Syringomyelia
Encyclopedia
Syringomyelia is a generic term referring to a disorder in which a cyst
or cavity forms within the spinal cord
. This cyst, called a syrinx
, can expand and elongate over time, destroying the spinal cord. The damage may result in pain, paralysis
, weakness, and stiffness in the back, shoulders, and extremities. Syringomyelia may also cause a loss of the ability to feel extremes of hot or cold, especially in the hands. The disorder generally leads to a cape-like loss of pain and temperature sensation along the back and arms. Each patient experiences a different combination of symptoms. These symptoms typically vary depending on the extent and, often more critically, to the location of the syrinx within the spinal cord.
Syringomyelia has a prevalence estimated at 8.4 cases per 100,000 people, with symptoms usually beginning in young adulthood. Signs of the disorder tend to develop slowly, although sudden onset may occur with coughing, straining, or myelopathy
.
normally flows in a pulsatile manner throughout the subarachnoid space
which envelops the spinal cord
and brain
, transporting nutrients and waste products. The cerebrospinal fluid also serves to cushion the brain
. Excess cerebrospinal fluid in the central canal
of the spinal cord
is called hydromyelia. This term refers to increased cerebrospinal fluid that is contained within the ependyma
of the central canal. When fluid dissects into the surrounding white matter
forming a cystic cavity or syrinx
, the term syringomyelia is applied. As these conditions coexist in the majority of cases, the term syringohydromyelia is applied. However, most physicians use the terms interchangeably.
The pulsatile movement of the cerebrospinal fluid within the subarachnoid space is a result of the phase difference in influx and outflow of blood within the cranial vault. The total fluid pulsation per cardiac cycle is approximately 1 cc in a healthy adult. Since the brain is contained within the nearly rigid cranial cavity, the cerebrospinal fluid pulsation moves into the more compliant spinal canal having nearly zero net flow during each cardiac cycle.
It has been observed that obstruction of the cerebrospinal fluid pulsation in the subarachnoid space can result in syrinx formation. A number of pathological conditions can cause an obstruction of the normal cerebrospinal fluid pulsation. These include Chiari malformation, spinal arachnoiditis
, scoliosis
, spinal vertebrae misalignment, spinal tumors, spina bifida
, and others. The reasons that blockage of the cerebrospinal fluid pulsation within the subarachnoid space can result in syrinx formation are not known. Moreover, it is unclear if syrinx fluid originates from bulk movement of cerebrospinal fluid into the spinal cord, from bulk transmural movement of blood fluids through the spinal vasculature into the syrinx, or from a combination of both. Once a syrinx has formed, pressure differences along the spine have been proposed to be one mechanism causing fluid movement within the cyst, possibly resulting in damage to the spinal cord.
.)
. This is the most common cause of syringomyelia, where the 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. Here, symptoms usually begin between the ages of 25 and 40 and may worsen with straining or any activity that causes cerebrospinal fluid pressure to fluctuate suddenly. Some patients, however, may have long periods of stability. Some patients with this form of the disorder also have hydrocephalus
, in which cerebrospinal fluid accumulates in the skull, or a condition called arachnoiditis
, in which a covering of the spinal cord—the arachnoid membrane—is inflamed.
Some cases of syringomyelia are familial, although this is rare.
, 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 (often referred to using the abbreviation of PTS) is pain, which may spread upward from the site of injury. Symptoms, such as pain, numbness, weakness, and disruption in temperature sensation, may be limited to one side of the body. Syringomyelia can also adversely affect sweating, sexual function, and, later, bladder and bowel control. A typical cause of PTS would be a car accident or similar trauma involving a whip-lash injury.
What can make PTS difficult to diagnose is the fact that symptoms can often first appear long after the actual cause of the syrinx occurred, e.g. a car accident occurring and then the patient first experiencing PTS symptoms such as pain, loss of sensation, reduced ability on the skin to feel varying degrees of hot and cold, a number of months after car accident.
and loss of sensation particularly in the hands. Some patients experience paralysis
or paresis
temporarily or permanently. A syrinx may also cause disruptions in the parasympathetic and sympathetic nervous system
s, leading to abnormal body temperature or sweating, bowel control issues, or other problems. If the syrinx is higher up in the spinal cord or affecting the brainstem as in syringobulbia, vocal cord paralysis
, ipsilateral tongue wasting, trigeminal nerve
sensory loss, and other signs may occur. Rarely, bladder stones can occur in the onset of weakness in the lower extremities.
