How a SPECT Scan Works
A SPECT scan is conducted in the nuclear medicine department of a hospital and involves the use of a radioactive tracer that is injected into the patient. The cost of the treatment varies between hospitals, as does the cost of interpreting the results. In most cases the cost of a SPECT scan is not covered by health insurance as it is considered an experimental procedure unnecessary for Lyme disease diagnosis or treatment. Checking for approval prior to undergoing the test is vital for patients who are unable to afford the SPECT scan themselves. The test itself takes about an hour to carry out but does not involve the patient lying in a ‘tunnel’ as with Lyme disease MRI. A second test may be carried out a few days after the first using a drug called acetazolamide (Diamox) to increase blood flow in the brain. This second test can help to determine if an earlier abnormal scan was the result of impaired blood flow or neuronal degeneration. Patients with certain conditions should not be administered Diamox, including: those who are pregnant; patients with kidney disease or liver disease; those with electrolyte abnormalities; recent stroke patients; patients with a sulphur allergy; and those taking high aspirin doses.
Interpreting SPECT Scans
The interpretation of the SPECT scan can affect treatment for a condition such as Lyme disease and may, in fact, lead to the recognition of misdiagnosis and a change in treatment strategy for an illness such as fibromyalgia, chronic fatigue syndrome, or even spinocerebellar degeneration. ‘Holes’ in the map of blood flow in the SPECT scan are considered to represent areas of hypoperfusion (low blood flow), which may be caused by inflammation in the brain caused by spirochaetes such as Borrelia. The ischaemic action of such inflammation prevents the radioactive dye from being distributed in these areas which is why they show up as black holes on the SPECT scan. Areas of the brain that are deprived of blood are also deprived of oxygen and glucose and their function suffers with impacts on the production of neurotransmitters such as dopamine and serotonin. Dysfunction in the brain, and low levels of neurotransmitters may be responsible for some of the cognitive symptoms of Lyme disease such as mood irregularities, poor concentration, and amnesia.
Follow-Up SPECT Scans Post-Treatment for Lyme Disease
In cases where patients respond well to antibiotic treatment of Lyme neuroborreliosis, a second SPECT scan may be free of these black ‘holes’ showing that there have been improvements in blood flow in the brain. This test may provide some level of reassurance then for a patient that treatment has had an effect, and may allow them to pursue alternative therapy for any symptoms which remain. The SPECT scan is expensive, and with many patients already struggling with medical fees for chronic Lyme disease treatment it may simply be out of reach without help from health insurers. Until the scan is proven to be an effective component of Lyme disease diagnosis and treatment however, it is likely to remain uncovered by health insurance. Patients are also recommended to exercise caution when given advice on the basis of a SPECT scan to undergo experimental treatments such as stem cell treatments for Lyme disease.
Continue Reading –> Efficacy of SPECT Scan for Lyme Disease