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

Head and Neck #6

– 66-year-old female:
– Feels a lump in the neck when swallowing

In what space houses this lesion?

Mass in the right parapharyngeal space or deep part of parotid space. No parapharyngeal fat is visible, so either the lesion displaces the fat or it arises from it. It is certainly not from the carotid space, since the carotid arteries are displaced posteriorly. It is also not from the mucosal space since it compresses the lateral oropharyngeal wall, instead of arising from it.

Do you want further imaging to make a diagnosis and what?

MRI will provide you more details in head and neck lesions where the lesion arises from exactly, and what the origin is. MRI is made with T1, T2, and T1 with Gad and fat suppression.

What is your differential diagnosis?

Origin from deep parotid lobe, so DD benign or malignant salivary gland tumor, such as pleiomorphic adenoma, adenoid cystic of mucoepidermoid cell carcinoma. Radiologists are not good in differentiating benign from malignant lesions on MRI. Histopathology has to be done. DWI will help you a little, in that, malignant lesions have often lower ADC values, but also Wharthin tumors do so. DD rare schwannoma arises from V3 (mandibular nerve) in the true parapharyngeal space.

Solution

We performed ultrasound and cytologic punction. This turned out to be a fairly rare acinic cell carcinoma.

Teaching point: Malignant tumors of the salivary glands are well delineated and do not have to present as ill-defined lesions, nor have to have lymph node metastasis or perineural spread.

Emergency #34

A 73-year-old female:
– Pain LLQ
– CRP 68, leucocytes 19000.

What is the pathology?

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Diagnosis: Sigmoid diverticulitis, no signs of complications/perforation such as air bubbles outside bowel lumen or paracolic abscess. Reactive bowel wall thickening (always be aware of underlying carcinoma!)

Name the three coincidental findings:

1. Gall stones
2. Right adrenal mass, DD metastasis from 3. or adenoma
3. Right interpolar solid mass, suspect for renal cell carcinoma

Musculoskeletal #20

72-year-old alcoholic patient with intractable dorsal pain and legs numbness and weakness.

What do you see?

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IMAGING FINDINGS:

Thoracic spine compression fracture with posterior displacement of the posterior wall of the vertebral body compromising the spinal canal, cord compression and associated myelopathy. T2W image shows fluid and hypointense bubble-like artifact consistent with vacuum cleft in the collapsed anterior vertebral body

DIAGNOSIS:

Kümmel disease (osteonecrosis and collapse of the vertebral body)

TEACHING POINTS:

Intravertebral vacuum cleft and fluid within the collapsed vertebral body is a characteristic feature
Differential diagnosis includes a pathologic (tumoral) fracture, and the presence of air strongly favors osteonecrosis

Would you like to see a complementary case?

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MR T2-weighted and CT images to highlight the characteristic features of Kümmel disease

Intravertebral fluid seen on T2 image and air on CT image

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)

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