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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The cyst is killing me. Misdiagnosed with cerebellar hypoplasia by the NIH. Cerebellum is compromised...I have syringobulbia as a DX and no one told me this...just found it in my file. No one will do surgery. Begging for ten years. Progressing. I am likely going to die from this and hope those reluctant surgeons pay some how. Good luck and God speed to anyone with this, diagnosed or not.
December 12, 2016 - 5:36pmThis Comment
I feel the same exact way. I am suffering from constant seizures. I have speech problems, memory loss and behavioral changes. I just want these cysts removed.
April 1, 2017 - 10:38pmThis Comment
Dear Anonymous,
March 16, 2017 - 1:28pmAn arachnoid cyst in the posterior fascia was found in my daughter's head before birth. (7 month sonogram) To make a long story short, God delivered an angel to us. His name is Dr. Saadi Gahtan from Mt. Sinai hospital in New York City. He saved my daughter's life. She is healthy and well at 12 years old. Reach out to him. You can just put his name in Google and it comes right up. I pray you get in touch with him. I know he can help you. I cant say it enough, the man is an absolute angel on earth.
This Comment
My daughter was also saved by another angel at Mt. Sinai hospital. That was two years ago. She is now 36 and doing well. Just pray constantly her shunt never clogs.
March 16, 2017 - 2:52pmThis Comment
I was originally from New York. I wish I still lived in New York. The best doctors are all in New York. My daughter was very sick when she was five, I moved back to New York and she got the best care. I moved from Arizona to Ohio and I am getting care at the cleveland clinic. I am afraid the doctors here are as useless as in Arizona. I am so tired of suffering anyway, should have never left New York.
April 1, 2017 - 10:46pmThis Comment
I am 39yr old dignosed with a posterior fossa cyst 5cmx1cmx4cm on the left cerebellum with mildly diplaces my cerebellum. My symptoms are bilateral hand numbness, head pressure which increases with walking and supine, I see floaters, have ringer in my ears and leg weakness. My family MD says the symptoms are not related, the internist said he had no idea. The neurologist says the symptoms are most likely from the cyst. I am seeing a neurosurgeon in January. All I can say is you really have to advocate for yourself!
December 11, 2016 - 3:39pmThis Comment
Did you receive the surgery and did you get better?
August 11, 2017 - 7:10amThis Comment
Hello I have a cyst on the right side of the posterior cranial fossa it is displacing the right cerebellar hemisphere posteriorly it' measures 1.5cm x 1.5cm x 3.5cm I was just wondering how you got on after seeing the neurosurgeon as I am waiting to here off one to see what can be done thanks
July 17, 2017 - 9:41amThis Comment
Two years and three months after surgery I am able to function very well. I only experience headaches before a rainstorm or snowstorm. Not showers but a real storm. My walking is better, no more vertigo, no more numbness, no more vomiting, and I can ride the train to work again. My arachnoid cyst now drains into my spine as they were unable to remove it because of its location. It caused my brain to have hydrocephalus. I am now out of danger but require an MRI once a year to check the drain and the cyst. Surgery saved me!!!!
July 17, 2017 - 2:53pmThis Comment
I just read the post someone sent you that had no hope. My daughter was operated on two years ago at age 34 for her arachnoid cyst. Because the cyst got so large everything in her brain was being compromised...her arteries were hardly allowing blood to flow. Her internist said it was back problems. I insisted she get a script for an MRI and that is when they found the arachnoid cyst. Twelve days later she was operated on at Mt Sinai hospital in NYC. The operation was a success. Her symptoms prior to surgery were similar to yours. Recoup was hard but now her symptoms are mild and she says she feels like her life is back. Try to see a surgeon in a big city where they are more likely to have experience with this. My prayers are with you...there is hope out there...be persistent and do not give up.
December 13, 2016 - 4:59pmThis Comment