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.
For example, myelodysplastic syndrome is a type of cancer in which the bone marrow cannot make enough healthy blood cells. Abnormal cells appear in the blood as a result of myelodysplastic syndrome, and these unhealthy cells leave less room for healthy blood cells in bone marrow.