Brain SPECT Imaging Research Articles
Clinical Applications of Brain SPECT Imaging in Psychiatry & Neurology
Thanks to Dr. Daniel Amen, M.D. for the following information Brain SPECT (single photon emission computed tomography) imaging is a nuclear medicine study, utilizing minute doses of radioactive Isotopes bound to neurospecific pharmaceuticals to study cerebral perfusion and thus indirectly brain metabolic activity. It has been used in the research of neurological and psychiatric disorders for the past two decades, in conjunction with PET (positron emission tomography) scanning which is a direct measure of metabolic activity. With continued improvement in technology Brain SPECT image resolution in our clinic is within the same realm as the PET scanners, although Brain SPECT imaging costs are considerably less and are more widely available.
In studying psychiatric patients with Brain SPECT Imaging researchers have found cerebral perfusion patterns that often correlate with different psychiatric conditions. The findings in this monograph stem from results obtained from over 9,000 SPECT studies done on neurological and psychiatric patients, ages ranging from 3 to 94 years old. Some of the patterns correlate with the research literature findings of PET and SPECT, some correlate with older observations from the neurosurgical, epilepsy and neurophysiological literature, and some of the findings are uniquely our own. Unlike CT, MRI and EEG which are rarely useful in the management of patients with psychiatric diagnoses, cerebral SPECT can very often be helpful in evaluating and characterizing psychiatric conditions, making treatment recommendations, and following the treatment process. Brain SPECT helps us manage psychiatric conditions in a much more efficient and informed way. Brain SPECT adds a powerful physiological tool to arrive at effective treatment options rapidly.
Normal brain SPECT Images reveal homogeneous and uniform tracer accumulation throughout the cerebral cortex, with the cerebellum being the area with the most intense activity. Chiron studied the normal progression of cerebral perfusion in children and found that by the age of 2 or 3 there is the same relative perfusion patterns as those seen in adults. Brain SPECT imaging, utilizing the radiopharmaceutical CERETEC or NEUROLITE, provides a "snapshot" of cerebral function at the time of administration of the tracer. Sedation can, therefore, be given after the dose of radiopharmaceutical without affecting the images.
Brain SPECT Patterns Frequently Found In Psychiatric, Behavioral and Learning Problems:
1. Decreased perfusion anterior prefrontal and inferior orbital prefrontal cortex
Decreased activity in the prefrontal cortex during a concentration task is often associated with impulsivity, short attention span, distractibility and difficulties with organization and planning. We have seen a strong correlation between this finding and ADHD and ADD, especially when this occurs during the performance of a concentration task. This pattern, if clinically indicated, is often responsive to psychostimulant stimulant medication. When decreased activity in the prefrontal cortex is seen during a resting state, it is often associated with depressive disorders, and may be responsive to antidepressant medication. When it is seen in both the resting and concentration states there may be a combination of depression and ADD or ADHD present. Again, clinical correlation is needed. This pattern has also been seen in response to head injuries affecting this part of the brain, and later in life in some dementia processes.
2. Decreased activity left lateral frontal area and anterior left temporal lobe
This finding is often associated with expressive language disorders. It may also be caused by head injuries to this part of the brain. If it is associated with severe mood swings and/or aggressive behavior it is often helped with anticonvulsant medication.
3. Increased activity anterior cingulate and medial frontal areas
This finding is often associated with problems shifting attention which may be clinically manifested by cognitive inflexibility, obsessive thoughts, compulsive behaviors, excessive worrying, argumentativeness, oppositional behavior or "getting stuck" on certain thoughts or actions. We have aeon a strong association with this finding and obsessive compulsive disorders, oppositional defiant disorders, eating disorders, addictive disorders, anxiety disorders (especially when combined with increased basal ganglia activity), Gilles de la Tourette’s and chronic pain. If clinically indicated, it may be helped by antiobsessive antidepressants that , increase serotonin in the brain. Certain forms of structured behavior modification techniques have also been found to help lessen activity in this part of the brain.
