A spinal tap is a medical procedure that is known as a lumbar puncture. It is used for diagnosis by draining some of the cerebrospinal fluid that is present in the spinal cord right up to the brain. The cerebrospinal fluid is the fluid that is surrounding the brain and the spinal cord. It dulls the effect of any physical jerk or injury that occurs and is thus the physical shock absorbing system for the brain. The cerebrospinal fluid also allows the brain to be buoyant within the skull, thus eliminating any pressure that might fall on blood vessels under the weight of the brain. The cerebrospinal fluid also helps to maintain the chemical balance in the brain and the spinal cord.
This fluid is diagnostically relevant. When the fluid is drawn from a puncture in the back, it is sent to a laboratory for analysis. During the analysis and discoloration will be noted. This discoloration can point to one or many conditions. The chemical analysis of the fluid is also done to measure the glucose, protein and lymphocyte levels. All these levels when compared with each other are useful to diagnose a condition that may be affecting the brain, the spinal cord or the fluid itself. The cerebrospinal fluid is also measured when there is an increase in intracranial pressure which may be caused by an inflammation or by an infection. In some rare cases, a spinal tap is used to relieve this pressure by removing some of the fluid, thereby relieving the pressure.
There are risks associated with this procedure. Generally, patients may report nausea after such a test is performed. This is avoided by maintaining a still position after the test or through medication. Sometimes, there will be odd sensations in a patient's leg if the needle being used in the spinal tap touches the nerves causing a disruption in the signal sending and receiving process. If the test is conducted during a condition of high intracranial pressure, a sudden removal of the fluid may cause rapid reduction in pressure which can be dangerous to the brain. If the puncture is not perfect, there is a chance that there might be some infection that occurs around the area of the tap, which, if serious, may infect the cerebrospinal fluid. Rare cases may cause paralysis; but this is extremely unlikely unless the patient has jerked violently during the procedure causing a rupture in the spinal cord.More articles from the Medical Tests Category