Vascular

Question 1

3) A 32-year-old female presents with shortness of breath and hemoptysis. There is no leg swelling and an ECG is normal. A chest radiograph shows a triangular, plurally based opacity in the right mid-zone with an ipsilateral effusion. Which investigation would be most helpful in making the diagnosis?

a. V =Q scan

b. CT pulmonary angiogram

c. conventional pulmonary angiogram

d. high-resolution CT

e. staging CTof chest

Answer 1

b. CT pulmonary angiogram

The differential diagnosis is between pulmonary embolus or pneumonia with effusion, with investigation directed accordingly. High-resolution CT would be unhelpful with lack of contrast. A staging chest CT is performed in the aortic phase of contrast so pulmonary arteries will be sub optimally seen. CT pulmonary angiogram is the best investigation in this case, because, when there is consolidation/ opacification present on a chest radiograph, a _V =_Q scan has a high likelihood of being no diagnostic. Conventional pulmonary angiography is a high-risk procedure and is rarely performed in modern practice.

Question 2

4) A 56-year-old female patient presents with shortness of breath. A chest radiograph is unremarkable. A highresolution CT scan is performed which shows mosaic perfusion with no air trapping on expiratory scan. What is the most likely diagnosis?

a. bronchiolitis obliterans

b. cystic fibrosis

c. hypersensitivity pneumonitis

d. chronic thromboembolic disease

e. asthma

Answer 2

d. chronic thromboembolic disease

Mosaic perfusion is caused by abnormalities of ventilation, or vascular obstruction. Expiratory scans help to distinguish causes by establishing whether there is air trapping. With no air trapping present, pulmonary emboli of any cause are most likely. Air trapping would suggest airway disease such as bronchiolitis obliterans, or other causes of small airway obstruction such as bronchiectasis or cystic fibrosis.

Question 3

22) A 25-year-old male presents with recurrent epistaxis, which is progressively worsening. On examination, he is noted to have multiple, red, vascular skin blemishes. A chest radiograph shows several opacities in the lung measuring up to 3 cm with bands of opacification extending to the hila. No calcification is seen. What is the most likely diagnosis?

a. hereditary hemorrhagic telangiectasia

b. neurofibromatosis

c. tuberous sclerosis

d. Wegener’s granulomatosis

e. sarcoidosis

Answer 3

a. hereditary hemorrhagic telangiectasia

hemorrhagic telangiectasia (HHT), or Rendu–Osler–Weber syndrome, is a disorder that produces telangiectasia, arteriovenous malformations (AVMs) and aneurysms, affecting multiple organ systems. Recurrent epistaxis is seen in up to 85% of cases. Up to 15% of patients with HHT have multiple pulmonary AVMs, and 60% of patients with pulmonary AVMs have HHT. Wegener’s granulomatosis is also associated with epistaxis, due to granulomas of the nasal septum, but pulmonary findings are of multiple granulomas

Question 4

34) In ventilation–perfusion scintigraphy, which of the following is suggestive of an intermediate probability of pulmonary embolism?

a. matched non-segmental defects with a normal chest radiograph

b. multiple unmatched small perfusion defects with normal ventilation

c. large, segmental, matched defect with similar-sized opacity on chest radiograph

d. reverse mismatch

e. two large, unmatched, segmental, perfusion defects

Answer 4

c. large, segmental, matched defect with similar-sized opacity on chest radiograph

With ventilation–perfusion scintigraphy, matched segmental defects are considered low probability.

When there is a similar-sized area of opacification on the chest radiograph, which indicates ‘triple match’, this becomes intermediate probability.

Matched non-segmental defects, reverse mismatch and multiple small perfusion defects are all indicators of low probability.

Two large segmental perfusion defects that are not matched are considered high probability

Question 5

40. A young girl with known sickle cell disease presents with chest pain, fever, leucocytosis and hypoxia. Which of the following statements is most appropriate?

A. Consolidation is found more commonly than groundglass opacification on HRCT

B. Ground-glass change typically has a lobar distribution

C. The lower lobes are more frequently affected in adults

D. Infarction results in linear scarring

E. There is a correlation between severity of a chest crisis and extent of radiological findings

Answer 5

D. Infarction results in linear scarring

HRCT often reveals ground-glass opacification, which does not have a lobar distribution and may have a scattered or mosaic pattern. Adults tend to have lower lobe or multilobar involvement, compared to the upper lobe pattern more often seen in children. Microvascular occlusion causes a reduction in the vascular markings and infarction results in linear scarring

Question 6

41. Which of the following favours Hughes-Stovin syndrome rather than Behçet’s syndrome?

A. Diffuse airspace nodularity

B. Pulmonary consolidation

C. Pulmonary artery aneurysm

D. A lack of oral/genital ulcers

E. Mosaic perfusion on CT

Answer 6

D. A lack of oral/genital ulcers

Hughes-Stovin syndrome, also known as incomplete Behçet’s disease, overlaps in radiologic and histopathologic findings, but there is an absence of oral and genital ulcerations.

