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EDiR practice questions

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Question 1Chest and cardiovascular radiology

A frontal chest radiograph shows air-space opacification that obscures the right heart border but leaves the right hemidiaphragm clearly visible. Which lobe is involved?

  1. Right upper lobe
  2. Right middle lobe Correct answer.
  3. Left lower lobe
  4. Right lower lobe

Explanation

The right middle lobe lies against the right heart border, so opacification there effaces that border while sparing the diaphragm - the silhouette sign. The right lower lobe abuts the hemidiaphragm rather than the cardiac contour.

Question 2Chest and cardiovascular radiology

On an erect postero-anterior chest radiograph, a cardiothoracic ratio greater than which value indicates cardiomegaly?

  1. 0.5 Correct answer.
  2. 0.4
  3. 0.7
  4. 0.6

Explanation

Cardiomegaly is defined as a maximal cardiac transverse diameter exceeding half the maximum internal thoracic diameter on an erect PA radiograph. Portable AP films magnify the heart and are unreliable for this measurement.

Question 3Chest and cardiovascular radiology

On high-resolution CT, a bronchus whose diameter exceeds that of its accompanying pulmonary artery is described as which sign?

  1. Tree-in-bud pattern
  2. Air bronchogram
  3. Halo sign
  4. Signet-ring sign Correct answer.

Explanation

A bronchus dilated relative to its companion artery produces the signet-ring sign, a hallmark of bronchiectasis. Normally the two structures are of similar calibre, with the bronchus slightly smaller.

Question 4Chest and cardiovascular radiology

Short horizontal lines reaching the pleura at the lung bases on a frontal chest radiograph represent which structure?

  1. Thickened fissures
  2. Thickened interlobular septa Correct answer.
  3. Pleural plaques
  4. Bronchial wall thickening

Explanation

Kerley B lines are peripheral septal lines lying perpendicular to the pleura at the bases and reflect interlobular septal oedema, typically in interstitial pulmonary oedema. They are short, straight and parallel to each other.

Question 5Chest and cardiovascular radiology

A supine chest radiograph in a trauma patient shows an abnormally deep, lucent costophrenic angle with a sharply outlined hemidiaphragm. This appearance indicates which finding?

  1. Diaphragmatic rupture
  2. Basal atelectasis
  3. Pleural effusion
  4. Pneumothorax Correct answer.

Explanation

In a supine patient, pleural air collects anterobasally and deepens the costophrenic angle - the deep sulcus sign. Erect films instead show apical pleural gas with a visible visceral pleural line.

Question 6Chest and cardiovascular radiology

A well-defined anterior mediastinal mass in a young adult contains macroscopic fat and coarse calcification. What is the most likely diagnosis?

  1. Mature teratoma Correct answer.
  2. Retrosternal goitre
  3. Thymoma
  4. Lymphoma

Explanation

The combination of fat, fluid and calcification (often tooth or bone) within an anterior mediastinal mass in a young adult is characteristic of a mature teratoma. Thymoma and lymphoma are usually soft-tissue density without fat.

Question 7Chest and cardiovascular radiology

CT aortography shows a dissection flap involving the ascending aorta and extending into the arch. How is this classified?

  1. DeBakey type III
  2. Stanford type A Correct answer.
  3. Stanford type B
  4. Isolated intramural haematoma

Explanation

Stanford type A dissection involves the ascending aorta regardless of the site of the intimal tear, and it is a surgical emergency. Type B dissection spares the ascending aorta.

Question 8Chest and cardiovascular radiology

A 1.5 cm well-defined pulmonary nodule contains fat attenuation and popcorn-like calcification. What is the most likely diagnosis?

  1. Bronchogenic carcinoma
  2. Solitary metastasis
  3. Pulmonary hamartoma Correct answer.
  4. Typical carcinoid tumour

Explanation

Fat within a pulmonary nodule, particularly with popcorn calcification, is characteristic of a hamartoma and usually allows a benign diagnosis without biopsy. Malignant nodules very rarely contain macroscopic fat.

