Exam Timer

Model Answers

Case 1

Case 1 Model Answer:

Metastatic breast cancer causing lymphangitis carcinomatosis

Findings and interpretation:

  • There is a large, solid soft tissue mass in the right breast with irregular margins, as well as skin thickening over the right breast.
  • There is generalised nodular thickening of the fissures and interlobular septae of the right lung, giving the picture of lymphangitis carcinomatosis.
  • There is mild pleural thickening in the right hemithorax with loculated right pleural effusions. There is also a left sided moderate pleural effusion.
  • There are significantly enlarged right axillary lymph nodes, showing irregular borders and loss of the fatty hilum. There is a large sub-carinal mediastinal lymph node, as well as smaller pre-tracheal lymph nodes.
  • There are multiple bony lesions, both lytic and sclerotic, in the thoracic and lumbar vertebrae as well as the ribs. Multi-level vertebral compression fractures are noted in the thoracic and lumbar spines.
  • There is a displaced pleural pigtail catheter with the loop lying within the posterior right chest wall.

Incidental findings:

  • There is a right adrenal lesion with low (<10HU) density, representing an adenoma.


The findings represent a locally invasive and metastatic breast cancer with spread to the lymphatic channels in the right lung causing lymphangitis carcinomatosis. There is also metastatic spread to the right axillary and mediastinal lymph nodes, the bony skeleton and the pleurae with likely malignant effusions.


Principal diagnosis:

Metastatic breast carcinoma causing lymphangitis carcinomatosis.


Differential diagnosis:

  • The lung findings may potentially represent unilateral pulmonary oedema; however, this is extremely unlikely in light of the other findings.



Alert referring physician of findings.

Recommend ultrasound guided biopsy of the breast mass for histological diagnosis if not already obtained; diagnostic pleural tap may be performed for cytology.

Refer for breast cancer MDT.  

Case 1 Your Answer:

No Answer Submitted

Case 2

Case 2 Model Answer:

Thoracic aortic dissection in a patient with Marfan’s syndrome

Findings and interpretation:

Non-contrast CT

  • There is high density material within the anterior mediastinum surrounding the ascending aorta, as well as in the pericardial sac; this indicates haemomediastinum and haemopericardium.
  • There is pectus carinatum deformity of the chest wall, as well as mild scoliosis of the thoracic spine.
  • There is bilateral basal subsegmental consolidation, greater on the left side; there are also bilateral apical bullae.

Post-contrast CT / CT aortogram:

  • The root of the aorta / sinuses of Valsalva are markedly dilated, indicating annulo-aortic ectasia. This continues into an aneurysm of the ascending aorta, which tapers into a normal aortic arch.


  • There is an intimal flap extending from the root of the aorta to the level of the mid-thoracic aorta; the right brachiocephalic artery arises from the false lumen.

Pertinent negative findings:

  • There is normal enhancement of the great vessels arising from the aortic arch.
  • There is no contrast extravasation into the mediastinum/ pseudo-aneurysm formation to indicate frank rupture.

The findings represent a Stanford A aortic aneurysm complicated by acute aortic dissection; this is causing bleeding into the mediastinum, suspicious for impending rupture. The musculoskeletal and pulmonary findings, as well as the patient’s age, suggest that there is an underlying connective tissue disease.


Principal Diagnosis:

Acute aortic dissection in a patient with Marfan’s syndrome.


Differential diagnosis:

  • Homocystinuria and Ehlers Danlos syndromes may also feature aneurysms and similar musculoskeletal findings.



Urgently inform referring physician of findings.

An urgent vascular surgery consultation is warranted.

Case 2 Your Answer:

No Answer Submitted

Case 3

Case 3 Model Answer:

Multi-system granulomatosis with polyangiitis (formerly known as Wegener’s disease)

Findings and interpretation:


  • There are two, thick-walled cavitating lesions in the right apex.
  • There is circumferential, polypoidal mucosal thickening in the maxillary sinuses bilaterally.

CT upper abdomen:

  • There are multiple bilateral hypodense/hypo-enhancing renal lesions of varying sizes.
  • The spleen is mildly enlarged.

Pertinent negative findings:

  • No thoracic/ abdominal lymphadenopathy.

Incidental findings:

  • There is a large nodule in the right lobe of the thyroid.


The bilateral solid masses in the kidney and cavitating nodules in the lungs each carry a differential, and the paranasal sinusitis may be an incidental finding; however, when combined the constellation of findings suggests a multisystem inflammatory disease rather than a neoplastic disease. The renal masses likely represent granulomatous renal pseudo-tumours and the cavitating nodules likely represent granulomatous nodules.


Principal diagnosis:

Multi-system granulomatosis with polyangiitis (formerly known as Wegener’s granulomatosis).


Differential diagnosis:

  • Multi-system tuberculosis
  • Disseminated metastases
  • Multi-system lymphoma



Alert referring physician of findings.

Recommend renal biopsy as further investigation.

Refer to rheumatology MDM to discuss correlation with lab test results such as c-ANCA.

