subependymal giant cell astrocytoma
A benign brain tumor occurring almost exclusively in patients with tuberous sclerosis complex, typically located near the lateral ventricles.
Full Definition
Subependymal giant cell astrocytoma (SEGA) is a low-grade brain tumor that develops almost exclusively in patients with tuberous sclerosis complex (TSC). These tumors arise from subependymal nodules located near the foramen of Monro and lateral ventricles. SEGAs are composed of large, bizarre-appearing cells that show both glial and neuronal characteristics. While histologically benign, they can cause significant morbidity through obstruction of cerebrospinal fluid flow, leading to hydrocephalus and increased intracranial pressure. Symptoms may include headaches, visual changes, and cognitive decline. Treatment typically involves surgical resection, though the mTOR inhibitor everolimus has shown efficacy in reducing tumor size. Regular surveillance imaging is recommended for TSC patients to monitor for SEGA development.
Usage
Usage note: Commonly abbreviated as SEGA. Associated specifically with tuberous sclerosis complex.
In Context
- "Serial MRI revealed growth of a subependymal giant cell astrocytoma requiring surgical intervention." — Neurosurgical planning note
- "The patient with TSC developed hydrocephalus secondary to a large SEGA obstructing the foramen of Monro." — Neurosurgical consultation