Exam Timer

Model Answers

Case 1

Case 1 Model Answer:

Findings and interpretation:

Radiograph at one week:

  • The venous line is misplaced with the tip lying in an intrahepatic location within the portal venous system. The umbilical arterial catheter is in adequate position at T8. The endotracheal tube is in adequate position.
  • The lungs are diffusely opaque with linear and cystic lucencies radiating peripherally from both hila.

Radiographs at two weeks:

  • There are round and curvilinear air densities along bowel walls, indicating pneumatosis intestinalis.
  • On the lateral decubitus film, there is air density outlining the right border of the liver. The falciform ligament is outlined on both sides by air density.
  • The appearance of the lungs is unchanged.

 

The initial radiograph shows air within the pulmonary interstitium and lymphatics, as a result of barotrauma following mechanical ventilation in an infant with respiratory distress syndrome.

The following radiographs show the development of necrotizing enterocolitis and perforation of the bowel with pneumoperitoneum.

 

Diagnoses:

Misplaced venous line

Respiratory distress syndrome complicated by pulmonary interstitial emphysema

Necrotizing enterocolitis complicated by perforation and pneumoperitoneum

 

Differential diagnosis:

None

 

Management:

After the initial radiograph is reviewed, the venous line should be re-positioned in the first instance. The referring physician should then be alerted about the respiratory complication. The later radiographs show a surgical emergency. This warrants an urgent paediatric surgeon referral for operative treatment.

Case 1 Your Answer:

No Answer Submitted

Case 2

Case 2 Model Answer:

Findings and interpretation:

  • There is a hyperdense fluid collection in the retroperitoneal space, centred at the right adrenal gland, and infiltrating down to the perirenal fat, as well as the posterior and anterior pararenal spaces.
  • The hyperdense fluid is also seen in the pelvis and left iliac fossa, and is extending into a fat containing left inguinal hernia.
  • There is a partially calcified mass in the right adrenal gland. On the post-contrast images, the mass shows avid, heterogeneous arterial phase enhancement.
  • There is no contrast extravasation.
  • There is a well defined, hyperenhancing soft tissue mass within the left adrenal gland.
  • There is bilateral basal lung atelectasis with associated pleural effusions.

 

The findings represent haemorrhage from a right adrenal neoplasm. The left sided adrenal lesion represents a synchronous hypermetabolic neoplasm.  

 

Principal diagnosis:

Bilateral phaeochromocytoma, with recent haemorrhage from the one on the right

 

Differential diagnosis:

  • Adrenocortical carcinoma (these are more likely to be large and less likely to bleed; this would be unilateral)
  • Adrenal metastases (these do not typically bleed and are not usually hypervascular)

 

Management:

Urgently contact referring physician and inform of findings.

Recommend endovascular embolization if clinically warranted.

After management of bleeding, recommend correlation with serum and urinary catecholamines at MDT.

 

Case 2 Your Answer:

No Answer Submitted

Case 3

Case 3 Model Answer:

Sickle cell anaemia

Findings and interpretation:

Radiographs:

  • All thoracic spine vertebrae have a biconcave shape, indicating collapse of the central endplates caused by avascular necrosis.
  • There is flattening, cortical irregularity and sclerosis of the right femoral head, giving a coxa magna deformity appearance with secondary degenerative right hip joint change. This represents chronic avascular necrosis.
  • The left femoral head shows a milder degree of flattening and sclerosis.

MRI thighs:

  • High STIR and low T1 marrow signal demonstrated in the femoral heads, as well as the proximal right femur, indicating marrow oedema. High STIR signal in the right hip joint indicates a small effusion.
  • Patchy serpiginous low and high STIR signal seen in the right proximal and mid femur, and the left mid and distal femur, indicating osteonecrosis / bone infarcts.
  • High STIR signal surrounds the periosteum of the right femur, indicating acute infarction.

MRI abdomen:

  • The spleen is shrunken and markedly hypointense on T2, reflecting splenic auto-infarction.
  • There are hypointense, aggregated dependent objects in the gallbladder lumen, representing gallstones / sludge.
  • Mixed high and low T2 signal lesions are visualised in the thoracic vertebral bodies, indicating osteonecrosis.

 

The constellation of findings are characteristic of sickle cell anaemia, with acute right femoral infarction.  

 

Principal diagnosis:

Sickle cell anaemia.

 

Differential diagnosis:

None.

 

Management:

Alert referring physician of findings.

Refer for haematology MDM to discuss further management / treatment options.