Question 7

48) A 42-year-old female patient presents with dyspnea and pleuritic chest pain. She has previously had pulmonary emboli diagnosed. A CT pulmonary angiogram is performed. Which feature would indicate chronic rather than acute thrombus on the CT?

a. complete occlusion of segmental vessel

b. filling defects centrally with peripheral contrast enhancement

c. peripheral mural filling defect forming acute angle with wall

d. peripheral mural filling defect forming obtuse angle with wall

e. linear atelectasis

Answer 7

d. peripheral mural filling defect forming obtuse angle with wall

The differentiation of acute from chronic thromboembolic disease can be difficult. Secondary changes may be present, such as hypertrophy of the right atrium and ventricle with cardiomegaly as well as pulmonary hypertension. Chronic emboli usually form peripheral flattened defects, forming obtuse angles with the arterial wall. Complete vessel occlusion may be seen in both acute and chronic emboli. The presence of recanalization or collateral formation is also suggestive of chronicity. In addition, calcification of the clot may occur, which also indicates chronicity. Parenchymal abnormalities such as atelectasis and wedgeshaped opacities may be seen in both acute and chronic pulmonary emboli.

Question 8

2- A 54-year-old woman with a 20 pack per year smoking history presents with worsening chronic dyspnea. CXR shows prominence of the central pulmonary vasculature. Contrast enhanced CT is performed. Which of the following features would not support a diagnosis of pulmonary arterial hypertension?

(a) The patient’s demographics

(b) Mosaic attenuation of the lung parenchyma

(c) Bowing of the interventricular septum convex to the right

(d) Pruning of peripheral pulmonary arteries

(e) Bronchial arteries measuring up to 4 mm in diameter

Answer 8

(c) Bowing of the interventricular septum convex to the right

There are multiple causes of pulmonary arterial hypertension which can broadly be divided into vascular, lung and cardiac causes along with idiopathic PAH. Signs include enlargement of the main PA (greater than 2.9 cm), a PA to corresponding aorta ratio of > 1 and signs of right ventricular strain which would eventually cause bowing of the interventricular system convex to the left

Question 9

4- A 25-year-old presents with an acute seizure- CT shows a 2-cm ring enhancing lesion in the frontal lobe with surrounding edema- CXR 3 opacities measuring between 1—3 cm in size, projected over the left lower zoneContrast enhanced CT shows these lesions to be round, well defined and containing linear structures radiating away from the lesions- What is the likeliest diagnosis?

(a) Lymphangioeiomyomatosis

(b) Takayasu’s arteritis

(c) Sarcoidosis

(d) Osler-Weber-Renudu syndrome

(e) Wegener’s granulomatosis

Answer 9

(d) Osler-Weber-Renudu syndrome

Also known as hereditary hemorrhagic telangiectasia, it is a group of inherited disorders that result in a number of systemic fibrovascular disorders affecting mucus membranes, skin, brain and lung. “It is associated with the presence of multiple pulmonary arterio-venous fistulae. These can act as a right to left shunt and embolic sequelae in the brain can be the presenting symptom.

Question 10

22- Regarding CT PA for the investigation of pulmonary emboli. Which of the is not a cause of a false-positive CT PA result?

(a) Hilar lymphadenopathy

(b) Low signal-to-noise ratio

(c) Narrow windowing

(d) Respiratory artefact

(e) SVC obstruction

Answer 10

(c) Narrow windowing

If a technically adequate study is performed CT PA is > 90% sensitive and specific for large, central PEs.

Falsepositive results may occur if there is increased noise (hence reduced SNR), particularly in larger patients or if patients are too unwell to lift their arms above their head.

Others include SVC obstruction (due to partial opacification of the vessels), hyperdynamic circulation, lymphadenopathy, and respiration/ motion (due to partial voluming).

Narrow windowing produces ‘brighter’ contrast thus filling defects may be obscured, resulting in a false negative result. Emboli can be detected within the proximal arteries of 5th/6th generation, sub-segmental emboli are usually undetectable (thus effectively produce a false negative result).

Question 11

2 A 35 year old Japanese man with a long history of mouth ulceration and a recent diagnosis of posterior uveitis presents to the emergency department with breathlessness. A CTPA is performed which demonstrates bilateral pulmonary emboli. What is the most likely diagnosis?