Classically, syringomyelia spares the dorsal column/medial lemniscus
of the spinal cord, leaving pressure, vibration, touch and proprioception
intact in the upper extremities. Neuropathic arthropathy, also known as a Charcot joint, can occur, particularly in the shoulders, in patients with syringomyelia. The loss of sensory fibers to the joint is theorized to lead to damage of the joint over time.
Physicians now use magnetic resonance imaging (MRI) to diagnose syringomyelia. The MRI radiographer takes images of body anatomy, such as the brain and spinal cord, in vivid detail. This test will show the syrinx in the spine or any other conditions, such as the presence of a tumor. MRI is safe, painless, and informative and has greatly improved the diagnosis of syringomyelia.
The physician may order additional tests to help confirm the diagnosis. One of these is called electromyography
(EMG), which measures muscle weakness. The doctor may also wish to test cerebrospinal fluid pressure levels and to analyze the cerebrospinal fluid by performing a lumbar puncture
. In addition, computed axial tomography (CT) scans of a patient's head may reveal the presence of tumors and other abnormalities such as hydrocephalus.
Like MRI and CT scans, another test, called a myelogram, uses radiographs and requires a contrast medium to be injected into the subarachnoid space. Since the introduction of MRI this test is rarely necessary to diagnose syringomyelia.
The possible causes are trauma, tumors and congenital defects. It is most usually observed in the part of the spinal cord corresponding to the neck area. Symptoms are due to spinal cord damage and are: pain, decreased sensation of touch, weakness and loss of muscle tissue. The diagnosis is confirmed with a spinal CT, myelogram or MRI of the spinal cord. The cavity may be reduced by surgical decompression.
Furthermore, evidence also suggests that impact injuries to the thorax area highly correlate with the occurrence of a cervical-located syrinx.
is the only viable treatment for syringomyelia. Not all patients will advance to the stage where surgery is needed. Evaluation of the condition is often difficult because syringomyelia can remain stationary for long periods of time, and in some cases progress rapidly.
Surgery of the spinal cord has certain, characteristic risks associated with it and the benefits of a surgical procedure on the spine have to be weighed against the possible complications associated with any procedure. Surgical treatment is aimed at correcting the condition that allowed the syrinx to form. It is vital to bear in mind that the drainage of a syrinx does not necessarily mean the elimination of the syrinx-related symptoms, but rather is aimed at stopping progression. In cases involving an Arnold-Chiari malformation
, the main goal of surgery is to provide more space for the cerebellum
at the base of the skull and upper cervical spine without entering the brain or spinal cord. This often results in flattening or disappearance of the primary syrinx or cavity, over time, as the normal flow of cerebrospinal fluid
is restored. If a tumor
is causing syringomyelia, removal of the tumor is the treatment of choice and almost always eliminates the syrinx.
Surgery results in stabilization or modest improvement in symptoms for most patients. 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 patients it may also be necessary to drain the syrinx, which can be accomplished using a catheter
, drainage tubes, and valves. This system is also 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 cerebrospinal fluid
(CSF) into a cavity, usually the abdomen. This type of shunt is called a ventriculoperitoneal shunt and is particularly useful in cases involving hydrocephalus
. By draining syrinx fluid, a shunt can arrest 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 doctor and patient, as this procedure carries with it greater risk of injury to the spinal cord, infection, blockage, or hemorrhage and may not necessarily work for all patients. Draining the syrinx more quickly does not produce better outcomes, but a shunt may be required if the fluid in the syrinx is otherwise unable to drain.
In the case of trauma-related syringomyelia, the surgeon operates at the level of the initial injury. The syrinx collapses at surgery but a tube or shunt is usually necessary to prevent re-expansion.
