The brain and spinal cord is surrounded by a special fluid called the cerebrospinal fluid, or CSF. The CSF has several different functions. One function is buoyancy, which reduces the net weight of the brain: the weight drops from 1,400 gm without cerebrospinal fluid to about 50 gm with this fluid, according to the University of Washington.
The CSF is a buffer for the brain, protecting it when there is an impact to the head. This fluid also removes harmful products and transports hormones.
In some cases, damage to the spine or the brain can result in leakage of the cerebrospinal fluid. When this occurs, the pressure around the central nervous system drops.
New York Presbyterian Hospital noted that common sites of a cerebrospinal fluid leak are in the thoracic spine and cervicothoracic junction of the spinal cord. Several conditions can result in a cerebrospinal fluid leak.
For example, a patient may develop a CSF leak after sustaining a head injury. Leakage of the cerebrospinal fluid may occur after certain medical procedures.
A leak may occur after a lumbar puncture, or spinal tap, which is a procedure in which a sample of the cerebrospinal fluid is drawn. In this case, the leakage occurs where the puncture was done.
Some patients may develop a CSF leak after having surgery on the brain, spinal cord or head. Other causes of a cerebrospinal fluid leak include cervical bone spurs, epidural anesthesia and epidural steroid injections.
A CSF leak can result in several different symptoms. Patients may have a headache, which MedlinePlus described as worsening when patients sit up, and improves when patients lie down. This headache may occur along with stiffness in the neck, sensitivity to light and nausea.
Some patients may have tinnitus, or ringing in their ears. Sensation changes may occur such as numbness in the face and tingling in the arms.
Vision changes are possible symptoms of a CSF leak, include blurry vision and horizontal diplopia, or double vision. Hearing changes may occur. While rare, draining of CSF may occur from the nose or ear.
References
University of Washington. Ventricles. Web. 26 December 2011
http://faculty.washington.edu/chudler/vent.html
MedlinePlus Medical Encyclopedia. CSF Leak. Web. 26 December 2011
http://www.nlm.nih.gov/medlineplus/ency/article/001068.htm
New York Presbyterian Hospital. Cerebrospinal Fluid Leaks. Web. 26 December 2011
http://nyp.org/health/cerebrospinal-fluid-leaks.html
Reviewed December 27, 2011
by Michele Blacksberg RN
Edited by Jody Smith