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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Maryann Gromisch RN thanks for answering my question..Yeah i m under treatment but my echo,urine , blood and ultrasound everything is normal..no cause of hypertension has come i m very confused..
November 12, 2015 - 2:47amRerference
patient of arachnoid cyst + blood pressure
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I have also an arachnoid cyst with high blood pressure around 150/100 ..is there any connection of arachnoid cyst with high blood pressure ..?? as my age is 20 years..
November 2, 2015 - 1:21amThis Comment
Hello Anonymous,
Are you under a physician's care to treat your high blood pressure? That is a dangerously high reading, especially for a 20 year old.
The exact cause of a primary arachnoid cyst is unknown — it develops in a fetus during pregnancy, but nobody knows why. Secondary cysts can be caused by trauma (a fall, accident, or other injury), illness (meningitis or brain tumor), or as a complication of brain surgery.
In most cases, arachnoid cysts are present at birth, so I do not think there is a correlation between the development of an arachnoid cyst and hypertension, which is not normally seen in infants. Talk with your doctor about this.
Regards,
November 9, 2015 - 9:18amMaryann
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There is so little known but it is possible. My daughter had brain surgery for her arachnoid cyst and chiari malformation in April. She is 34 and prior to surgery had high blood pressure and now her pressure is normal. Who knows whether it was the cyst? She was diagnosed two days before surgery. She had problems for about a year but ignored them all and doctors even told her it was back problems. Thank God she had an MRI or she might not be here today. Good luck and look for a good neurologist who has experience with arachnoid cysts.
November 6, 2015 - 6:36pmThis Comment
My name is Ivan I am 25 years of age and I have this cyst on the left side of my brain ranging from my ear to the start of my left eye, its 8.6 cm in length and 4.4 cm in width. I have neglected the fact I have had this because my neurosourgon told me I need to get it sucked out becauss it has pushed my left brain 3 mm to the right side. Im not sure when I have gotten or if it has anything to do with my behaviour. I am a nice person but sometimes I have very unusual thoughts and get very angry quick. Let me know if anyone has something to share . I'm sitting at the hospital waiting for another scan to see if has changed in size.
March 30, 2015 - 10:29amThis Comment
I just got my Brain MRI back. Doc thought I had an acoustic neuroma but none was seen.
March 24, 2015 - 7:15pmIncidental note is made of a midline posterior fossa cyst of about 3 cms, congenital variation.
I still dont think I have a cyst. I got fired last week for uttering obscenities to a customer. Surprised myself at the time. Tinnitus in right wear interferes with my ability to play the piano as it is so distorted I cannot stand to play it for long.
I have an apointment with a head surgeon in 2 days to discuss the results of my MRI.
Been having short auras (30 minutes) with a somewhat sick pain nothing really bad. Consider myself a complete failure at life with 15 years university and 4 maybe five degrees up to PhD that I have to drive a taxi cab for a living. Im not a demon.
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You reported:
Incidental note is made of a midline posterior fossa cyst of about 3 cms, congenital variation.
You have a cyst. Medical fact.
Yet, you went on to state that you do not believe that you have a cyst.
You do indeed have a cyst.
October 19, 2015 - 3:00pmThis Comment
update:
March 26, 2015 - 1:15pmDr said it was nothing to be concerned about.
Thats it.
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I was also diagnosed with a cyst in the back of my brain. They found it after they ordered an MRI for my brain because I complained about dizziness, also when I turn my head I hear my pulse and if the room is dark I will see flashes along with the pulsing I hear. All of this is right after my back started feeling better from a car accident and I stopped taking my tramadol and tizanidine. After the medicine wore off and my back pain was manageable with out the meds, I start feeling the dizziness and the pulsing and flashing. Never experienced these symptoms before and I am really scared. But I have started taking them again because the symptoms go away when I do.
March 19, 2015 - 10:43pmThis Comment
My name is Jess and I am also from Texas experiencing similar issues. For about 9 months i've been getting horrible never-ending headaches almost daily, especially when I need to use my eyes a lot (At work, driving, ect.) I feel like everything is off kilter and distant like you said (Very Spacey). My hearing and vision gets really clouded and it gets hard to focus. My headaches usually start toward the end of the day and the pain is usually right above my eyes and lasts for several hours. Accompanied with that is a lot of dizziness, vertigo, nausea, and fatigue. I feel like it's almost impossible to keep my eyes open and stay awake.
I have an arachnoid cyst in my middle crania fossa which is pretty large, but the doctor refuse to operate unless they can prove 100% that the symptoms are associated with the cyst. Has anyone else experienced a similar issue? I feel like it has to be coming from the cyst because all I feel is constant pressure and weakness. I feel like at least draining the cyst would greatly reduce the symptoms and I'm willing to try anything at this points.
March 9, 2015 - 12:29pmThis Comment