Neuroradiology #27

48-year-old male patient, HIV (+); presented to emergency with headache, confusion, N/V.

What do you see?

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T2 hyperintense lesions of left caudate nucleus, left putaminal and right dentate nucleus , with perilesional edema.

Small corticomedullary T2 hyperintense lesions with faint enhancement.

Caudate and putaminal lesions demonstrates faint peripheric contrast enhancement whereas cerebeller lesion has strong peripheric and central nodular enhancement.

Caudate and cerebellar lesion have tiny microhemorrhages on SWI, a clue for diagnosis.


· Most common opportunistic CNS infection and most common cause of a mass lesion in AIDS
· Basal ganglia, thalamus, corticomedullary junction and cerebellum frequently involved
· Microhemorrhages can be seen on SWI, lesions may have ring or nodular enhancement
· Major ddx is lymphoma:
– Lymphoma is usually solitary whereas solitary lesions are uncommon in toxoplasmosis.
– Microhemorrhages are uncommon in lymphoma

Neuroradiology #26 – Long case

Where is the abnormality?

Right temporal lobe

What is it like?

Effacement of the temporal horn of the right lateral ventricle and subtle hypodensity within the right temporal lobe

What would you do next?

CT with contrast and MRI

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What are the MRI signal characteristics?

High-signal intensity lesion on FLAIR with significant edema and mass effect. Ring enhancement on post-contrast images

Neuroradiology #24 – Flashcard

89-year-old female patient with aplastic anemia. Showing CT images without contrast media. What do you see?

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CT images without contrast media: Subacute isodense right subdural hematoma, revealed with narrowing of right cerebral hemispheric sulci and right lateral ventricle and minimal midline shift (red arrows), acute left subdural hematoma (blue arrow)

Neuroradiology #22 – Flashcard

What do you see on these images?

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CT scan shows a large calcified lesion. MRI shows a large cortical-based high T2 lesion with cystic component and dark T2 foci corresponding to the calcifications. Post-contrast images show patchy enhancing areas.  

Differential Diagnosis

DNET (usually may calcify) ganglioglioma (cystic areas, enhancing solid component, may calcify).