Neuroradiology #34

54-year-old woman:
– Known breast cancer
– Arm paresis and soft-tissue lump

What are the salient findings?

Left: NECT, bone algorithm. Aggressive-like bone lesion with permeative pattern and hair on end periosteal reaction

Right: MRI T1 post-Gd. Associated trans-diploic soft-tissue mass with extracranial and intracranial-extraaxial components. Solid, homogeneous and avidly enhancing. Contiguous dural thickening and enhancement.

What is the differential diagnosis?
DIFFERENTIAL DIAGNOSIS FOR TRANS-DIPLOIC SKULL VAULT LESION WITH AGGRESSIVE-LIKE BONE AFFECTATION

1- Metastasis
2 – Myeloma/Plasmocytoma
3 – Lymphoma
4 – Primary Bone Tumour (Osteosarcoma)
5 – Dural Lesion (Meningioma+++, Hemangiopericytoma)

METASTASES
METASTASES

– Always consider in older patients
– Multiplicity and known primary

Imaging
Varies depending on tumor type and aggressiveness

– Lytic: Most tumor types
– Permeative: Highly cellular and small-round cell tumors (PNET, small cell lung, lymphoma)
– Sclerotic/mixed: Prostate, breast. Less frequently: Transitional cell, neuroendocrine, PNET
– Hypervascular: Renal cell, melanoma, thyroid, hepatocarcinoma, lung, neuroendocrine

Possible soft-tissue components

LYTIC AGGRESSIVE BONE LESION/S IN PATIENT >40 years old. METASTASES vs MYELOMA

MULTIPLE MYELOMA (MM)/SOLITARY PLASMOCYTOMA
MULTIPLE MYELOMA (MM)/SOLITARY PLASMOCYTOMA

– Affects older patients (median 68-70 years). Very rare under 40 years (<10%) Imaging
MM 4 patterns of bone involvement
– Diffuse lytic bone infiltration simulating osteopenia
– Multiple focal lytic well-defined lesions
– Solitary plasmacytoma
– Sclerotic bone lesions (exclusively associated with POEMS sd)

Solitary plasmacytoma in the skull: lytic, aggressive trans-diploic, soft tissues, and hypervascular aspect

CLASSIC APPEARANCE OF MM
CLASSIC APPEARANCE OF SOLITARY PLASMOCYTOMA OF THE SKULL
LYMPHOMA
LYMPHOMA

– 7% of all bone malignancy; 5% of extranodal lymphoma
– All ages; predominates in adults (peak 50-60 years); men/women 1.5:1
– Secondary dissemination >>> primary bone lymphoma
– Imaging characteristics of a hypercellular small round cell tumour

Imaging
– Trans-diploic permeative bone pattern and abundant of tissue components (small round blue cells spread through Haversian canals conditioning a striking relatively little bone destruction in comparison to important soft-tissue lesions)
Hyperdensity on NECT, T2 hypodensity and striking diffusion restriction on DWI (all signs related to hypercellularity)
– Homogenous enhancement
– No or little necrosis

CHARACTERISTIC IMAGING FINDINGS FOR LYMPHOMA
OSTEOSARCOMA
OSTEOSARCOMA

– Most common primary high-grade bone sarcoma
– Bimodal distribution: 10-14 and >40 years old
Extremely rare in the skull in adults, and much more frequently arising from coexisting Paget’s disease> >previously irradiated bone> or bone infarction
– Clinically, quickly growing painful mass

Imaging
– Destructive, aggressive lesion, with periosteal reaction, soft tissue-mixed lytic-blastic component. May show “fluffy”, “cloud-like” osteoid matrix.

Secondary osteosarcoma arising in a Pagetic skull. See the globally aggressive pattern and the deep hypointensities inside the soft-tissue components probably transducing osteoid matrix (usually easily depicted on CT, non-available in this case)

MENINGIOMA
MENINGIOMA

– Most common brain tumor (36% of all brain tumors)
– Predilection for middle-aged females
– Can produce neurologic symptoms due to compression
– Most do not infiltrate bone, but when they do it, the hyperostosis is very specific, virtually pathognomonic
– Intra-diploic or trans-diploic meningiomas are less frequent

Imaging
Key signs:
Calcifications
“Dural tail” and extra-axial semiology
Hyperostosis (very specific)
– Hypervascular with intense homogenous enhancement

