the lesions to be hyperintense to spleen on T2W with no
change in signal on opposed phase T1W. Angiography shows a ‘spoke-wheel’ like appearance of both lesions.
What is the likeliest diagnosis?

(a) Bilateral phaeochromocytoma

(b) Adrenocortical carcinoma with contralateral metastasis

(c) Adrenal hyperplasia

(d) Li-Fraumeni syndrome

(e) Bilateral hyperfunctioning adrenocortical adenomas

Answer 13

(a) Bilateral phaeochromocytoma

The imaging features of Phaeochromocytoma in addition to those described also include uptake of 131 1/1231-MIBG on nuclear imaging. This can be useful when a primary adrenal lesion cannot be identified on CT or MRI in the context of high clinical suspicion (e.g. Raised urinary VMA).

Phaeochromocytomas have the ‘rule of 1Os’:
10% bilateral/multiple, 10% malignant, 10% familial, and 10% extra-adrenal.

Hyperfunctioning adrenocortical adenomas tend to be unilateral with contralateral atrophy.

Li-Fraumeni syndrome resulting from the loss of the p53 tumour suppressor gene results in multiple neoplasms including adrenocortical carcinoma. These demonstrate heterogeneous contrast enhancement with a well circumscribed rim on CT.

Question 14

(General)28 Regarding the practical use of Hyoscine-N-butylbromide as a smooth muscle relaxant in imaging of the pelvis, which of the following statements is true?

(a) The dose is 2 mg given intravenously

(b) A history of angina is a contraindication

(c) It is contraindicated in patients with porphyria

(d) Open angle glaucoma is a contraindication

(e) The patient should not drive him/herself home

Answer 14

(c) It is contraindicated in patients with porphyria

Buscopan is a commonly used short acting (up to 1 hour) antimuscarinic drug. The dose is 20 mg i. v. A history of allergy should be explored. All patients should be warned that in the event of painful, blurred vision, medical attention should be sought. Stable cardiac disease is not an absolute contraindication. Porphyria and closed angle glaucoma are contraindications.

Question 15

24. In a 72 year old man undergoing abdominal CT for ongoing lower abdominal pain, a 2 cm right-sided adrenal
    lesion is detected. He has no history of malignant disease. Which of the following parameters would be more in
    keeping with a malignant than a benign adrenal lesion?

a. Size of 2.5 cm

b. Hounsfield units of 8 on non-enhanced CT

c. Washout of >60% when comparing non-enhanced CT with contrast-enhanced CT

d. Loss of signal within the lesion on out-of-phase MRI imaging

e. Maximum standardised uptake value >4 on FDG-PET

Answer 15

24. e. Maximum standardised uptake value >4 on FDG-PET

This is suspicious for metastatic malignant disease with the most common primary sites being lung, colon,
melanoma and lymphoma. An incidental adrenal lesion is detected on 1% of abdominal CT. Even in the presence
of a known malignancy, 87% of incidental lesions less than 3 cm in size are benign. Other features suggestive of
malignancy are large size, irregularity and inhomogeneity.

Question 16

29. A 40 year old female is found to have a suspected incidental left adrenal lesion on ultrasound. Which of the
    following CT or MR features is least likely in a phaeochromocytoma?

a. High signal on T2-weighted images

b. Avid enhancement post-gadolinium injection

c. Mean lesion attenuation of more than 10 HU

d. Less than 40% washout on delayed CT scanning

e. Calcification

Answer 16

29. e. Calcification

Whilst phaeochromocytomas can have varied appearances on CT and MR, typically they are high on T2-weighted and low on T1-weighted images and enhance avidly post-contrast. They normally have an attenuation value of more than 10 HU, but calcification is seen in only about 10% of cases.

Question 17

36. A middle-aged woman presenting to the medical team with headaches, palpitations, tachycardia and
    hypertension is suspected to have a phaeochromocytoma. You are asked advice on imaging modalities. Which
    one of the following statements is true regarding the imaging characteristics of a phaeochromocytoma?

a. I-131 MIBG imaging is only 20% sensitive for phaeochromocytoma

b. Poor contrast enhancement on CT

c. Bilateral in 25% of cases

d. Usually hypovascular on angiography

e. No change in signal intensity between in-phase and out-of-phase T1-weighted MRI images

Answer 17

36. e. No change in signal intensity between in-phase and out-of-phase T1-weighted MRI images

There is no change between the in-phase and out-of-phase imaging on MRI as there is very low fat content in phaeochromocytoma.

MR is the method of choice for imaging and usually (60%) the phaeochromocytoma will be hyperintense to spleen on T2-weighted imaging.

Angiography can localise the lesion in >90% of cases.

Appearance on ultrasound can be variable with about 70% appearing as solid lesions whilst 15% are cystic.

The ‘rule of tens’ applies to phaeochromocytoma, i.e. 10% are bilateral, 10% are extra-adrenal, 10% are malignant and 10% are familial.

