At least I think it was helpful ... I had severe neuro symptoms and the SPECT scan showed the dr the extent of brain involvement, though I do not know how that guided the dr's treatment decisions, since I was relatively positive on the blood tests. It's a fair question to ask the dr -- 'Why is this helpful to you?' I had great insurance at the time, so cost wasn't a problem, but I recall it was pretty expensive.
I voted "still considering." Though actually my LLMD has never mentioned this test, I personally would have interest in it. It is my understanding that the SPECT scan is not the latest in brain imaging technology. For most conditions, MRI is a preferred technique. However, it is not unheard of to find a new application for an old method, and from what I have read, this is the case with SPECT scans for imaging the effects of Lyme on the brain.
As of now, I don't have any laboratory evidence that my treatment is doing anything. If (and that may be a big if) SPECT scans can monitor brain involvement before and during treatment, than I would happily consider getting the scans. Of course, cost could be an issue.
My LLMD definitely said that if insurance didn't pay for it, to not bother with it. So that says something. As wonko mentioned, neuros think it is old technology and of virtually no value.
I would get it if a doctor would order it.
Since 80% of CFS patients have abnormal SPECT scans, I've thought about having one done and even asked my specialist. His response was "why bother when you already have a diagnosis and are being treated" ?
SPECT Scan --- 80% have abnormal SPECT scans" --- Dr. Paul Cheney
source: http://www.ncf-net.org/conference/CheneyTestimony.htm