Radiology Quiz 21031 | Radiopaedia.org

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Questions
Findings

What are the demographics of patients with intraventricular meningiomas?

Most intraventricular meningiomas present between the 4th and 6th decades with a recognised female predilection (M:F ratio of 1:2).

Question 2

Where are most intraventricular meningiomas located?

Show Answer

80% in the lateral ventricles (typically in the trigone); 15% third ventricle; 5% fourth ventricle.

The patient went on to have surgical excision of the mass.

Histology

MICROSCOPIC DESCRIPTION: The sections show a moderately cellular meningioma with attached dura. The tumour comprises whorls and fascicles with psammoma bodies. The tumour cells have ovoid nuclei with no significant nuclear pleomorphism. Up to 2 mitoses per 10 hpf are identified. There is a single small focus of necrosis. There is no evidence of tumour invasion into small amount of attached brain parenchyma.

The tumour cells show focal positivity for PgR. The Ki-67 index is approximately 1%.

DIAGNOSIS: Psammomatous meningioma (WHO Grade I).