Question 9Chest and cardiovascular radiology

High-resolution CT shows basal and subpleural predominant reticulation with honeycombing and traction bronchiectasis, with only minor ground-glass opacity. Which pattern does this represent?

  1. Pulmonary alveolar proteinosis
  2. Usual interstitial pneumonia Correct answer.
  3. Hypersensitivity pneumonitis
  4. Organising pneumonia

Explanation

Basal, subpleural reticulation with honeycombing and traction bronchiectasis, with ground-glass change limited to the fibrotic areas, defines the usual interstitial pneumonia pattern. This pattern is the radiological hallmark of idiopathic pulmonary fibrosis.

Question 10Chest and cardiovascular radiology

A ventilated patient becomes hypotensive and a radiograph shows a large right pneumothorax with mediastinal shift to the left. What is the appropriate immediate step?

  1. Aspirate the contralateral pleural space
  2. Decompress the pleural space without waiting for further imaging Correct answer.
  3. Insert a chest drain once imaging has been reviewed
  4. Transfer for CT to confirm the diagnosis

Explanation

Tension pneumothorax is a clinical diagnosis and requires immediate needle or finger decompression followed by a chest drain. Delay for imaging or transfer risks cardiac arrest.

Question 11Chest and cardiovascular radiology

Contrast-enhanced CT shows a large pericardial effusion with diastolic flattening of the right ventricular free wall. What does this finding suggest?

  1. Cardiac tamponade Correct answer.
  2. Right ventricular hypertrophy
  3. Constrictive pericarditis
  4. Pericardial cyst

Explanation

Diastolic collapse or flattening of the right ventricular free wall reflects failure of ventricular filling under high pericardial pressure, indicating tamponade physiology. The finding should be interpreted together with the patient's haemodynamics.

Question 12Chest and cardiovascular radiology

A frontal radiograph shows a focal area of increased lucency with reduced vascular markings in one mid zone. This is known as which sign of pulmonary embolism?

  1. Golden S sign
  2. Hampton hump
  3. Fleischner sign
  4. Westermark sign Correct answer.

Explanation

Westermark sign is regional oligaemia distal to an embolus, producing a lucent zone with diminished vessels. It is a sign of acute pulmonary embolism on plain film.

Question 13Chest and cardiovascular radiology

High-resolution CT in an asymptomatic patient shows numerous small nodules distributed along bronchovascular bundles, fissures and the pleura, with bilateral symmetrical hilar lymphadenopathy. What is the most likely diagnosis?

  1. Sarcoidosis Correct answer.
  2. Pulmonary Langerhans cell histiocytosis
  3. Idiopathic pulmonary fibrosis
  4. Miliary tuberculosis

Explanation

Perilymphatic nodules with bilateral symmetrical hilar adenopathy are typical of sarcoidosis. The distribution along fissures and pleura is a key discriminator from haematogenous (random) patterns.

Question 14Chest and cardiovascular radiology

In an asymptomatic adult, elective surgical repair of an ascending thoracic aortic aneurysm is generally considered once the maximum diameter exceeds which value?

  1. 5.5 cm Correct answer.
  2. 4.5 cm
  3. 3.5 cm
  4. 4.0 cm

Explanation

For the ascending aorta, elective repair is usually offered at about 5.5 cm, or earlier at around 5.0 cm when there is rapid growth, a bicuspid valve or a family history. The descending aorta threshold is higher, at about 6.0 cm.

Question 15Chest and cardiovascular radiology

Acute cardiogenic pulmonary oedema produces perihilar alveolar opacification that fades towards the periphery. What is this appearance called?

  1. Bat-wing appearance Correct answer.
  2. Silhouette sign
  3. Westermark sign
  4. Golden S sign

Explanation

Perihilar air-space opacification with peripheral sparing creates the bat-wing or butterfly pattern of alveolar pulmonary oedema. It reflects fluid accumulating in the dependent perihilar lung.

