Danger of Using SPECT Scan to Diagnose ADHD - SPECT Scan to Diagnose ADHD

Written by Thom Hartmann

SPECT Scans for Diagnosing ADHD

But with a SPECT scan, a child is injected with a radioactive material directly into his bloodstream. Its radiation-emitting particles are carried to every nook and cranny of his body. They flow into and irridadiate his developing testicles or her young ovaries and the eggs in them that will someday become children. The radiation flows with the blood into the thyroid, the uterus, pre-developing breast tissue, the adrenals, the pituitary, and even the bone marrow. Although most SPECT scannerss are only positioned to look for the "single photons" that are evoked by the detector when particles flash out of deep brain tissue, through the dura mater, through the bone of the skull, and the skin of the scalp to hit the SPECT detector, the entire body is filled with radiation.

If the SPECT scanner were put on the stomach, it would find radiation there; on the genitals, radiation there; on the feet, radiation there. "Bullets" are going off throughout the entire body - including in the child's most radiosensitive organs such as developing breast, ovarian, testicular, uterine, and thyroid tissues. And the "hit" isn't only for a fraction of a second, like it would be with an X-ray: the radioactive agent injected with a SPECT scan decays slowly, and is still detectible in the bloodstream for days after injection. (And each time one of the unstable radioactive atoms of the SPECT agent decays to something that's no longer radioactive, it emits "bullet" particles in the process, those hitting and tracking through the nearby tissues of the body at the time of breakdown.)

Lately there has been a lot of talk about the use of SPECT scans to diagnose ADHD. Of particular concern is that some physicians are using this procedure, whose risk-benefit ratio is considered acceptable for things like brain injury after a car accident or stroke (the main use for SPECT scans), on children. Children are far more susceptible to radiation-induced cancer than are adults, in part because radiation damage accumulates over time and cancers from radiation usually pop up decades after the initial exposure, and in part because their tissues are still developing and growing.

In 1997, at an ADHD conference in Israel, I had coffee with the National Institute of Health's Dr. Alan Zametkin, who had done PET scan studies (which use lower-doses of radiation) on the brains of adults with ADHD to look for differences, and whose work had recently appeared on the cover of the Journal of the American Medical Association's magazine. I asked Dr. Zametkin about the use of SPECT scans on children, and he told me flatly that he considered it both wrong and dangerous for the children.

While his PET scan studies had injected radioactive isotopes into the veins of their research subjects, they'd used a multi-million-dollar ultra-sensitive PET scanner to look for the action of the isotopes, meaning less radiation was needed to be injected than with the SPECT scan machines, which are affordable for an emergency room or doctor's office but less sensitive. (A PET scanner fills a room and is normally only found in a hospital or research facility: portable SPECT scan machines are available for emergency clinic and field use at much lower prices.) And Zametkin's studies had been done on consenting adults (not children) who were fully informed of the risks they were taking in receiving a full-body dose of decaying radiation, and who had not paid Dr. Zametkin to be in the study but were instead monitored for ill-effects from the radiation and offered other compensations.

Dr. Zametkin's perspective represents the mainstream scientific view of using nuclear medicine, particularly with children, for anything other than pure research or life-threatening illness or injury. This is probably why when Daniel Amen told Dr. Zametkin that he intended to use SPECT scans on children, Dr. Zametkin reacted negatively. To quote Dr. Amen, "He gave me an angry look and said that the imaging work was just for research: It wasn't ready for clinical use, and we shouldn't use it until much more was known about it." (Healing ADD, Amen, 2001)

Safer Brain Imaging Techniques

Of course, much is known about the effects of SPECT and PET scans. They require injecting the entire body with a continual "spray of bullets" that decay over time. Their radiation exposure doesn't last a thousandth of a second, like an x-ray, or even a few seconds like a fluoroscope: it lasts for hours, days, and traces remain for weeks. Everywhere in the body. With every single particle emitting radiation as it decays, and that radiation penetrating millions of cells on its way out of the body. While it is possible to say that "no studies have shown that SPECT scans or the radiation levels used in them cause cancer," it is a bit disingenuous: the only reason one could say that is that no such studies have ever been done. Actually, they're not necessary: there is no such thing as "purely safe" radiation, just "risk-acceptable safe" radiation in the context of the need for the procedure.

There are techniques for imaging the brain that do not require injecting people with radioactive isotopes. The best-known and most widely used is the QEEG, which measures electrical activity at over a hundred different points on the scalp and then uses a computer to create a mapped image of brain activity. These have become quite sophisticated, and involve no danger whatsoever because they're totally passive, "reading" the brain's own electrical activity instead of injecting something into the body which is then measured as it shoots back out of the body.

So the next time somebody suggests a SPECT scan for you or your child, imagine yourself standing in that hotel window, looking down at shooter on the lawn. You're a cell in your body, and the shooter is just one of the millions of particles of radioactive substance about to be injected into your or your child's vein prior to the SPECT scan.

And don't forget to duck.

About the author: Thom Hartmann is an award-winning, bestselling author of books on ADHD in children and adults, international lecturer, teacher, radio talk show host, and psychotherapist.

Read also: Study Raises Hopes for ADHD Medical Test.

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