Diagnostic Radiology Prometric exam questions

The Diagnostic Radiology exam in every GCC country

From each regulator's own exam pages; anything a regulator does not publish says so. Assessment mode also depends on your licence title, so confirm your route on your eligibility notice.

12 worked Diagnostic Radiology practice questions

Original exam-style questions from the bank, spread across the blueprint domains. They are not real or recalled exam questions. Try each one, then open the answer for the rationale and reference. None of them appear in the free mock exam, so reading them will not spoil it.

1. Question 1 · Body Imaging (Gastrointestinal, Hepatobiliary, Genitourinary and Abdominopelvic)

   Doppler ultrasound of a renal allograft three days after transplantation shows a resistive index of 0.95 in the interlobar arteries with reversed end-diastolic flow, and Doppler of a liver allograft in a different patient shows a hepatic artery resistive index of 0.4 with a systolic acceleration time of 0.15 seconds and a tardus-parvus waveform. Which interpretation is correct?

   1. ABoth findings indicate venous outflow obstruction in the respective grafts
   2. BThe renal finding suggests severe graft dysfunction requiring urgent evaluation; the hepatic finding suggests hepatic artery stenosis
   3. CThe renal finding is a normal early post-transplant appearance; the hepatic finding indicates hepatic artery thrombosis
   4. DBoth findings are within normal limits for the first postoperative week
   Show answer and explanation

   Correct answer: B. The renal finding suggests severe graft dysfunction requiring urgent evaluation; the hepatic finding suggests hepatic artery stenosis

   A resistive index of 0.95 with reversed diastolic flow in a renal allograft is markedly abnormal and non-specific for severe parenchymal dysfunction from acute rejection, acute tubular necrosis or renal vein thrombosis, and it demands urgent clinical and often surgical evaluation. In the hepatic artery, a tardus-parvus waveform with resistive index below 0.5 and acceleration time above 0.08 seconds indicates a proximal stenosis. Hepatic artery thrombosis would show absent rather than damped intrahepatic arterial signal. Neither pattern is a normal early post-transplant finding, and neither is specific for venous outflow obstruction, which produces its own abnormal venous waveforms.

   Reference: Sidhu PS et al., 'Ultrasound of the Transplant Kidney and Liver', Ultrasound Clinics / EFSUMB Guidelines, 2017; Crossin JD et al., 'US of Liver Transplants: Normal and Abnormal', RadioGraphics (RSNA), 2003

2. Question 2 · Musculoskeletal Imaging

   A 66-year-old man with smouldering myeloma has no CRAB features on laboratory testing. Whole-body MRI is performed. According to the International Myeloma Working Group criteria, which MRI finding by itself defines multiple myeloma requiring therapy?

   1. ADiffusely heterogeneous ('salt-and-pepper') marrow signal without discrete lesions
   2. BMore than one unequivocal focal lesion measuring at least 5 mm
   3. CA single focal lesion measuring 4 mm
   4. DAny high signal on STIR images within the axial marrow
   Show answer and explanation

   Correct answer: B. More than one unequivocal focal lesion measuring at least 5 mm

   The IMWG updated criteria include, among the myeloma-defining events, more than one focal lesion of at least 5 mm on MRI, which upgrades smouldering myeloma to symptomatic disease requiring treatment. A single focal lesion, sub-5 mm lesions, or a variegated/heterogeneous marrow pattern do not meet the threshold and are managed with repeat imaging, and non-specific STIR hyperintensity can reflect degenerative or haematopoietic change.

   Reference: Rajkumar SV et al. International Myeloma Working Group updated criteria for the diagnosis of multiple myeloma. Lancet Oncology 2014; MY-RADS (Messiou C et al., Radiology 2019)

3. Question 3 · Paediatric Imaging

   A four-year-old has a heterogeneous, calcified, mildly enhancing posterior fossa mass arising from the floor of the fourth ventricle that extends laterally through the foramen of Luschka into the cerebellopontine angle and inferiorly through the foramen magnum, moulding around the medulla. What is the most likely diagnosis?