(a) Sarcoidosis

(b) Systemic Lupus Erythematosus

(c) Behcet’s disease

(d) Polyarteritis nodosa

(e) Amyloidosis

Answer 11

(c) Behcet’s disease

Behcet’s disease is an autoimmune condition that is characterised by oro-genital ulceration and uveitis. There are numerous systemic complications which include vasculitis, arterial and venous thrombosis, pulmonary artery aneurysms and pulmonary haemorrhage

Question 12

@# 13 Which of the following drugs used in treating patients with haematological malignancy is not associated with pulmonary haemorrhage?

(a) Bleomycin

(b) Cytarabine

(c) Amphotericin B

(d) Rituximab

(e) Cyclophosphamide

Answer 12

(a) Bleomycin

Bleomycin may result in one of two conditions: an organising pneumonia with multiple foci of consolidation or tree-in-bud opacification, or diffuse alveolar damage which gives appearances akin to ARDS.

Question 13

16 Which of the following CT signs is the most specific for a diagnosis of pulmonary hypertension?

(a) Aorta:pulmonary artery ratio > 1.0

(b) Main pulmonary artery diameter ~ 2.9 cm

(c) Mosaic perfusion pattern

(d) Reflux of contrast into IVC

(e) Segmental artery:bronchus ratio > 1.0 in ~ 3 lobes

Answer 13

(b) Main pulmonary artery diameter ~ 2.9 cm

There is a good correlation between a main PA ~2.9 cm and right heart catheter studies in demonstrating PHT. Some argue that the PA diameter is affected by body habitus, thus the ratio of aorta to main PA is more specific (note this is a PA : aorta ratio > 1 ). Segmental artery: bronchus ratio >1 in 3 of 4 lobes (RUL, RLL, LUL and LLL) has been used by some authors, however, this ratio may exceed 1 in normal individuals and, rarely, a ratio of ~1.25 can be within normal limits. Mosaic perfusion is indicated of small vessel disease which can lead to PHT but is not specific, and reflux of contrast into the IVC is indicative of tricuspid regurgitation which may be secondary to PHT, but is not specific. A combination of 2 or more features greatly increases specificity.

Question 14

30 A 24 year old lady, 27 weeks pregnant, presents with chest pain and you are contacted for imaging advice. Which of the following is not a risk factor/ indicator of pulmonary embolism?

(a) Raised D-dimer

(b) Gestational diabetes

(c) Thrombophilia

(d) Obesity

(e) Multiparity

Answer 14

(a) Raised D-dimer

In addition, increasing age, prolonged bed rest, familial disposition, previous venous thromboembolism, varicose veins and smoking are all risk factors. D-dimer is often elevated in pregnancy and the test is not indicated-in this situation.

Question 15

@# 32 Plain radiographic signs seen more commonly in patients with acute pulmonary embolism include all but which of the following?

(a) Cardiomegaly

(b) Decreased vascularity

(c) Pulmonary oedema

(d) Pleural opacity

(e) Atelectasis

Answer 15

(c) Pulmonary oedema

Pulmonary oedema is seen in patients with PE rarely (4% vs 13% in patients without PE). Other signs include pleural effusion.

Question 16

@# 62 A 72 year old woman with a history of recent surgery presents with shortness of breath and pleuritic chest pain. On examination there is a slight swelling of the right leg compared to the left. The D-dimer level is raised. Which imaging investigation should be performed next?

(a) Chest X-ray

(b) CTPA

(c) Pulmonary angiogram

(d) Ultrasound bilateral lower leg veins

(e) V/Q scan

Answer 16

(a) Chest X-ray

The patient is at high risk for a PE. The CXR is less likely to be diagnostic, but may provide a differential diagnosis in some cases (e.g. spontaneous pneumothorax) and forms an important part of the diagnostic flow chart.

A normal CXR means a V/Q scan would be the next appropriate investigation, abnormal CXR requires CTPA.

The right leg swelling may be post-operative rather than due to a DVT, but regardless, it is important to diagnose a PE over a DVT as most clinicians recommend a longer treatment period for the former.

Pulmonary angiography is invasive and is now rarely used in the context of PE diagnosis.

Question 17

20. The diagnostic role of CT in patients with pulmonary emboli is well established, but a prognostic role is being proposed as well. Which of the following has the most widely accepted prognostic value?

a. PA clot burden score

b. Leftward bowing of the intraventricular septum

c. Reflux of contrast into the IVC

d. RV/LV diameter ratio

e. PA diameter measurement

Answer 17

20. d. RV/LV diameter ratio.

Question 18

@# QUESTION 6 A 70-year-old man recently underwent a laparoscopic prostatectomy. He now presents to the Emergency Department complaining of shortness of breath, pleuritic chest pain and haemoptysis. D-dimer levels were measured and found to be significantly elevated. A CXR is performed as part of the initial set of investigations. Which one of the following is the most likely CXR finding?