Question 18

40. A 2 cm adrenal lesion with an attenuation value of 20 HU is seen on a non-contrast CT of a patient with lung
    cancer. The following are all true except:

a. A 60% washout on delayed post-contrast CT would be in keeping with an adenoma

b. A signal intensity decrease of 40% or more on chemical shift imaging indicates malignancy

c. PET-CT is interpreted as positive if the FDG uptake of the adrenal lesion is greater than that of the liver

d. Functioning adrenal adenomas can be a cause for false positives on PET-CT

e. PET-CT has somewhat higher and more consistent accuracy than dynamic CT or chemical shift MR imaging

Answer 18

40. b. A signal intensity decrease of 40% or more on chemical shift imaging indicates malignancy

A signal intensity decrease of less than 20% is usually indicative of malignancy in an adrenallesion.

Question 19

@# 47. An abdominal plain film of a four year old child taken for unexplained abdominal pain shows bilateral adrenal calcification as an incidental finding. Which of the following is the most common cause of adrenal calcification in children?

a. Wolman’s disease

b. Tuberculosis

c. Adrenal haemorrhage

d. Adrenal carcinoma

e. Histoplasmosis

Answer 19

47. c. Adrenal haemorrhage

All of the above cause adrenal calcification. The most common cause in both adults and children is adrenal
haemorrhage. In adults this is most commonly unilateral and rightsided. In children adrenal haemorrhage is most common in newborn infants and is induced by episodes of birth trauma or hypoxia, but may also be related to non-accidental injury.

Wolman’s disease is a rare disease causing enlarged calcified adrenal glands, hepatomegaly and splenomegaly.

Question 20

@#e QUESTION 24
A 64-year-old man presents with right renal colic and a kidney ureter bladder plain radiograph (CT KUB) is
performed. This demonstrates an incidental 2-cm solid right adrenal mass. On the unenhanced CT, the mass is
homogeneous and has an average density of 7 HU. What is the most likely diagnosis?

A Adrenal adenoma

B Adrenal hyperplasia

C Adrenal metastasis

D Focal adrenal haemorrhage

E Primary adrenal malignancy

Answer 20

A Adrenal adenoma

The 10-HU threshold is now the standard by which radiologists differentiate lipid-rich adenomas from most other
adrenal lesions on unenhanced CT. The presence of substantial amounts of intracellular fat is critical in malting
the specific diagnosis of adenoma. Up to 30% of adenomas, however, do not have abundant intracellular fat and,
thus, show attenuation values greater than 10 HU on unenhanced CT. Lesions above 10 HU on an unenhanced
CT are considered indeterminate and other investigations may be required.

Question 21

QUESTION 27
Dynamic contrast-enhanced CT may be used to characterise adrenal lesions. Which one of the following
statements best describes the imaging characteristics of a primary adrenal carcinoma on portal venous phase (70s)
and subsequent delayed phase (15 min) contrast-enhanced CT images?

A Early washout on delayed images

B No measurable enhancement in either phase

C Poor early enhancement, with an increase in enhancement on delayed images

D Washout by greater than 80%, compared with the early postcontrast

E Washout of less than 40% on delayed images, compared with the portal venous phase images

Answer 21

E Washout of less than 40% on delayed images, compared with the portal venous phase images

Malignant lesions have abnormally high vascular density leading to slower flow and’increased microvascular
permeability. This translates to longer transit times for intravenous contrast within malignant adrenal lesions,
compared with simple adenomas.

Question 22

(Ped) 23. An infant with ambiguous genitalia is referred for ultrasound of pelvis. This shows a normal
uterus and ovaries, suggesting female pseudohermaphroditism. There is elevated 17-hydroxyprogesterone. What further investigation is recommended?

A. Ultrasound of adrenal glands.

B. MRI of pelvis.

C. Fluoroscopic genitography.

D. Laparoscopy.

E. Ultrasound of inguinal region.

Answer 22

23. A. Ultrasound of adrenal glands.

Congenital adrenal hyperplasia (CAH) is the most common cause of ambiguous genitalia. It causes virilization in
females and precocious puberty in males. Most cases are caused by 21-hydroxylase deficiency resulting in
elevated 17-hydroxy-progesterone level. Enlarged adrenal glands, limbs over 20 mm in length and 4 mm width,
with nodular contour and normal cortico-medullary differentiation are suggestive of CAH. Stippled echogenicity
producing cerebriform appearance is considered specific for CAH. Normal adrenal glands do not, however,
exclude the diagnosis.

Question 23

30. A 36-year-old male patient presents with abdominal pain. He has a history of hypertension and obesity.
    A CT of abdomen reveals a 6-cm right adrenal mass, which shows heterogenous but peripheral
    enhancement, necrosis, and some calcification. There is early invasion of the IVC. The left adrenal gland
    is atrophied. What is the most likely diagnosis?

A. Neuroblastoma.

B. Adrenal cortical carcinoma.

C. Myelolipoma.

D. Adrenal adenoma.

E. Phaeochromocytoma

Answer 23

30. B. Adrenal cortical carcinoma.

The clinical picture is one of undiagnosed Cushing’s syndrome with obesity and hypertension. In this case it is adrenocorticotropic hormone (ACTH) independent Cushing’s, as the negative feedback from the cortisol
producing adrenal carcinoma causes reduction in ACTH levels and atrophy of the contra-lateral, normal adrenal gland.

