My doctors have now told me that a little DEX to manage the pain is OK on the current medication study. DEX can also have a treatment benefit, in addition to pain relief, and I suspect that the study authors are at least slightly interested in that result too. My daily medication log will now include the DEX, if any, and the dosage.
It's working quite well - one 4-mg tab of DEX seems to last at least 30 hours before the pain returns. I've had three tabs so far, with a fourth due today if needed.
My main doctor at Mayo would also like me to come there (180 mile round trip) for another scan. In emailed messages he suggested PET/CT, but I then suggested PET/MRI if available (it's brand new), because it might provide more information about my spinal issues with less radiation exposure. I haven't heard back, but he may be checking on it. I'll do what he recommends.
I also asked for a prescription of smaller DEX tablets, perhaps 2 mg instead of 4, to see if I can get almost the same benefit with half the side effects. Maybe.
The St Croix Valley Runners are getting together for our monthly "happy hour" party at a local brew pub tonight, and I'm definitely looking forward to it. I'll bring gluten-free chips & dip.