Emergency #27 – Flashcard

Elbow pain after a fall. What do you see?

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Findings

Large joint effusion with the displacement of the anterior fat pad. Mild posterior soft tissue swelling over the olecranon. Fracture line along the lateral aspect of the radial neck. Radial head and articular surface are normal

Diagnosis

Nondisplaced radial head fracture

Teaching points

– Check not only the bones and joints but also the soft tissues
– Search and interpret the findings in two different positions
– Pain always withholds a story behind

Musculoskeletal #17 – Long Case

2-year-old girl, referring to emergency department after a fall.

What do you see?

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– An expansile lytic lesion with ill-defined margins (green arrow) is seen on the diaphysis of fibula.

– Lamellated periosteal reaction (red arrow) suggests an aggressive lesion.

Differential diagnosis of an aggressive lytic lesion in a 2-year-old child includes:
– Osteomyelitis
– Ewing’s sarcoma
– Langerhans cell histiocytosis
– Leukemia/lymphoma

What should be done next?

An MRI scan

Intramedullary hyperintense lesion with extensive surrounding soft tissue and bone marrow edema on coronal STIR image (a) is seen. The lesion is hypointense on T1 WI (b).

Cortical destruction is shown on axial PD image (arrow in c).

Postcontrast coronal (a) and axial fat-suppressed (b) T1-weighted images show extensive enhancement in the lesion and the surrounding soft tissue

Histopathologic examination revealed Langerhans cell histiocytosis.

Langerhans Cell Histiocytosis (LCH)

– LCH is characterised by idiopathic infiltration and accumulation of abnormal histiocytes within various tissues.

– Bone is the most commonly affected tissue in children, with a predilection for axial bones, and femur is the most commonly affected long bone.

– Radiographic appearance of the lesions depends on the site of involvement and the phase of the disease.

Skull: Calvarium is more affected than the skull base, typically seen as single or multiple well-defined lytic lesions on radiography; T1 hypointense, T2 hyperintense with significant enhancement on MRI. Temporal bone is the most common affected part of skull base seen as destructive lesions with a soft tissue component.
Spine: Vertebral bodies are affected with relative sparing of posterior elements. A typical vertebra plana appearance may be encountered with total collapse.
Long bones: Ill-defined lytic lesions with/without cortical destruction are seen usually located at diaphysis or metaphysis. Periosteal reaction may be present. Extensive bone marrow and soft tissue signal changes on MRI may also be helpful in the diagnosis.

Emergency #26 – Flashcard

A 30-year-old female with right shoulder pain.

4 images of the right shoulder were obtained (axillar, Y-view, internal rotation, external rotation)

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Y-view

Internal rotation
External rotation
Findings:

Findings


Right shoulder: There is a nondisplaced fracture involving the inferior aspect of the glenoid, with involvement of the articular surface. Glenohumeral joint shows normal alignment. Acromioclavicular joint is normal. No soft-tissue calcification. No fracture or dislocation

What is the most likely diagnosis?

The most likely diagnosis is Hill-Sachs lesion

Hill-Sachs lesions are a posterolateral humeral head compression fracture. Typically occurs secondary to recurrent anterior shoulder dislocations. It is often associated with a Bankart lesion of the glenoid

Internal Rotation
External Rotation

These lesions are best seen following relocation of the joint. It appears as a sclerotic line running vertically from the top of the humeral head towards the shaft. A wedge defect may be evident in large lesions. The lesions are better appreciated on internal rotation views

Emergency #24 – Flashcard

A 43-year-old man with inflammation and lower abdominal pain:

What do you see?

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* Inflammatory wall thickening of the sigmoid colon.
* Multiple diverticula, but one enlarged with thickened enhancing wall (arrow).
* Surrounding haziness of the mesosigmoid fat.
* Peritoneal accentuation

Typical image of diverticulitis, in a typical location with typical presentation

Teaching point

Look for signs of perforation or abscess formation

Emergency #22 – Long case

81-year-old male:

* Severe pain abdomen
* Tender abdomen
* Clinical ileus

What do you see?

Diagnosis

Mechanical ileus with caliber change in ileum. Distended stomach with air in the major curvature of the wall, with air bubble outside lumen, suspect for pneumatosis intestinalis. Extended air in left portal vein branches and in central portal vein (portal venous gas peripheral, gas in bile ducts central).

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What additional findings do you see?

1. Contained rupture AAA with slowly progressive lytic destruction and remodeling of lumbar spine
2. Gall stones

Emergency #21 – Long case

A 21-year-old male:
* Collapse twice
* Loss of strength of right arm
* Trouble finding words
* Headache

What are the CT Findings?

CT Findings

* No abnormalities were seen.
* No bleeding.
* No signs of recent ischemia.

Patient develops fever. Cannot bend his neck properly. When asked, he has been traveling recently to Thailand

What further imaging could help us?

What are the MRI findings?

MRI findings

* Two areas left frontal and left parietal with T2/FLAIR hyperintense swelling/edema of cortex and subcortical white matter, with diffusion restriction and patchy, gyriform cortical enhancement
* Diffusely leptomeningeal enhancement
* No ring-enhancing lesions. No white matter vasogenic or cytotoxic edema

What is the most likely diagnosis?

Diganosis

Cerebritis (precursor of abscess) and meningitis. Not yet an abscess

Note: Encephalitis means inflammation of PARENCHYMA

Differential diagnosis of meningitis:
* Leptomeningeal carcinomatosis
* Sarcoidosis and other granulomatous diseases
* Vasculitis
* Connective tissue diseases

Viral inflammatory cause for symptoms was confirmed with lumbar puncture and patient was treated with IV anti-viral treatment.