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Tuesday, September 21, 2010

SPECT Scans: Serious Skepticism is in Order.

SPECT.  By now, you may have seen it on TV or in one of many self help books by Dr. Daniel Amen. Over the last decade, SPECT has been made popular by Dr. Amen. He has marketed his ideas about the usefulness of SPECT to mental health providers and to the general public, through seminars and popular TV shows like Oprah and PBS.

If you are not familiar with SPECT, it's stands for, Single Photo Emission Computed Tomography. It is a form of nuclear medicine, where a radioactive tracer is injected into your bloodstream and a machine then scans the brain in order to reveal degrees of oxygen consumption in areas of the brain. A computer translates the information from the SPECT scan into a recognizable image. 

I was one of those therapists who trusted what Dr. Amen had to say, until the last year or so, I've grown very skeptical of his conclusions and ideas about the meaning of SPECT images. Briefly, Dr. Amen explains that SPECT tell us three things: which parts of the brain "work well," which parts of the brain "work too hard" and which parts of the brain "do not work hard enough." And, "the goal of treatment is to balance brain function, such as calm the overactive areas and enhance the under active ones."

Please allow me to reflect on a professional continuing education seminar I attended 3 or 4 years ago, where Dr. Amen was the presenter. The title of his seminar was something like, "neuroscience for frazzled clinicians." This title seems to imply that he has the answers. His seminar was convincing. It seemed clear, logical, and most importantly, scientific. For about 2-3 years I was enthused about SPECT. I had referred a few clients for SPECT evaluations. There was one client in particular where I thought the results were revealing and helpful; however, there were two others where it was essentially useless, where SPECT had offered no additional information for diagnosis and treatment. One client in particular was left with more questions than answers, and this was frustrating for both of us.

What really put me over the edge with SPECT, was when scientists were studying the Amygdala (uh-mig-duh-la) of a fish (the amygdala is a primary emotional center of the brain, common to most vertebrates). They scanned the head of the fish after presenting it with fearful objects, and sure enough, the fish's Amygdala was bright red, indicating that it was very "active." There was only one problem, the fish was dead, stone, cold dead. The problem that the scientists identified was that the computer program that translated the SPECT scan to into a readable image, was improperly programmed.

I realized that SPECT had limitations, but how much? What occurred to me, through these experiences was that Dr. Amen never mentioned problems with SPECT as I had experienced. Looking back through his materials, he has very little to say about the limitations or cons of SPECT. Dr. Amen had done thousands of SPECT scans; why hadn't he shared negative or problematic outcomes where SPECT provided no useful information or unclear, confusing information? I reviewed his most popular book, Change Your Brain Change Your Life; there's no mention, that I could see, of the drawbacks or limitations of SPECT.

In the last year, I have spent more time reading original research and critiques about SPECT as well as other types of nuclear imaging for neuroscience, including fMRI, MRI, CT, and PET. There's three problems that with nuclear imaging as they related to the diagnosis and treatment of mental health problems:

(1) Radiation exposure: All forms of nuclear medicine expose you to radiation. For example, SPECT uses technetium-99m, which emits Gamma radiation and it uses a Gamma ray scanner - this may increase your chances of brain cancer by an unknown percentage; the younger you are when you have such a scan, the greater the increase in your lifetime risk. Repeated exposures may substantially increase your cancer risk. For example, a CT scan of your abdomen is equivalent to 450 x-rays and may increase your lifetime cancer risk by an entire percentage point, if you are 5 years old at the time of the CT scan. Multiple CT scans, may then increase your cancer risk exponentially. One-percent may not sound like much, but that's a statistical calculation. There's no real way to know how a CT or SPECT will impact your own personal cancer risk.

(2)  Cost. Nuclear medicine is expensive, and the cost may continue to rise, especially since the technology becomes more popular. The reason is because the type of nuclear materials used are presently becoming more scarce, and as demand increases, the cost may increase. For example, a SPECT scan might cost $3,500 for an initial, and about $800 to $1,500 for follow-up scans. Insurance companies may not cover these costs.