Question 16Chest and cardiovascular radiology

A 60-year-old heavy smoker has a 5 cm cavitating mass with thick, irregular walls in the right upper lobe. What is the most likely diagnosis?

  1. Post-primary tuberculosis
  2. Squamous cell carcinoma Correct answer.
  3. Granulomatosis with polyangiitis
  4. Lung abscess

Explanation

A thick-walled, irregularly margined cavity in an upper lobe of a smoker is most often a cavitating squamous cell carcinoma. Cavitation occurs as the tumour outgrows its blood supply.

Question 17Chest and cardiovascular radiology

Cardiac MRI shows diffuse subendocardial late gadolinium enhancement with abnormal myocardial nulling occurring before the blood pool. What is the most likely diagnosis?

  1. Hypertrophic cardiomyopathy
  2. Cardiac amyloidosis Correct answer.
  3. Cardiac sarcoidosis
  4. Acute myocarditis

Explanation

Global subendocardial enhancement combined with difficulty nulling the myocardium - which nulls before the blood pool - is characteristic of cardiac amyloidosis. The expanded extracellular space alters gadolinium kinetics.

Question 18Chest and cardiovascular radiology

Which CT pulmonary angiographic finding is most specific for chronic thromboembolic pulmonary hypertension?

  1. Unilateral pleural effusion
  2. Eccentric mural thrombus with intimal webs and bands Correct answer.
  3. Contrast reflux into the inferior vena cava
  4. Central filling defect surrounded by contrast

Explanation

Chronic thromboemboli become incorporated into the vessel wall, giving eccentric mural thrombus, webs, bands and pouch defects, often with mosaic perfusion. Acute emboli instead appear as central defects outlined by contrast.

Question 19Chest and cardiovascular radiology

In hypertrophic cardiomyopathy, dynamic left ventricular outflow tract obstruction is most commonly produced by which mechanism?

  1. Aortic valve calcification
  2. Apical cavity obliteration
  3. Systolic anterior motion of the mitral valve Correct answer.
  4. Left ventricular dilatation

Explanation

Asymmetric septal hypertrophy narrows the outflow tract, and the resulting Venturi effect draws the anterior mitral leaflet forward in systole - systolic anterior motion - which further obstructs outflow and causes mitral regurgitation.

Question 20Chest and cardiovascular radiology

A 30-year-old with recurrent epistaxis and a family history of similar symptoms has a rounded pulmonary opacity with a feeding artery and a draining vein on CT. Which underlying condition is most likely?

  1. Marfan syndrome
  2. Hereditary haemorrhagic telangiectasia Correct answer.
  3. Tuberous sclerosis
  4. Neurofibromatosis type 1

Explanation

A pulmonary arteriovenous malformation with a visible feeding artery and draining vein, together with epistaxis and a positive family history, points to hereditary haemorrhagic telangiectasia. Screening for cerebral and hepatic vascular malformations is then warranted.

Question 21Abdominal and gastrointestinal radiology

A 45-year-old woman has an incidental 3 cm well-defined liver lesion. On dynamic MRI it shows discontinuous peripheral nodular enhancement after gadolinium, with progressive centripetal fill-in on delayed phases. What is the most likely diagnosis?

  1. Hepatocellular carcinoma
  2. Focal nodular hyperplasia
  3. Cavernous haemangioma Correct answer.
  4. Hepatic adenoma

Explanation

Slow centripetal fill-in from discontinuous peripheral nodules reflects gradual opacification of large vascular spaces and is the classic haemangioma pattern. The lesion remains isointense to blood pool on delayed phases and shows no washout.

Question 22Abdominal and gastrointestinal radiology

CT of a 70-year-old with previous laparotomy and vomiting shows dilated fluid-filled small bowel loops with a discrete transition zone and collapsed distal bowel. What is the most likely diagnosis?