Case 3 Your Answer:

No Answer Submitted

Case 4

Case 4 Model Answer:

Subacute osteomyelitis

Findings and interpretation:


  • There is a lucent lesion involving the distal metaphysis and epiphysis of the left tibia, appearing continuous across the growth plate. Periosteal reaction is noted at the distal tibia.


  • There is high T2/STIR signal involving the lower half of the left tibia and crossing the growth plate into the epiphysis, which corresponds with low signal on the T1 images; this indicates bone marrow oedema.
  • There is circumferential high signal around the cortex in the lower tibia, as well as elevation of the low signal periosteum off the cortex in the PD images, indicating periostitis.  
  • There is significant enhancement on the post contrast images at the distal tibial metaphysis and epiphysis, extending into the soft tissues around the cortex.
  • There is an irregular, serpiginous intramedullary lesion at the distal tibial metaphysis which shows high T2 signal, with some adjacent high T1 signal. On the post-contrast images, there is surrounding enhancement with no enhancement in the centre of the lesion.
  • There is a small focus of T2/STIR signal hyperintensity with corresponding low T1 signal at the mid-shaft of the right tibia.

Pertinent negative findings:

  • There is no soft tissue lesion.
  • There are no surrounding soft tissue abscesses.
  • There are no sinus tracts / cloaca extending through the cortex.
  • There is no involucrum / sequestrum.


The findings represent significant inflammation of the distal tibia, with an evolving abscess. The right tibial lesion has a non-specific appearance, and may represent a second focus of infection.


Principal Diagnosis:

Sub-acute osteomyelitis of the left distal tibia with evolving Brodie’s abscess.


Differential diagnosis:

  • Eosinophilic granuloma: this is unlikely as this entity does not cross the growth plate.



Alert referring physician of diagnosis.

Recommend orthopaedic referral and discussion at orthopaedic MDT.

Treatment is usually with IV antibiotics; drainage of the abscess may be required.

Case 4 Your Answer:

No Answer Submitted

Case 5

Case 5 Model Answer:

Superior sagittal sinus thrombosis with haemorrhagic venous infarcts


52 year old woman who presented with left upper limb weakness and seizures.


CT brain pre and post contrast


Findings and interpretation:

Non contrast CT:

  • There are bilateral hypo-attenuating brain parenchymal lesions involving the subcortical white matter and cortex of the right high frontal and left high parietal lobes. These show foci of hyper-attenuation matching that of blood density.
  • The lesions exhibit moderate mass effect with adjacent sulcal effacement.
  • There is linear inter-sulcal hyperdensity adjacent to the right sided lesion, representing minimal sub-arachnoid haemorrhage.

CT venography:

  • There is a filling defect extending through most of the superior sagittal sinus. This demonstrates an empty delta sign on the coronal images, with a triangular filling defect outlined by surrounding contrast.


The findings indicate bilateral parenchymal venous infarction, with cytotoxic oedema complicated by haemorrhagic transformation. This is caused by thrombosis of the superior sagittal sinus.


Principal Diagnosis:

Bilateral venous infarction caused by superior sagittal sinus thrombosis.


Differential diagnosis:

  • Haemorrhagic brain metastases with coincidental dural sinus thrombosis (extremely unlikely)



Urgently contact referring physician and inform of diagnosis.

Immediate administration of anticoagulation should be performed.

Case 5 Your Answer:

No Answer Submitted

Case 6

Case 6 Model Answer:


Findings and interpretation:


  • There is a heterogeneous solid mass of mixed echogenicity located in the retroperitoneum; it drapes across the spine and crosses the midline from right to left.


  • CT confirms the US findings of a large retroperitoneal mass.
  • The mass contains scattered, coarse punctate and curvilinear calcifications throughout.
  • The mass is intimately related to the spine and posterior abdominal wall. It is seen separate from both kidneys, and displaces the liver, pancreas, aorta and IVC anteriorly without invasion.
  • The mass is heterogeneously enhancing.

Pertinent negative findings:

  • There are no osseous / hepatic / pulmonary lesions to suggest distant metastasis.


The findings represent a malignant mass of neural origin, originating from the paraspinal ganglia.


Principal diagnosis:

Neuroblastoma (stage 3)


Differential diagnosis:

  • Ganglioneuroblastoma: usually seen in older children.
  • Wilm’s tumour: this is extremely unlikely as the mass does not arise from either kidney.



Alert referring physician of findings.

Recommend further investigation by 99Tc-MDP / 123MIBG to assess for bony metastases.

Discuss at paediatric oncology MDT.

Case 6 Your Answer:

No Answer Submitted
Checking RIA Helper presence
RIA Helper has not been found on this PC.

If the application has been already installed, please make sure it is running.
You can click here to try and start it now.

Otherwise please proceed by installing the RIA Helper.

What is RIA Helper?

RIA Helper is a software module improving your experience with NeoLogica's Rich Internet Applications (RIAs), including Java-based applications. It allows obtaining a smooth and uniform user experience across all web browsers and all operative systems.
Please click here to try to launch RemotEye Viewer anyway using Java Web Start