Bruce,
Is your tumor on the same side as the spasms? If so, I think there is a serious possibility that this is simply related to the dying process that your tumor is undergoing in response to CK treatment.
In my experience, CK doctors are pretty clueless when it comes to post-treatment symptoms. I suspect this is because this tumor we have consists of organic matter and is moving around and touching all this sensitive nerve stuff, triggering strange and crazy sensations in our head. The doctors really have no way of knowing fully what exactly the tumor is touching, with how much pressure, etc.
I had CK at Stanford in August 2007 for a 2.6 cm right-side AN. I had some right-side facial numbness before treatment. Since treatment, I have experienced various sorts of weird sensations on the right side of my face, from a feeling a numbness to the occasional tick to the occasional urge to scrunch up that side of my face to increase sensation. There's some weird stuff with my right eye too. For me, months 2 - 8 after treatment were the most intense in terms of post-treatment symptoms. Dr. Chang and the team at Stanford would tell me, on the several occasions that I called in frustration at how crappy I was feeling, that this is the period where we are most intensely feeling the effects of the radiation. In fact, I was told that intense symptoms relatively early on after treatment could be a positive sign that the tumor is responding well to the treatment, i.e., it is dying. In my case, my six month MRI revealed that my tumor had become substantially inflamed from the radiation but also appeared very much on its way to necrosis. Now, about nine months out, nearly all of my post-treatment symptoms (and they were quite unpleasant at times) have faded.
It sounds like your spasms are much more intense than anything I experienced in my face but I share all this because, let's be honest, we have a tumor in a sensitive part of the body, surrounded by nerves that control movement and sensation in our face, and the tumor is undergoing some intense responses to a blast of radiation. My experience has been that a lot of these sensations settle down with time after CK. I sincerely hope the same happens in your case.
Best,
Francesco