Adrenal adenoma can cause Cushing’s syndrome, but the features described point to adrenal carcinoma.

They have a bimodal distribution (first and fourth decades). On average 55% are functional, manifesting with
Cushing’ syndrome, feminization, virilisation, or a mixture of these.

Hypertension is common in all syndrome types.

The majority of masses measure more than 6 cm. They are inhomogenous on unenhanced CT, owing to
necrosis. They enhance heterogeneously, often peripherally, with a thin rim of enhancing capsule in some cases.
In 19–33% of cases calcification or microcalcifications have been identified.

The liver is the most common metastatic site, followed by the lung and lymph nodes. Direct extension and tumour thrombus can also occur.

Compression of the IVC can lead to presentation with abdominal pain, lower extremity oedema or pulmonary embolism.

Neuroblastoma is a disease of childhood.

Myelolipoma is a relatively uncommon benign adrenal mass containing fat and haemopoeitic tissue.

Phaeochromocytoma is classically brightly enhancing, but can have a variety of CT appearances. It would explain hypertension, but not atrophy of the contra-lateral adrenal gland.
Phaeochromocytoma rarely invades the IVC.

Question 24

35. A 58-year-old smoker presents with haemoptysis and chest pain. A CT of chest confirms a lung
    carcinoma. While reporting the CT you notice that there is enlargement of the right adrenal gland. The
    patient has already left the department, but by chance is due to have an MRI scan of lumbar spine at a
    nearby institution the following morning. Due to time constraints, they can only fit in one sequence to image
    the adrenal glands. Which one sequence is of most use in further characterizing the adrenal abnormalities?

A. T2WI.

B. STIR.

C. Axial T1WI with fat saturation

D. In- and out-of-phase T1WI.

E. DWI.

Answer 24

35. D. In- and out-of-phase T1WI.

This is a T1WI technique and will reveal the presence of intracellular lipid via a dropout of signal on the out-ofphase imaging when compared to the in-phase imaging. Thus a benign adrenal adenoma will show such signal
dropout (20% or greater in quantity is diagnostic; 10–20% is highly suggestive), whilst adrenal metastases will
not. However, approximately 15% of benign adenomas do not accumulate intracellular lipid and may retain signal
on the out-of-phase imaging; in such cases, dynamic gadolinium-enhanced images can increase specificity to over
90–95% (by showing washout characteristics as seen on CT). If there is still doubt, PET-CT is useful. Adrenal
hyperplasia may also show loss of signal on the out-of-phase imaging. Of note an adrenal cortical carcinoma can
show dropout of signal in portions on the out-of-phase sequence, but there is not the uniform loss of signal as
seen with adenomas. The T1WI with fat saturation will show signal dropout in areas of extracellular lipid, e.g.
macroscopic fat in lipomas, dermoid cysts, or the subcutaneous tissues. T2WI is not of much benefit in
distinguishing benign from malignant adrenal masses unless the tumour is a phaeochromocytoma, which can
show very high T2WI signal

Question 25

41. A 54-year-old female patient presents with anaemia and haematuria. A CT of abdomen confirms renalcell carcinoma of the right kidney, but there is also enlargement of the right adrenal gland. Which of the
    following CT characteristics is most consistent with a benign adrenal adenoma?

A. A pre-contrast attenuation of 50.

B. An immediate post-contrast attenuation of 50.

C. A relative percentage washout (RPW) of 60%.

D. Lesion size of 50 mm.

E. Heterogeneity of the lesion.

Answer 25

41. C. A relative percentage washout (RPW) of 60%.

Findings consistent with an adrenal adenoma are: a pre-contrast attenuation of 10 HU or less, an absolute
percentage washout (APW) of 60% or greater, or an RPW of 40% or greater. The percentage washout is calculated
by comparing the attenuation value at 15 minutes post contrast (delayed H), to the value in the portal venous
phase (enhanced H), and in the case of APW, the pre-contrast value. RPW = 100 × (enhanced H – delayed
H)/enhanced H APW = 100 × (enhanced H – delayed H)/(enhanced H – pre-contrast H) In practice, an unenhanced
scan is not usually performed and thus only the RPW is calculated. Adrenal cortical carcinomas usually have an
RPW of less than 40% although exceptions have been reported. Their large size (usually greater than 6 cm),
heterogeneity pre-contrast (necrosis), and heterogeneous enhancement are more reliable indicators of the
diagnosis. Phaeochromocytomas and hypervascular metastases may mimic adenomas, but most metastases show
RPW < 40% and APW < 60%.

Question 26

6. A 64-year-old patient is referred for a CT of abdomen 10 days post laparotomy for a right
   hemicolectomy for colonic adenocarcinoma. His post-operative course is initially uneventful, but the
   request form states that over the last 2 days he has developed pyrexia and today his inflammatory markers
   are markedly raised, he is ‘septic’ and unwell. The surgeons suspect a perforation or anastomotic leak, but
   you find no significant free fluid or air. There is marked bilateral enhancement of the adrenal glands,
   which are normal in size. The remainder of the abdominal viscera are unremarkable and the IVC and
   aorta are normal in calibre. There is marked consolidation at both lung bases. What is the significance of
   the appearance of the adrenal glands?

