Type:
Educational Exhibit
Keywords:
Neoplasia, Education and training, Education, Diagnostic procedure, MR, CT, Catheter arteriography, Neuroradiology brain
Authors:
V. Mayoral Campos1, M. J. Gimeno Peribáñez1, J. A. Guirola2, C. Bonnet Carron1, J. I. Pina Leita1, R. Lasierra Diaz1; 1Zaragoza/ES, 2ZARAGOZA, ZA/ES
DOI:
10.1594/ecr2013/C-1554
Background
Meningiomas are the most common primary brain tumors,
representing one-third of all such tumors.
They arise from the arachnoid "cap" cells of the arachnoid villi in the meninges.
These tumors are usually benign in nature; however,
a small percentage are malignant.
Imaging information about the dural attachment site,
location and severity of edema,
and displacement of critical neurovascular structures is useful for planning the operative approach and possible effects.
The World Health Organization (WHO) classifies meningiomas into 3 categories:
- Typical: these lesions are benign and account for 84% to 92% of lesions.
This includes the “variants” as meningothelial,
fibrous (fibroblastic),
transitional (mixed),
psammomatous,
angiomatous,
microcystic,
secretory,
clear cell,
chordoid,
lymphoplasmacyte-rich,
and metaplastic subtypes.
- Atypical: these demonstrate intermediate hypercellularity and mitotic activity.
They account for approximately 5-7% of lesions.
- Anaplastic or malignant: they are characterized by necrosis,
abundant mitoses,
and parenchymal invasion.
They account for 1% to 2% of meningiomas.
CLINICAL PRESENTATION
Meningiomas may be completely asymptomatic.
Symptomatology is dependant upon lesion location and size:
- Fozal seizures may be caused by meningiomas that overlie the cerebrum.
- Sylvian tumors may cause myriad motor,
sensory,
aphasic,
and seizure symptoms,
depending on the location.
- Increased intracraneal pressure can occur but is unusual.
- Diplopia or uneven pupil size can be symptoms if related pressure causes a 3rd and/or 6th nerve palsy.
Some people have sudden unexplained severe headaches (which may be accompanied by nausea and/or vomiting) or recurring headaches as the first signs of a meningioma.