Discussion in 'BioMedical ME/CFS Research' started by strategist, Nov 11, 2017.
I've asked him; I'll let you know if he responds. He may be pretty inundated just now.
Interesting comment on Phoenix Rising from a PWME who is a long-time friend of Michael VanElzakker: http://forums.phoenixrising.me/inde...athetic-harvard-researcher.56061/#post-934421
VanE spoke on this panel after the Boston screening of Unrest (starting 17:45):
I just saw this. In general, I'm not in favour of neuroimaging research into ME. At best it doesn't lead to any new treatment options; at worst, it generates misleading, false positive results that are open to misuse by the "central sensitisation" crowd.
But if there's any type of brain-related ME project I WOULD support it would be this.
The idea behind it is that the person ingests a tagged substance 11C-(R)-PK11195 before going under the scanner. This substance is preferentially taken up in brain regions where there is inflammation, and this is detected under the scanner. The scan can therefore provide a "map" of the regions where there is excessive inflammation in MECFS.
As @Simon M and @JaimeS mentioned, the Watanabe group did a previous small-scale study with interesting results, and it is definitely worth attempting to replicate what they found there. But yes, if this group already has the funding for a larger study, that's something to consider (the VanElzakker study could only include a handful of cases at that price per scan, so it would be hard to make much out of the data).
Its worth pointing out that the Nakatomi paper @JaimeS mentions is actually the same study that @Simon M is talking about (Nakatomi and Watanabe are both authors on it).
Two concerns about this research topic in general:
1. For some reason, the Nakatomi/Watanabe study picked regions of interest to examine, instead of studying the whole brain. I don't know why that is, but it is slightly concerning. The regions they picked were those most likely to be implicated in depression, emotional processing and sickness behavior, so there's kind of a hint that they consider the brain to play a causal role in ME more generally, not just in the neuro symptoms. That's a bit worrying.
I don't know whether the VanElzakker study will do the same.
2. The earlier study did not track oxygen uptake to the areas of interest. This is a problem, because people experiencing cognitive impairment may demonstrate more widespread blood flow/oxygen uptake in the brain than healthies, even at rest. If there is greater blood flow to a region, there is likely to be greater opportunity for uptake of the tagged substance. So that could be the reason for the apparent differences that Nakatomi/Watanabe found.
Ideally, you want to do get some data on oxygen uptake/blood flow as well, using either conventional PET or fMRI technology. It would be excellent if that is what VanElzakker means to do with this dual scan thing.
@Hutan, the cost of the scans is high, but that's presumably because its for dual PET (involving the tagged substance that tracks brain inflammation, which might be expensive) and MRI (presumably resting state fMRI, which is more costly than structural MRI because it takes longer to do the scan).
Still, even taking that into account, someone somewhere is making a killing on these scans. The hospital providing them perhaps?
It would be good to communicate @Woolie's points to VanElzakker, if anyone has the contacts (@JaimeS?).
Just needs someone on Twitter to ask him, one of his tweets is in the first post on this thread. @Adrian could the S4ME account do that?
SPECT scan shows the oxygen metabolism in the brain, PET the glucose metabolism (by injecting "radioactive glucose"). I hope I recalled correctly.
That PET scan publication motivated me to do a PET scan. Byron Hyde used (uses?) SPECT scans to diagnose ME.
I had a SPECT scan by Dr Hyde and it showed moderate to severe brain injuries in multiple areas of the brain.
Yeah, that's a real worry. The whole "LOOK IZ IN THE BRAINS IS PSYCHOSOMATIQUE" crowd. As far as they're concerned, the only thing the brain does is give us feelings.
Probably a better idea -- he hasn't responded to the initial email I sent him. He is in a different position, now, than when I last spoke to him, so he may not use that email address anymore.
Actually PET shows whatever you tag the positron to (positron emission tomography). That can be any molecule you like pretty much so PET can measure any biochemical process you want. In this case it is measuring binding to a ligand on the surface of microglia I think.
It is forty years since I was involved in nuclear medicine scans but my understanding is that there is a very good reason why these scans are so expensive. You have to synthesise complicated molecules that nobody might otherwise have a reason to synthesise (hence hugely expensive) and at the same time chuck in a positron emitter just before you ship the reagent out to the clinic to do the scan. it is a bit like asking Gordon Ramsay to make one of his most unusual recipes, using ingredients harvested from a remote Polynesian Island the day before, to order and ship it to the clinic steaming hot. PET scanning has been around for at least thirty years but the reagents have been so expensive to produce that it has almost never given rise to techniques that can be done in sufficient bulk to reduce the price.
Bring on the robots!
Thank you, @Jonathan Edwards, that was valuable information for me.
Again, I am astonished by the lack of knowledge of many doctors. Nobody understood the PET results (even though the radiologist had written a report), not even the neurologist. Thus, the results were called worthless (and therefore everything's fine); I guess even in court nobody would bother. Now, you say your experiences are from 40 years ago and still you seem to know more.
Personally, I think PET scans are a powerful imaging means. Would that be a wrong notion?
I would be interested in more PET study results.
As I indicated, PET scans can measure almost anything you like. 'A PET scan' is a bit like 'a blood test' or 'a cerebrospinal fluid test'. Blood tests for calcium may be very useful but blood tests for platinum levels may be a waste of time. So if you have had a PET scan the question is what it was measuring - it might have been anything. PET scans using fluorodeoxyglucose are I think the most often used - something to do with measuring metabolism of brain tissue. But it could be anything else.
Separate names with a comma.