  1. Infective enterocolitis
  2. Small bowel obstruction Correct answer.
  3. Acute mesenteric ischaemia
  4. Paralytic ileus

Explanation

A transition zone with proximally dilated and distally collapsed bowel is the hallmark of mechanical obstruction and usually indicates adhesions in a patient with prior surgery. Ileus instead produces diffuse dilation without a transition point.

Question 23Abdominal and gastrointestinal radiology

Which ultrasound finding is the primary criterion for acute appendicitis?

  1. Normal-calibre appendix that compresses fully
  2. Fat stranding without a visible appendix
  3. Aperistaltic tubular structure over 6 mm Correct answer.
  4. Appendicolith without wall thickening

Explanation

The diagnosis rests on a blind-ending, non-compressible tubular structure with an outer diameter greater than 6 mm, often accompanied by aperistalsis, wall thickening and peri-appendiceal fat stranding. Compression is the key manoeuvre because a normal appendix collapses.

Question 24Abdominal and gastrointestinal radiology

Barium swallow shows a dilated oesophagus with smooth tapering at the gastro-oesophageal junction and absent primary peristalsis. What is the most likely diagnosis?

  1. Scleroderma oesophagus
  2. Diffuse oesophageal spasm
  3. Oesophageal carcinoma
  4. Achalasia Correct answer.

Explanation

Smooth symmetrical tapering at the gastro-oesophageal junction with a dilated aperistaltic oesophagus is the classic bird-beak appearance of achalasia, caused by failure of lower oesophageal sphincter relaxation. Carcinoma produces an irregular, shouldered stricture.

Question 25Abdominal and gastrointestinal radiology

A 60-year-old with left lower quadrant pain has CT showing colonic wall thickening, pericolic fat stranding and multiple diverticula, with no abscess or free gas. What is the most likely diagnosis?

  1. Ulcerative colitis
  2. Acute diverticulitis Correct answer.
  3. Colorectal carcinoma
  4. Ischaemic colitis

Explanation

Segmental wall thickening with pericolic fat stranding in a colon bearing diverticula, typically the sigmoid, indicates acute diverticulitis. The absence of an abscess or extraluminal gas corresponds to uncomplicated disease.

Question 26Abdominal and gastrointestinal radiology

Which contrast agent is most appropriate for a contrast swallow in a patient with suspected oesophageal perforation?

  1. Barium sulphate suspension
  2. Water-soluble contrast Correct answer.
  3. Gadolinium chelate
  4. Carbon dioxide gas

Explanation

Leakage of barium into the mediastinum or peritoneum provokes severe granulomatous inflammation, so a water-soluble iodinated agent is used first. If that study is negative and suspicion remains high, barium can then be given for greater sensitivity.

Question 27Abdominal and gastrointestinal radiology

A 60-year-old with cirrhosis has a 2 cm liver nodule showing arterial-phase hyperenhancement, washout in the portal venous phase and a thin enhancing capsule. What is the LI-RADS category?

  1. LR-5 Correct answer.
  2. LR-4
  3. LR-3
  4. LR-M

Explanation

In a cirrhotic liver, a nodule of 10 mm or more with non-rim arterial hyperenhancement plus at least one additional major feature, such as washout or capsule, is LR-5, indicating definite hepatocellular carcinoma.

Question 28Abdominal and gastrointestinal radiology

MRCP in a patient with obstructive jaundice shows a rounded signal void within a dilated common bile duct, with upstream duct dilatation. What is the most likely cause?

  1. Primary sclerosing cholangitis
  2. Pancreatic head carcinoma
  3. Common bile duct stone Correct answer.
  4. Cholangiocarcinoma

Explanation

Bile is strongly hyperintense on heavily T2-weighted MRCP sequences, so a stone appears as a rounded intraluminal filling defect, often with a meniscus and a dilated duct above it.

Question 29Abdominal and gastrointestinal radiology

A 65-year-old with painless jaundice and weight loss has a pancreatic-protocol CT showing a hypoenhancing mass in the pancreatic head with dilatation of both the common bile duct and the main pancreatic duct. What is the most likely diagnosis?

