Hypodense meningioma. A care report

• Published in: Revista de neurologiá Vol. 26; no. 149; pp. 74 - 76
• Main Authors: García-Pravos, A, Gelabert, M, Arias, M D, González, J, Rumbo, R M
• Format: Journal Article
• Language: Spanish
• Published: Spain 01-01-1998
• Subjects: Aged; Brain Neoplasms - diagnosis; Brain Neoplasms - surgery; Diagnosis, Differential; Female; Humans; Magnetic Resonance Imaging; Meningioma - diagnosis; Meningioma - surgery; Tomography, X-Ray Computed
• ISSN: 0210-0010

Meningiomas are benign tumours which originate in the arachnoid layer and are characterized by being iso- or hyper-dense on computerized axial tomography (CAT). Hypodense meningiomas are relatively infrequent and normally behave thus because of their fat content. A hypomeningioma is almost entirely composed of adipose tissue. However, a meningiotheliomatous meningioma with fatty degeneration, which is the case being considered, is characterized by zones of meningiotheliomatous cells together with zones of adipocytes.
We present the case of a 73 year old woman with a meningiotheliomatous meningioma with extensive fatty degeneration which on CAT scan showed as a hypodense lesion, with well-defined edges, which took up contrast heterogeneously and produced a hyperosfosant reaction. On magnetic resonance (RMN) it gave signals of heterogeneous intensities. Up to the present time, only four cases of pure lipomeningiomas have been described in the literature.
However, meningiomas with fatty degeneration are much more frequent. In this paper we discuss aspects of the differential diagnosis of meningiomas which behave as hypodense lesions on CAT scans.