A A normal chest radiograph

B Linear atelectasis

C Localised peripheral oligaemia

D Peripheral airspace opacification

E Pleural effusion

Answer 18

A normal chest radiograph

A normal chest radiograph is the most common finding in the setting of a suspected pulmonary embolus (PE).

Question 19

2. A previously well 42-year-old man is admitted with acute left-sided pleuritic chest pain. His SaO2 is recorded as 92%. D-Dimer assay is elevated. His mother had died suddenly at the age of 58 years. He is further investigated via CTPA, which is negative for PE. Based on his presenting symptoms, the referring consultant continues to be concerned that the patient has a PE. What advice do you offer regarding this patient’s management?

A. Refer for V/Q scanning.

B. Refer for catheter pulmonary angiography.

C. Commence anticoagulation for 3 months given clinical suspicion.

D. Commence anticoagulation for 6 months given clinical suspicion.

E. No further investigation or anticoagulation required.

F. Repeat CTPA.

Answer 19

2. E. No further investigation or anticoagulation required.

In the setting of a low probability clinical assessment and positive D-dimer assay, a negative CTPA has a negative predictive value of 96% and further investigation and treatment are therefore not warranted. A repeat CTPA may be indicated if the images are of poor quality.

The Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) II investigators recommend that in the setting of a high pre-test probability, a negative CTPA should be followed with either venous ultrasound or MR venography.

Question 20

10. A 56-year-old man is admitted via the accident and emergency (A&E) department. He has a past medical history of mitral valve disease. He is complaining of shortness of breath and the clinical team believe he has pulmonary oedema, but ask for your opinion on his CXR to rule out infection. The presence of which of the follow features could not be attributed to cardiac failure and would make you doubt the diagnosis?

A. Perihilar alveolar opacities.

B. Sparing of the lung periphery.

C. A unilateral pleural effusion.

D. Unilateral regional oligaemia.

E. Right upper lobe opacification.

Answer 20

10. D. Unilateral regional oligaemia.

This represents Westermark’s sign and is associated with PE, not pulmonary oedema. The other features are consistent with cardiac failure. In particular, focal right upper lobe oedema is associated with mitral regurgitation, where the regurgitant jet produces locally increased pressures in the right upper lobe pulmonary veins with a focal increase in oedema in that region. This can mimic consolidation on plain film, but will be seen to resolve after diuresis. Pleural effusions may be unilateral in cardiac failure.

Question 21

11. A 62-year-old man undergoes lung scintigraphy for investigation of PE. There is no prior history of PE. Which of the following scan patterns would be in keeping with a low probability for PE?

A. Triple matched defect in the lower lung zone.

B. Single moderate matched V/Q defect with a normal CXR.

C. Perfusion defect with a rim of surrounding normally perfused lung.

D. No defects present on perfusion scan.

E. Four moderate segmental defects.

Answer 21

11. C. Perfusion defect with a rim of surrounding normally perfused lung.

Multiple bilateral perfusion defects with a normal ventilation scan are the classic diagnostic findings in PE.

Occluding pulmonary emboli produce segmental perfusion defects that extend to the pleural surface. As other conditions may also produce perfusion defects, the ventilation scan improves specificity.

Non-embolic lung disease will typically have both perfusion and ventilation abnormalities, resulting in matched defects. V/Q scans are categorized as normal, low, intermediate, or high probability.

A perfusion defect that matches ventilation and CXR abnormalities in size and location is a triple matched defect. A triple matched defect in the middle or upper lung zones is in keeping with low probability, but rises to intermediate probability when in the lower zones.

A single moderate matched V/Q defect, but with a normal CXR, is also ofintermediate probability.

No perfusion defect is in keeping with a normal scan

and four moderate segmental defects is a high probability scan.

A perfusion defect with a rim of surrounding normally perfused lung is known as the stripe sign and corresponds to low probability for PE, as PE perfusion defects should extend to the pleural surface and have no overlying stripe of perfused lung.

Question 22

16. A 50-year-old woman presents with progressive exertional dyspnoea, fatigue and atypical chest pain. Her jugular venous pressure (JVP) is elevated on examination. Her CXR reveals prominence of the right side of the heart with asymmetric enlargement of the central pulmonary arteries. Patchy oligaemic vascularity is also evident. What is the most likely diagnosis?

A. Atrial septal defect.

B. Primary pulmonary hypertension.

C. Chronic thromboembolic pulmonary hypertension.

D. Cardiopulmonary schistosomiasis.

E. Pulmonary veno-occlusive disease.

Answer 22

16. C. Chronic thromboembolic pulmonary hypertension.

Pulmonary hypertension is the haemodynamic consequence of vascular changes within the precapillary (arterial) or postcapillary (venous) pulmonary circulation.