4. Focal increased activity lateral frontal or prefrontal cortex
This finding has been reported in ADHD or ADD. It has also been associated with seizure disorders. Clinical correlation is needed.
5. Abnormal activity left temporal lobe (either increased or decreased)
This finding may be associated with several different findings, Frequently, it is associated with mood instability, irritability, memory struggles, abnormal perceptions (auditory or visual illusions, periods of deja vu), periods of anxiety with little provocation, periods of spaciness or confusion and unexplained headaches or abdominal pain. We have found abnormalities in this part of the brain to be helped with anticonvulsant medication when clinically indicated Decreased activity in the posterior aspects of the left temporal lobes, in our experience is often, although not always, associated with learning problems, especially reading comprehension difficulties and auditory processing problems.
6. Abnormal activity right temporal lobe (either increased or decreased)
This finding is often associated with social withdrawal, social skill struggles and depression (more inwardly directed difficulties as opposed to left sided problems), If clinically indicated, it may be helped by anticonvulsant medications. When depression is present we have found imipramine to be helpful.
7. Increased basal ganglia activity
This finding is often associated with anxiety (left sided problems are often associated with irritability, right sided problems more often associated with inwardly directed anxiety). If clinically indicated it may be helped by antianxiety medications, such as buspirone and deep relaxation techniques. Sometimes if the finding is focal in nature (more one side than the other) anticonvulsant medications can be helpful.
8. Diffuse and focal Increased limbic system activity
This finding is often associated with depression, dysthymia and negativity, Left sided problems are often associated with anger and irritability, right sided problems more often associated with inwardly directed sadness. In our experience we have seen diffuse limbic overactivity tends to be more consistent depression and focal increased limbic, activity (more one side than the other) to be associated with cyclic mood disorders. When focal increased uptake is found in conjunction with patchy increased uptake across the cortical surface there is a higher likelihood of a cyclothymic or bipolar disorder. If clinically indicated, diffuse increased limbic uptake is often helped by antidepressant medications. If there is also increased anterior cingulate activity consider a serotonergic antidepressant. If there is not increased anterior cingulate activity consider an antidepressant which increases either dopamine (such as bupropion) or norepinephrine (such as imipramine or desipramine).
9. Parietal lobe increased activity
This finding often indicates hypersensitivity to noise, touch and taste. The parietal lobes have also been implicated in attentional issues. In addition, when there is bilateral parietal lobe and lateral frontal lobe activity see "ring of fire" effect below.
10. Patchy decreased or increased uptake across the cerebral cortex
Patchy decreased uptake across the cortex is often associated with toxic exposure or oxygen deprivation at some point in the past. It may also be associated with a prior brain infection, drug exposure, widespread trauma. Patchy increased uptake across the cortex is often associated with cyclic mood disorders. It may also be associated with prior toxic exposure. If clinically indicated, it may be helped by either lithium or anticonvulsant medication.
11. Focal areas of decreased perfusion
This finding is often associated with prior head trauma, turners, cysts, areas of ischemia, interictal states.
12. Focal areas of increased perfusion
This finding is often associated with ictal seizure activity or prior head trauma. Often helped by anticonvulsant medications if clinically indicated.
13. Overall decreased cerebral perfusion
This finding has been reported with depression, toxic brain exposure and in response to certain medications. Nicotine and large doses of caffeine have been associated with overall decreased cerebral per ion.
14. Flattening of the superior a anterior port of the frontal lobes
This is a finding which may be intent with prior head trauma.
15. Ring of fire pattern
This finding includes increased act activity in a left and right lateral parietal and frontal lobes and often left and right la al temporal lobes as well. Often intense increased cingulate activity is also present. This finding is often associated with mood dyscontrol, oppositional behavior, aggressiveness and irritability. It may also be related to bipolar disorder and tends to be helped with anticonvulsant medication.