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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Anon - We just heard from the founder of this group and you may find their website helpful. http://arachnoidcystawareness.com
March 4, 2010 - 6:55pmThis Comment
Hi Anon - Welcome to EmpowHER and thank you for writing. I'm sure it's been frustrating and probably somewhat frightening to get this diagnosis and then hear conflicting opinions. I hope that we will be able to help you.
If you have read through this thread you have seen that patients and parents of younger patients often get conflicting opinions and information. What is extremely important with conditions like this is to work with specialists who have extensive prior experience with the condition. Is there a hospital in your area that specializes in pediatric neurology? Are there pediatric neurosurgeons on your medical plan? If you don't have specialized facilities in your area do you have out of state and/or out of network options available through your health plan? The ideal situation would be to locate the best local specialists and reduce the need for travel. Can you let us know what you've been able to find out about the services available to you? If you need help in doing this let us know and we would be happy to assist you. We would need the name of the city you live in and the specific name of your insurance plan. EmpowHER does not recommend specific physicians and will not be able to give you specific names, but we can assist you with the research process so that you can make your own decision. We look forward to hearing back from you and learning more.
March 4, 2010 - 6:11pmTake good care,
Pat
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I live in Bartow Fl and have Blue cross Blue shield. I am near both all childrens in tampa and arnold palmer in orlando dont know if either one of these have specialists with extensive prior exp. there is also shriners in gainsville fl that is atleast in the state. if u could let me know if any of these have groups that will be able to get us headed in the right direction it would be very helpful thank u in advance for your help and experiences they have made it atleast less difficult to know that lot of people have the same trouble with this situation
March 4, 2010 - 6:48pmThis Comment
Hi all - Just wanted to give everyone an update. I went for a follow up to my "neurosurgeon" yesterday. (what amazes me is that i only saw him for the appointment with the initial diagnosis. After that - it was always the physicians assistant........) Anyhow - that doesn't bother me - i did extensive research on the neurosurgeon and i know that i was in good hands. I had been experiencing some "aching" and pain in the back of my head - just at the base of the occipital bone (where the tumor/cyst was) Very, very sensitive to the touch - the only way i could explain what i was feeling was when i rested my head on a pillow, if i leaned my head back while i was sitting in my chair, etc. was that "the piece of skull they removed was pushing into my brain and giving me a headache". I was told that this is very normal for the type of surgery that i had. Also-the band from my headgear on my cpap goes right across that area so that will also increase the discomfort in that area (anyone have any ideas on how to resolve this issue?). They switched my muscle relaxer so that i can take one and still go to work (non-drowsy), and told me that my fatigue - i could expect to continue feeling it for several more months.....wonderful.......
March 3, 2010 - 6:43amThe good thing is that everything i am feeling is perfectly normal, there are no symptoms that are causing any concern (other than the meds wreaking havoc on my system), and as slow as it may seem to me, I am recovering as i should be.
I still get depressed when i am tired - i get to a point where i feel like a ran a marathon and all i did was walk through a couple rooms.......I have always been a go, go, go, person so this really bothers me - the good thing is that i know "eventually" all this will go away and i will be myself again.....
Thank you all for your support - i really don't know what i would have done without you........
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Hello everyone!
I recently was diagnosed with a posterior fossa arachnoid cyst. Initially began seeing an ENT for being off-balance, dizzy, vertigo symptoms and pressure in my head (specifically in the back of my head). Especially when I walked and drove and/or my head moved. After a string of medication did not help, he sent me for a CT scan and MRI, which is when the cyst was found. I was referred to a neurosurgeon, whom I saw today, and was told these symptoms are not due to my cyst. Everything I have read about my symptoms, pressure in the back of my head, vertigo symptoms seem to point to what an AC can cause. He stated the pressure in my head could be due to headaches, tension headaches, that sort of thing but did not believe he could do anything to help me because he felt surgery would not relieve my symptoms. The strange thing is I have not been experiencing any sort of headache, just pressure.
After reading everyone's posts, it makes me question whether or not I should seek a 2nd opinion.
Thank you to everyone who has posted their stories. In a way, it gives me hope that one day I too can deal with this. 3 months of not being able to travel or drive long distances has truly discouraged me, and today being told my symptoms are not due to the AC has truly dampened my spirits.
Adrian
March 2, 2010 - 4:53pmThis Comment
Hi Adrian, and welcome to EmpowHER. Thanks for sharing your situation with us, and I'm glad we've been able to help. My personal opinion and practice is to always seek a second opinion when major surgery is involved. I also learn as much as possible about any physician that is treating me. Are you able to find out the background of the neurosurgeon you were referred to and his experience with posterior fossa arachnoid cysts? Also, I'm not clear on what you're saying the neurosurgeon said - is he saying you don't need surgery? that surgery won't help you? that there is nothing he personally can do to help you?
Three months of dealing with a problem and wondering what has caused it and then not getting answers has got to be discouraging, but please don't let it get you down. We will help you find answers and are here to support you.
Take care, Pat
March 2, 2010 - 5:24pmThis Comment
Hi Pat. You are correct, I too believe a 2nd opinion would help settle my nerves. I was able to find out a little about the neurosurgeon prior to seeing him. He's been in practice for 25yrs, and does have experience with posterior fossa AC's. He stated, surgery would not help alleviate my symptoms since he did not feel they were being caused by the cyst. Very discouraging, especially since the pressure I feel in my head is exactly in the area the cyst is located. He advised me that I should seek further treatment with my family doctor or I could continue testing with my ENT for my vertigo issues. He did order an additional MRI in 6-9 months if my symptoms become worse, and to also see if the cyst has grown.
