Outcome from treatment for spinal arteriovenous malformation.

Our knowledge of the outcome from treatment for spinal arteriovenous malformations (AVMs) is limited to a few small, anecdotal series and is thus far from complete. Furthermore, with the recent rapid evolution of our knowledge of AVM pathology, many reported cases are difficult to place in the current classification system. In general, outcome for the four classifications of AVMs are as follows: type I respond well to surgical disconnection of the arteriovenous fistula if treatment is early; type II AVMs are currently best treated by surgery but risks of a poor outcome need to be carefully considered; type III are only rarely treatable; type IVa and IVb are likely to respond well to surgery but our knowledge is limited; and type IVc are likely to fare poorly from surgery but should have a better outcome from endovascular therapy.