car accident). Pathogenesis The pathogenesis of syringomyelia is debated. The cerebrospinal fluid also serves to cushion the brain. Excess cerebrospinal fluid in the central canal of the spinal cord is called hydromyelia. This term refers to increased cerebrospinal fluid that is contained within the ependyma of the central canal. When fluid dissects into the surrounding white matter forming a cystic cavity or syrinx, the term syringomyelia is applied. As these conditions coexist in the majority of cases, the term syringohydromyelia is applied. The terms are used interchangeably. It has been observed that obstruction of the cerebrospinal fluid spaces in the subarachnoid space can result in syrinx formation, and alleviation of the obstruction may improve symptoms. A number of pathological conditions can cause an obstruction of the normal cerebrospinal fluid spaces. These include Chiari malformation, spinal arachnoiditis, scoliosis, spinal vertebrae misalignment, spinal tumors, spina bifida, and others. The reasons that blockage of the cerebrospinal fluid space within the subarachnoid space can result in syrinx formation are not fully understood although a small posterior fossa is one known cause. It is unclear if syrinx fluid originates from bulk movement of cerebrospinal fluid into the spinal cord, from bulk transmural movement of blood fluids through the spinal vasculature into the syrinx, or from a combination of both. Recent work suggests that central nervous system compliance is the underlying problem for the central nervous system, and also that hydrocephalus and syringomyelia have related causes. Diagnosis Physicians now use magnetic resonance imaging (MRI) to diagnose syringomyelia. The MRI radiographer takes images of body anatomy, such as the brain and spinal cord, in vivid detail. This test will show the syrinx in the spine or any other conditions, such as the presence of a tumor. MRI is safe, painless, and informative and has greatly improved the diagnosis of syringomyelia. The physician may order additional tests to help confirm the diagnosis. One of these is called electromyography (EMG), which show possible lower motor neuron damage. Note this test isn't used diagnostically for injuries to the spine but to nerves and muscles.This would be part of a patients rehab routine. In addition, computed axial tomography (CT) scans of a patient's head may reveal the presence of tumors and other abnormalities such as hydrocephalus. Like MRI and CT scans, another test, called a myelogram, uses radiographs and requires a contrast medium to be injected into the subarachnoid space. Since