it depends on the degree of the blockage, as well as the ability of the meninges to absorb CSF. It may be that your body is still able to absorb the CSF (if it is blocking), and therefore treatment may not be necessary.

Unless you are experiencing severe headaches and vomitting I don't suggest that you insist on treatment (ie a shunt) because once a shunt, forever a shunt. Is it possible to remove part of the vertebrae to take pressure off the spinal cord? What symptoms are you having at the moment? Perhaps they can be managed effectively without a shunt or other treatment.

Nat.