The diagnosis of primary (idiopathic) pulmonary hypertension (PPH) can only be made after exclusion of known secondary causes.

The classical findings in advanced disease include prominent central pulmonary arteries with sharply tapering peripheral vessels and right ventricular enlargement.

It typically affects younger women of childbearing age.

The radiographic features of pulmonary hypertension caused by chronic shunting are similar to PPH, although a normal sized cardiac silhouette may reflect diminished shunting due to a markedly elevated pulmonary vascular resistance.

Most congenital cardiac lesions that may eventually cause pulmonary hypertension are now repaired at an early age.

Chronic thromboembolic pulmonary hypertension may mimic PPH clinically, making diagnosis difficult. Radiographic findings are more likely to be asymmetrical. A triangular opacity representing pulmonary infarction may also been seen.

Schistosomiasis will demonstrate the radiographic features of pulmonary hypertension and may also exhibit tiny nodular granulomas.It is endemic in the Middle East, Africa, and the Atlantic coast of South America.

Pulmonary veno-occlusive disease is the post-capillary counterpart of PPH. It is suggested radiographically when the features of pulmonary arterial hypertension are accompanied by evidence of diffuse pulmonary oedema and a normal sized left atrium.

Question 23

21. A 34-year-old woman with a preceding history of chronic cough, weight loss and intermittent chest tightness presents with acute shortness of breath. CTPA reveals a large filling defect within the left pulmonary artery. Which radiological feature would most suggest a diagnosis of pulmonary artery sarcoma as opposed to pulmonary embolism?

A. Mosaic lung perfusion.

B. Peripheral filling defect forming acute angle with arterial wall.

C. Peripheral filling defect forming obtuse angle with arterial wall.

D. Low attenuation filling defect occupying and expanding the entire luminal diameter.

E. Partial filling defect surrounded by areas of intravascular contrast enhancement.

Answer 23

21. D. Low attenuation filling defect occupying and expanding the whole luminal diameter.

Pulmonary artery sarcoma is a rare malignancy arising from the intima of the pulmonary artery. It is frequently misdiagnosed as PE, although there are features that help differentiation. Findings that favour pulmonary artery sarcoma include a low attenuation filling defect occupying the entire luminal diameter of the proximal or main pulmonary artery, expansion of the involved arteries and extraluminal tumour extension. A filling defect forming an acute angle with the arterial wall is seen in acute PE, whereas a filling defect forming an obtuse angle indicates organizing thrombus in chronic PE. A partial filling defect surrounded by areas of contrast enhancement is a feature of embolus floating freely within the lumen.

Question 24

@# 75. A 24-year-old woman who is 28 weeks pregnant is admitted with suspected pulmonary embolism. As the on-call radiologist, her obstetrician contacts you seeking advice regarding further management. An admission CXR is normal. What investigation do you advise initially?

A. Venous ultrasound.

B. Low-dose CTPA.

C. Reduced dose lung scintigraphy.

D. MRA.

E. Catheter pulmonary angiography.

Answer 24

75. A. Venous ultrasound.

For pregnant patients, venous ultrasound is recommended before imaging tests with ionizing radiation are performed. Up to 29% of pregnant patients with PE will have a positive venous ultrasound, obviating the need for further imaging.

The majority of the PIOPED II investigators currently recommend V/Q scanning over CTPA in the evaluation of PE in pregnant patients. The foetal dose with V/Q is similar to that with CTPA, although the effective dose per breast is much greater with CTPA.

MRI requires further evaluation and gadolinium-based contrast agents have not been proven to be safe in pregnancy.

The role of catheter angiography is probably limited to those patients requiring mechanical thrombectomy.

It should be noted that even a combination of CXR, lung scintigraphy, CTPA, and pulmonary angiography exposes the foetus to approximately 1.5mGy of radiation, which is well below the accepted limit of 50 mGy for the induction of deterministic effects in the foetus. Stein PD, Woodard PK, Weg JG, Wakefield TW, Tapson VF, Sostman HD et al. Diagnostic pathways in acute pulmonary embolism: recommendations of the PIOPED II investigators.

Question 25

27 A 40-year-old female presented with shortness of breath and her chest radiograph was normal. She underwent a ventilation/perfusion study to investigate a possible pulmonary embolus. This showed two small, unmatched subsegmental defects in the left apical region. The ventilation images are normal. What is the correct report for this study?

a Normal study

b Very low probability

C Low probability

d High probability,

e Intermediate probability

Answer 25

27 Answer C: Low probability

The Prospective Investigation of Pulmonary Embolus Diagnosis (PIOPED) criteria give a range of findings that can be reported, from normal study to high probability. The reporter should be familiar with the segmental anatomy and these criteria and the report should be taken into account along with the clinical probability.