A. Hypovolaemic shock.

B. Phaeochromocytoma.

C. Hypervascular metastases.

D. Addisonian crisis secondary to tuberculous adrenalitis.

E. Adrenal hyperplasia as a response to the recent surgery.

Answer 26

46. A. Hypovolaemic shock.

Marked adrenal enhancement may be the only sign of significant hypovolaemic shock. This is thought to be due
to hyperperfusion of the adrenal glands because of their crucial role in this clinical situation. Other signs that may
accompany this sign, the ‘hypoperfusion complex’ described in shock due to trauma, are collapsed IVC, small
hypodense spleen, small aorta and mesenteric arteries, shock nephogram (lack of renal contrast excretion), intense
pancreatic enhancement, dilatation of fluid-filled intestine with thickening of folds, and increased enhancement
of the wall. However, in cases of hypovolaemic shock due to sepsis, where there has been rapid fluid replacement,
the IVC and aorta may be of normal calibre and persisting marked adrenal enhancement has been described as
the only abnormality. Phaeochromocytomas are bilateral in only approximately 10% and this would be even less
likely in the presence of another neoplasm. Hypervascular metastases are uncommon in colonic carcinoma.
Adrenal hyperplasia may occur as a response to stress but the adrenals would enhance normally. In tuberculous
adrenalitis, the adrenal glands show areas of necrosis and sometimes calcification, with possible rim
enhancement. In all four of these alternative options the adrenal glands would be enlarged.

Question 27

1 A 50-year-old male patient undergoes a CT examination following the administration of intravenous and oral
contrast medium in the portal venous phase for investigation of persistent abdominal pain. His left adrenal gland
is noted to have a `bulky’ anterior limb width measuring 2 cm with Hounsfield units of 18. What is the most likely
diagnosis?

a Adrenal haemorrhage

b Adrenal tuberculosis

c Adrenal adenoma

d Adrenocortical carcinoma

e Adrenal myelolipoma

Answer 27

1 Answer C: Adrenal adenoma

Adrenal adenomas are common, occurring in 1-2 % of the population. On unenhanced CT examination if the
HU<10 this is 96% specific for adrenal adenoma and in the delayed phase (10-15 minutes after contrast medium)
if there is 60% washout or more then diagnosis of adenoma is 97% specific.

Question 28

2 A 45-year-old man with a spiculated mass on his chest radiograph undergoes staging CT examination following
the administration of intravenous contrast medium for a possible bronchial carcinoma. There is an enlarged right
adrenal mass of 2 cm found with an average density of 40 HU. What is the appropriate next investigation for
characterisation of the adrenal mass?

a PET

b Unenhanced and delayed phase CT examination

c MRI

d MIBG

e Follow-up staging CT examination in three months

Answer 28

2 Answer B: Unenhanced and delayed phase CT examination

Even in a patient with lung carcinoma a small adrenal mass is more likely to be an adenoma than a metastasis
(approximately 60-70%) and therefore investigation is to prove if it is an adenoma. If it is not fat containing with
washout on CT then PET examination or biopsy may need to be performed.

Question 29

3 A female neonate with a family history of an autosomal recessive lipoidosis is found to have hepatomegaly and
splenomegaly on clinical examination. Punctate cortical adrenal calcification is visible on her abdominal X-ray.
What is the most likely diagnosis?

a Neuroblastoma

b Ganglioneuroma

C Phaeochromocytoma

d Wolman’s disease

e Benign cystic disease

Answer 29

3 Answer D: Wolman’s disease

Wolman’s disease is a very rare autosomal recessive (AR) lipoidosis in which the findings described are typical.
It is almost always fatal in the first year of life.

Question 30

4 A 65-year-old female patient with a history of hypertension presents with acute right flank pain and shock. A
CT demonstrates a right-sided adrenal mass, which is of predominately low attenuation (several areas measure -
100 HU) and associated retroperitoneal haemorrhage. What is the most likely diagnosis?

a Myelolipoma

b Phaeochromocytoma

c Adenoma

d Adrenal artery aneurysm

e Adrenocortical carcinoma

Answer 30

4 Answer A: Myelolipoma

Adrenal myelolipoma are fatty-tissue masses with HU of -30 to -115. Acute retroperitoneal haemorrhage occurs
in approximately 12 %.

Question 31

5 A 38-year-old man undergoes investigation for persistent hypertension. He is found to have an increased
aldosterone and decreased renin level. What investigation is most likely to help establish the diagnosis?

a CT examination with adrenal protocol (unenhanced and delayed phases)

b MRI examination with fat suppression sequences

c MIBG

d Ultrasound

e Adrenal venous sampling

Answer 31

5 Answer A: CT examination with adrenal protocol (unenhanced and delayed phases)

Conn’s syndrome is caused by hyperaldosteronism most commonly from a hyperfunctioning adrenocortical
adenoma but also can be from bilateral adrenal hyperplasia or adrenocortical carcinoma. These adenomas can be
very small and both CT and MRI techniques have been used but CT is currently the most popular technique for
detection of adenomas.

