Findings and interpretation:

• There are bilateral, symmetrical small hypodense rounded areas in both thalami anteriorly.
• There is hypodensity of the midbrain and pons, extending into both cerebellar hemispheres. 
• There is hyperdensity of the basilar artery.

Pertinent negative findings:

• No evidence of haemorrhage in the hypodense regions of the brain.
• No evidence of venous sinus thrombosis.

There is a posterior circulation territory ischemic infarct involving the artery of Percheron, resulting in bilateral thalamic as well as midbrain, pons and cerebellar infarcts. This is caused by acute thrombosis of the basilar artery.

Principal Diagnosis:

Basilar artery thrombosis causing posterior circulation and artery of Percheron infarction.

Differential diagnosis:

Venous infarcts caused by venous sinus thrombosis; however, this appears as enlargement of the thalami with hyperdensity of the straight sinus.

Management:

Urgent neurological / neuro-interventional consult for the possibility of thrombectomy.

Findings and interpretation:

• The left ovary is massively enlarged with innumerable cysts dispersed throughout the ovary; it shows a distorted shape and has a component extending to the right side.
• The right ovary is enlarged, albeit to a much lesser extent, and contains two large cysts; there is encysted simple fluid around the right ovary.
• The T1 series show linear and crescentic foci of high signal intensity interspersed within and between the cysts of the left ovary mainly, representing haemorrhage.
• The post contrast series demonstrate avid enhancement of the follicle walls and ovarian stroma.

Pertinent negative findings:

• There is no evidence of ovarian torsion.

Incidental findings:

• There is a large mass in the posterior wall of the uterus showing low SI on both T1 and T2 series, with differential post contrast enhancement, representing an intramural fibroid.
• There are multiple simple cysts within the cervix, representing Nabothian cysts.

The features indicate stimulation of the ovaries by fertility medication, which was complicated by haemorrhage. There is also a peritoneal inclusion cyst around the right ovary.

Principal diagnosis:

Asymmetric / atypical ovarian hyperstimulation syndrome complicated by haemorrhage.

Differential diagnosis:

• Ovarian cystic neoplasm; however this does not typically show innumerable cysts, which indicate hyperstimulation.

Management:

Alert referring physician of findings and suspicion, and ask if the patient had received any fertility treatments / fertility medication such as gonadotropins and HCG.

Recommend gynaecological referral.

Findings and interpretation:

CT:

• There is a well circumscribed soft tissue mass in the posterior triangle of the neck, adjacent to the upper cervical vertebrae. It is causing displacement of the adjacent muscles.

MRI:

• The soft tissue mass is heterogeneously hyperintense on the T2 images. The mass is less well defined on the MRI study, with spread of T2 signal into the adjacent trapezius muscle.
• The mass shows ill-defined, heterogeneous contrast enhancement which appears to extend into the surrounding tissues.

Pertinent negative findings:

• There are no suspicious / enlarged cervical lymph nodes.
• The adjacent bone shows no periosteal reaction or involvement by the mass.

The findings represent an aggressive soft tissue neoplasm.

Principal diagnosis:

Soft tissue sarcoma

Differential diagnosis:

• Extra-osseous Ewing’s sarcoma
• Malignant peripheral nerve sheath tumour
• Benign nerve sheath tumour (this is less likely because of aggressive features)

Management:

Alert referring physician of findings.

Recommend staging CT thorax abdomen pelvis if not already performed.

Refer for sarcoma MDT to discuss biopsy in conjunction with orthopaedic surgeons / referral to tertiary sarcoma centre.

Findings and interpretation:

CT brain:

• There is hypo-attenuation and sulcal effacement of the right temporal lobe (particularly in the medial aspect), as well as the insular cortex.

MRI brain:

• There is T2 and FLAIR hyperintensity of the medial aspects of the temporal lobes bilaterally (greater on the right side), as well as the right insular cortex and cingulate gyrus.

Pertinent negative findings:

• There is no diffusion restriction or contrast enhancement of the involved regions of the brain parenchyma.
• No evidence of haemorrhage within the lesion.

The findings represent bilateral yet asymmetrical oedema / inflammation of the limbic system.

Principal diagnosis:

Herpes simplex encephalitis

Differential diagnosis:

• Limbic encephalitis (paraneoplastic. No known primary and typically longer history)
• Post status epilepticus transient brain changes (no history of seizure)
• Gliomatosis cerebri (typically involves basal ganglia, which are spared by HSV encephalitis)

Management:

Urgently contact treating physician to inform of findings and recommend prompt antiviral treatment.

Findings and interpretation:

• There is a large, heterogeneously T2 hyperintense abdominal mass arising from the liver.
• The mass shows avid peripheral enhancement on the arterial phase post-contrast images.
• There is gradual filling in of contrast enhancement on the delayed images, with a persistent large non-enhancing centre.

Pertinent negative findings:

• There are no calcifications in the lesion.

The findings likely represent a benign vascular neoplasm.

Principal diagnosis:

Infantile hepatic haemangioma

Differential diagnosis:

• Hepatoblastoma

Management:

Alert referring physician of findings.

Recommend testing for serum alpha-fetoprotein (which is raised in hepatoblastoma).

Refer to paediatric surgery MDT for discussion regarding further management. Image guided biopsy is indicated to rule out hepatoblastoma. If the child remains asymptomatic, then follow up imaging is advised, as these tumours undergo natural involution. In case of high output cardiac failure, endovascular embolisation may be indicated.

Findings and interpretation:

• There is a large, irregular area of consolidation in the right upper lobe.
• There is generalised nodular thickening of the fissures and interlobular septae of both lungs.
• There are widespread semi-solid nodular opacities throughout both lungs.
• There is bilateral perihilar lymphadenopathy and minimal pleural effusions.
• There is a small peripheral aneurysm in the pulmonary arterial tree in the right lower lobe.

Pertinent negative findings:

• No adrenal lesions.
• No suspicious bony lesions.

Both lungs are involved in a likely malignant process arising from the right upper lobe.

Principal diagnosis:

Invasive mucinous adenocarcinoma in the right upper lobe, giving rise to lymphangitis carcinomatosis involving both lungs.

Differential diagnosis:

• Sarcoidosis
• Kaposi’s sarcoma (no history of HIV positive status; finding of large consolidation is unusual for this diagnosis)

Management:

Alert referring physician of findings.

Refer for pulmonary MDT to recommend image guided biopsy of right upper lobe consolidation, and obtain staging CT of the abdomen and pelvis.