What is Syringomyelia?
Syringomyelia is a spinal cord disorder which involves the formation of a fluid filled cyst within the spinal cord. The cyst also known as syrinx expands in size and length over a period of time leading to the destruction of the central part of spinal cord. Further expansion of the cyst compresses the nerve fibers that are responsible for carrying nerve signals from brain to lower extremities. An injury to these nerves in turn causes pain, stiffness and weakness in and around the spinal cord and the parts surrounding it.
Symptoms of Syringomyelia:
The set of symptoms experienced varies from individual to individual depending on the location of cyst formation within the spinal cord and the extent to which it has spread out. The symptoms first appear in the shoulders, back of the neck, hands and arms. The symptoms include:
- Loss of sensation in a shawl-like distribution over the upper body, shoulders and arms.
- Weakness, pain and stiffness in the shoulders, arms, back and legs.
- Loss of reflexes.
- Dysaesthesia or pain when the skin is touched.
- Muscle wasting (atrophy) and weakness.
- Loss of sensitivity to temperature and pain.
- Improper functioning of bladder and bowel.
- Facial numbness and/or pain.
- Spasms and muscle weakness in legs.
- Scoliosis or curving of the spine.
- Loss of tendon reflexes.
- Uncoordinated movement.
- Improper sweating.
- Disturbed sexual function.
The symptoms may develop gradually in most of the people.
What Causes Syringomyelia?
Cerebrospinal fluid (CSF), a protective, watery substance transports waste products and nutrients by flowing around spinal cord and brain. It also protects the brain and spinal cord to an extent by playing the role of shock absorber.
In the early developmental stages, the central canal that passes through the centre of the spinal cord is also filled with CSF.
Several medical conditions can result in an obstruction to the normal flow of CSF, leading to accumulation of it in the central canal and spinal cord. This excess fluid forms syrinx. Differences in pressure along the spine make the fluid to move in and out of the syrinx. According to physicians, this continuous movement of the fluid leads to the formation of cyst.
This medical condition could also be the result of the diseases and conditions such as
- Chiari I malformation – This usually occurs in the early developmental stages of fetus. In this condition, the lower part of the cerebellum (part of the brain) protrudes into the neck region from its original position which is the back of the head.
- Tethered spinal cord syndrome – A condition where the tissue attached to the spinal cord limits its normal movement.
- Meningitis – Inflammation or swelling of the membranes surrounding brain and spinal cord.
- Spinal Scar Tissue – Scar tissue formation after surgery.
- Spinal Cord Tumor – Tumors formed in the spinal cord may sometimes interfere with the normal flow of cerebrospinal fluid.
- Spinal Injury – Any injury caused to the spine. Symptoms may appear after several months or years after the injury.
- Arachnoiditis – Inflammation of arachnoid membrane that protects the spinal cord nerves.
- Spinal Dysraphism – Incomplete closure of the neural tube.
If this condition is not identified in its early stages and treated, it could lead to more serious complications. Moreover, some of these complications appear suddenly without any symptoms.
Complications could be a result of the enlargement of syrinx or damage to spinal cord nerves.
- Horner syndrome – A sympathetic nervous system disorder that occurs when the sympathetic nerve fibers or the nerves that travel from the brain to eye and face are damaged. Its affects are manifested on one side of the face in the form of drooping eyelid, reduced sweating on the affected side and a constricted (small) pupil.
- Motor Problems – Muscle stiffness and weakness could affect the gait eventually.
- Scoliosis – Abnormal spinal curvature.
- Chronic Pain – Spinal cord damage may cause chronic, unbearable pain.
- Permanent Disability
Forms of Syringomyelia:
Two forms of this condition have been identified.
- The most common form of this disorder is associated with the brain abnormality known as Chiari I malformation (named after the physician who first described and characterized it). Because of the relationship that was thought to exist between the brain and spinal cord in this form, it was also known as Communicating Syringomyelia. The symptoms begin to appear between 25 and 40 years of age. These may worsen by performing activities that could lead to sudden fluctuations in the cerebrospinal fluid pressure. A few patients with this condition may also have Arachnoiditis or Hydrocephalus (accumulation of cerebrospinal fluid in the brain).
- Post-Traumatic Syringomyelia – This is the second form of the disorder, which is sometimes referred to as Noncommunicating Syringomyelia. It is a result of other complications and diseases such as hemorrhage, trauma, meningitis, tumor etc. The syrinx development in this form occurs in an area within the spinal cord that has been damaged due to one of the above mentioned conditions. The cyst then expands gradually.
The first Symptom of Noncommunicating Syringomyelia is severe pain that spreads upward from the injured site. Numbness, ineffective temperature sensation and weakness on one or both the sides of the body are seen.
Syrinxes may also form in a part of the brain known as brainstem, which controls some of the important functions such as heartbeat and respiration. This type of Syringomyelia is called Syringobulbia.