Question 32

6 A 50-year-old female presents with sweating, palpitations and uncontrollable hypertension. As part of her workup a MIBG (metaiodobenzylguanidine) nuclear medicine scan is performed. How will this advance her
management?

a Distinguish phaeochromocytoma from carcinoid

b Locate an extra-adrenal phaeochromocytoma

c Distinguish between Cushing’s disease and Cushing’s syndrome

d Exclude papillary thyroid carcinoma

e Exclude Addison’s syndrome

Answer 32

6 Answer B: Locate an extra-adrenal phaeochromocytoma

MIBG is indicated in the investigation of phaeochromocytoma where there is clear clinical/laboratory evidence
of tumour but no adrenal abnormality on CT or MRI. MIBG is also positive for neuroblastoma, carcinoid tumour,
paraganglioma, medullary thyroid carcinoma and ganglioneuroma.

Question 33

7 A 55-year-old man with acute necrotising pancreatitis was assessed with CT after being cared for on the ITU
for six days. An unenhanced examination was performed due to renal impairment, which demonstrated bilateral
adrenal enlargement with an attenuation of 75 HU. What is the most likely cause for this?

a Adrenal adenomas

b Adrenocortical carcinoma

C Metastatic deposits

d Adrenal haemorrhage

e Adrenocortical hyperplasia

Answer 33

7 Answer D: Adrenal haemorrhage

Stress increases secretion of adrenocorticotropic hormone (ACTH), which increases adrenal vascularity and
subsequent intraglandular haemorrhage. Surgery, sepsis (Waterhouse-Friderichsen syndrome), burns,
hypotension, pregnancy, cardiovascular disease and steroids are all associated with non-traumatic adrenal
haemorrhage.

Question 34

8 A newspaper article reports that using HRT may double the risk of breast cancer. Assuming that the report
refers to the relative risk attributable to HRT and that the underlying risk in the population studied is 1.5 per 100
women over five years then what is the absolute increase in risk? (Options are per 100 women over five years.)

a 0.003

b 0.03

c 0.15

d 0.3

e 1.5

Answer 34

8 Answer E: 1.5 per 100 women over five years

The relative risk is the ratio of the absolute risk of the event occurring in those exposed to the absolute risk in
those not exposed. In this example those not exposed have an absolute risk of 1.5 and the relative risk is 2, hence
the absolute risk increase is also 1.5.

Question 35

(General) 50 A 27-year-old woman undergoing a contrast-enhanced CT pulmonary angiogram becomes
extremely agitated immediately following the examination. She complains of intense itching, periorbital tingling
and swelling, and wheeze. She has widespread urticaria, tachycardia and a blood pressure of 90/40 mmHg. Which
of the following treatments is most urgently required?
a Adrenaline (epinephrine) 1:1000 0.5 mg intravenous administration

b Hydrocortisone 200 mg intravenous administration

C 500mL 0.9% sodium chloride bolus infusion

d Adrenaline (Epinephrine) 1:1000 0.5 mg intramuscular administration

e Atropine 1 mg intravenous administration

Answer 35

50 Answer D. Adrenaline (Epinephrine) 1:1000 0.5 mg intramuscular administration

Management of acute anaphylactoid reaction: Call for help. Secure airway and administer oxygen. Elevate
patient’s legs if hypotensive. Adrenaline 1:1000 intramuscularly followed by intravenous crystalloid fluid
challenge, intravenous H, blocker and steroids.

Question 36

(Ped) 64 A 10-year-old girl with a round moon face, truncal obesity, purple abdominal striae and proximal muscle
weakness undergoes an abdominal ultrasound. Which of the following is the most likely finding?

a Multiple cysts within the left kidney

b 3-cm round hyperechoic left suprarenal mass

c 9-cm heterogeneous left suprarenal mass containing calcification

d 6-cm mixed reflectivity left suprarenal mass with a central area of low reflectivity

e 10-cm hyperechoic mass arising from the midpole of the left kidney

Answer 36

64 Answer B: 3-cm round hyperechoic left suprarenal mass

The ultrasound appearances are those of an adrenal adenoma. These are usually functional and result in the
overproduction of adrenocorticotrophic hormone or aldosterone, resulting in Cushing $ or Conn syndrome.

Question 37

2 A 78-year-old man is being investigated by the endocrinology team for chronic primary adrenal insufficiency.
As part of the endocrine investigations he undergoes CT examination of the adrenals which demonstrates small
adrenal glands with calcifications bilaterally. What is the most likely diagnosis?

a Previous tuberculosis infection

b Idiopathic adrenal atrophy

c Bilateral metastatic disease

d Ganglioneuroma

e Phaeochromocytoma

Answer 37

2 Answer A: Previous tuberculosis infection

Calcification occurs in 25% of Addison disease caused by TB. Other causes of chronic primary adrenal
insufficiency include idiopathic atrophy from an autoimmune disorder (60-70%), fungal infection
(histoplasmosis, blastomycosis, coccidioidomycosis), sarcoid and rarely bilateral metastatic disease. Both
ganglioneuroma and phaeochromocytoma can have calcifications but would be present with an adrenal mass.

