Q.How consistent are the results from day-to-day?
A. The paper by Villanueva-Meyer, Javier, M.D., et al. elegantly answers this question, showing that there is less than 3% variability in SPECT scans over time for the same activity.3 Our own clinical experience – scanning people sequentially and sometimes 12 years apart – is that SPECT patterns are the same unless you do something to change the brain. SPECT is a reproducible and reliable method for sequential evaluation.
Q.What is normal?
A. In the SPECT literature over the past 34 years, there have been more than 59 studies looking at normal issues in over 4,111 patients; including more than 300 children from birth on (see http://www.amenclinics.com/the-science/research-tables/normal-research/ for references and more information). Plus, there are normal areas in almost all of our nearly 100,000 scans. In addition, we have scanned many normal people. Normal scans show full, even, symmetrical activity, with the cerebellum being the most active area of the brain.
Q. Some physicians say, “I don t need a scan for diagnosis, I can tell clinically.” Is this true?
A. Often, well-trained physicians can tell the diagnosis clinically, but without a scan they can never know the underlying brain pattern or physiology.
Q. Should I be concerned about the radiation exposure, especially in children?
A. The average radiation exposure for one SPECT scan is 0.7 rem, similar to a nuclear bone scan or brain CAT scan, and is considered a safe procedure, according the guidelines established by the American Academy of Neurology.4 These other procedures are routinely ordered for many common medical conditions (i.e. bone fractures or head trauma), further suggesting that the levels of radiation exposure are generally acceptable in medical practice. Ineffective treatment of psychiatric illness poses more risk than the low levels of radiation associated with a SPECT scan.