Exercise-induced asthma is a condition of respiratory difficulty (bronchoconstriction) that is related to histamine release,is triggered by aerobic exercise, and lasts several minutes. Causes include medical conditions, environmental factors, and medications. The image below illustrates the pathogenesis of asthma.
A myelogram is an invasive diagnostic test that uses x-rays to examine the spinal canal. A special dye is injected into the spinal canal through a hollow needle. An x-ray fluoroscope then records the images formed by the dye. Myelograms can show conditions affecting the spinal cord and nerves within the spinal canal.
A myelogram may be done to assess the spinal cord, subarachnoid space, or other structures for changes or abnormalities. It may be used when another type of exam, such as a standard X-ray, does not give clear answers about the cause of back or spine problems. Myelograms may be used to evaluate many diseases, including: Herniated discs (discs that bulge and press on nerves and/or the spinal cord)