Question 38

3 A 45-year-old female with a previous diagnosis of medullary thyroid cancer and hyperparathyroidism had an
abdominal MRI which demonstrated an adrenal lesion. Which of the following are the most likely radiological
findings?

a Hyperintense areas to liver on T1-weighted images and intermediate intensity to spleen on T2-weighted images

b Isointense/hypointense to liver on T1-weighted images and very hyperintense to spleen in T2-weighted images

c Heterogeneously hyperintense to liver on Ti- and T2-weighted images (ACC)

d Isointense on T1-weighted images and very hypointense on T2 -weighted images

e Hypointense on Ti- and T2-weighted images

Answer 38

3 Answer B: Isointense/hypointense to liver on T1-weighted images and very hyperintense to spleen in T2-weighted images

Phaeochromocytoma occur in 50% of patients with MEN (multiple endocrine neoplasia) type 2 and these are the
typical signal characteristics for a phaeochromocytoma. They are very high signal on T2 -weighted images
compared to spleen in 60% due to intratumoral cystic areas. They may also contain areas of high signal on T1-
weighted images in 20% due to haemorrhage, but in comparison to myelolipoma and adenomas, which contain
fat, there is no change in signal intensity between in and out of phase images in phaeochromocytoma. Option (a)
is the signal characteristics of a myelolipoma and option (c) of adrenal cortical carcinoma. Options (d) and (e) are
adrenal haemorrhage signal characteristics at different stages of evolution.

Question 39

4 On abdominal CT examination, which of the following appearances of the adrenal gland is unexpected and
would require further evaluation?

a Length of the adrenal limb measures 4 cm

b Width of the adrenal limb measures 2 cm

c Right adrenal lying behind the IVC

d Left adrenal lying in front of the upper pole of left kidney

e Right adrenal not seen on the same CT slice as the right kidney

Answer 39

4 Answer B: Width of the adrenal limb measures 2 cm

The normal width of an adrenal gland is less than 1 cm.

Question 40

5 A nine-year-old boy presents to the endocrinology team with bilateral testicular masses and precocious puberty.
Which of the following are the most likely radiological findings?

a Bilateral diffuse enlargement of the adrenals but preservation of their usual morphology

b Normal size and appearance of the adrenals

c Bilateral global atrophy of the adrenals but preservation of their usual configuration

d Lack of normal adrenal tissue bilaterally

e Unilateral enlarged adrenal with preservation of usual configuration

Answer 40

5 Answer A: Bilateral diffuse enlargement of the adrenals but preservation of their usual morphology

Congenital adrenal hyperplasia is a group of autosomal recessive conditions due to defective enzyme synthesis,
which ultimately produces increased ACTH and hyperplasia of the adrenal cortex. As well as adrenal hyperplasia
there is also hyperplasia of rest tissue, which is seen in the retroperitoneum and testes.

Question 41

8 A 60-year-old female patient undergoes a CT examination and is incidentally found to have a heterogeneous
left adrenal mass measuring 12 cm, which contains calcifications and has delayed washout characteristics.
Biochemical endocrine testing is negative. What other condition is associated with the most likely diagnosis?

a Astrocytoma

b Multiple endocrine neoplasia (MEN) Type 1

C Multiple endocrine neoplasia (MEN) Type 2A

d Carney complex

e Neurofibromatosis

Answer 41

8 Answer A: Astrocytoma

The patient is asymptomatic, negative endocrine testing and has a large mass with delayed washout, which are
all consistent with a diagnosis of adrenal cortical carcinoma (ACC). Of these, 30% are calcified and the
calcifications and large size are suggestive of malignancy. ACC is associated with hemihypertrophy, BeckwithWiedemann syndrome and astrocytomas. Phaeochromocytoma is associated with MEN2 and neurofibromatosis.
Adrenocortical hyperplasia is associated with the Carney complex; phaeochromocytoma is associated with the
Carney syndrome.

Question 42

1 A neonate of a diabetic mother is born following a difficult labour via forceps delivery. An ultrasound
examination performed in the first week demonstrated a right-sided complex solid echogenic mass in the region
of the right adrenal. The remainder of the abdominal ultrasound examination was unremarkable. What is the most
likely diagnosis?

a Non-hyperfunctioning adrenocortical adenoma

b Hyperfunctioning adrenocortical adenoma

c Traumatic adrenal haemorrhage

d Non-traumatic adrenal haemorrhage

e Adrenocortical hyperplasia

Answer 42

1 Answer D: Non-traumatic adrenal haemorrhage

Neonatal stress can cause non-traumatic adrenal haemorrhage, which is the most common neonatal lesion of the
adrenal gland. Infants who are large for gestational age and those of diabetic mothers are predisposed. It occurs
R:L = 7:3 and is bilateral in 10%.