   1. AEpendymoma
   2. BMedulloblastoma
   3. CAtypical teratoid/rhabdoid tumour
   4. DBrainstem (diffuse midline) glioma
   Show answer and explanation

   Correct answer: A. Ependymoma

   Extension of a fourth-ventricular tumour through the foramina of Luschka and Magendie while moulding to surrounding structures - the 'plastic' tumour - with frequent calcification is characteristic of posterior fossa ependymoma. Medulloblastoma is usually a more spherical midline mass with marked diffusion restriction that displaces rather than extrudes through the foramina; ATRT occurs in children under three and is typically large, haemorrhagic and off-midline; a diffuse midline glioma expands the pons itself rather than filling the fourth ventricle.

   Reference: WHO Classification of Tumours of the Central Nervous System, 5th ed. (2021); Caffey's Pediatric Diagnostic Imaging, 13th ed. (2019)

4. Question 4 · Women's Imaging (Breast, Obstetric and Gynaecologic)

   In a screening mammography audit of 1000 examinations, 100 women were recalled (BI-RADS 0), 20 of whom were ultimately given a biopsy recommendation (BI-RADS 4 or 5), and 5 cancers were diagnosed. What is the positive predictive value for biopsy recommended (PPV2)?

   1. A5%
   2. B20%
   3. C25%
   4. D50%
   Show answer and explanation

   Correct answer: C. 25%

   PPV2 is the number of cancers divided by the number of examinations for which biopsy was recommended, i.e. 5/20 = 25%. PPV1 (based on abnormal screening interpretations) would be 5/100 = 5%, and the cancer detection rate here is 5 per 1000. PPV3 is calculated only from biopsies actually performed, which is not given.

   Reference: ACR BI-RADS Atlas, 5th edition, Follow-up and Outcome Monitoring chapter (2013)

5. Question 5 · Head and Neck Imaging

   A 7-year-old child has fluctuating, stepwise progressive bilateral sensorineural hearing loss, worse after minor head trauma. High-resolution CT shows a vestibular aqueduct measuring 2.4 mm at the operculum with a cystic apical-middle turn confluence of the cochlea and a normal basal turn. What is the diagnosis?

   1. AMichel aplasia
   2. BCommon cavity malformation
   3. CIncomplete partition type II with an enlarged vestibular aqueduct
   4. DCochlear aplasia with a normal vestibule
   Show answer and explanation

   Correct answer: C. Incomplete partition type II with an enlarged vestibular aqueduct

   Incomplete partition type II (the Mondini deformity) comprises a normal basal turn with a cystic fused apical and middle turn, often with a dilated vestibule and an enlarged vestibular aqueduct (more than 1.0 mm at the midpoint or 2.0 mm at the operculum by the Cincinnati criteria), and typically produces fluctuating hearing loss provoked by minor trauma. Michel aplasia is complete labyrinthine agenesis and common cavity is a single undifferentiated cochleovestibular cavity, neither of which is present here. Cochlear aplasia implies an absent cochlea, which is inconsistent with the described turns.

   Reference: Sennaroglu L & Bajin MD, Classification of inner ear malformations, Journal of International Advanced Otology (2017); Vijayasekaran S et al., AJNR (2007)

6. Question 6 · Professionalism, Ethics, Law and Research Methodology

   Two radiologists independently assign BI-RADS categories to 200 mammograms. Raw percentage agreement is 88%, but the calculated Cohen kappa is 0.42. Which interpretation is correct?

   1. AAgreement beyond that expected by chance is only moderate, because much of the raw agreement is explained by the skewed distribution of categories
   2. BThe kappa value is invalid because raw agreement exceeds 80%
   3. CKappa of 0.42 indicates almost perfect agreement by conventional benchmarks
   4. DKappa measures the accuracy of the readers against pathology rather than their agreement
   Show answer and explanation

   Correct answer: A. Agreement beyond that expected by chance is only moderate, because much of the raw agreement is explained by the skewed distribution of categories

   Kappa corrects raw agreement for agreement expected by chance, and when one category dominates the distribution a high raw percentage agreement can coexist with only moderate kappa, which by the Landis and Koch benchmarks is 0.41 to 0.60. High raw agreement does not invalidate kappa, 0.42 is not almost perfect (that band is above 0.80), and kappa quantifies inter-observer agreement rather than accuracy against a reference standard.

   Reference: Landis JR, Koch GG. The measurement of observer agreement for categorical data, Biometrics, 1977; Kundel HL, Polansky M. Measurement of Observer Agreement, Radiology, 2003

7. Question 7 · Nuclear Medicine, Molecular and Hybrid Imaging

   A patient with a small bowel neuroendocrine tumour has both Ga-68 DOTATATE PET-CT and FDG PET-CT. The liver metastases are DOTATATE-negative but intensely FDG-avid. What does this mismatch most likely indicate?