(3) Most importantly, SPECT cannot inform us about Cause and Effect. This is what I found most problematic about SPECT scans. If you find one part of your brain is "less active" in relation to the rest of your brain, or in relation to a "normal" brain, this does not mean that this less active part of the brain is the cause of your mental illness; in fact, it could be that this less active part of the brain was caused by something else or by many factors. What psychiatrists like Amen seem to be doing is what they've been doing for the last fifty years - trying to reduce complicated mental health problems to the most simple terms of cause and effect (please read my post on this blog about the Chemical Imbalance myth).

I recall an anecdote of Dr. Amen's from his book, Change Your Brian Change Your Life: he was working with a couple who he described as "stuck." He prescribed an SSRI and found that they became unstuck and their relationship improved. Perhaps that was the case. But there's no mention of the drawbacks of medications, the impact of weight or sex life, and dependency. There are many other techniques to help couples and individuals work through these problems without pointing to pictures of their brains, without side effects, and where people can really learn what they need to learn in order to change their life.

In other words, perhaps the wife in that couple was stuck for a more complicated reason that Dr. Amen couldn't see, but that a trained psychotherapist could see. Marital relationship are complicated. Perhaps this person's brain was "more active" in one part because she was using that part of her brain more than the rest, because she was coping with chronic marital problems.

An interesting fact is that psychotherapy techniques, when used by people, lead to observable changes in a person's brain, just like medications can do; sometimes these changes are in different parts of the brain, sometimes the same. The brain is extremely complicated, with about 100 Billion nerve cells with 100 Trillion connections, affected by over 200 unique groupings of nerves, over a dozen types of nerve cells, and over two dozen types of chemicals which impact it's functioning. Good luck!

At this point, SPECT should be saved for research and for a diagnostic aid in complicated cases of mental illness. But, the overwhelming majority of Americans do not need SPECT imaging for diagnosis or treatment of their mental health or behavioral health problems.

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Okay - so, as I'm writing this post, my mother calls me, she's in her 80's. She says, "Scott, do you know who Dr. Daniel Amen is?" "Why yes, I was just thinking about him," I say. She says, "Well, he was just on PBS, and he said something like, 'if you have low cholesterol you may be at increased risk of suicide or homicide' " (My mother has heart disease and has been taking cholesterol lowering medication for years, and now she has low cholesterol, so hearing a doctor on PBS allege that she's at increased risk for suicide or homicide, well, freaked her out).

This is the problem with television and popular psychiatry - they make dramatic statements that have only a grain of scientific basis. There's probably one or two studies out there, with 12 or so participants, where some had suicide or homicide behaviors and low-cholesterol. One or two studies on 10 or 12 people never determine cause and effect, especially for the general population. I reassured my mom that suicide and homicide are the last things she needs to be worrying about, and that having low cholesterol probably has nothing to do with your suicide or homicide risk.

This is another example of trying to reduce a complicated behavior (suicide) to a simple cause (low-cholesterol). Suicide is an extremely complicated problem. There are dozens of major risk factors for suicide. Low cholesterol is probably not a risk factor; taking cholesterol lowering medications probably isn't either, but I can't say either way, and neither should anyone else, because there's just not enough research. There are also many protective factors, which help keep people from committing suicide. If someone told me that they had low-cholesterol, I would tell them that they should sleep well, knowing that they have a lower risk for one of our most common killers: heart disease.


Mental Health Advice Disclaimer

The information included in this post and blog are for educational purposes only. It is not intended nor implied to be a substitute for professional mental health treatment or medical advice. The reader should always consult his or her mental health provider to determine the appropriateness of the information for their own situation or if they have any questions regarding a mental health or medical condition or treatment plan. Reading the information on this website does not create a therapist-patient relationship.

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