Question 43

2 A 45-year-old patient underwent CT and is incidentally found to have an adrenal mass. What additional finding
would suggest a diagnosis of phaeochromocytoma rather than adrenal adenoma?

a Calcification

b Size <2 cm

c Attenuation>30HU

d Arterial phase enhancement

e Homogeneous enhancement

Answer 43

2 Answer C: Attenuation >30HU

Although phaeochromocytoma may contain intracellular fat (and therefore appear hyperintense on T1- weighted
MR images) they are of increased attenuation relative to fat-containing adenomas on CT. Calcification can be
present in both as can arterial phase enhancement. Phaeochromocytoma tend to be >3 cm and often appear
heterogeneous.

Question 44

3 A 41-year-old patient undergoes CT examination and is found to have an incidental adrenal mass. What
additional finding would suggest a diagnosis of myelolipoma rather than an adrenal adenoma?

a Presence of large amount of mature fat

b HU<10 on unenhanced CT

c Calcification

d Unilateral

e Size >5 cm

Answer 44

3 Answer A: Presence of large amount of mature fat

Adrenal myelolipomas contain a large amount of mature fat, causing their attenuation to be -30 to -115HU. Lipidrich adenomas will also have a HU<10 but contain intracytoplasmic lipid and are of higher attenuation. The mean
size of an adrenal adenoma is approximately 2 cm, but the mean diameter of a myelolipoma is approximately 10
cm. Calcification can occur in both.

Question 45

4 A 40-year-old woman with paroxysmal hypertension was diagnosed with a phaeochromocytoma of her left
adrenal. As part of the work-up a mass on her right adrenal was also discovered that was of a similar appearance
on CT. An MRI was then performed. What feature would favour lesion being an incidental adrenal adenoma?

a Heterogeneous enhancement

b Slow washout following enhancement

c Extremely high signal on T2-weighted images

d India ink effect on chemical shift MRI

e Low signal on T1-weighted images on MRI

Answer 45

4 Answer D: India ink effect on chemical shift MRI

The presence of lipid causes the characteristic black lines outlining the interface between organ and adjacent fat
and as phaeochromocytoma do not contain fat would be suggestive of an adenoma. Marked hyperintensity on T2
images is typical of a phaeochromocytoma. Similarly, heterogeneous enhancement and slow washout are more
suggestive of phaeochromocytoma than adenoma

Question 46

5 A 62-year-old patient presented with a cough and a CXR showed a possible mass in the left lung. He then
underwent further evaluation with contrastenhanced CT. This confirmed the presence of a pulmonary mass but
also showed an adrenal mass. What additional finding would suggest a diagnosis of adrenal adenoma rather than
an adrenal metastasis?

a Calcification

b Attenuation of 50 HU on portal venous phase images

c Attenuation of 26 HU on delayed images 15 minutes after contrast injection

d Contralateral gland atrophic

e 1-cm low-density lesion on contralateral adrenal

Answer 46

5 Answer C: Attenuation of 26 HU on delayed images 15 minutes after contrast injection

Attenuation of <37HU on delayed images has been suggested to be diagnostic of adenoma.

Question 47

6 A 43-year-old man has had a diagnosis of phaeochromocytoma given by the endocrine team. Which of the
following tests would be dangerous due to risk of precipitating life-threatening hypertension? (He is not on alphaor beta-blocking drugs)
a Contrast-enhanced CT with non-ionic intravenous contrast medium

b MIBG scan

c Abdominal MRI scan with gadolinium

d CT-guided core biopsy

e FDG-PET scan

Answer 47

6 Answer D: CT-guided core biopsy

Biopsy of phaeochromocytoma, which is catecholamine producing, may precipitate life-threatening hypertension
or arrhythmia. Non-ionic intravenous contrast medium can safely be used for CT examination without alphaadrenergic blockade. 6 Answer D: CT-guided core biopsy Biopsy of phaeochromocytoma, which is
catecholamine producing, may precipitate life-threatening hypertension or arrhythmia. Non-ionic intravenous
contrast medium can safely be used for CT examination without alpha-adrenergic blockade.

Question 48

7 A 67-year-old woman with metastatic breast carcinoma is noted to have adrenal metastases that are of increased
uptake on a PET examination. In which part of the adrenal do these characteristically occur?

a Outer adrenal cortex

b Medulla

c inner adrenal cortex

d Corticomedullary junction

e Adrenal capsule

Answer 48

7 Answer D: Corticomedullary junction

Question 49

8 A 50-year-old female patient undergoes CT examination and is found to have an incidental adrenal lesion. This
area is cystic in appearance and measures 4 cm. The wall is thin at 2 mm and the contents are homogeneous with
almost water attenuation. There is no enhancement following the administration of intravenous contrast medium.
What is the most likely diagnosis?

a Cystic phaeochromocytoma

b Cystic adrenocortical carcinoma

c Adrenal adenoma

d True adrenal cyst

e Lymphangioma

Answer 49

8 Answer E: Lymphangioma

True adrenal cysts are rare. Endothelial lining `cysts’ such as lymphangioma are more common. Pseudocysts also
occur from previous haemorrhage/infarction.

