Brain Scans, Part 2
According to Dr. Amen, SPECT can do more than show who has ADHD. He says it can identify which of his six ADHD "subtypes" a person has. Each subtype requires its own kind of treatment, claims Dr. Amen.
He describes one of his patients, a boy from Atlanta, who had been diagnosed with ADHD. "When he was put on stimulants, he picked his skin and was frightened at bedtime." SPECT showed a pattern of over- rather than underactivity, Dr. Amen says. "He had a hot, not a cold, brain. It wasn't appropriate for stimulants. I put him on a handful of supplements, including fish oil, to calm his brain rather than stimulate it, and he did much better."
Michael Uszler, M.D, a nuclear medicine specialist who heads a clinic in Santa Monica, California, occasionally performs SPECT scans on children referred to him by pediatricians and family physicians. He agrees that SPECT cannot be used to make a final diagnosis, but that it adds to the picture presented by examination and other tests.
Researchers have also found distinctive brain patterns in ADD by using qEEG, which, like SPECT, is available in clinics across the country. Unlike SPECT, qEEG uses no radiation; a layer of gel is applied to the head to conduct electrical impulses, and the patient dons an electrode-studded cap. For each scan, the patient must remain very still for about 20 minutes, and several scans are customary. The cost varies by location, but $500-$900 for a full evaluation is not unusual.
Daniel Hoffman, M.D., a Denver-based neuropsychiatrist, often uses qEEG to confirm a diagnosis of ADHD and to determine which medication to prescribe. "About 35 percent of the people we see who were diagnosed with ADD don't seem to have the neurophysiology for it. And most clinical research shows that about the same number don't respond to stimulants. I think these are the same people."
Brain wave patterns, like the blood flow images produced by SPECT, reveal abnormalities in the frontal area of the brain. Some patients with ADHD symptoms have an excess of slow waves, while others have too much fast-wave activity, according to Dr. Hoffman. "On the surface, you can't tell them apart," he says. "They have the same symptoms. qEEG shows the cause of the symptoms."
By comparing a patient's qEEG to a database derived from thousands of drug trials, Dr. Hoffman says he can better predict which ADHD medication will be the most effective. "The more I use this," he says, "the more I realize I was shooting in the dark without it."
Skeptics and believers
Few ADHD experts consider SPECT a particularly useful tool in diagnosing or treating ADHD. The work of people like Dr. Amen, many experts say, has not been available for the scrutiny of the scientific community, and his findings haven't been duplicated by the research of others - a basic criterion of scientific validity.