Opening of Dura During Cranio Cervical Decompression

Hi - can anyone explain or refer me to reading up on:  

why is the dura opened up during surgery and where exactly is it opened up - on the cerebellar tonsils/on the brainstem/on the cord?  Have actually had the op July last year (have a Chiari 1 and Syrinx in my cord), but it's a question I do keep wondering about and can't seem to find the exact answer to.  I know that the op is done with the aim of producing more space, but what's the purpose of opening of the dura?  Where does the CSF actually flow through when it goes around the brain and the cord?  Thanks.

[Spaceystac]

Hi, I will try and help you understand to the best of my knowledge.
  So obviously you understand it is the blockage of csf flow that caused the issues with the Chiari malformation. The malformation its self is caused my the cerebral tonsils blocking that flow due to their downward displacement due to the lack of space.  So opening the dura is to shrunk the tonsils in most cases, this is needed in combination with the decompression. Many people have a cauterization if the tonsils and some surgeons remove them other ways. This part of the brain is believed to not have function any more and that it is a part of the brain that was turned off as we evolved thousands of years ago note: this is one theory I read on the function of the cerebral tonsils.
They can also add a dural patch to open up the space the dura has around the brainstem and cord so that they are less likely to have to further operations in the future, they wanted to make sure there was enough room, when you have a syrinx it is most important to open the flow blockages to hopefully shrink your syrinx.

Csf flows around and circulates, it comes out in ventricles and absorbs in a different area. It s purpose is to protect the nervous system from impacts and it washes away waste products that the brain and cord tissue but off after the use the nutrients that the fluid brings to the cns system.  You might want to google image search csf flow, it will help you understand this a bit better.


Hope this helps, any more questions fell free to ask, Have a nice day  Stacey.