Tag: edir holder

Neuroradiology #37

~ EDiR Holders ~ 1 Comment

Clinical Data

40-year-old female presents with acute severe headache at the emergency department.
The neurologist wants to rule out an intracranial haemorrhage and orders a CT brain.

Showing images CT without contrast

More images: MRI

What do you see?

What do you see?

CT shows
* low attenuating suprasellar lesion (fat density) with rim calcification.
* multiple scattered smaller similar subarachnoid lesions supra and infratentorial.
* enlarged supratentorial ventricles.

MRI shows
* the suprasellar lesion shows T1 heterogenous and T2-hyperintense signal,
* multiple scattered T1-hyperintense foci subarachnoid and intraventricular in the left frontal horn (arrows).
* no enhancement.
* no diffusion restriction (not shown).

What is the most likely diagnosis?

What is the most likely diagnosis?

Ruptured suprasellar dermoid cyst.

Ruptured intracranial dermoid cyst

Intracranial dermoid cysts are often incidental findings and most do not cause symptoms. Both dermoid and epidermoid cysts are ectodermal in origin and lined by stratified squamous epithelium. In addition, dermoid cysts contain epidermal appendages such as sebaceous glands which secrete sebum, an oily substance.

Symptoms occur due to mass effect or rupture. In case of rupture, dermoid material (sebum droplets) can leak into the subarachnoid space which can lead to chemical meningitis and cause symptoms such as headaches, seizures, and vasospasms.
CT shows
-hypoattenuating primary lesion (fat density due to sebum).
-typically, not exclusively, in midline location.
-sometimes rim calcification of the primary lesion.
-smaller similar hypoattenuating lesions in the subarachnoid space in case of rupture.

MRI shows
-generally T1-hyperintense signal (sebum).
-scattered T1-hyperintense droplets in the subarachnoid space and intraventricular. Fat-fluid level within the ventricles.
-variable T2 signal.
-generally no enhancement of the lesion. Leptomeningeal enhancement in case of chemical meningitis.

References

https://radiopaedia.org/articles/intracranial-dermoid-cyst-1

Neuroradiology #35

~ EDiR Holders ~ 1 Comment

What do you see in the following images?

Click here to see the answer

Polymicrogyria
Bilateral cortical thickening with numerous small gyri with signal characteristics similar to normal grey matter.
Dilated bilateral perivascular spaces in the subjacent white matter.

Head and Neck #13

~ EDiR Holders ~ Leave a comment

What do you see?

Labyrinthitis Ossificans

Ossification of the membranous labyrinth, high-density bone deposition involving all the cochlear turns.

This usually occurs as a complication of suppurative labyrinthitis, either due to otomastoiditis or meningitis. Other causes include trauma, autoimmune diseases, and surgery.

Emergency #36

~ EDiR Holders ~ 1 Comment

47-year-old female:

– Found EMV 3 after assault

What do you see?

Click here to see the answer

– Diagnosis: Diffuse subdural hematomas of multiple ages (convexities, parafalcine, tentorium) But more important:

– Diffuse swelling of gyri and edema with effacement of the CSF-containing spaces
– Diffuse loss of normal grey-white differentiation
– Decreased bilateral basal ganglia attenuation

– = Sequelae of traumatic brain injury (TBI) indicating hypoxic-ischemic injury, with poor prognostic outcome. Patient died several hours later

– Note: We do not see here the reversal sign (reversal of the normal CT attenuation of grey and white matter) or white cerebellum sign (diffuse oedema and hypoattenuation of the cerebral hemispheres with sparing of the cerebellum and brainstem, resulting in apparent high attenuation of the cerebellum and brainstem relative to the cerebral hemispheres)

Emergency #33

~ EDiR Holders ~ Leave a comment

83-year-old female:
– Acute loss of function right arm and leg
– Bleeding? Ischemia?

What is the most likely diagnosis?

Dense left medial cerebral artery with subtle obscuring of grey-white matter interface temporal operculum of insula; early ischemia.

CTA: Occlusion M1 Patient received IV thrombolysis and her symptoms improved

Musculoskeletal #17 – Long Case

~ EDiR Holders ~ Leave a comment

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

What do you see?

Click here to see the answer

– 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.

Head and Neck #4 – Flashcard

~ EDiR Holders ~ 1 Comment

CT – Coronal + C
CT – Axial + C
Where is the abnormality?​

Left side of the neck.

How can the abnormality be described?​

Multiple enlarged neck clustered lymph nodes, with some of them showing necrosis.

What is the differential diagnosis?

Infectious lymphadenitis: such as TB or pyogenic lymphadenitis.
Metastasis: particularly from head and neck malignancies.
Treated lymphoma or lymphoma in immune compromised patient.

What is the final diagnosis

TB lymphadenitis

Emergency #26 – Flashcard

~ EDiR Holders ~ 1 Comment

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

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

Click here to see the images
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