Page 15 of 17
RD7.3 | Imaging in Internal Medicine — Graded Quiz
Click any question card to reveal the correct answer.
A 70-year-old man presents 3 hours after sudden-onset slurred speech and left arm weakness. A non-contrast CT brain is performed. Which of the following is an EARLY CT sign of acute ischaemic stroke?
Correct. Early ischaemic signs on NCCT include loss of grey–white differentiation, the insular ribbon sign, and the hyperdense MCA sign. A well-established hypodensity indicates a more mature infarct, not a hyperacute one.
Early ischaemic CT signs: loss of grey–white differentiation, insular ribbon sign, and the hyperdense MCA sign. Established hypodensity is a later finding.
Subtle early ischaemic signs are loss of grey–white differentiation and effacement of the insular ribbon. A mature wedge-shaped hypodensity appears later; a biconvex hyperdense collection is an extradural haematoma.
Click to reveal answer
A patient with suspected acute stroke has a normal non-contrast CT brain within 2 hours of symptom onset, but the clinical deficit is striking. The team wants the most sensitive modality to confirm early ischaemia. Which is most appropriate?
Correct. A normal early NCCT does not exclude ischaemia. Diffusion-weighted MRI is more sensitive than CT and can demonstrate restricted diffusion within minutes of ischaemic onset.
DWI-MRI is more sensitive than CT for early ischaemia; a normal early NCCT does not exclude an acute infarct.
Although NCCT is the mandatory first study, it can be normal early in ischaemia. DWI-MRI is the more sensitive modality for confirming early ischaemic change.
Click to reveal answer
A 55-year-old man with breathlessness has a CTPA performed for suspected pulmonary embolism. Which CT finding directly confirms the diagnosis of pulmonary embolism?
Correct. The diagnostic CTPA finding of PE is a filling defect within the pulmonary arterial lumen. Wedge consolidation, effusion and diaphragm elevation are non-specific and may be absent.
An intraluminal filling defect on CTPA is the direct, confirmatory sign of pulmonary embolism.
The defining CTPA sign of PE is an intraluminal filling defect. The other findings are indirect/non-specific and do not by themselves confirm PE.
Click to reveal answer
On a CTPA confirming pulmonary embolism, the radiologist reports a right ventricle-to-left ventricle (RV/LV) diameter ratio greater than 1. What is the clinical significance of this finding?
Correct. An RV/LV ratio >1 on CTPA signifies right ventricular strain/dilatation and marks a higher-risk PE, which influences risk stratification and the consideration of escalated therapy.
An RV/LV ratio >1 on CTPA indicates right ventricular strain and marks a higher-risk PE, guiding risk stratification and management intensity.
The normal RV/LV ratio is <1. A ratio >1 indicates RV strain and a higher-risk PE — a confirmed PE is not a single disease but a spectrum stratified partly by RV function.
Click to reveal answer
A 75-year-old woman with acute breathlessness has a chest radiograph showing bilateral perihilar 'bat-wing' alveolar opacification, an enlarged cardiac silhouette and small bilateral pleural effusions. Which condition do these radiographic findings most strongly indicate?
Correct. Bat-wing (perihilar) alveolar opacification with cardiomegaly and pleural effusions is the classic radiographic picture of alveolar pulmonary oedema from heart failure.
Bat-wing perihilar alveolar oedema with cardiomegaly and effusions indicates cardiogenic pulmonary oedema from heart failure.
The combination of perihilar bat-wing alveolar oedema, cardiomegaly and bilateral effusions points to cardiogenic pulmonary oedema. Lobar pneumonia is typically focal; pneumothorax and hyperinflation give very different appearances.
Click to reveal answer
Echocardiography is performed in a 66-year-old man with confirmed heart failure on chest radiograph. The ejection fraction is reported as 32%. How should this be classified?
Correct. An ejection fraction below 40% defines heart failure with reduced ejection fraction (HFrEF). This classification directs the use of evidence-based disease-modifying therapy.
EF <40% on echocardiography defines HFrEF; classifying by EF directs disease-modifying therapy in heart failure.
An EF of 32% (<40%) is HFrEF. HFpEF is defined by a preserved EF (typically ≥50%) with clinical heart failure. Echo-derived EF is the key parameter that classifies failure and guides treatment.
Click to reveal answer
A 52-year-old man with chronic hepatitis B undergoes liver ultrasound. The report describes a small liver with a coarse, nodular surface and signs of portal hypertension. Which diagnosis do these ultrasound findings most strongly suggest?
Correct. A small liver with a coarse, nodular surface together with features of portal hypertension is the characteristic ultrasound picture of cirrhosis.
Cirrhosis on ultrasound: nodular/coarse, often shrunken liver with portal hypertensive features — distinct from the smooth, bright liver of simple steatosis.
Cirrhosis shows a nodular, coarse-textured liver, often shrunken, with portal hypertensive features. Simple steatosis shows a smooth, bright (echogenic) liver without nodularity or portal hypertension.
Click to reveal answer
A 64-year-old man with cirrhosis and an eGFR of 24 mL/min/1.73m² needs further characterisation of a liver lesion. Which statement about contrast use is most appropriate?
Correct. With an eGFR <30, iodinated CT contrast must be used cautiously given the risk of contrast-associated nephropathy. Ultrasound (radiation- and contrast-free) is the first-line and surveillance tool, and 6-monthly USG ± AFP surveillance remains indicated in cirrhosis.
Use iodinated CT contrast cautiously when eGFR <30; ultrasound is the contrast-free first-line and surveillance modality, with 6-monthly USG ± AFP in cirrhosis.
Iodinated contrast requires caution when eGFR is below 30. Ultrasound is the radiation- and contrast-free first-line study and the recommended HCC surveillance tool (6-monthly USG ± AFP), making it well suited to this patient.
Click to reveal answer