Posted by manowar on December 3, 2001, at 22:57:55
In reply to Re: SPECT imaging has its place in psychiatry, posted by SLS on December 1, 2001, at 9:46:49
> > Tim,
> >
> > Could you explain a little about the science/technology involved with a SPECT scan? It seems that a controversy has been unearthed here that we don't have all of the facts displayed regarding..physics-chemistry-what is going on, i.e. I remember when I went for my cardiac stress test a few months ago. I saw something in the radiology department that seemed to related to what you are discussing. The stuff I saw (info-pamphlet-publication from GE) appeared to be about radiolabeling dextroamphetamine and injecting it. Then they do a "scan" showing where the brain is using the d-amphetmaine the least or most. Is this accurate?
> >
> > Mitch
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> Matter + Antimatter = annihilation > positron
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> - ScottHi Scott,
I'm glad you mentioned that procedure. I had forgotten about it. When I first met my new "ADD doctor", he was very excited about the scans that I had gotten at the Amen clinic. My scans though, were for testing overall brain function, which is different from the testing that you're talking about. He told me that a SPECT procedure was being developed that could help pdocs and neurologists clearly diagnose ADD in patients. (There is no clear scientific method that exists yet) He had done some research on that procedure and yes, it involves giving a patient a dose of some kind of dopamergic drug (I can't remember if it was dextroamphetamine), which was radiolabled. I can't remember for sure, but I think that doctors look at the scan to see how large the area is in the brain that takes up the drug. I think he told me that scientist hypothesized that people with ADD have too many dopamine receptors.Anyway, the next time I see him I'll ask him more about it and post it on this site. The research is supposed to be very promising.
All I can do is give you a layman answer to the way my procedure was done. It may not be very accurate, but here goes:
1) Injected with a radioisotope that binds with glucose in the blood. (Glucose is not injected; the radioisotope binds with the glucose that is naturally in the blood already.)
2) You're put on a table and you're pushed into a tube that surrounds you're head.
3) For about 15 minutes the tube rotates. There are cameras inside the tube taking x-ray pictures of the isotope (which is binded with the glucose). It-very effectively- in essence is measuring the uptake of glucose, which is necessary for all cells to function (hence- functional image)
4) A computer takes the data and creates different types of 3D images
5) The images give doctors an idea of how the different parts of the brain are functioning.The supposed advantages of a SPECT scan to psychiatry are that:
1) A doctor does not have to totally rely on symptomology (which is not always accurate or definitive) to diagnose a condition
2) Therefore, if there is a more accurate diagnosis, a more accurate treatment regimen can be prescribed to help a patient
3) When presented with more information, hopefully a patient is more likely to comply with the treatment regimen
Hope that was helpful,
Tim
poster:manowar
thread:85484
URL: http://www.dr-bob.org/babble/20011202/msgs/85933.html