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.
Myelography is an x-ray examination of the spinal canal. A contrast agent is injected through a needle into the space around the spinal cord to display the spinal cord, spinal canal, and nerve roots on an x ray. The purpose of a myelogram is to evaluate the spinal cord and nerve roots for suspected compression. Pressure on these delicate structures causes pain or other symptoms. A myelogram is performed when precise detail about the spinal cord is needed to make a definitive diagnosis.