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
March 29, 2016 - 5:50amI have had my diagnosis for 7 years too
Right posterior fosser cyst - right medulla angle - near the brain stem - spine .
Trust me the symptoms you have are on par with mine - the flatness in personality - no motivation _ muscle twitches- joint pains and noises in the neck - spine - tingles - numbness- on and on it goes - we are strong to put up with this ! I am looking for surgery - what are you going to do ?
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Dr. Jeremy Schmahmann describes your symptoms in his work on the cerebellum--you might want to check him out.
July 20, 2016 - 5:22pmThis Comment
Well I've been seeing a neurologist and since I passed the basic neuro exam and had a normal EEG he hasn't said anything about removal of it. I want to have it removed because I've read so many stories of people with the same thing and same symptoms where the doctors all say the cyst isn't causing the symptoms. But if there's that many people with the same symptoms and same cyst I'm thinking the doctors don't really have a clue as to what they can cause and when they are causing symptoms or aren't. Any mass in your brain I'd think is going to cause some sort of symptoms I believe because of how involved the brain itself is. Don't think I can see a neurosurgeon without a referral from the neurologist.
March 29, 2016 - 12:25pmThis Comment
I have a question. My fiancé has an arachnoid cyst and he needs to know the dangers of air travel with this cyst. Can it be life threatening? He also suffers from epilepsy.
December 4, 2015 - 6:29pmThis Comment
I just have a question for anyone who can help. I too have an arachnoid cyst on my brain, I also have Empty Sella Syndrome and I suffer from Pesutotumor Cerbri. On top of all of that I had a herniated disc in my neck and had to have my disc fused and a metal plate and 4 screws put in. I am only 33 yrs old, but over the past 3 1/2 years my life has changes drastically. I am no longer able to work, I couldn't drive for 3 years, I still have a lot of neck pain from arthritis that has set up in my neck and I have headaches and am nauseated every single day. I honestly can not function a lot of the time. My question is... Has anyone applied for social security due to having the cyst and all of the debilitating symptoms? If so has anyone been approved? I have applied and been denied and then I appealed it, but was denied again. I appealed it again and was denied again. I am currently in the process of refiling. I haven't worked since 2012 due to my health. I also had 2 other female surgeries in the past year and a half. I know I have all of the credits or whatever they're called because I started working full time when I turned 16. I was just wondering if anyone else is having problems getting approved or if I'm just getting denied because I'm so young. Thank you.
December 1, 2015 - 12:27amThis Comment
I have had symptoms for more than 2 years and until recently i became basically debilitated. As someone stated earlier, I feel spacey (not all there), extremely fatigued, issues with balance, vertigo, and most recently, very sensitive to screens like phones and computers. Symptoms also get worst with little sleep, caffeine, and other things. They found the cyst which is over 9 cm in length and told me it is not big enough to be blocking enough flow. I find this odd because i am 27, healthy, and now am debilitated due to these symptoms. I don't know what i need to do to convince these people that it is due to the cyst. I mean what else could it be? I am honestly exhausted because the medical system is truly frustrating. How can a healthy young woman be debilitated for so long and they do not think it is related to the arachnoid cyst???
November 13, 2015 - 10:18amThis Comment
I have been having the same symptoms since March 2012. I have been diagnosed with a couple of different things. I have a Empty Sella Syndrome, Pesutotumor Cerbri and I also have an 8 mm arachnoid cyst posterior fossa. I have been to TONS of doctors all over Louisiana. Top surgeons at LSU Medical Center have been treating me for over 3 years now. I had to stop working and driving and I also had to walk with a cane for awhile. I was DIZZY constantly, Headaches, numbness everywhere and a long list of other symptoms. I am only 33 and can't function. Currently I have had a severe headache since November 1, 2015 every single day. If I'm awake I have a headache. It's horrible!!! My friend who use to be an RN told me about a hospital in Houston, Tx. I found a Dr over there. He's looking over all of my medical records and I'm sending 6 disks with MRI's and CT scans to him tomorrow. His name is Dr. Dong Kim. He is supposed to be one of the top neurologists in the United States. He even does free consultations over the phone. He just did surgery on a man from Michigan in October. The man had a brain tumor, it was cancer and his neurologist in Michigan performed 1 surgery and removed half of it. But, he said it was too risky so they found Dr. Kim in Houston the man flew in and the Dr performed the surgery now he's cancer free. Google him, maybe he can help. Houston, Tx Dr. Dong Kim. Good luck and you are not alone!!!! Hang in there and God bless you!
November 30, 2015 - 11:55pmThis Comment
I discovered last month i have a "posterior cranial fossa arachnoid cyst" after my neurologist refer me to have a CT scan of my brain for the headaches and dizziness i was experiencing. There is also hypoplasia of a basilar artery mentioned on the CT SCAN report.
November 13, 2015 - 3:25amI have had headaches for as long as i can remember and have gotten worse the last few years that can last for days or a week and causing severe vomiting and faint feeling. I event passed out once.
I cannot take an MRI as i have a rod in my spine implanted at the age of 13 for Kyphoscoliosis.
I am from Cyprus and i am not sure there is a doctor here with enough knowledge on arachnoid cysts :(( i don't know what to do or who to see for a second opinion. I have only learned about these my self now and reading your article and all these comments, has got me worried now but the doctor just said we should have a ct scan again in a few months or a year to see if it has grown. Nothing else. she prescribed magnesium and some vitamins for the dizziness. Sorry for making this long but i feel so lonely in this because i have been experiencing other symptoms for years - feeling really sick (flu like symptoms) all the time with no particular attention paid to me by my GP or ENT. I also had an ultrasound to check my thyroid and they found many swollen lymph nodes and that the thyroid was enlarged but again said nothing to worry about. My blood tests came back all normal. Any thoughts from you would be really appreciated.
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Dr. Dong Kim in Houston, Texas. I am suffering from the same thing and a couple of other health issues. All he needs are your CT scan reports and the disc. He will look over them and do a free consultation and tell you your options and if he can help you or not. Good luck and you are not alone!! God bless!
December 1, 2015 - 12:02amThis Comment
Dear Anonymous,
Many thanks for your reply. Did you already visit him and what did he day to you? if you could send me his email address i would be really grateful i will have to send everything via email as i am from Cyprus.
December 2, 2015 - 7:26amThis Comment