An arachnoid cyst is a fluid filled sac that develops primarily in the uterus during the development of the brain and skull. The arachnoid membrane of the brain splits, and the split space fills with fluid known as cerebral spinal fluid. The fluid will enter the split area, but it cannot escape at the same rate as it enters. Because of this, the cyst will grow over time. The growth rate depends on many factors, but even as it grows, more times than not, the cyst will remain asymptomatic. This means that generally, an arachnoid cyst will not cause any symptoms.
Arachnoid cysts can grow anywhere on the brain with the primary areas being the side of the brain, and the top of the brain. When a cyst forms on the back of the brain, this is called a posterior fossa arachnoid cyst. A posterior fossa arachnoid cyst can create pressure on the brain stem and the cerebellum. These are extremely vital organs of the brain and they both produce tremendous functions that are required to live.
The brain stem controls a lot of our everyday functions that we do not even think about. One thing it controls is our body temperature. It controls our diaphragm for breathing, and it is where our hunger and thirst are controlled. It is also the path in which all our nerves leave the brain and travel throughout the body. The brain stem controls our pain, it is also where the nausea center is based, and it plays a role in the regulation of our hearts.
The cerebellum; on the other hand, helps control our balance. It plays a role in the reflex of our muscles, and plays a major role in our motor skills. Both parts of the brain have their very specific tasks, and when either one is compromised, it can reek havoc on the entire body.
If treatment is needed for an arachnoid cyst, usually the first choice is a fenestration of the cyst. This means going into the brain with a wand and opening up any walls that may have formed inside the cyst. These walls trap the fluid inside the cyst. The idea of this procedure is to get all the cerebral spinal fluid flowing in and out of the cyst efficiently so that the cyst does not continue to grow. If this procedure does not work, a neurosurgeon may decide to put a shunt in. A shunt helps to keep the cyst draining and not allow fluid to build up inside. If the cyst is small enough and in a space on the brain that is not too dangerous to remove, the neurosurgeon may be able to remove it altogether.
Symptoms can show themselves in many ways; from balance problems, nausea, vomiting, headaches, even seizures. Many cysts are discovered on accident when having a scan for another reason. They can be seen on Cat Scan, but the preferred diagnostic test for a brain cyst, is an MRI.
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Hi SWEL- Thanks for sharing your comments with us and welcome to EmpowHER. You've no doubt noticed that we're a women's health site, but I want to assure you that men are welcome, and we have a couple of guys who are also dealing with arachnoid cysts. I'm sure that they, and all of the female members, welcome you too.
October 8, 2010 - 4:33pmWe have several threads on this topic and we also have a support group at https://www.empowher.com/groups/arachnoid-cyst-support-group
I've sent you an invitation to join the group, and look forward to hearing more from you in the weeks ahead.
Thanks for being part of the community,
Pat
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DHR_110 - All surgery carries risks, including brain surgery. The following article provides an overview of brain surgery and the risks that it carries. http://www.nlm.nih.gov/medlineplus/ency/article/003018.htm
Your doctor is in the best position to advise you on whether there are medications available to reduce the cyst or if surgery is necessary.
The following article on brain cysts from the American Brain Tumor Association provides a lot of general, basic information which may address some of your questions and concerns. http://www.abta.org/sitefiles/sitePages/4F77F57A14D6EBBE5C3FBC447B78FD57.pdf
Only your own doctor, who has your medical history and specific diagnostic information, can provide the specifics that you're seeking.
Good luck to you, we wish you the best.
September 14, 2010 - 6:16pmPat
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hello,thanks for your words of support,my problem is that i dont have any symptoms of arachnoid cyst but still it is of a mid sized cyst.i was having fits for the last 3 years but only one fit in a year that was why i went to a doctor,he suggested me to have an mri,im very confused please tell me how much time does burr hole surgery takes and how risky it is.please reply.
September 14, 2010 - 2:18pmThis Comment
Pat is absolutely right that these are things you must discuss with your surgeon. I can tell you a burr hole is merely the way to open your skull, and is not the brain surgery itself. A burr hole only takes a few minutes, but the surgery once the hole is there will vary depending on what you need done. It's like opening a door so they can reach your brain inside.
Please write down all of your questions and take them to your surgeon, and if you are concerned about whether your surgeon's recommendations are right for you, seek a second opinion.
Good luck.
September 15, 2010 - 7:01amThis Comment
Hello,Im recently diagosed with arachnoid cyst in posterior fossa in right retrocerebellar region.im very scared please tell me what to do.Tell me is brain surgery risky? what are the chances? and is there any medicine to cure this without having any surgery.thanks please reply.
September 10, 2010 - 2:28pmThis Comment
Hi Anonymous
I'm sorry about your diagnosis. I know it is very scary.
We cannot address specific risks or treatment for you, because every case is a little different. Your surgeon is the best person to discuss risks and treatments with you. Once you get information from your treating neurosurgeon, then you can research with more detail.