Question 26

@# 33 A patient with a known malignancy presented with acute shortness of breath. The attending physician requested CT pulmonary angiogram to exclude a pulmonary embolus. A filling defect was seen in the left lower pulmonary artery with a wedge-shaped collapse distal to it. Which primary tumour is most frequently associated with pulmonary embolism?

a Lung carcinoma

b Hepatocellular carcinoma

C Gastric carcinoma

d Ovarian cystadenoma

e Prostate carcinoma

Answer 26

33 Answer C: Gastric carcinoma

Ovarian carcinoma and extra hepatic bile duct carcinomas also demonstrate a high rate of pulmonary emboli.

Question 27

52 A 32-year-old artist presented with chest pain and dyspnoea. Physical examination was unremarkable but blood gas analysis showed her to be markedly hypoxic and a pulmonary embolus was suspected. A CT pulmonary angiogram (CTPA) was performed with bolus tracking (threshold triggering); however, the pulmonary arterial contrast opacification was sub-optimal. The intravenous cannula is well sited and there is no overt sign of swelling around the cannula site. The patient took a deep breath just prior to the scan and the scan appeared to trigger appropriately with the region of interest (ROI) sited over the main pulmonary artery. What is the most likely cause for the sub-optimal opacification of the pulmonary vessels?

a Left to right shunt

b Contrast extravasation at the injection site

C Right to left shunt

d Dilution of opacified blood with unopacified blood

e Hypodynamic circulation

Answer 27

52 Answer D: Dilution of opacified blood with unopacified blood

This is a common problem with the CTPA, especially with younger patients. As they take in a deep breath just prior to the scan their intrathoracic pressure is reduced and unopacified blood is drawn up from the IVC. This effectively dilutes the opacified blood entering from the SVC. One way to avoid this pitfall is to ask the patient to only take a modest breath prior to scanning.

Question 28

11 A 57-year-old woman presented with reduced exercise tolerance and shortness of breath. No specific abnormality was found on clinical examination. Chest radiography showed enlarged central pulmonary arteries and subsequent chest CT confirmed pulmonary artery enlargement and also showed right ventricular dilation. What additional feature would make chronic thromboembolism a more likely diagnosis than systemic to pulmonary circulation shunting?

a Pleural effusion

b Interstitial septal lines

C Mosaic attenuation

d Flattening of the interventricular septum

e Reflux of contrast into the inferior vena cava

Answer 28

11 Answer C: Mosaic attenuation

Mosaic attenuation is a common feature of chronic thromboembolism; it can be seen in left to right shunts but this is much less common and tends to be more diffuse.

Question 29

19 A 45-year-old gentleman underwent a contrast-enhanced CT scan of the thorax. His main pulmonary artery has a diameter greater than ascending aorta and the central pulmonary arteries are calcified. The peripheral pulmonary arteries have a pruned appearance. What is the likely pulmonary artery pressure?

a 0 mmHg

b 5 mmHg

c l0mmHg

d 15 mmHg

e 25 mmHg

Answer 29

19 Answer E: 25 mmHg

The above vignette describes pulmonary hypertension. The normal pulmonary arterial pressure is about 15 mmHg at rest and it is considered elevated if it measures above 25 mmHg.

Question 30

28 A 29-week pregnant patient presented with shortness of breath and hypoxia with pleuritic chest pain. Her chest radiograph was normal and no concurrent cardiopulmonary disease was present. Which is the most appropriate line of investigation to further investigate a pulmonary embolus?

a CT pulmonary angiogram with lead protection of the patient’s abdomen

b Cardiac echo to exclude intracardiac thrombus

c Reduced-dose ventilation/perfusion scan

d MUGA study

e Therapeutic dose heparin till delivery and definitive imaging

Answer 30

28 Answer C: Reduced-dose ventilation/perfusion scan

Ventilation/perfusion scans (V/Q) are considered the best form of imaging in pregnancy, especially in a fit patient with no chest disease. A reduced-dose study enables both perfusion and ventilation images to be performed at less than the conventional dose. A MUGA study looks at ejection fraction; cardiac echo may show evidence of right heart strain and large central PE but will not exclude segmental disease.

Question 31

53 A 34-year-old banker presented with dyspnoea on exertion and intermittent chest pain. She was slightly cyanosed and mildly hypoxic at rest, becoming more so on standing. A chest radiograph demonstrated a lobulated 3 -cm mass in the left lower zone with a small, rounded focus of calcification within it. `Cordlike’ bands are seen extending from the mass to the left hilum. What is the most likely diagnosis?

a Melanoma metastasis

b Pulmonary capillary haemangiomatosis

C Pulmonary hamartoma

d Angiomyolipoma

e Pulmonary arteriovenous malformation

Answer 31

53 Answer E: Pulmonary arteriovenous malformation

Orthodeoxia describes worsening hypoxia in the erect position due to gravitational shift of blood within the arteriovenous malformation (AVM). Seventy per cent of AVMs are located in the lower lobes, and small foci of calcification may be seen within them, representing phleboliths. The cordlike bands seen connecting the AVM to the hilum represent the feeding artery and draining vein.

