is a sist in the pineal gland of the brain bad =(?

It’s cyst, not sist, and yes, that can be bad. There’s an article by a guy with a brain cyst here, if you want to read about it:
http://www.bbc.co.uk/dna/h2g2/A602876

cyst aren’t necessarily bad
but finding one on the pineal must have been difficult since that gland is the smallest in the body
i’m curious how it was detected !!!!
i want that technology at my hospital !

i found this for you:
A pineal gland cyst is a cyst in the pineal gland, a small endocrine gland in the brain.. Statisically, these fluid-filled bodies appear on 1-4% of magnetic resonance imaging (MRI) brain scans. They are in most cases asymptomatic, and it is rare for a pineal cyst to cause symptoms. If they do, these would most likely be headache, visual disturbances, or hydrocephalus, which can be extremely dangerous if left untreated. Pineal cysts are not cancer and most of the time they do not enlarge over 2 centimeters.
Asymptomatic cysts require no treatment. Some doctors choose to monitor patients with CT scans or MRI to look for cyst growth, but most doctors do not{{fact|date=June 2007)).
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The above information was found in a journal article, “High Prevalence of Pineal Cysts in Healthy Adults Demonstrated by High-Resolution, Noncontrast Brain MR Imaging” by Y. Pua, S. Mahankalia, J. Houa, J. Lia, J.L. Lancastera, J.-H. Gaoa, D.E. Appelbaumb and P.T. Fox.
Published ahead of print on September 20, 2007 doi: 10.3174/ajnr.A0656
American Journal of Neuroradiology 28:1706-1709, October 2007 © 2007 American Society of Neuroradiology
Weblink: http://www.ajnr.org/cgi/content/full/28/9/1706