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 debbie, its been awhile since i last checked in. you ask if anyone else out there has like symptoms. i do, the tightning sensations over the top of my head, theleft side of my head from back to around the left eye and sometimes like last night, from the left side to the right side of the back of my head, ear to ear. very strange sensation but not when your already not feeling too hot. i also have been dealing with being unable to turn my neck to far to the left when driving much less just because. to do so causes pressure and discomfort down the neck and up the back left side of my head. the last neurosurgeon i saw suggested i might want to have my neck checked too. the last several days i have had spells i call em of weakness, feeling like im in a fog, nausua etc. the latest mri shows no enlargment of the cyst, that its in the middle or midline. the dr told me its inoperable but couldn't be the cause. right now i am relieved to learn the ent says i don't have mastoiditis whch my primary put me on antibiotics for and to stop the antibiotics. he did oreder antoher cat scan cause he found a small somethin or other he wants to check out. meanwhile i feel like a pin ball cause my drs office is in the same building so i stopped and made an appt frist thing tomorrow morning to see her and share her collegues opinoion. also to get a refeerral to a good neurologist. i let you know what the drs say. good luck with your quest and God Bless lee
June 3, 2010 - 1:41pmThis Comment
Lee,
Thanks for sharing. I am at a loss for where to go and who to see. I'm doing physical therapy right now, but not much has changed. I don't feel like my neurologist is helping much. I had all of my mri's and a complete history I typed up reviewed by 2 orthopedic neurosurgeons at Columbia Presbyterian in NYC. They don't even see you. They just review your stuff and I was told that my neck stuff is inoperable which I pretty much thought would be the case. I have not yet gone back to the brain surgeon. I'm stumped at this point hoping things will just go away on their own. My neurologist and physical therapist seem to think that the eye sensations can be caused by neck stuff, but what do you do about that and how do you prove it's that and not the cyst especially for me since my cyst is moderately pushing on nerve 7 which is the facial nerves. I'm hoping somewhere along the way, I'll come in contact with someone who has an answer. Keep me posted,
Debbie
June 9, 2010 - 2:51pmThis Comment
Hi debbie,
I too understand the "pinball" sensation of being sent back and forth from one doctor to another, never getting good, solid answers. Reading about both your's and Lee's symptoms reminds me so much of myself. I too had strange eye problems and still do. So many doctors do not want to believe that these cysts can cause not only "all" these problems, but any of them. They have heard so long, that these cysts are normally asymptomatic that for them to switch gears and think that they could be the culprit of all our problems, is totally foreign to them. But they can. And it just depends on where the cyst is, and what it is pressing on as to what type of symptoms you have. If you know where your cyst is, do some research to find out what parts of the brain are in that area. Find out everything you can about your cyst....where it is, what in your brain is being compressed etc. That is what I did. I felt like I had to "sell myself" to doctors. It was rediculous. But it is what it took. I had to become "smart" at a time when I didn't want to have to think at all, just so I could prove to them that I knew what I was talking about and say "see.....my cyst is here, and this is what this part of the brain is responsible for."
Like Lee, I had that same fogginess....boy did I have that! It was horrible and got worse and worse over time. I contantly felt like I was living in a fog, or dreamworld...like the world around me was fake. Like it wasn't real. It was strange. What I did...my actions....seemed more out of habit rather than truly being in the moment.
Your symptoms, to me, sound like they could definitely be related to your cyst. As I have said many times, because I think it not only helps, but as your brain becomes less functionabe will help, keep record of your symptoms....day-to-day, hour-to-hour, whatever you need to, to mark the changes, differences, and day-to-day physical trials you live with. If you can, read up on the part of the brain that your cyst has grown on. Find out what its functions and responsibilities are. Once I did that, I knew I was right....my brain stem and cerebellum were completely compressed and everything I dealt with, had to do with the responsiblities of the brain stem and cerebellum...and then-some.
I wish you all the luck in finding someone who will listen to you and give you the treatment you deserve. Do not give up....there is someone out there who knows what these cysts are capable of. And they will "get it" and help you. It may take perserverance on your part to find them, but you will. But...if it were me, I would get on it, looking for him, because "IF" your cyst is and does what mine did....as time passed and my symptoms worsened, I couldn't put two thoughts together and that made my finding someone, a challenge. I couldn't think straight to save my life....my cyst was literally squishing my brain. If you can, enlist family to help you find a neurosurgeon. Send your recs, copies of your MRI, to a few different neurosurgeons, with a letter....a list of your symptoms.
I wish you all the best and please keep us updated....I will keep you in my thoughts and prayers.
Maria R.
June 10, 2010 - 4:18amThis Comment
they never have given me the size said that back in one of my last entrys. the nero surg said it is on the moderatly large size. think they dont want to say how big even though i can tell by the mri's that have been done. but the good new is that he is what they refer to as other wise nerologically intacked. But they have to drain due to the pressure on his cerebellum ( sorry if it is spelled wrong ) . thank you for being one of the many to add him to your prayers we will take all we can get fighting (so to speak ) for him.
May 26, 2010 - 6:06pmThis Comment
sorry i will also keep updating when i can.
May 26, 2010 - 6:09pmThis Comment
hi writting to update have not written since feb. my 13 yr old son was found to have a large posstior foosa arachnoid cyst. we finally found a great dr here some what local who has exp with these kinds of cyst. my son is going to have the cyst drain after 6/9 when school lets out here. thank you to all of u who help and just gave support. I will let all of u know how thing go after his surgery.
May 21, 2010 - 1:05pmThis Comment
Good luck with the surgery. I will keep him in my prayers. Please do keep us updated with the surgery and his progress.
Maria
May 23, 2010 - 6:53amThis Comment
Hi, first off, keeping your son and your family in my prayers. How large is his cyst?
May 21, 2010 - 3:59pmThis Comment
Hello all - just wanted to touch base - i have been following the comments in this forum - Believe me i feel for each and every one of you! Don't give up, keep up your will and Faith and seek the help that you need. If you are not happy with an answer - get another opinion. this is YOUR life. This is YOUR brain.......Take care of yourself. Look to your friends and family for strength and to help you get through this. do NOT try to get through it alone. Its way too much for one person to bear alone.......
May 21, 2010 - 8:19amOn an other note - i had my cyst removed on January 26th. My recovery was slow, but i am still i mproving every day. Fatigue is probably the worst thing i have to deal with. I have regained the strength in my lower extremities but one thing is really bothering me, which is why i guess i writing - I am suffering from short term memory loss. If i do not write it down, i lose it. Just an example - i came into work this morning and there was a file on my desk with a note: "the file you asked for". I have absolutely no recollection of asking for it, or why......
This is enough to cause a serious bout of depression - my job depends on me being able to carry out tasks which require my short term memory to be intact..........
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Thank you Pat I was thinking about this the same way. I was talking with my husband. I told him that maybe it is gonna help me with the headaches but it is not a solution for the whole problem. I have some other symptoms and this is not gonna fix it. So, my plan is to visit neurosurgeon next week I have found he is from Baylor Hospital in Dallas. I’m trying also get all my medical papers together, you know everything what was done. Make a copy and make images from CD and send it all to Phoenix. They have group of neurosurgeons Maria recommended one and Dia from that group recommended three others. I have to send them the letter and all my medical records. So I’m gonna do it. If I have to travel 18h I will do it.
April 8, 2010 - 8:10amI’m not gonna try this neurostimulator.
Grazyna
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