(e.g. tramadol
and Oxycontin
respectively) combined with a medication to combat any neuropathic pain symptoms such as shooting and stabbing pains (e.g. Neurontin
or Lyrica
). In one pain management plan, an around-the-clock opiate such as fentanyl patches or Oxycontin are used in conjunction with a fast-acting opiate. However, to date no clinical trials have been published on the efficacy of these drugs in central neuropathic pain in this disorder. Trigger point injections for related muscle spasms and facet block injections may be beneficial. Long-term treatment of chronic pain should be monitored with blood tests to assess any adverse effects of the medication on the liver, with the dosages being then changed accordingly, depending on the outcome.
Drugs have no curative value as a treatment for syringomyelia. 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.
In the absence of symptoms, syringomyelia is usually not treated. In addition, a physician may recommend not treating the condition in patients of advanced age or in cases where there is no progression of symptoms. Whether treated or not, many patients will be told to avoid activities that involve straining.
Since the natural history of syringomyelia is poorly understood, a conservative approach may be recommended. When surgery is not yet advised, patients should be carefully monitored by a neurologist or neurosurgeon. Periodic MRI's and physical evaluations should be scheduled at the recommendation of a qualified physician.
Surgical techniques are also being refined by the neurosurgical research community. In one treatment approach currently being evaluated, neurosurgeons perform a decompressive procedure where the dura mater, a tough membrane covering the cerebellum and spinal cord, is enlarged with a graft. Like altering a suit of clothing, this procedure expands the area around the cerebellum and spinal cord, thus improving the flow of cerebrospinal fluid and eliminating the syrinx.
It is also important to understand the role of birth defects in the development of hindbrain malformations that can lead to syringomyelia. Learning when these defects occur during the development of the fetus can help us understand this and similar disorders, and may lead to preventive treatment that can stop the formation of many birth abnormalities. Dietary supplements of folic acid during pregnancy have already been found to reduce the number of cases of certain birth defects.
Diagnostic technology is another area for continued research. Already, MRI has enabled scientists to see conditions in the spine, including syringomyelia, even before symptoms appear. A new technology, known as dynamic MRI, allows investigators to view spinal fluid pulsating within the syrinx. CT scans allow physicians to see abnormalities in the brain, and other diagnostic tests have also improved greatly with the availability of new, non-toxic, contrast dyes.
Cyst
A cyst is a closed sac, having a distinct membrane and division on the nearby tissue. It may contain air, fluids, or semi-solid material. A collection of pus is called an abscess, not a cyst. Once formed, a cyst could go away on its own or may have to be removed through surgery.- Locations :* Acne...
or cavity forms within the spinal cord
Spinal cord
The spinal cord is a long, thin, tubular bundle of nervous tissue and support cells that extends from the brain . The brain and spinal cord together make up the central nervous system...
. This cyst, called a syrinx
Syrinx (medicine)
In medicine, a syrinx is a rare, fluid-filled neuroglial cavity within the spinal cord , in the brain stem , or in the nerves of the elbow, usually in a young age.-Etymology:...
, can expand and elongate over time, destroying the spinal cord. The damage may result in pain, paralysis
Paralysis
Paralysis is loss of muscle function for one or more muscles. Paralysis can be accompanied by a loss of feeling in the affected area if there is sensory damage as well as motor. A study conducted by the Christopher & Dana Reeve Foundation, suggests that about 1 in 50 people have been diagnosed...
, weakness, and stiffness in the back, shoulders, and extremities. Syringomyelia may also cause a loss of the ability to feel extremes of hot or cold, especially in the hands. The disorder generally leads to a cape-like loss of pain and temperature sensation along the back and arms. Each patient experiences a different combination of symptoms. These symptoms typically vary depending on the extent and, often more critically, to the location of the syrinx within the spinal cord.
Syringomyelia has a prevalence estimated at 8.4 cases per 100,000 people, with symptoms usually beginning in young adulthood. Signs of the disorder tend to develop slowly, although sudden onset may occur with coughing, straining, or myelopathy
Myelopathy
Myelopathy refers to pathology of the spinal cord. When due to trauma, it is known as spinal cord injury. When inflammatory, it is known as myelitis. Disease that is vascular in nature is known as vascular myelopathy....
.
