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Date of last update: 10/21/2017.

Forum Name: Brain Tumors

Question: Arachnoid Cyst?

 jurollo - Fri Feb 02, 2007 1:17 pm

I am a 30yr. old female and have been extremly ill since the end of July 2006. I have tested positive for Mono and RMSF since then. I was sent to the U of U Medical Center for the ID Specialist. She had no way to test to see if I had active mono or previous infection and the RMSF showed past infection. I have had an MRI of the brain with the findings as follows:
Posterior to the right cerebellar hemisphere is a sharply demarcated oval extra-axial cyst (2 x 1cm) which follows CSF attenuation/signal pattern. Following contrast no enhancement visible. Brain parenchymal pattern shows multiple small deep white matter hyperintensities also within the basal ganglia bilaterally. Left maxillary sinus shows (1.5cm) smoothly outlined cyst with high T2 signal.
Interpretation: Posterior right cerebellar extra-axial fluid collection following CSF signal intensity. Findings compatible with an arachnoid cyst with other etiologies much less common. Rarely this might represent some type of neurenteric cyst.
Left maxillary sinus cyst.
Also on a CT of my abdomen I showed a small (5mm) cyst on the left kidney lower pole.
Are these cyst related? Could they be making me so ill? (Headache, nausea, pain, can't stand loud or mutiple noises, locking jaw, eye twitching, extreme fatigue, etc...) How serious is an arachnoid cyst and what other etiologies could it be? What is a neurenteric cyst? Is the deep white matter and basal ganglia hyperintensities related to the cyst?
Any help would be deeply appreciated!!! My first physician only mentioned my sinus cyst, said it was benign and not to worry, I had to request my results and found the arachnoid cyst on my own. The Infectious Disease Specialist seemed concerned by the MRI results.
 Dr. Chan Lowe - Sun Mar 18, 2007 8:32 pm

User avatar I am only able to comment on a few of the findings.

First, the arachnoid cyst is unlikely to be causing your symptoms. They are generally benign, incidental findings-even when quite large.

The cyst of the kidney is also likely to be an incidental finding. An occasional renal cyst is relatively common.

As for the other findings on your MRI, I am unable to comment. I am not familiar with what this may indicate.

I hope this helps a little.

Best wishes.

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