Emergency #15 – Flashcard

62-year-old female.

* Sudden collapse
* Headache
* Paresis of mouth left-sided
* Pupil difference L>R

What is the most likely diagnosis? What should be the next diagnostic step?

Diagnosis: PCOM aneurysm subarachnoid bleed (with subdural hematoma, intraventricular bleed, midline shift, hydrocephalus)
Next step:CTA (you already see aneurysm on NECT)

Neuroradiology #15 – Long case

42-year-old male:
* Presenting with dizziness, vertigo and loss of coordination

What is it?

A focal expansile single lesion.

How is it like?

* Nodular
* Solid
* Hyperdense
* With moderate perilesional edema and mass effect deforming the 4th ventricle without signs of active hydrocephalus (not shown)
* With avid enhancement

Where is it?

Left posterior fossa.

Is the lesion intraaxial (cerebral hemisphere) or extraaxial (cerebellopontine angle)?


Suggestive of extraaxial location:
1) Peripheral location and wide dural contact
2) Changes in the adjacent skull vault bone
3) Dural Tail

Definitive for extraaxial location:
1) CSF cleft.
2) Interposed vessels, cortex or dura.

The lesion is intraaxial, located in the left cerebellar hemisphere.

Which are the differentials for intra- and extraaxial posterior fossa tumours?


* HEMANGIOBLASTOMA: Most frequent posterior fossa primary tumour in adults. Strong association with von Hippel Lindau disease. Cystic tumour with mural peripheral solid avidly enhancing nodule. Perilesional pathologic vessels.

* METASTASES: Most frequent posterior fossa tumour in adults. Expanisve focal lesion, single or multiple, well defined, solid-necrotic, great edema, and mass effect.

* GLIOMA: Pilocytic astrocitomas (cystic tumour with solid mural nodule) and diffuse brainstem gliomas (often low-grade, infiltrative, ill-defined lesions without enhancement) much more common in peadiatric population. High-grade gliomas (infiltrative ill-defined lesions with heterogeneous enhancement and necrosis) are uncommon in the posterior fossa.

* MEDULLOBLASTOMA: Paediatric population (more common): Intraventricular, midline; young adults; parenchymal, paramedial, focal solid enhancing lesion. Different subtypes that share hypercellularity as main feature: CT hyperdense, T2 Hypointense and difussion restriction. High propensity for CSF dissemination.

* LYMPHOMA: Focal solid enhancing single lesion or multiple cloud-like enhancing lesions. Hypercellularity as main feature: CT hyperdense, T2 hypointense and diffusion restriction.

* SUBEPENDYMOMA: Adults, intraventricular 4th ventricle. Plastic. None or little enhancement.

* EPENDYMOMA:Paediatric population: intraventricular posterior fossa; young adults: supratentorial periventricular. Plastic, heterogeneous, solid-necrotic, enhancing tumour.


* MENINGIOMA: Calcifications and bone hyperostosis

* SCHWANNOMA: Intralesional cyst and bone remodelling

* EPIDERMOID: No enhancement, restricted diffusion



* Mineralization
* Hemorrhage
* Hypercellularity
* Melanin

The images, now supported by diffusion and ADC map, highly suggest and hypercellular tumour

There are two most reasonable diagnostics.

Which are the two most reasonable diagnostics?

MEDULLOBLASTOMA AND LYMPHOMA : Could be appropiate diagnositc options for a lesion with this semiology.
The final histologic diagnosis was: Primary CNS lymphoma


* Abscess
* Lymphoma
* Acute infarct
* Epidermoid

Special tip

In the DSC Perfusion sequence:

* Low relative cerebral blood volume (rCBV) assessed in the colour maps
* T1 Leakage effect assessed in the curve could have helped in the preoperative diagnostic of lymphoma against medulloblastoma.

Abdominal #4 – Long case

27-year-old female:
* No previous history
* Presents with acute kidney insufficiency
* DD glomerulonephritis
* Nephrotic syndrome
* US to exclide post-renal obstruction

US: Bilateral hydronephrosis and hydro-ureter. No obstructing mass or stone visible. Bilateral loss of parenchyma, indicating chronic problem.Mobile bladder stone.

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Patient receives bilateral nephrostomy. On antegrade pyelography no calibre changes or strictures, not proximal or distal. No cause for hydrnephrosis and hydro-ureter bilateral.

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Non-enhanced abdominal CT to evaluate nephrolithiasis. Traction on sigmoid, coecum and small bowel, andalso traction on bladder roof. Consider endometriosis in the differential diagnosis and perform MRI pelvis.