Pathogenesis
Cerebrospinal fluidCerebrospinal fluid
Cerebrospinal fluid , Liquor cerebrospinalis, is a clear, colorless, bodily fluid, that occupies the subarachnoid space and the ventricular system around and inside the brain and spinal cord...
normally flows in a pulsatile manner throughout the subarachnoid space
Subarachnoid space
In the central nervous system, the subarachnoid cavity is the interval between the arachnoid membrane and pia mater....
which envelops the spinal cord
Spinal cord
The spinal cord is a long, thin, tubular bundle of nervous tissue and support cells that extends from the brain . The brain and spinal cord together make up the central nervous system...
and brain
Human brain
The human brain has the same general structure as the brains of other mammals, but is over three times larger than the brain of a typical mammal with an equivalent body size. Estimates for the number of neurons in the human brain range from 80 to 120 billion...
, transporting nutrients and waste products. The cerebrospinal fluid also serves to cushion the brain
Human brain
The human brain has the same general structure as the brains of other mammals, but is over three times larger than the brain of a typical mammal with an equivalent body size. Estimates for the number of neurons in the human brain range from 80 to 120 billion...
. Excess cerebrospinal fluid in the central canal
Central canal
For the engineering project, see Indiana Central Canal.The central canal is the cerebrospinal fluid-filled space that runs longitudinally through the length of the entire spinal cord. The central canal is contiguous with the ventricular system of the brain...
of the spinal cord
Spinal cord
The spinal cord is a long, thin, tubular bundle of nervous tissue and support cells that extends from the brain . The brain and spinal cord together make up the central nervous system...
is called hydromyelia. This term refers to increased cerebrospinal fluid that is contained within the ependyma
Ependyma
Ependyma is the thin epithelial membrane lining the ventricular system of the brain and the spinal cord. Ependyma is one of the four types of neuroglia in the central nervous system. It is involved in the production of cerebrospinal fluid ....
of the central canal. When fluid dissects into the surrounding white matter
White matter
White matter is one of the two components of the central nervous system and consists mostly of myelinated axons. White matter tissue of the freshly cut brain appears pinkish white to the naked eye because myelin is composed largely of lipid tissue veined with capillaries. Its white color is due to...
forming a cystic cavity or syrinx
Syrinx (medicine)
In medicine, a syrinx is a rare, fluid-filled neuroglial cavity within the spinal cord , in the brain stem , or in the nerves of the elbow, usually in a young age.-Etymology:...
, the term syringomyelia is applied. As these conditions coexist in the majority of cases, the term syringohydromyelia is applied. However, most physicians use the terms interchangeably.
The pulsatile movement of the cerebrospinal fluid within the subarachnoid space is a result of the phase difference in influx and outflow of blood within the cranial vault. The total fluid pulsation per cardiac cycle is approximately 1 cc in a healthy adult. Since the brain is contained within the nearly rigid cranial cavity, the cerebrospinal fluid pulsation moves into the more compliant spinal canal having nearly zero net flow during each cardiac cycle.
It has been observed that obstruction of the cerebrospinal fluid pulsation in the subarachnoid space can result in syrinx formation. A number of pathological conditions can cause an obstruction of the normal cerebrospinal fluid pulsation. These include Chiari malformation, spinal arachnoiditis
Arachnoiditis
Arachnoiditis is a neuropathic disease caused by the inflammation of the arachnoid, one of the membranes that surround and protect the nerves of the central nervous system, including the brain and spinal cord...
, scoliosis
Scoliosis
Scoliosis is a medical condition in which a person's spine is curved from side to side. Although it is a complex three-dimensional deformity, on an X-ray, viewed from the rear, the spine of an individual with scoliosis may look more like an "S" or a "C" than a straight line...
, spinal vertebrae misalignment, spinal tumors, spina bifida
Spina bifida
Spina bifida is a developmental congenital disorder caused by the incomplete closing of the embryonic neural tube. Some vertebrae overlying the spinal cord are not fully formed and remain unfused and open. If the opening is large enough, this allows a portion of the spinal cord to protrude through...
, and others. The reasons that blockage of the cerebrospinal fluid pulsation within the subarachnoid space can result in syrinx formation are not known. Moreover, it is unclear if syrinx fluid originates from bulk movement of cerebrospinal fluid into the spinal cord, from bulk transmural movement of blood fluids through the spinal vasculature into the syrinx, or from a combination of both. Once a syrinx has formed, pressure differences along the spine have been proposed to be one mechanism causing fluid movement within the cyst, possibly resulting in damage to the spinal cord.
