# Complex Factors in Hydrocephalus Development in Tuberous Sclerosis Complex: A Case Report of Subependymal Giant Cell Astrocytoma

## TL;DR

A 14-year-old with tuberous sclerosis developed a brain tumor and hydrocephalus, showing that multiple factors may contribute to fluid buildup in the brain.

## Contribution

Highlights the complexity of hydrocephalus development in TSC patients with SEGA beyond tumor obstruction.

## Key findings

- SEGA in TSC can cause hydrocephalus even after tumor shrinkage with mTOR inhibitors.
- Elevated CSF protein levels suggest impaired CSF outflow may contribute to hydrocephalus.
- Obstructive mechanisms alone may not fully explain hydrocephalus in these patients.

## Abstract

Subependymal giant cell astrocytoma (SEGA) associated with tuberous sclerosis complex (TSC) occurs in 5-20% of TSC patients, with a subset developing hydrocephalus. We present a case of a 14-year-old male diagnosed with TSC in the neonatal period who developed SEGA and subsequent hydrocephalus. Despite reducing the tumor size with the mammalian target of rapamycin (mTOR) inhibitors, ventricular enlargement persisted, indicating that obstructive hydrocephalus due to the foramen of Monro blockage was not the sole mechanism. Elevated cerebrospinal fluid (CSF) protein levels suggested additional factors like impaired CSF outflow. This case underscores the need for comprehensive treatment strategies and further research to better understand and manage hydrocephalus in TSC patients with SEGA.