Syringomyelia (SM) is a disease in which there is a syrinx, or cyst, in the spinal cord. The syrinx is filled with cerebrospinal fluid (CSF). Due to normal activities like coughing and straining, SM cavities can slowly become larger over a period of time, often years. As the syrinx gets larger, it stretches the spinal cord and damages nerve tissue. Damage to nerve tissue can result in serious and/or disabling symptoms.
Syringomyelia can also be known as hydromyelia. CM causes most cases of SM. Up to 50 percent of CM patients also develop SM. CM can block the normal flow of CSF, which forces the fluid into the spinal cord, creating the fluid filled syrinx.
Types of syringomyelia
The type of SM a patient has depends on the cause. There are two main types:
- those caused by Chiari
- those caused by disease of the spine
Birth defects, tumors, injuries, infections or past surgeries are the most common causes of these diseases of the spine. Past spine surgery can cause SM due to the growth of too much scar tissue. There also is a small chance that SM can be caused by placing a foreign liquid in the spinal canal.
Symptoms of syringomyelia
Symptoms of SM usually happen slowly over time. However, a fall or minor trauma can make the symptoms of SM appear more quickly.
Motor symptoms
- weak and shrinking muscles, mostly in hands and arms
- stiff and spastic muscle tone in arms and/or legs
- abnormal curvature of the spine (scoliosis)
Sensory symptoms
- decreased feeling in hands and arms, with the legs possibly being affected depending on size and place of the syrinx cavity
- exaggerated sensation (hypersensitivity) in limbs, mostly in the arms
Pain symptoms
- midline pain over the spine, particularly the trunk area
- burning pain in arms, over trunk and, rarely, legs
- joint pain, usually in the shoulders
Sphincter problems
- total or partial loss of bladder control, sometimes a spastic feeling of the bladder
- total or partial loss of bowel control
- male impotence
Symptoms of involuntary body functions (body functions our brain controls without us thinking about it, such as breathing)
- wide swings in blood pressure, often accompanied by profuse upper body sweating, both involuntary body functions collectively known as dysreflexia
- drooping of one eyelid
- fainting or nearly fainting, a rare condition called syncope
- commonly worse on one side of the body.
Diagnosing syringomyelia
MRI can clearly show the presence of a syrinx in the spinal cord. A neurological exam is used to decide the impact the syrinx is having on the nervous system.
Surgery for syringomyelia
If CM is thought to be the cause of the SM, neurosurgeons most often will do a Chiari decompression surgery, then watch to see if that brings about a collapse of the syrinx. If the Chiari surgery does not collapse the syrinx, the patient might need surgery for the syrinx. The incision for a syrinx can be at any point in the back of the neck or upper back. It depends on the location of the syrinx cavity.
Prognosis for syringomyelia
Researches do not have exact data on the prognosis for syringomyelia. Much depends on the patient's health and the presence of other conditions before surgery. Up to 80 percent of patients will experience some level of relief or at least not get worse. About 20 percent will get worse. Most patients will have some lasting symptoms even after surgery, so major lifestyle changes may be needed. Severe, constant pain, which can be difficult to treat, is one of the most common long-term problems. Recovery can be very slow and can involve many setbacks. Living with SM can have a major effect on patients and their families.