  1. Autoimmune pancreatitis
  2. Ductal adenocarcinoma Correct answer.
  3. Serous cystadenoma
  4. Acute pancreatitis

Explanation

A hypoenhancing mass causing simultaneous dilatation of both ducts, the double duct sign, is characteristic of pancreatic ductal adenocarcinoma. Tumour hypovascularity relative to normal pancreas is best seen in the pancreatic parenchymal phase.

Question 30Abdominal and gastrointestinal radiology

A young woman has a liver lesion that is homogeneously hyperenhancing in the arterial phase, becomes isointense to liver in the portal venous and delayed phases, and contains a central T2-hyperintense scar. What is the most likely diagnosis?

  1. Metastasis
  2. Haemangioma
  3. Hepatic adenoma
  4. Focal nodular hyperplasia Correct answer.

Explanation

Homogeneous arterial enhancement except for a central scar, which enhances on delayed phases, with no washout, is typical of focal nodular hyperplasia. The scar is T2 hyperintense and the lesion remains isointense to liver on later phases.

Question 31Abdominal and gastrointestinal radiology

MRCP shows multifocal short strictures alternating with mildly dilated ducts, giving a beaded appearance, in a patient with ulcerative colitis. What is the most likely diagnosis?

  1. Primary biliary cholangitis
  2. Caroli disease
  3. Primary sclerosing cholangitis Correct answer.
  4. IgG4-related cholangitis

Explanation

Multifocal short strictures with intervening normal or dilated segments producing a beaded ductal tree, especially in inflammatory bowel disease, is the classic MRCP pattern of primary sclerosing cholangitis.

Question 32Abdominal and gastrointestinal radiology

MR enterography shows transmural inflammation, skip lesions with normal intervening bowel, and creeping fat in the terminal ileum. Which disease does this pattern most suggest?

  1. Ulcerative colitis
  2. Radiation enteritis
  3. Ischaemic colitis
  4. Crohn disease Correct answer.

Explanation

Skip lesions, transmural inflammation, creeping fat and a predilection for the terminal ileum are features of Crohn disease. Ulcerative colitis is continuous and confined to the mucosa.

Question 33Abdominal and gastrointestinal radiology

CT angiography in a patient with atrial fibrillation and severe abdominal pain shows a filling defect in the superior mesenteric artery with thin-walled dilated small bowel loops showing absent mural enhancement. What is the diagnosis?

  1. Neutropenic enterocolitis
  2. Mechanical small bowel obstruction
  3. Epiploic appendagitis
  4. Arterial mesenteric ischaemia Correct answer.

Explanation

An embolic filling defect in the superior mesenteric artery with non-enhancing bowel wall indicates acute arterial mesenteric ischaemia. Thin-walled dilated loops with absent enhancement reflect transmural infarction rather than obstruction.

Question 34Abdominal and gastrointestinal radiology

CT shows diffuse thickening of the gastric wall with a narrowed, poorly distensible lumen and no discrete exophytic mass. Which diagnosis should be considered?

  1. Menetrier disease
  2. Scirrhous gastric carcinoma Correct answer.
  3. Gastrointestinal stromal tumour
  4. Gastric lipoma

Explanation

Diffuse intramural infiltration producing a rigid, narrowed stomach is the linitis plastica pattern of scirrhous gastric carcinoma. It often involves a long segment without a discrete mass.

Question 35Abdominal and gastrointestinal radiology

On pelvic MRI, a rectal tumour extends to within 1 mm of the mesorectal fascia. What does this imply?

  1. Tumour is confined to the submucosa
  2. No neoadjuvant therapy is needed
  3. Extramural venous invasion is absent
  4. Circumferential margin is threatened Correct answer.

Explanation

Tumour within 1 mm of the mesorectal fascia predicts involvement of the circumferential resection margin and identifies a high-risk group for local recurrence. Such patients are considered for neoadjuvant chemoradiotherapy.

