meningioma
Pronunciation: muh-nin-jee-OH-muh
Typically benign brain tumor arising from the meninges, the protective membranes covering the brain.
Full Definition
A meningioma is a type of brain tumor that develops from the meninges, the protective membrane layers that surround the brain and spinal cord. These tumors are typically slow-growing and benign (non-cancerous), accounting for approximately 30% of all primary brain tumors. Meningiomas can occur anywhere the meninges are present but are most commonly found along the brain's surface, particularly in areas such as the parasagittal region, sphenoid wing, and cerebellopontine angle. While most are benign, some meningiomas can be atypical or malignant, requiring more aggressive treatment. Surgical removal is often curative for accessible tumors, though some may require radiation therapy.
Usage
Usage note: Distinguish from other primary brain tumors like gliomas, which arise from brain tissue rather than membranes.
In Context
- "The large parasagittal meningioma was completely resected using a interhemispheric approach." — operative report
- "MRI characteristics suggested a typical meningioma with dural tail enhancement." — radiology report