Case 3 Your Answer:

No Answer Submitted

Case 4

Case 4 Model Answer:

Findings and interpretation:

  • There are conglomerate peritoneal masses with fluid anteriorly and at the flanks, as well as perihepatic and perisplenic fluid. There is omental caking. There is scalloping of the liver margins.
  • There is a large polypoidal mass in the caecum which invaginates into the ascending colon along with the terminal ileum, with the mesenteric vessels and fat seen within the colonic lumen.
  • There are multiple enlarged peri-cecal lymph nodes, which show loss of the normal reniform shape and demonstrate peripheral enhancement.
  • The appendix is enlarged, measuring 1.1cm in calibre with enhancing walls.

 

Pertinent negative findings:

  • There are no hepatic parenchymal metastases / suspicious bony lesions / metastases in the lung bases.

 

The findings represent a primary mucinous malignancy in the caecum, which has caused ileo-colic intussusception. This shows local metastatic spread to adjacent draining lymph nodes. The peritoneal findings represent peritoneal carcinomatosis with pseudomyxoma peritoneii. The appendix shows evidence of inflammation, likely secondary to obstruction from the adjacent mass.

 

Principal diagnosis:

Intussuscepted mucinous adenocarcinoma of the caecum with peritoneal metastatic spread and secondary appendicitis.

 

Differential diagnosis:

  • Adenocarcinoma of the terminal ileum.
  • Adenocarcinoma of the appendix: however, there is greater thickening of the cecal wall.

 

Management:

Alert referring physician of findings.

Refer for oncology / general surgery MDT discussion to discuss further imaging (staging CT thorax), as well as image guided biopsy of peritoneal masses.

Case 4 Your Answer:

No Answer Submitted

Case 5

Case 5 Model Answer:

Findings and interpretation:

  • There are diffusely distributed patches of white matter hyperintensity located in the periventricular and subcortical white matter as well as the centrum semiovale, becoming confluent in certain areas. This represents leukoaraiosis.
  • There is generalised brain atrophy which is consistent with the age of the patient.
  • There are small, round and punctate areas of hypointense blooming artefact on the susceptibility weighted images, which are mostly seen in the cortical and subcortical regions of both cerebral hemispheres. There is relative sparing of the basal ganglia and brainstem.

Pertinent negative findings:

  • No cerebral amyloidoma.
  • There are no large lobar haemorrhages.

Incidental findings:

  • There is mucosal thickening of the maxillary sinuses, which may represent chronic sinusitis.
  • Virchow-Robin spaces visualised in the basal ganglia.

 

The findings represent ischemic leukoencephalopathy, and diffuse cerebral microhaemorrhages.

 

Principal diagnosis:

Cerebral amyloid angiopathy

 

Differential diagnosis:

  • Hypertensive microangiopathy: in this case, the micro-haemorrhages would show a predilection for the basal ganglia, brainstem and cerebellum
  • Multiple cavernoma syndrome
  • Diffuse axonal injury: this is associated with trauma and does not fit the clinical picture

 

Management:

Recommend neurological consult.

Case 5 Your Answer:

No Answer Submitted

Case 6

Case 6 Model Answer:

Findings and interpretation:

Ultrasound testes

  • The right testis is enlarged with lobulated contours, and appears heterogeneously hyperechoic.
  • The left testis is normal.

CT abdomen pelvis:

  • There is a large, irregular soft tissue mass in the retroperitoneum. It involves and displaces the IVC, extends into the right kidney, and encases the right renal artery. It shows heterogeneous post-contrast enhancement.
  • There is a smaller, more well defined, separate posterior mediastinal soft tissue mass with similar characteristics.
  • Invasion into the IVC is causing tumour thrombosis of the infrarenal IVC, which extends into the iliac and femoral veins with possible further peripheral extension.

Pertinent negative findings:

  • No pulmonary metastases.
  • No extension of tumour thrombus/ embolism into the pulmonary arteries.

 

The findings represent malignant retroperitoneal and posterior mediastinal masses / lymphadenopathy. This is invading the infrarenal IVC.

The ultrasound examination shows a malignant right testicular mass.

 

Principal diagnosis:

Testicular cancer with metastatic spread to the retroperitoneal and posterior mediastinal lymph nodes

 

Differential diagnosis:

  • Lymphoma which has spread to involve the right testis (however, testicular involvement by lymphoma is usually bilateral)

 

Management:

Alert referring physician of findings.

Refer to oncology MDT to discuss image guided biopsy of soft tissue mass / excisional biopsy of right testis, followed by treatment with chemotherapy.

 

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
Checking RemotEye Viewer presence
RemotEye Viewer 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 RemotEye Viewer.