Question 36Abdominal and gastrointestinal radiology

Small bowel follow-through in a patient with malabsorption shows dilatation of jejunal loops, loss of jejunal folds and increased ileal folds. What is the most likely diagnosis?

  1. Whipple disease
  2. Intestinal tuberculosis
  3. Coeliac disease Correct answer.
  4. Radiation enteritis

Explanation

Coeliac disease causes fold reversal, with loss of jejunal folds and jejunisation of the ileum, together with loop dilatation and flocculation of barium. Transient non-obstructing intussusception may also occur.

Question 37Abdominal and gastrointestinal radiology

A patient had severe acute pancreatitis 5 weeks ago. CT shows a well-defined encapsulated collection with heterogeneous non-enhancing material replacing pancreatic parenchyma. What is this collection?

  1. Pancreatic pseudocyst
  2. Walled-off necrosis Correct answer.
  3. Acute necrotic collection
  4. Acute peripancreatic fluid collection

Explanation

Under the revised Atlanta classification, an encapsulated collection arising more than 4 weeks after necrotising pancreatitis and containing solid necrotic debris is walled-off necrosis. A pseudocyst is by definition homogeneous fluid without necrosis.

Question 38Abdominal and gastrointestinal radiology

CT after blunt abdominal trauma shows a focal rounded collection of contrast within the spleen that matches arterial attenuation and persists on delayed imaging. What does this represent?

  1. Splenic laceration
  2. Splenic infarct
  3. Traumatic pseudoaneurysm Correct answer.
  4. Subcapsular haematoma

Explanation

Focal contrast pooling isointense to arteries on arterial and delayed phases represents a contained vascular injury, or pseudoaneurysm, which carries a high risk of delayed rupture and usually requires angiographic embolisation.

Question 39Abdominal and gastrointestinal radiology

CT shows low-attenuation mucinous ascites with scalloping of the hepatic margin and a calcified appendiceal mass. What is the most likely diagnosis?

  1. Peritoneal mesothelioma
  2. Peritoneal carcinomatosis from colon cancer
  3. Pseudomyxoma peritonei Correct answer.
  4. Tuberculous peritonitis

Explanation

Mucinous ascites producing scalloping of solid organ surfaces, together with an appendiceal lesion, is characteristic of pseudomyxoma peritonei arising from a mucinous appendiceal neoplasm.

Question 40Abdominal and gastrointestinal radiology

An elderly, thin woman with small bowel obstruction has medial thigh pain. CT shows a bowel loop passing between the pectineus and obturator externus muscles. Which hernia is this?

  1. Obturator hernia Correct answer.
  2. Spigelian hernia
  3. Femoral hernia
  4. Inguinal hernia

Explanation

An obturator hernia passes through the obturator canal between the pectineus and obturator externus muscles and classically affects elderly, emaciated women. Compression of the obturator nerve produces the Howship-Romberg sign of medial thigh pain.

Question 41Genitourinary radiology

A 40-year-old presents with acute flank pain and haematuria. Which investigation is first-line for suspected ureteric colic?

  1. Intravenous urography with delayed abdominal films
  2. Ultrasound of the kidneys and bladder
  3. Non-contrast CT of the urinary tract Correct answer.
  4. MRI of the urinary tract with contrast

Explanation

Non-contrast CT detects almost all urinary calculi, including radiolucent uric acid stones, and identifies alternative causes of flank pain within minutes without iodinated contrast.

Question 42Genitourinary radiology

Which histological subtype accounts for the majority of renal cell carcinomas?

  1. Clear cell renal cell carcinoma Correct answer.
  2. Papillary renal cell carcinoma
  3. Chromophobe renal cell carcinoma
  4. Collecting duct carcinoma

Explanation

Clear cell renal cell carcinoma accounts for roughly 70–75% of sporadic renal cell carcinomas and is associated with inactivation of the VHL gene on chromosome 3p.