   1. AA well-differentiated grade 1 tumour that will respond well to Lu-177 DOTATATE
   2. BDedifferentiated, higher-grade disease with loss of somatostatin receptor expression and a poorer prognosis
   3. CA technical failure of the DOTATATE synthesis
   4. DPhysiological hepatic uptake obscuring true DOTATATE-avid lesions
   Show answer and explanation

   Correct answer: B. Dedifferentiated, higher-grade disease with loss of somatostatin receptor expression and a poorer prognosis

   Loss of somatostatin receptor expression with high glycolytic activity (a 'flip-flop' or mismatch pattern) indicates dedifferentiation and higher-grade biology, predicting poorer outcome and unsuitability for peptide receptor radionuclide therapy. Grade 1 tumours are typically DOTATATE-avid and FDG-negative, and a synthesis failure would abolish uptake in normal spleen and adrenals as well, which is not described.

   Reference: ENETS Consensus Guidelines for standards of care in neuroendocrine tumours: radiological and nuclear medicine imaging (Sundin et al., Neuroendocrinology, 2017)

8. Question 8 · Neuro Imaging (Brain, Spine, Head Trauma and Neurovascular)

   Which parenchymal MRI pattern most strongly favours venous infarction over arterial infarction?

   1. AWedge-shaped cortical and subcortical lesion conforming to a single arterial territory
   2. BUniformly restricted diffusion throughout the lesion with low ADC values
   3. CBilateral parasagittal haemorrhagic lesions with extensive vasogenic oedema crossing arterial boundaries
   4. DLacunar lesion in the posterior limb of the internal capsule
   Show answer and explanation

   Correct answer: C. Bilateral parasagittal haemorrhagic lesions with extensive vasogenic oedema crossing arterial boundaries

   Venous infarcts arise from raised venous pressure rather than arterial occlusion, so they cross arterial territories, are frequently bilateral and parasagittal with superior sagittal sinus thrombosis, and characteristically show prominent vasogenic oedema with a high rate of petechial or frank haemorrhage. Arterial infarcts respect a defined arterial territory and show early, relatively uniform cytotoxic oedema with restricted diffusion. A lacunar lesion in the internal capsule reflects small vessel arterial disease, and both a single-territory wedge and a lacune argue against a venous cause.

   Reference: Saposnik G et al., AHA/ASA Scientific Statement: Diagnosis and Management of Cerebral Venous Thrombosis, Stroke 2011

9. Question 9 · Chest Imaging (Thoracic Radiology)

   A 52-year-old woman has 18 months of worsening dyspnoea. CT pulmonary angiography shows eccentric thrombus adherent to and forming obtuse angles with the arterial wall, intraluminal webs and bands, abrupt narrowing of segmental arteries, mosaic attenuation with vessel-calibre variation between regions, and dilated bronchial arteries. What is the most likely diagnosis?

   1. AAcute massive pulmonary embolism
   2. BChronic thromboembolic pulmonary hypertension
   3. CPulmonary artery sarcoma
   4. DFibrosing mediastinitis
   Show answer and explanation

   Correct answer: B. Chronic thromboembolic pulmonary hypertension

   Eccentric wall-adherent thrombus with obtuse angles, webs and bands, abrupt vessel cut-offs and post-stenotic dilatation, mosaic perfusion with differential vessel calibre, and hypertrophied systemic bronchial collaterals are the defining features of chronic thromboembolic pulmonary hypertension. Acute embolus is typically central within the lumen, forms acute angles with the wall and expands the vessel. Pulmonary artery sarcoma usually fills and expands the main pulmonary artery with enhancement and extraluminal extension, and fibrosing mediastinitis causes soft-tissue encasement of mediastinal structures, often with calcification.

   Reference: ESC/ERS Guidelines for the Diagnosis and Treatment of Pulmonary Hypertension (2022); Fleischner Society Statement on CTEPH imaging, Radiology (2021)

10. Question 10 · Contrast Media, Imaging Physics and Radiation Safety

    A CT pulmonary angiogram in a large patient shows poor opacification of the segmental pulmonary arteries. The scanner is a dual-energy system. Which post-processing step is most likely to salvage the study?