Question 50

(Ped) 16 A six-year-old girl is investigated for having pubic and axillary hair. She undergoes an abdominal
ultrasound as part of her work-up. This shows a 2 -cm well-circumscribed mass arising from the left adrenal
gland. It is hypoechoic to the kidney and does not contain any calcification. Which of the following is the most
likely diagnosis?

a Phaeochromocytoma

b Neuroblastoma

C Adrenal haemorrhage

d Adrenocortical carcinoma

e Adrenal metastasis

Answer 50

16 Answer D: Adrenocortical carcinoma

These are rare in children, with an incidence of 3:1000 000. They present with a palpable abdominal mass
and/or virilisation in females and precocious puberty in males. Approximately 20% contain calcification.

Question 51

16. A 52-year-old male smoker has been recently diagnosed with bronchogenic carcinoma with cerebral
    metastasis. Staging CT shows a 1.5 cm nodule in the left adrenal gland. On MRI, the nodule is isointense to spleen
    on T2 and shows marked hypointensity on out-of-phase GRE images. What is the most likely diagnosis?

(a) Adrenal metastasis

(b) Adrenal adenoma

(c) Adrenocortical carcinoma

(d) Adrenocortical hyperplasia

(e) Adrenal cyst

Answer 51

16. (b) Adrenal adenoma

This is the typical feature of adrenal adenoma and is seen in more than 95% adenomas. The fat/lipid in the
adenoma causes a chemical shift artefact which results in signifcant loss of signal on out-of-phase GRE images.

Question 52

27. A 57-year-old hypertensive woman presents with recurrent abdominal pain. Urine shows elevated levels of
    vanillylmandelic acid. CT shows a large mass at the superior pole of right kidney. On MRI, the lesion is
    heterogenous, and appears low signal on T1 and high signal on T2 with enhancement with gadolinium. What is
    the most likely diagnosis?

(a) Lymphoma

(b) Renal cell carcinoma

(c) Pheochromocytoma

(d) Retroperitoneal liposarcoma

(e) Nodal metastasis

Answer 52

27. (c) Pheochromocytoma

This tumour usually arises from the adrenal medulla. Note the 10% rule: 10% are extra-adrenal, 10% malignant
and 10% bilateral. MRI features are typical and with elevated urine vanillylmandelic acid levels it is diagnostic.

Question 53

32. A 45-year-old man presents with left-sided pain in abdomen. CT shows a 5 cm mass in the left adrenal gland,
    predominantly containing tissues with Hounsfeld units of approximately -80. On MRI, the lesion high signal on
    T1 and low signal on STIR sequence. What is the most likely diagnosis?

(a) Liposarcoma

(b) Adrenal myelolipoma

(c) Adrenal carcinoma

(d) Adrenal metastases

(e) Pheochromocytoma

Answer 53

32. (b) Adrenal myelolipoma

Given the negative Hounsfeld units on CT and loss of signal on fat suppression, the lesion contains predominantly
fat. These are benign tumours containing fat and haematopoietic tissue. Presence of fat in an adrenal lesion is
highly suggestive of a myelolipoma.

Question 54

24. Which of the following are correct regarding pheochromocytoma: (T/F)

(a) Is associated with gastric haemorrhage.

(b) Affects the bladder.

(c) Is bilateral in 20-40% of cases.

(d) Is extra-adrenal in 20-30% of cases.

(e) Is associated with tuberous sclerosis.

Answer 54

Answers:

(a) Correct
(b) Correct
(c) Not correct
(d) Not correct
(e) Correct

Explanation:

The pheochromocytoma follows 10% rule. It is bilateral in 10% cases, 10% cases are extra adrenal, 10% are
malignant, 10% are in children, 10% are familial, 10% are not associated with hypertension and 10% show
calcification

Question 55

30. Which of the following are correct regarding pheochromocytoma: (T/F)

(a) Is bilateral in 25%

(b) When symptomatic tends to be large at presentation.

(c) Is associated with pulmonary hamartomas.

(d) Usually has CT attenuation values of <10 Hounsfield units (HU) on unenhanced scans.

(e) Is of high signal intensity on T2 weighted MR.

Answer 55

Answers:

(a) Not correct
(b) Not correct
(c) Correct
(d) Not correct
(e) Correct

Explanation:

Pheochromocytoma are bilateral in 10% cases, and symptomatic lesions tend to be smaller in size.
They rarely contain enough fat to reduce the attenuation value <10 HU units.

Question 56

@#e 31. Which of the following are correct regarding benign and malignant adrenal masses: (T/F)

(a) Chemical shift MR utilises T1 weighted sequences.

(b) Approximately one third of benign adenomas have HU of >10 on unenhanced CT.

(c) Adenomas tend to show delayed enhancement with IV contrast.

(d) Adenomas tend to show delayed clearance of IV contrast.

(e) Lesions >4cm tend to be malignant.

Answer 56

Answers:

(a) Correct
(b) Correct
(c) Not correct
(d) Not correct
(e) Correct

Explanation:

Adenomas (benign) show rapid enhancement and rapid washout of contrast media on post contrast study.