Kristie Brady's Medical consultation for Syringomyelia

Syringomyelia (sear-IN-go-my-EEL-ya) is a disorder in which a cyst forms within the spinal cord.  This cyst, called a syrinx, expands and elongates over time, destroying a portion of the spinal cord from its center and expanding outward.  As a syrinx widens it compresses and injures nerve fibers that carry information from the brain to the extremities.  Damage to the spinal cord often leads to progressive weakness in the arms and legs, stiffness in the back, shoulders, arms, or legs, and chronic, severe pain.  Other symptoms may include headaches, a loss of the ability to feel extremes of hot or cold (especially in the hands), and loss of bladder and other functions.  Each individual experiences a different combination of symptoms depending on where in the spinal cord the syrinx forms and how far it extends.  Signs of the disorder tend to develop slowly, although sudden onset may occur with coughing or straining.

What causes Syringomyelia?

A watery, protective substance known as cerebrospinal fluid (CSF) normally flows around the spinal cord and brain, transporting nutrients and waste products.  It also acts as a cushion to protect the brain and spinal cord.  In early development, CSF also fills a small canal that runs through the center of the spinal cord"”the central canal"”which then collapses normally over time.

A number of medical conditions can cause an obstruction in the normal flow of CSF, redirecting excess fluid into the spinal cord and central canal.  This redirected CSF accumulates within the tissue of the spinal cord and forms a fluid-filled syrinx.  Pressure differences along the spine cause the fluid to move within the syrinx and outside the spinal cord.  Physicians believe that this continual movement of fluid in and around the spinal cord results in cyst growth and further damage to the spinal cord tissue.

Kristie's diagnosis:

In the course of Kristie's diagnosis, it was discovered she has a benign tumor in her brain called a meningioma. It's very likely this is the cause of the disruption of the flow of CSF fluid around her brain and spinal cord. It was also discovered that in front of the tumor there is a subarachnoid cyst where there is no brain matter, just CSF fluid.

In the vast majority of cases, neurosurgeons are extremely reluctant to operate to remove meningiomas because they grow very slowly and in 95% of the cases they are not malignant. Howver, we believe in Kristie's case that the size and location of the menigioma is causing the disruption of the CSF flow and has been the primary reason three (3) syrinxes have formed in her spinal cord.

What causes Syringomyelia?

Generally, there are two forms of syringomyelia.  In most cases, the disorder is related to an abnormality of the brain called a Chiari I malformation, named after one of the physicians who first characterized it. 

This anatomic abnormality causes the lower part of the cerebellum to protrude from its normal location in the back of the head into the cervical or neck portion of the spinal canal.  A syrinx may then develop in the cervical region of the spinal cord.  Because of the relationship that was once thought to exist between the brain and spinal cord in this type of syringomyelia, physicians sometimes refer to it as communicating syringomyelia. 

Symptoms usually begin between the ages of 25 and 40 and may worsen with straining or any activity that causes CSF pressure to fluctuate suddenly.  Some individuals, however, may have long periods of functional stability.  Some people with this form of the disorder also have hydrocephalus, in which CSF accumulates in the brain, or a condition called arachnoiditis, in which a covering of the spinal cord"”the arachnoid membrane"”is inflamed.

The second major form of syringomyelia occurs as a complication of trauma, meningitis, hemorrhage, a tumor, or arachnoiditis.  Here, the syrinx or cyst develops in a segment of the spinal cord damaged by one of these conditions.  The syrinx then starts to expand.  This is sometimes referred to as noncommunicating syringomyelia.  Symptoms may appear months or even years after the initial injury, starting with pain, weakness, and sensory impairment originating at the site of trauma.

The primary symptom of post-traumatic syringomyelia is pain, which may spread upward from the site of injury.  Symptoms, such as pain, numbness, weakness, and disruption in temperature sensation, may occur on one or both sides of the body.  Syringomyelia can also adversely affect sweating, sexual function, and, later, bladder and bowel control.

Treatment:

Surgery is usually recommended for individuals with syringomyelia.  The type of surgery and its location depend on the type of syringomyelia. 

In the case of Chiari malformation, the main goal of surgery is to provide more space at the base of the skull and upper neck, without entering the brain or spinal cord.  This results in the primary cyst becoming much smaller.  Surgery results in stabilization or modest improvement in symptoms for most individuals with Chiari malformation.  Delay in treatment may result in irreversible spinal cord injury.  Recurrence of syringomyelia after surgery may make additional operations necessary; these may not be completely successful over the long term.

In some individuals it may be necessary to drain the syrinx, which can be accomplished using a catheter, drainage tubes, and valves.  This system is known as a shunt.  Shunts are used in both the communicating and noncommunicating forms of the disorder.  First, the surgeon must locate the syrinx.  Then, the shunt is placed into it with the other end draining the syrinx fluid into a cavity, usually the abdomen.  This type of shunt is called a syringoperitoneal shunt.  A shunt of CSF from the brain to the abdomen is called a ventriculoperitoneal shunt and is used in cases involving hydrocephalus.  By draining syrinx fluid or CSF, a shunt can halt the progression of symptoms and relieve pain, headache, and tightness.  Without correction, symptoms generally continue.

The decision to use a shunt requires extensive discussion between the surgeon and the individual, as this procedure carries with it the risk of injury to the spinal cord, infection, blockage, or hemorrhage and may not necessarily work for all people.

If a tumor is causing syringomyelia, removing the tumor is the treatment of choice and almost always eliminates the syrinx.

In the case of trauma-related syringomyelia, the preferred surgical approach is to operate at the level of the initial injury to expand the space around the spinal cord and decrease fluid volume.  This operation is performed outside the spinal cord. 

An alternate operation is to place a shunt in the syrinx, which requires a hole to be made in the spinal cord.  Shunts may injure the spinal cord and may require replacement if they clog over time.  Many surgeons now consider shunt placement only as a last resort.  Instead, surgeons usually choose to expand the space around the spinal cord.  This is done by removing scar tissue that "tethers" the cord in place and prevents the free flow of CSF around it, and adding a patch to expand the "dura," the membrane that surrounds the spinal cord and contains the CSF (a procedure called expansive duraplasty).  In some cases, the vertebrae may need to be realigned to correct spinal deformity that is narrowing the spinal column.

Many spinal cord-injured individuals have a cyst at the site of the original injury.  These cysts do not always require treatment, although treatment may be warranted if a cyst grows larger or begins to cause symptoms.

Drugs have no curative value as a treatment for syringomyelia but may be used to ease pain.  Radiation is used rarely and is of little benefit except in the presence of a tumor.  In these cases, it can halt the extension of a cavity and may help to alleviate pain.