Question 32

18 A 32-year-old intravenous drug user was admitted for management of a brain abscess. His medical records showed recurrent admissions with life-threatening epistaxis. Physical examination revealed multiple vascular blemishes on his lips, palate, conjunctiva and fingers. On chest auscultation, there was a bruit in the right lung base and a chest radiograph was performed. This showed a serpiginous mass in the right lower zone. What is the most likely underlying diagnosis?

a Sickle cell disease

b Factor V deficiency

c AIDS

d Hereditary haemorrhagic telangiectasia

e Vitamin K deficiency

Answer 32

18 Answer D: Hereditary haemorrhagic telangiectasia

Hereditary haemorrhagic telangiectasia is also known as Osler-Weber-Rendu syndrome and often presents with recurrent bleeding episodes (epistaxis, GI bleeding). It is the only condition of the options listed that is associated with pulmonary arteriovenous malformation (PAVM) and 50-60% of patients with PAVM have hereditary haemorrhagic telangiectasia. Ten to fifteen per cent of patients with hereditary haemorrhagic telangiectasia have PAVMs. With PAVMs, there is an extra-cardiac right-to-left shunt, which can result in paradoxical embolism. Brain abscesses can occur due to the loss of the normal pulmonary filter function. Screening first-degree relatives of patients with PAVMs is usually recommended as it is autosomally dominantly inherited.

Question 33

28 A 42-year-old woman presented after a long-haul flight with shortness of breath, hypoxia, tachycardia, new right bundle branch block on her ECG and pleuritic chest pain. No coexistent cardiopulmonary pathology is present. A chest radiograph taken 36 hours ago shows no abnormality. What is the next appropriate step according to the guidelines laid out by the British Thoracic Society?

a CT pulmonary angiography

b Ventilation/perfusion scan (V/Q)

C D dimer blood test

d Repeat chest radiograph

e Conventional pulmonary angiography

Answer 33

28 Answer B: Ventilation/perfusion scan (V/Q)

D dimer should not be performed in high-risk patients such as this and imaging is the next step. Conventional angiography is the gold standard but is invasive and not available in most centres. The normal CXR and absence of concurrent disease leaves V/Q as the most appropriate test.

Question 34

46 A 46-year-old female presented with a vague history of dyspnoea and chest pain. A chest radiograph demonstrated nonspecific findings of atelectasis, a small right-sided pleural effusion and patchy infiltrates. A CT pulmonary angiogram showed thrombus within the pulmonary arteries. What additional finding would be most suggestive of chronic rather than acute thromboembolic disease?

a A large volume of disease

b The presence of systemic hypertension

C Narrowing of the peripheral pulmonary vessels

d Enlargement of the pulmonary arteries

e Centrally placed thrombus

Answer 34

46 Answer C: Narrowing of the peripheral pulmonary vessels

The presence of enlarged pulmonary arteries on its own can be seen in acute and chronic thromboembolic disease, but narrowing of the peripheral vessels and often a mosaic attenuation pattern is much more suggestive of a chronic process.

Question 35

51 A 24-year-old primary school teacher presents to the acute medical unit with right-sided pleuritic chest pain and dyspnoea. She has never been unwell and takes no regular medication except the combined oral contraceptive pill. Examination is unremarkable except for tachypnoea and her oxygen saturations are 92 % on air. She refused arterial blood gas analysis. Her chest radiograph demonstrated right mid-zone opacification and a ventilation/ perfusion scan was arranged. What appearance would be most compatible with a diagnosis of pulmonary thromboembolism?

a Segmental perfusion defect much larger than an associated ventilation defect

b Sub-segmental matched ventilation/perfusion defect

C Non-segmental matched ventilation/perfusion defect

d Non-segmental mismatched perfusion defect

e Segmental matched ventilation/perfusion defect

Answer 35

51 Answer A: Segmental perfusion defect much larger than an associated ventilation defect

Matched/Mismatched defects:

A matched defect demonstrates both ventilation and perfusion abnormalities of similar size in the same region.

A mismatched defect displays reduced perfusion in an area of normal ventilation, or a much larger perfusion defect than ventilation abnormality – typical of PE.

Segmental/Sub-segmental/Nonsegmental defects: Occlusion of a segmental branch of the pulmonary artery will lead to a subpleural, wedgeshaped segmental perfusion defect - typical of PE.

