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NBIA FAQ >>> |
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Diagnosing Patients |
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The diagnosis of
NBIA is sought by using
specialized imaging techniques (CT scan and MRI) that demonstrate the characteristic
accumulation of large amounts of pigmented material in certain areas of the brain
(globus
pallidus and pars reticulata of the substantia nigra). These areas of the brain
appear to have a brownish discoloration when viewed with these imaging techniques.
Localized swelling of tissue is also evident, especially in those areas that affect the
function of the central nervous system. One test that may be useful for the diagnosis of
NBIA measures the uptake of radioactive iron (ferrous citrate) into certain areas of the
brain. Unusually high uptake is characteristic of this disease. While the diagnosis may be first suspected from the uncontrolled movements, these are not sufficient to allow the diagnosis to be made. Physicians will usually look for features that allow them to understand the cause of the movement problems, since many conditions can have dystonia as a feature. Often an eye examination by an ophthalmologist (a physician expert in eye health and disease) reveals the characteristic pattern of pigment deposits in the "seeing" portion of the eye called the retina. This finding of pigmentary retinopathy is common in NBIA, but it can also be seen in more than fifty other conditions. In addition, many people with NBIA do not develop this eye change. While there may be no problems with vision early on, often a person with pigmentary retinopathy (or retinitis pigmentosa) will eventually develop tunnel vision and very poor night vision. Genetic testing for the PANK2
gene mutation, responsible for approximately 50% of those diagnosed
with NBIA, is now available at The University of Chicago Genetic Services
Laboratories. They can be reached at their toll free number in the United
States, (888) 824-3637, or their local number (773) 834-0555. Their web
site address is www.genes.uchicago.edu.
You can also send an e-mail message to ucgslabs@genetics.uchicago.edu.
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