    1. AReconstruct virtual monoenergetic images at a low keV, such as 40-50 keV
    2. BReconstruct virtual monoenergetic images at a high keV, such as 140 keV
    3. CReconstruct virtual non-contrast images from the spectral dataset
    4. DReconstruct with a sharp (bone) kernel at standard tube potential
    Show answer and explanation

    Correct answer: A. Reconstruct virtual monoenergetic images at a low keV, such as 40-50 keV

    Low-keV virtual monoenergetic reconstructions sit close to the iodine K-edge (33.2 keV), so iodine attenuation and vascular contrast rise substantially, rescuing an underenhanced angiographic study (at the cost of increased image noise). High-keV images do the opposite, reducing iodine conspicuity while suppressing metal artefact; virtual non-contrast images deliberately subtract iodine; and a sharp kernel increases noise without improving vascular attenuation.

    Reference: McCollough CH et al., Dual- and Multi-Energy CT: Principles, Technical Approaches and Clinical Applications, Radiology, 2015

11. Question 11 · Cardiovascular Imaging

    Cardiac MRI is performed in a patient with an apical left ventricular filling defect after anterior myocardial infarction, to determine whether it is thrombus or tumour. Which sequence is most useful for making this distinction?

    1. AFirst-pass perfusion imaging alone, since thrombus enhances avidly in the arterial phase
    2. BT2-weighted STIR imaging, on which thrombus is uniformly high signal
    3. CEarly gadolinium enhancement imaging with a long inversion time of around 550-600 ms, on which avascular thrombus appears homogeneously black while vascularised tissue does not null
    4. DCine SSFP imaging alone, on which thrombus is always higher in signal than myocardium
    Show answer and explanation

    Correct answer: C. Early gadolinium enhancement imaging with a long inversion time of around 550-600 ms, on which avascular thrombus appears homogeneously black while vascularised tissue does not null

    Thrombus is avascular, so with a long inversion time it remains uniformly signal-void while perfused tumour or myocardium takes up contrast and appears bright, making this the most reliable discriminator. First-pass perfusion shows absent enhancement in thrombus, which is supportive but the long-TI technique is the accepted problem-solving sequence. T2 signal in thrombus is variable and depends on age, and cine SSFP alone cannot reliably separate mural thrombus from tumour or trabeculation.

    Reference: SCMR Standardized Cardiovascular Magnetic Resonance Imaging Protocols (Journal of Cardiovascular Magnetic Resonance, 2020)

12. Question 12 · Head and Neck Imaging

    Nine months after chemoradiotherapy for a laryngeal carcinoma, a surveillance MRI shows diffuse symmetric mucosal enhancement and thickening, retropharyngeal oedema and subcutaneous fat stranding, plus a new 12 mm focal nodular enhancing lesion at the primary site with markedly reduced ADC. How should this be interpreted?

    1. AAll findings represent expected post-radiotherapy change; routine surveillance
    2. BDiffuse changes are radiation sequelae and the focal nodular lesion with restricted diffusion is suspicious for recurrence (NI-RADS 3), warranting biopsy
    3. CThe findings are typical of chondroradionecrosis and warrant conservative management only
    4. DThe pattern indicates a second primary tumour and warrants immediate total laryngectomy
    Show answer and explanation

    Correct answer: B. Diffuse changes are radiation sequelae and the focal nodular lesion with restricted diffusion is suspicious for recurrence (NI-RADS 3), warranting biopsy

    Diffuse symmetric mucosal enhancement, retropharyngeal oedema and fat stranding are the expected sequelae of radiotherapy, whereas a new focal nodular enhancing mass with low ADC at the primary site is the hallmark of recurrence and corresponds to a NI-RADS 3 category, which mandates tissue sampling. Dismissing the nodule as post-treatment change risks missing salvageable recurrence. Chondroradionecrosis shows cartilage fragmentation, sclerosis and gas without a discrete enhancing nodule, and proceeding directly to laryngectomy without histological confirmation is inappropriate.

    Reference: Aiken AH et al., ACR Neck Imaging Reporting and Data System (NI-RADS) (2018); NCCN Head and Neck Cancers Guidelines (2024)

Diagnostic Radiology reference books and guidelines

Every question in this bank names the textbook or guideline its answer rests on. These are the sources our Diagnostic Radiology questions cite most often - the reading list to revise from alongside the bank.

Where your regulator publishes a reading list, use the editions it names. Exam questions are not taken from any one book.