What causes arachnoid cysts?

Arachnoid cysts develop when cerebrospinal fluid, the fluid that surrounds and nourishes the brain and spinal cord, fills sacs that develop in the arachnoid mater, one of the layers of tissue that surrounds the brain. Often, arachnoid cysts are present at birth. These are called primary arachnoid cysts and are related to developmental abnormalities. Secondary arachnoid cysts can develop because of infection or surgery of the brain or spinal cord and are uncommon.

What are the risk factors for arachnoid cysts?

A number of factors increase the risk of developing arachnoid cysts. Not all people with risk factors will get arachnoid cysts. Risk factors for arachnoid cysts include:

  • Brain infection such as meningitis (infection or inflammation of the sac around the brain and spinal cord)
  • Brain or spinal cord surgery
  • Brain or spinal cord tumor
  • Head injury
  • Male gender

What are arachnoid cysts?

Arachnoid cysts are fluid-filled sacs that develop between the central nervous system (brain and spinal cord) and the arachnoid membrane, one of three protective membranes that surround the central nervous system. Cells from the arachnoid layer produce cerebrospinal fluid, the fluid that protects and nourishes the brain and spinal cord. Consequently, arachnoid cysts are filled with cerebro... Read more about arachnoid cystsintroduction


What are the symptoms of arachnoid cysts?

Small arachnoid cysts are usually symptomless and may not require treatment. If arachnoid cysts grow significantly, they may cause symptoms, such as headache, weakness and fatigue. In serious cases, symptoms may become life threatening. Symptoms occur far more frequently in children compared to adults. Serious symptom... Read more about arachnoid cystssymptoms


How are arachnoid cysts treated?

If arachnoid cysts are small, they generally do not require treatment. But if they begin to press on the brain or spinal cord, treatment is necessary to alleviate symptoms.

Surgical treatment for arachnoid cysts

Surgery to treat arachnoid cysts is aimed at draining the fluid from the cyst or puncturing a hole in the arachnoid membrane, which forms the sac. Types of surg... Read more about arachnoid cyststreatments

Medical Reviewer: William C. Lloyd III, MD, FACS Last Annual Review Date: Aug 9, 2013 Copyright: © Copyright 2014 Health Grades, Inc. All rights reserved. May not be reproduced or reprinted without permission from Health Grades, Inc. Use of this information is governed by the HealthGrades User Agreement.

This Article is Filed Under: Brain and Nerves