Question 43Genitourinary radiology

A 15-year-old has sudden severe scrotal pain. Which Doppler ultrasound finding favours testicular torsion over epididymo-orchitis?

  1. Increased blood flow in the epididymis
  2. Enlarged testis with a reactive hydrocele
  3. Hyperaemia of the testicular parenchyma
  4. Absent or reduced intratesticular arterial flow Correct answer.

Explanation

Torsion obstructs the spermatic cord vessels, so intratesticular arterial flow is reduced or absent and may be accompanied by an abnormal cord twist; inflammatory conditions instead increase flow.

Question 44Genitourinary radiology

Which unenhanced CT feature best supports a diagnosis of a lipid-rich adrenal adenoma?

  1. Delayed enhancement after contrast medium
  2. Attenuation greater than 30 HU
  3. Homogeneous attenuation below 10 HU Correct answer.
  4. Heterogeneous attenuation with calcification

Explanation

Intracellular lipid lowers the unenhanced attenuation of adenomas, and a homogeneous value of 10 HU or less is highly specific for a lipid-rich adenoma.

Question 45Genitourinary radiology

What is the most common histological type of bladder malignancy in adults?

  1. Squamous cell carcinoma
  2. Small cell carcinoma
  3. Urothelial carcinoma Correct answer.
  4. Adenocarcinoma

Explanation

Urothelial (transitional cell) carcinoma constitutes about 90% of bladder cancers in populations where schistosomiasis is uncommon.

Question 46Genitourinary radiology

In PI-RADS v2.1, which sequence is the dominant determinant of the score for a lesion in the peripheral zone?

  1. Dynamic contrast-enhanced imaging
  2. Diffusion-weighted imaging Correct answer.
  3. MR spectroscopy
  4. T2-weighted imaging

Explanation

PI-RADS v2.1 assigns diffusion-weighted imaging, including the ADC map, as the dominant sequence in the peripheral zone, whereas T2-weighted imaging dominates in the transition zone.

Question 47Genitourinary radiology

A 4 cm renal cyst contains multiple hairline septa with minimal smooth thickening and no measurable enhancement or nodularity. What is the correct Bosniak category?

  1. Bosniak III
  2. Bosniak II
  3. Bosniak IIF Correct answer.
  4. Bosniak I

Explanation

Minimal smooth septal or wall thickening upgrades a simple cyst from Bosniak II to Bosniak IIF, which requires imaging follow-up because the risk of malignancy is low but not negligible.

Question 48Genitourinary radiology

A 3 cm well-defined renal mass contains regions of fat attenuation (-80 HU) and enhancing soft tissue. Which diagnosis is most likely?

  1. Renal oncocytoma
  2. Papillary renal cell carcinoma
  3. Renal metastasis
  4. Angiomyolipoma Correct answer.

Explanation

Macroscopic fat within an enhancing renal mass is the hallmark of a classic angiomyolipoma, a benign tumour composed of vessels, smooth muscle and fat.

Question 49Genitourinary radiology

Which injury corresponds to American Association for the Surgery of Trauma grade V renal trauma?

  1. Laceration through the cortex into the medulla
  2. Shattered kidney or main pedicle avulsion Correct answer.
  3. Cortical laceration less than 1 cm deep
  4. Subcapsular haematoma with no parenchymal injury

Explanation

Grade V denotes catastrophic injury, namely a completely shattered kidney or avulsion of the renal hilum, both of which threaten renal viability and may require urgent intervention.

Question 50Genitourinary radiology

On multiparametric MRI, which finding is the most reliable sign of extraprostatic extension of prostate cancer (stage T3a)?

  1. Bulging of the prostatic capsule without irregularity
  2. Asymmetry of peripheral zone signal
  3. Irregular capsular breach by tumour Correct answer.
  4. Tumour contact with the capsule over 5 mm

Explanation

Frank tumour breaching the capsule with an irregular capsular contour is a direct sign of extraprostatic extension, supported by obliteration of the rectoprostatic angle or encasement of the neurovascular bundle.