Diagnosis of Syringomyelia:
Imaging is the primary diagnostic tool to detect this condition. It has helped in detecting several cases which were in the initial stages of the disorder. Magnetic Resonance Imaging (MRI) is used in diagnosing the condition. In this technique, a powerful magnetic field and computer generated radio waves produce images of brain and spinal cord in a detailed fashion.
MRI can detect the presence of syrinx and tumors if any in the spine. It also produces high resolution, 3D images of the spine. Images taken in rapid succession are usually used for ‘dynamic imaging’ to observe the flow of cerebrospinal fluid within the syrinx and around the spinal cord.
Myelogram is a test which involves the usage of a contrast medium or dye that is visible on an x-ray. The dye is injected around the spinal cord into the fluid filled space.
Computed Tomography (CT) is another diagnostic tool that reveals abnormalities such as hydrocephalus and tumors. It involves the usage of a computerized scanner and x-rays to produce cross sectional images of a particular organ or body.
Additional tests may be required in some cases. These include:
- Tests to check the pressure levels of cerebrospinal fluid.
- Electromyography – to determine muscle weakness.
- Cerebrospinal fluid analysis by puncturing the lumbar region of the spine. This process involves insertion of a hollow needle into the spinal canal and extraction of a small amount of cerebrospinal fluid.
The main aim of the treatment options is to stop further damage of the spinal cord and enhance its functioning. Although surgery is the most recommended option in majority of the patients, the type of surgery required depends on the form of Syringomyelia.
- In patients suffering from Communicating Syringomyelia, the intention behind the surgery is to provide ample space in the upper neck, at the base of the skull, without disturbing spinal cord or brain. This reduces the size of the cyst. If detected early, surgery stabilizes the symptoms in communicating syringomyelia. If delayed, it could lead to irreversible spinal cord damage.
- Shunt – Syrinx can be drained using drainage tubes, catheter and valves. This process is known as shunt. Both communicating and noncommunicating forms can be treated using shunts. In this process, soon after locating the syrinx, the surgeon places one end of the shunt inside it, with the other end draining the fluid inside the syrinx into a spacious cavity, generally abdomen. This shunt is called Syringoperitoneal shunt.
- If the cause of Syringomyelia is a tumor, surgical removal of the tumor eliminates the syrinx completely.
- Patients with Noncommunicating Syringomyelia are surgically treated by performing the operation at the ‘initial injury’ area thereby decreasing the volume of the cerebrospinal fluid by expanding the space around the spinal cord. This surgery is done outside the spinal cord.
- Another option for people with Post-Traumatic Syringomyelia is the insertion of a shunt in the syrinx by puncturing the spinal cord. But this option is considered risky due to possible spinal cord injury and replacement of the clogged shunts.
- One of the best and safest options according to surgeons is expansion of space around the spinal cord by removing the scar tissue that prevents the CSF to flow normally.
- Some patients may require the realignment of their vertebrae to correct the deformity of spine that could be narrowing the spinal column.
- Presence of a cyst in individuals who have injured their spines is common. Such cysts which are usually left untreated need to be treated only when they grow larger and start causing the symptoms.
- Drugs as a treatment option are ruled out in this condition, although pain relieving medications can be taken to ease the pain.
- Radiation is an option if presence of a tumor is detected. This option can reduce the pain and may halt the extension of the cavity.
Care after surgery is mandatory as the chances of recurrence of Syringomyelia are high.
- Regular spine examination.
- Periodic MRI scans to assess the surgery outcome.
- New syrinxes if formed need to be surgically removed.
Some Important Points:
- Shunt as a treatment option has its own risks. These include injury, blockage and infection of spinal cord or hemorrhage. Therefore, an extensive discussion with the surgeon about the pros and cons of this option is always advisable.
- Syringomyelia is not treated in the absence of symptoms.
- It may also be left untreated in individuals who do not show any progression of symptoms or in elderly people.
- Activities involving strain should be avoided by people suffering with this condition, whether treated or not.
Research on Syringomyelia:
The exact causes of this condition are not yet identified. But the scientific fraternity is exploring the mechanisms through which syrinxes are formed.
- Some physicians have observed that syrinx fluid is forced downward abruptly during heartbeat.
- Clinical studies are being conducted to understand how pressure and flow of cerebrospinal fluid contribute to the progression of the condition.
- Researchers are also looking into the genetic factors related to Chiari I malformation. Clinical studies are being conducted on patients with this malformation who have a family history of syringomyelia to identify the gene and its location responsible for Chiari I malformation.
- Understanding birth defects, especially the abnormalities in the development of hind brain responsible for Syringomyelia are being studied.
Although the proverb “Prevention is better than cure” is true for many conditions, Syringomyelia is an exception for that as there is no prevention for it. The only thing one can do is to protect their spinal cord from traumatic injuries.