Sub-segmental perfusion defects are smaller than a whole segment.

A non-segmental perfusion defect will not conform to segmental anatomy, that is will not appear wedge
shaped or sub-pleural.

Question 36

70 A 45-year-old woman with pleuritic chest pain, shortness of breath and profound hypoxia was suspected of having had a pulmonary embolus and a CT pulmonary angiogram was performed. Opacification of the pulmonary vasculature is good with a measured density of 212 HU. What window settings would be optimal when evaluating the pulmonary artery for thrombus?

a Window width 350 HU, window level 40 HU

b Window width 1500 HU, window level -500 HU

C Window width 700 HU, window level 100 HU

d Window width 1500HU, window level 500HU

e Window width 100 HU, window level 500HU

Answer 36

70 Answer C: Window width 700 HU, window level 100 HU

Question 37

5. A 50-year-old man with recently diagnosed pancreatic cancer presents with acute onset of chest pain and dyspnoea. The chest radiograph is normal. A V/Q scan is performed. Perfusion images show multiple segmental filling defects and the ventilation images show normal ventilation in equilibrium and washout images. The most likely diagnosis is?

(a) Pulmonary embolism

(b) Emphysema

(c) Chest infection

(d) Congestive heart failure

(e) Pulmonary artery stenosis

Answer 37

5. (a) Pulmonary embolism

This is the most likely diagnosis. If multiple ventilation-perfusion defects are seen in areas where there are no corresponding chest radiographic abnormalities, pulmonary embolism is highly probable. Rarely, vasculitis can produce such appearance, but the patient’s clinical history and presentation should allow accurate diagnosis.

Question 38

13. A 42-year-old female non-smoker presents with recurrent episodes of epistaxis, dyspnoea and occasional haemoptysis. The chest radiograph shows a 3 cm serpiginous nodule in the right mid zone with an apparent draining vessel from thehilum. The most likely diagnosis is?

(a) Neurilemmoma

(b) Hamartoma

(c) Pulmonary arteriovenous malformation

(d) Adenocarcinoma

(e) Post-primary tuberculosis

Answer 38

13. (c) Pulmonary arteriovenous malformation

70% of pulmonary arteriovenous malformations are associated with Osler–Weber– Rendu syndrome also called hereditary hemorrhagic telangiectasia (HHT) which is associated with multiorgan arteriovenous malformations.

A patient with HHT may present with epistaxis, GI bleeding, skin telangiectasia etc.

Chest radiography shows a sharply demarcated mass, typically round or oval, and feeding vessels can be seen from the hilum.

Contrastenhanced CT chest confirms abnormal communication between pulmonary arteries and pulmonary veins.

Question 39

19. A 45-year-old woman with a facial skin discoloration presents with a left-sided hemiparesis. The chest radiograph shows a 2 cm round mass in the left lower lobe. CT confirms the lung mass and shows an enlarged feeding artery and draining vein. No other chest abnormality is seen. What is the most likely diagnosis?

(a) Small cell lung cancer

(b) Metastasis

(c) Arteriovenous malformation

(d) Tuberculoma

(e) Rheumatoid nodule

Answer 39

19. (c) Arteriovenous malformation (AVM)

Patients with AVM present with cough, haemoptysis or occasionally with cerebral embolism. Fifty per cent of pulmonary AVMs are associated with Osler–Weber– Rendu disease (many have AVMs elsewhere, including the skin, mucous membranes and other organs).

Question 40

20. A 60-year-old patient under treatment for lymphoma presents with chest pain. The chest radiograph and blood results are normal. A V/Q scan shows normal perfusion and patchy areas of ventilation defects in the lungs. Which of the following is the unlikely diagnosis?

(a) Asthma

(b) Chronic obstructive pulmonary disease

(c) Acute bronchitis

(d) Sarcoidosis

(e) Pulmonary embolism

Answer 40

20. (e) Pulmonary embolism is the unlikely diagnosis

Pulmonary embolism will demonstrate abnormal perfusion defects with or without ventilation defects.

Question 41

4. Regarding diagnosis of pulmonary embolism (PE): (T/F)

(a) A negative D-dimer test reliably excludes PE in patients with low clinical probability.

(b) A positive D-dimer test is highly specific for PE.

(c) A normal isotope lung scan reliably excludes PE.

(d) Patients with a good quality negative CTPA do not require further investigation or treatment for PE.

(e) Digital subtraction pulmonary angiography is the investigation of choice for patients with suspected massive PE.

Answer 41

Answers:

(a) Correct

(b) Not correct

(c) Correct

(d) Correct

(e) Not correct

Explanation:

A positive D-dimer test has a poor specificity for PE, especially in hospitalized patients. CTPA or echocardiography is the investigations of choice in case of massive PE.