What are arachnoid cysts?

Also known as: intracranial cysts, intracranial arachnoid cysts, spinal arachnoid cysts

Arachnoid cysts are fluid filled sacs or cavities that appear on the arachnoid membrane and can present in many locations on the brain and/or spinal cord. Majority of these cysts are discovered incidentally and do not merit surgical intervention but rarely may cause headaches or progressive enlargement of the head.
 

What causes arachnoid cysts?

The exact causes of arachnoid cysts are unknown. Most experts believe that a majority of arachnoid cysts are congenital disorders or developmental malformations that occur due to the splitting or tearing of the arachnoid mater during gestation. There is reason to believe that heredity may play a role in their occurrence. Most of these cases manifest during infancy, but onset may be delayed until adolescence. Some arachnoid cysts might occur due to injury or disease after birth. Arachnoid cysts may be associated to other primary disorders such as Marfan syndrome, arachnoiditis, or agenesis of the corpus callosum (also known as ACC).
 

What are the symptoms of arachnoid cysts?

Small cysts may never cause symptoms and may be found incidentally. Specific symptoms depend on the size and  location of the cyst. A short list of the signs/ symptoms include: changes in the skull shape (cranial deformation ) , headache, nausea and vomiting, seizures,  bobbing and nodding of the head, ADHD, hydrocephalus, and many many others.
 

What are arachnoid cyst care options?

Arachnoid cysts that are asymptomatic and do not affect surrounding tissues usually do not require treatment (some believe that asymptomatic children should be treated to avoid future complications); children with symptoms will require surgery which may be one of a variety of procedures. Most treated children do well. Symptomatic and supportive may be provided.

Reviewed by: Jack Wolfsdorf, MD, FAAP

This page was last updated on: 1/29/2019 3:21:13 PM

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