Tag: EDiR

Neuroradiology #37

~ EDiR Holders ~ Leave a 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

Head and Neck #15

~ EDiR Holders ~ Leave a comment

What do you see in the following images?

Click here to see the answer

Scalp haemangioma
Right parietal subcutaneous well-defined soft tissue oval lesion. It demonstrates low signal on T1W image, Intermediate signal on T2W image with prominent vascular flow voids, and avid enhancement on the post contrast image. No adjacent osseous or soft tissue abnormality. No intracranial extension.

More information

Infantile hemangiomas are benign vascular tumours, most of these tumours arise in the craniofacial region. Most of them are not present at birth but they increase in size during the first year of life, with a subsequent progressive involution during early childhood.

Differential diagnosis includes: epidermoid cyst, lymphatic malformation,  and sinus pericranii.

Abdominal #22

~ EDiR Holders ~ Leave a comment

45-year-old female patient:

* Generally unwell with abdominal pain and palpable cervical lymph nodes

Clinical information:

– Newly diagnosed HIV infection with a very low CD4 count of 30 cells/uL
– Generally unwell
– Presents at the emergency department with abdominal pain and palpable cervical lymph nodes

What do you see?

Diagnosis:

Most likely pulmonary and extrapulmonary tuberculosis in an immunocompromised patient with miliary pulmonary lesions, tuberculous colitis and ileitis, and necrotic extrapulmonary adenopathy (cervical and abdominal adenitis)
Microbiological analysis of an excised abdominal node confirmed the presence of Mycobacterium tuberculosis

Treatment:

Ileocaecal resection, tuberculostatic medication, and HAART

Teaching points:

– Be aware of TB in immunocompromised patients
– Cervical nodes are the #1 site of extrapulmonary TB adenopathy and the most common cause of adenopathy worldwide
– Intestinal tuberculosis can mimic inflammatory bowel disease

Abdominal #21

~ EDiR Holders ~ Leave a comment

86-year-old patient:

– With sudden collapse

Clinical information:

– Patient known with infrarenal aortic aneurysm
– Sudden collapse at home
– Transfer to the hospital with ambulance

Axial and coronal slices of an abdominal CT in 2019 show a tortuous abdominal aorta with aneurysmal dilatations and eccentric thrombus. There is a thrombosed saccular component at the level of the aortic bifurcation (arrow)

CT at presentation:

What is the diagnosis?

Diagnosis:

– Ruptured aortic aneurysm
* known infrarenal aortic aneurysm
* massive retroperitoneal hematoma extending into the posterior pararenal and perirenal compartments
* active contrast extravasation
– Point of weakness: saccular aneurysmal component

Teaching points:

– This case did not show a classic sign of pending rupture; however, a clear point of weakness was retrospectively identified (the saccular aneurysmal component at the aortic bifurcation)
– Radiological signs of pending rupture:
* !! High attenuating crescent (= acute haematoma within the mural thrombus or aneurysmal wall)
* Focal discontinuity of intimal calcification and ‘tangential calcium sign’
* ‘Draped aorta sign’, present when
* The posterior aortic wall is unidentifiable as a distinct line
* The posterior aorta follows the contour of the spine on one or both sides
– Reference: CT signs of pending aortic aneurysm rupture, J.P. Heiken, radiologyassistant.nl
https://radiologyassistant.nl/abdomen/aorta/aneurysm-rupture

Head and Neck #14

~ EDiR Holders ~ Leave a comment

What do you see in the following images?

Click here to see the answer

Nasolabial cyst
Right nasolabial lesion with remodeling of the maxillary alveolus bone. On MRI it shows high signal intensity on both T1- and T2-weighted images with no signal suppression on the T2 FLAIR with Fat saturation sequence.
Differential Diagnosis:
Nasolabial cyst with hemorrhage
Epidermal inclusion cyst
Dermoid cyst
Dentigerous cyst

Abdominal #20

~ EDiR Holders ~ Leave a comment

61-year-old female:
– With elevated ALT, AST, and bilirubin

What do you see?

What do you see?

Wall thickening and enhancement of the gallbladder wall
Mild common bile and intrahepatic duct dilatation
Filling defect within the distal common bile duct

Diagnosis:

Choledocholithiasis

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.

Musculoskeletal #27

~ EDiR Holders ~ Leave a comment

53-year-old female:

– Chronic sensory polyneuropathy (autoimmune). Long-term corticosteroid therapy.
– Forefoot pain for three weeks (acute onset without trauma).
– Physical examination: no haematoma , mild swelling.
– X-ray performed on day 2 after initial pain.
– MRI performed on day 25 after initial pain.

What are the findings?

X-Ray: No obvious fracture.

MRI:
– Bone marrow heterogeneous oedema within the third metatarsal diaphysis (hypointense on T1W image, hyperintense on Proton Density (PD) FatSat image).
– Linear low signal intensity fracture identified in all sequences.
– Periosteal reaction due to callus formation. Periosteal thickening and enhancement (contrast administration is not necessary for diagnosis).
– Surrounding soft-tissue oedema (adjacent fat and interosseous muscles).

Metatarsal stress fracture (“march fracture”)

– Stress fractures are caused by overuse and repetitive activity.
– Everyday activities may result in a stress fracture if there is any disease or therapy that weakens the bone such as osteoporosis or long-term use of steroids (bone insufficiency: long-term treatment with steroids in this case).
– Classically affects the 2nd or 3rd metatarsal of the foot “march fracture”: named after its prevalence in soldiers who often undertake repeated and prolonged periods of walking as part of their training or work.
– Bone changes are usually not evident on X-rays before 10 to 21 days following the injury. May not be visible for several weeks later, until callus bone formation (the sensitivity range, for detecting stress fractures on initial examinations, is 15-35%; it increases to 30-70% at follow-up studies due to bone reaction).

MRI findings:
– The fluid-sensitive sequences (T2-weighted images with chemically selective fat suppression or STIR sequences) are very useful for the detection of the earliest changes of stress reaction, such as periosteal reaction, muscle, or bone marrow oedema.
– T1-weighted sequences depict the anatomy and more advanced stress-related findings.

Grading based on MRI (Arendt and Griffiths)🙂
1: Mild – moderate periosteal oedema on STIR, no marrow changes.
2: Moderate – severe periosteal oedema on STIR + marrow changes on T2-weighted.
3: Grade 2+ marrow changes on T1-weighted.
4: Fracture line visible.

Head and Neck #12

~ EDiR Holders ~ Leave a comment

24-year-old male:
– Feels a lump in the upper lateral corner of right eye.
– MRI was made.

What do you see?

Preseptal lesion right supero-lateral corner, lateral to lacrimal gland.
T2 and T1 hyperintense, low signal after fat suppression.
No enhancement (right upper picture).
Slight remodeling of bone.
No invasive growth no post-septal component.

What is the most likely diagnosis?

Diagnosis: dermoid cyst, also fits with age and location of lesion.