Brain surgery does carry risks, as does any surgery. When it comes to the brain location and size of the problem are crucial to how you can be treated. There is not room in your skull for anything that takes up a lot of space, which is why brain tumors and cysts can be such a problem. The exact location is hugely important. Some parts of the brain can be more safely manipulated than others. Sometimes a small growth that does not get larger can just be left alone.
Discuss the details with your neurosurgeon. Get the information in writing, then begin your research. We will be happy to help you if we can. Be sure to get a second opinion. If it is possible, it is good to go to a teaching hospital with a large neurosurgical department, as they tend to have/be aware of the most recent information and treatment modalities.
I don't know if you are aware that we now have a support group here on the site addressing these issues: https://www.empowher.com/groups/arachnoid-cyst-support-group.
Thank you for writing. Please let us know if we can help you further.
September 10, 2010 - 5:38pmThis Comment
I am the orginal poster regarding 12 y/o daughter with all the diagnoses and just found out she was born with this cyst.
My daughter goes to the neurologist tomorrow for an EEG and to see the doctor after the EEG. I'm going to request MRI and hope I don't have problems. My pediatrician refused to refer her for an MRI. I have family in the east coast and the west coast in California. I am going to search doctors in those areas for a neuro-surgeon. I heard of a good one at Chops in PA. That way I will not have hotel expensese and I will know she's in good hands.
My struggle is getting an MRI to send to a doctor.
The cyst has been discusssed to my daughter and in front of her. Now when my daughter doesn't do what I told her to do she starts crying and says, "I don't know what's wrong with me I just can't remember things or I didn't understand etc." She does have a history of not doing what I tell her to do and she has told me in the past she forgot or didn't understand or something to those effects.
Now it seems like she's repeating things I have talked about. I don't know if it's real or if she's using that as an excuse now? She also asks me why she's not "normal" and why she can't just be like the other kids. I told her that she is normal and then she said that if she's so normal then why has she gone to so many doctors and so many places her whole life and her sister hasn't.
I don't know what to say to her. If I try to explain it like one would be able to do with a "typical" 12 y/o she wouldn't understand and she'd get frustrated. I try to use simple terms but she still doesn't always understand.
She tests average on an IQ test....a 96. I know she's smart. It's just language processing problems. Launguage processing problems was confirmed by developmental pediatrician and speech pathologist. They believe this cyst could have a lot to do with her problems although it's not their speciality. They helped me get into this neurologist we are going to tomorrow. I called neurologist last week and we already have EEG and dr. visit tomorrow.
In fact dev. pediatrician and speech dr. are not writing their final reports until hearing back from neurologist. They don't want to diagnose her with anymore developmental delays, learning disorderss, or anything else until the neurological aspects are explored.
August 31, 2010 - 7:50amThis Comment
My 13 yr old son always told me that he just forgot and then his cyst was discovered. I think atleast in my sons case his cyst did cause those kinds of issue. Since his surgery on june 16 it is almost like having a different child. He is still his self just all the issues are so much different now. He is still a teenager but the extreme mood changes and the memory issue are more like that of a normal teen. I talked openly to my son when we found out about his cyst and had the same worries that you are talking about. I think looking back and talking with him about these thing now it was more like he finally felt like there was a reasons for him having all the issues he had. From parent to parent I dont think that it is a bad thing that your daughter is inform with what is going on in her body. It was very hard for my son before we found out what was really going on in his body and he could not explain to anyone. Before his surgery he was on meds for ADHD, seeing a theropist and in all kinds of help groups for kid with behavior issues. Now he is on no meds and he has had no problems other than the normal teenage stuff so much different from what I was use too. I tell everyone that I have had to start relearning my son. The things I had gotten use to doing and sign the lead to blowups no long signal the same things. Keep the lines of communication open with your daughter remember she is just as scared and in the dark as you are.
August 31, 2010 - 7:00pmThis Comment
Anon - Since you last wrote to us we have added a Groups feature to our site and now have an arachnoid cyst support group. I want to encourage you to register for our site and join the support group to get the benefit of help from others with cysts and other caregivers. You don't have to use your real name if that makes you uncomfortable. Sometimes the caregivers get left out in the healthcare system, and they often have considerable responsibilities and stresses to deal with. We have many warm, caring people who are members and only wish the best for you and your daughter. Please keep us posted, and take good care. Pat
August 31, 2010 - 5:20pmThis Comment
Thanks for the advice Maria...Actually thouh I have had that particular condition off and on for 15 yrs.. When I have a "seizure", my body goes numb and just shuts down. To anyone waching me, I appear to be unconscous, but actually I can hear evrything being said around me, but I cant make my body react to my commands. When I come out of ,the "seizure" I feel as if I have just run a marathon, my body is spent and I just drift off to sleep for a few hours. I guess like me , you have had a hard time making others understand about your body numbness. I know that I cant explain it to the doctors in a way that they understand; or anyone else for that matter.....anyway thank you once again, and take care...Ray
August 29, 2010 - 10:41pmThis Comment