I contacted my ENT to advise him what was decided. We are going to pursue Balance Testing next week.
I'm hoping to find out more from a 2nd opinion from a neurosurgeon since the 1st doctor's explanation did not leave me with a good sense that my symptoms are not from the cyst. I truly believe after reading extensively about this condition that my dizzy spells, being lightheaded, off balance and pressure in the back of my head is due to this.
I truly appreciate the support from EmpowHER. And as strange as it sounds, it was a relief to find this site and to know I am not the only person experiencing this condition.
Take care,
March 2, 2010 - 7:00pmAdrian
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Hi Adrian,
I just want to tell you first that I am sorry you are having these problems. There is nothing worse, in my opinion, to not feel well and try to get to the bottom of it. Sometimes you feel so alone in yur endeavors. But I have to say that I agree with you pursuing the cyst as being the cause of your problems. These cysts are known for putting pressure and adding pressure to your head. I could not get anyone to believe me about the pressure I dealt with, and that it was coming from my cyst. It took nearly a year before I found someone, Dr. Robert Spetzler, to believe me, and understand what I was talking about. Many times, doctors who do not fully understand these cysts, only go by their medical books. When they read that they do not "normally" cause problems, they tend to not think out-of-the-box.
Keep looking. See as many doctors as you need to, and I would stick with neurosurgeons if it were me in your position. These other branches of medicine are even less familiar with brain cysts, and they will just run up a bunch of bills for you ordering a slew of tests that will not only, "not" tell them anything, but keep you running to other specialists. If it were me in your shoes, and felt as sure as you do that it is your cyst, I would get more opinions in the neurosurgery field. If you see several of them and they all agree it is not your cyst, then maybe pursue other options. Personally, what you describe as your symptoms, sound so much like what I dealt with that it is hard to believe that it "isn't" your cyst.
Of course, this is up to you. This is just my opinion and knowing the information I know, and what I dealt with. Keep us updated with your endeavors. I wish you all the luck and will keep you in my thoughts and prayers.
Maria
March 3, 2010 - 6:30amThis Comment
Hello Maria,
Thank you so much for the words of encouragement. It truly gives me hope that this can be corrected. I began calling neurosurgeons yesterday, 2 did not take my insurance and I have a listing of in-network doctors to begin calling today. I have canceled my balance testing with the ENT since my gut tells me this has nothing to do with my ears.
You're correct, it's very frustrating to have someone tell me my symptoms have nothing to do with the cyst. How can it not? Pressure, directly over it's location, imbalance, dizziness when my head moves. There have been times the area where it is located throbbed so much with pressure, that the roots of my hair hurt and I couldn't touch it, if that makes sense?
Did Dr. Spetzler decide to do surgery to drain the cyst? If so, how are you feeling?
I will definitely keep the group updated. And again, thank you for the kind words and support.
Adrian
March 4, 2010 - 3:42amThis Comment
Hi Adrian,
Sounds like you're making steps in the right direction. It would be hard to believe that it could be anything else, in my book anyways. Your symptoms literally mask mine. I had the exact feelings you describe, the dizziness (didn't know where it was coming from and was told it was all kinds of other reasons other than the cyst), my head ached at the back where the cyst is to the point where I couldn't lean it on the back of a recliner, or the seat in the car without it just killing me. My balance started getting bad, all kinds or strange things.
My surgery that Dr. Spetzler performed was to fenestrate it....this means that he took a wand and went into the cyst directly and knocked down all the walls that had built up within the cyst. He then got the cyst "communicating" with the rest of the cerebral spinal fluid, which means that he got the fluid to be able to move in and out of the cyst freely without getting hung up inside, which was what was making the cyst grow bigger in the first place. However, his endeavors didn't work. Just a few months after the fenestration, all my symptoms returned and it was decided I needed a shunt. Although the surgery itself worked, my cyst had pushed everything on the back of my brain downward and was blocking the normal channel of CSF flow...where the CSF flows down the back of the brain and down the back of the neck. He described it as someone stuffing a ball in a drain and the water cannot get around it so it gets backed up. So the shunt prevents CSF from building in the cyst or otherwise.
Dr. Spetzler told me in the beginning that he could not remove the cyst due to it being so large, and that because seemingly, I've had it all my life, my brain expects it will be there. So to remove it would put my brain into shock and I would certainly die. So that was not an option for me, although that is what I thought and wanted to have happen in the beginning before I knew all the logistics.
Well Adrian, stick to your guns. Personally I think you are on the right track. These cysts can cause all what you are describing and I would not give up until I found someone who believed me and agreed that intervention with the cyst is what you need. You know your body better than anyone, and feeling pressure in your head is not normal....and that is what these cysts do - build up pressure and you feel it. You feel like your head is under water, like you can't think clearly. The world, at times, may even seem kind of cartoonish because you aren't seeing clearly anymore. Once my first surgery was over, I remember waking up in my room and looking at the TV on, and thinking..."gosh I can see!" Everything seemed so clear and vibrant, and not distorted or garbbled.
Let me know how it goes as you try to get things in order. If I can be of any help, please let me know. Good luck with your endeavors to find the right neurosurgeon! I'll pray that you do soon so you can start getting the treatment you need!
Take care-
March 4, 2010 - 5:58amMaria
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