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MRI pelvis. Medialised adnexes. T2 hypo-intense fibrotic plaque centered on uterus very suggestive for deep invasive endometriosis (DIE). Fibrotic changes between uterus and rectum, uterus and bladder and uterus and bowels. No endometrioma cysts. Central in fibrotic area small aircollection with fistula towards anterior fornix (not completely shown here), with small abscess on major labia.

What is the most likely diagnosis?

Diagnosis: Endometriosis

Musculoskeletal #4 – Long case

Regarding the following X-Ray:

Frontal x-ray of the right hand

Where is the lesion?

Metaphysis of the base of the fourth middle phalanx.

What are the radiological characteristics/findings?

Expansile lytic lesion (bubbly appearance) with narrow zone of transition, no cortical break through, and no soft-tissue component.

What is the differential diagnosis?

Enchondroma: Enchondromas have variable imaging appearances but are typically lytic lesions with non-aggressive features. They could show chondroid calcifications (rings and arcs calcification). But in the hands and feet they are typically purely lytic with no matrix.
Eosinophilic granuloma: It mainly involves the diaphysis and does not cross the growth plates. It appears as punched out lytic lesions without sclerotic rim.  Imaging appearance in the long bones depends on the phase of the disease which is imaged. It can look aggressive in the initial phase. In the healing phase it can show solid benign periosteal reaction.
Fibrous dysplasia.Usually shows ground-glass matrix but may be completely lucent or sclerotic. Well-circumscribed lesions with no periosteal reaction may lead to premature fusion of growth plates leading to short stature in the lower limbs and bowing deformities (Shepherd’s Crook deformity of the femoral neck)

What is the most likely diagnosis?

Diagnosis: Enchondroma

Regarding the diagnosis…

What are the associated syndromes with multiple enchondromas?

Ollier disease: multiple enchondromas are usually  confined to one side of the body and limited to the limbs. There is increased risk of chondrosarcoma 

Maffucci syndrome: multiple enchondromas with soft-tissue haemangiomas

Emergency #14 – Flashcard

18-years-old male:
* Rigid abdomen and generalised tenderness
* Pain lower abdomen
* CRP 250

What do you see? Perforated appendicitis? What is your diagnosis?

Diagnosis Perforated sigmoid diverticulitis (Hinchey 3 or 4, peritonitis)

> Mesenterial fatty infiltration, free air bubbled outside bowel lumen.
> Also subdiaphragmal free air and free fluid.
> Notice enlarged reactive lymph nodes and peritoneal thickening and enhancement, indicative of peritonitis.
> Patient was operated, free faeces was found in the abdomen.

Hinchey classification of acute diverticulitis:
* Stage 1a: phlegmon
* Stage 1b: diverticulitis with pericolic or mesenteric abscess
* Stage 2: diverticulitis with walled off pelvic abscess
* Stage 3: diverticulitis with generalised purulent peritonitis
* Stage 4: diverticulitis with generalised faecal peritonitis

Cáceres’ Corner Case 210 – SOLVED

Dear Friends,

showing another case seen during this summer. Preoperative chest radiography for knee surgery in a 57-year-old man. More images will be shown on Wednesday.

What do you see?

New images are shown:

Click here to see more images

Click here to see the answer

Findings: PA radiographs shows a right mediastinal mass at the level of the tracheal bifurcation (A, arrow), which has not changed significantly in comparison with a chest film taken for pneumonia one year earlier (B, arrow).

Several of you have mentioned a triangular shadow at the right cardiophrenic angle
(A-B, red arrows). This appearance should suggest paracardial fat pad as the first choice.

The differential diagnosis of a right mediastinal mass at the level of the tracheal bifurcation is simple: most of the times it is either an enlarged azygos vein or lymphadenopathy.
 CT shows a dilated azygos vein with a prominent azygos arch (C-D, arrows), suggesting a impeded blood flood either in the inferior or superior vena cava. Considering that the patient is asymptomatic, the most likely diagnosis is congenital interruption of the inferior vena cava, with azygos continuation. The diagnosis is confirmed noting the absence of the suprarenal portion of the IVC (C, circle) and the association of other congenital anomalies, such as polisplenia (C, red arrows) and abnormal bifurcation of the bronchial tree (E, arrows).

Coronal CT confirms that the triangular paracardial shadow represents paracardiac fat.

Final diagnosis: Congenital absence of IVC with azygos continuation
Congratulations to MK, who made a late (and accurate) diagnosis of prominent azygos vein
Teaching point: remember that the most common right lower paratracheal masses are either an enlarged azygos vein or mediastinal lymph nodes.