Benign Cystic Lesions of the Spine: Syringomyelia, Arachnoid Cysts, and Tarlov’s Cysts
By Dr. Wesley King, M.D.
A number of benign non-neoplastic (not related to tumors) cystic conditions can involve the spine and spinal cord. The most common are syrinx formation (syringomyelia), arachnoid cysts and perineural cysts, the latter sometimes referred to as Tarlov’s cysts.
Cavitation of the cervical or thoracic spinal cord (syrinx formation) can be an isolated problem or can be seen following trauma, including the trauma related to surgery, or can be associated with other pathological processes such as tumors or Chiari Malformations. In many cases the fluid filled cavity or syrinx may not result in any symptoms. However, enlargement of a syrinx may disrupt the neural pathways and result in progressive symptoms such as sensory changes, weakness, pain or spasticity. When severe some symptoms can be irreversible when pressure over time may lead to death of nerve cells. Treatment is directed at determining the cause of the syrinx and correcting the primary disease process if possible. In the case of Chiari Malformation, decompression of the brain abnormality usually results in resolution of the syrinx. In cases where the syrinx is an isolated finding or the result of prior trauma or surgery, it may be necessary to drain the fluid collection with a stent or shunt.
An arachnoid cyst is a cerebrospinal fluid (CSF) thin walled cyst that can involve either the brain or the spine. As with most cystic lesions, arachnoid cysts in most cases do not result in neurologic symptoms and may be incidental findings on MRI or CT. Unlike syringomyelia, these arachnoid cysts typically are located on the surface of the spinal cord, brain or nerves (extramedullary). Symptoms occur as the cyst enlarges and compressive the adjacent brain or spinal cord. Treatment in this situation may require cyst fenestration (partial removal of the wall of the cyst) to allow drainage of the CSF through the normal pathways.
When a cyst arises from the wall of a nerve it is referred to as a perineural or Tarlov’s cyst. While Tarlov’s cysts may occur at any level of the spine, they most commonly are seen in the lumbar and sacral areas. Symptoms may include leg or back pain or weakness, bowel or bladder disturbance or a change in sensation in the legs, groin or buttocks. Rupture of this type of cyst has been associated with headaches caused by low CSF pressure or even bleeding around the brain (subdural hygroma or hematoma). There are a number of treatment strategies available for Tarlov’s cysts. These include medication, injection of the cyst with “glues” or blood products (“blood patch”) and surgery.
To learn more about this disorder or to seek treatment for you, or a loved one, please see our website at http://www.neuroendo.org/ or call (310) 385-1918 today.
