What is Arachnoid Cyst?
Arachnoid cysts are cerebrospinal fluid covered by arachnoidal cells. They develop at the base of the skull, the surface of the brain, or on the arachnoid membrane. In rare cases, arachnoid cysts may also form on the spinal cord.
Arachnoid cysts usually are located in the skull, brain, and rarely, in the spinal cord.
The arachnoid cysts can grow to a large size if they continue to retain cerebrospinal fluid. In more extreme cases the cysts' size may cause the head to change shape or may displace the surrounding lobes of the brain.
Three different membranes make up the protective covering that envelops the central nervous system (the meninges). These layers, beginning with the most external, are the:
- Dura mater
- Arachnoid mater
- Pia mater
Cerebrospinal fluid is mainly contained between the arachnoid layer and pia mater. An arachnoid cyst forms when the layers of the arachnoid membrane split apart and become filled with cerebrospinal fluid.
Common symptoms of arachnoid cysts include:
- Headaches
- Nausea
- Vomiting
- Balance issues
Treating arachnoid cysts
The preferred surgical treatment at UPMC for arachnoid cysts is through small openings at the side of the skull. Doctors open (fenestrate) the cyst with the help of endoscopes in this minimally invasive procedure.
At UPMC, the preferred surgical treatment for certain arachnoid cysts of the skull base is the Endoscopic Endonasal Approach (EEA). This innovative, minimally invasive treatment technique uses the nose and nasal cavities as natural corridors to access hard-to-reach or previously inoperable tumors.
Benefits of EEA include:
- No incisions to heal
- No disfigurement
- Faster recovery time