*Even the great specificity of the hyperostosis, bone involvement can be VERY VARIABLE including aggressive-like lysis and periosteal reactions that do not exclude or go against the diagnostic

Ddx: Hemangiopericytoma (Solitary Fibrous Tumor New WHO 2016 classification). Younger, frequently male patients. Osteolysis possible, but NO hyperostosis. NO calcifications. The rest of imaging features identical to meningioma, differentiation is very difficult and challenging

EXAMPLES OF THE MULTIPLE FACES OF MENINGIOMAS AND THEIR BONE INVOLVEMENT. REMEMBER, POLYMORPHISM IS AN IMPORTANT FEATURE OF THIS ENTITY

With all the information mentioned above:

Could meningiomas condition aggress periosteal reaction? Does it go against its diagnosis

Meningiomas are very frequent, specially in middle-aged woman, if all or the vast majority of features favour this diagnosis, a relatively atypical bone affectation (lysis, periosteal reaction instead of the virtually pathognomonic hyperostosis) may not change the diagnostic orientation.

Bonus clues and some advance imaging pearls

Diffusion: Striking restriction in lymphomas
Perfusion: Striking high rCBV in meningiomas
Spectroscopy: Alanine (and GLX) in meningiomas. Striking high Cho in lymphoma and plasmacytoma. Striking high lipids in metastases

Back to the case:

ARE THE ADVANCED IMAGING TECHNIQUES HELPFUL?

FINAL DIAGNOSIS: MENINGIOMA (WHO GRADE 2)

TAKE HOME MESSAGE REGARDING MENINGIOMA

– Very frequent, specially middle-aged women
– Important to know the classic characteristic features, some of them are very specific; but recognize the great polymorphism/many faces of this entity
– Advanced imaging can be helpful
– Not all the lesions in a neoplastic patient are metastases

Neuroradiology #33

72-year-old male:
– With known pulmonary neuroendocrine tumor
– New onset dorsal pain

What do you see?

Vertebral blastic metastasis from pulmonary neuroendocrine origin presenting as an ivory vertebra.

IVORY VERTEBRAE (differential)

– Paget
– Lymphoma
– Metastasis on men: prostate
– Matastesis on women: breast

Do not forget: transitional cell carcinomas, neuroendocrine tumours, medullary thyroid carcinoma and osteosarcoma.

Neuroradiology #31

56-years-old female:
* Fever and seizures

What do you see?

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HERPES SIMPLEX ENCEPHALITIS

See the characteristic ABRUPT SPARING OF THE BASAL GANGLIA WITH THEIR “BORDERS THAT CAN BE DRAWN WITH A FINE-POINT PEN”.

Other tips:

* Temporal (with anterior and medial predominance) and insular> frontal (with basal predominance) and cingular
* Not rare bilateral
* Look for SAH foci near the silvian fissures

Neuroradiology #30

A 6-year-old boy presenting to emergency department with headache, nausea, and vomiting

What do you see?

Intra-axial cystic lesion with mass effect shows CSF signal intensity on all sequences, without enhancement and perilesional edema

Differential diagnosis include

* Parasitic diseases (hydatid cyst) spheric
* Neuroglial cyst may have surrounding gliosis
* Porencephalic cyst surrounding gliosis, communicates with ventricle

Same cystic lesion in superior lobe of left lung

What is the most likely diagnosis?

Hydatid cyst disease
Both lesions were treated by surgery

Neuroradiology #29

An 89-year-old female patient with aplastic anemia. 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 #28

A 24-year-old female patient with headache. What do you see?

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Multinodular and vacuolating neuronal tumor (MVNT): Cortical ribbon-juxtacortical T2 hyperintense (a-b) round to oval nodular lesions, not suppressed on FLAIR images (c) and usually no enhancement (d) may show fair enhancement rarely, without diffusion restriction (not shown)

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.

Toxoplasmosis

· 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

Click here to see more images

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 #25 – Flashcard

What do you see? What is the most likely diagnosis?

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Multiple sclerosis

Multiple white matter lesions involving the corpus callosum, peri-trigone region, subcortical, and deep white matter.
Ddx: other demyelination, vasculitis, small vessel disease, tosic/metabolic, watershed infarcts.