Hi and welcome to the Chiari forum.
Sorry NO, decompression surgery does not stop the symptoms, what it does do is stops progression of the condition especially if there is an obstruction and it opens up the blockage....this can alleviate some symptoms and over time you may see more benefits.....it really depends on not only what Dr you choose to use, but what other conditions you may have in addition to Chiari....it seems it never travels alone.
I had the surgery 9 years ago, and am very happy with my results and benefits....it did take time for me to see all the benefits I did have since it is not all at once, or wasn't for me.
I have no doubt whatsoever that most if not all of us here would love to tell you "Yes, the symptoms just go away after surgery". But sadly it just isn't so. My former NS explained it this way. He said that in many cases the nerve damage in the brain stem is already done. In some cases the brain has already learned from years of feeling certain sensations that they are normal so you continue to feel them. No doubt the severity of these symptoms is directly related to exactly how compressed your brain stem was among other things. The alternative to surgery [with those who need it as not everyone does] is watching your symptoms continue to deteriorate. For me personally "would I go through it again? Absolutely with the right doctor"
Before my surgery I often could not walk 10 feet without feeling migraine or dizziness, and struggled to use stairs as my balance was horrific. I was told that the surgery would not be the cure to chiari, but probably would help me go about my daily life. I was at the point where literally anything was better than suffering as much as I had, and 10 years later I can genuinely say it has really helped me. I still get loads of my old symptoms, but my balance is now better, and my co-ordination is also so much better, rather than living in a constant migraine state, I'd maybe get 3 headaches a week, which is something I can control. Hope this helps :)
No, there is no absolute certainty with decompression surgery. What I DO know is that it helped me tremendously. I still have some symptoms from time to time after 6 years, but I don't regret decompression surgery one iota. I agree with Selma, it really depends on who your surgeon is and whether there are other issues that go along with your CM.