Different Origins
Generally, there are two forms of syringomyelia: congenital and acquired. (In addition, one form of the disorder involves a part of the brain called the brainstem. The brainstem controls many of our vital functions, such as respiration and heartbeat. When syrinxes affect the brainstem, the condition is called syringobulbiaSyringobulbia
Syringobulbia is a medical condition when syrinxes, or fluid filled cavities, affect the brainstem. This defect normally results from congenital abnormality, trauma or tumor growth....
.)
Congenital
The first major form relates to an abnormality of the brain called an Arnold-Chiari malformationArnold-Chiari malformation
Arnold–Chiari malformation, or often simply Chiari malformation, is a malformation of the brain. It consists of a downward displacement of the cerebellar tonsils through the foramen magnum , sometimes causing non-communicating hydrocephalus as a result of obstruction of cerebrospinal fluid outflow...
. This is the most common cause of syringomyelia, where the anatomic abnormality causes the lower part of the cerebellum
Cerebellum
The cerebellum is a region of the brain that plays an important role in motor control. It may also be involved in some cognitive functions such as attention and language, and in regulating fear and pleasure responses, but its movement-related functions are the most solidly established...
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. Here, symptoms usually begin between the ages of 25 and 40 and may worsen with straining or any activity that causes cerebrospinal fluid pressure to fluctuate suddenly. Some patients, however, may have long periods of stability. Some patients with this form of the disorder also have hydrocephalus
Hydrocephalus
Hydrocephalus , also known as "water in the brain," is a medical condition in which there is an abnormal accumulation of cerebrospinal fluid in the ventricles, or cavities, of the brain. This may cause increased intracranial pressure inside the skull and progressive enlargement of the head,...
, in which cerebrospinal fluid accumulates in the skull, or a condition called arachnoiditis
Arachnoiditis
Arachnoiditis is a neuropathic disease caused by the inflammation of the arachnoid, one of the membranes that surround and protect the nerves of the central nervous system, including the brain and spinal cord...
, in which a covering of the spinal cord—the arachnoid membrane—is inflamed.
Some cases of syringomyelia are familial, although this is rare.
Acquired
The second major form of syringomyelia occurs as a complication of traumaPhysical trauma
Trauma refers to "a body wound or shock produced by sudden physical injury, as from violence or accident." It can also be described as "a physical wound or injury, such as a fracture or blow." Major trauma can result in secondary complications such as circulatory shock, respiratory failure and death...
, meningitis
Meningitis
Meningitis is inflammation of the protective membranes covering the brain and spinal cord, known collectively as the meninges. The inflammation may be caused by infection with viruses, bacteria, or other microorganisms, and less commonly by certain drugs...
, hemorrhage, a tumor
Tumor
A tumor or tumour is commonly used as a synonym for a neoplasm that appears enlarged in size. Tumor is not synonymous with cancer...
, or arachnoiditis
Arachnoiditis
Arachnoiditis is a neuropathic disease caused by the inflammation of the arachnoid, one of the membranes that surround and protect the nerves of the central nervous system, including the brain and spinal cord...
. 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 (often referred to using the abbreviation of PTS) is pain, which may spread upward from the site of injury. Symptoms, such as pain, numbness, weakness, and disruption in temperature sensation, may be limited to one side of the body. Syringomyelia can also adversely affect sweating, sexual function, and, later, bladder and bowel control. A typical cause of PTS would be a car accident or similar trauma involving a whip-lash injury.
What can make PTS difficult to diagnose is the fact that symptoms can often first appear long after the actual cause of the syrinx occurred, e.g. a car accident occurring and then the patient first experiencing PTS symptoms such as pain, loss of sensation, reduced ability on the skin to feel varying degrees of hot and cold, a number of months after car accident.
Symptoms
Syringomyelia causes a wide variety of neuropathic symptoms due to damage of the spinal cord. Patients may experience severe chronic pain, abnormal sensationsParesthesia
Paresthesia , spelled "paraesthesia" in British English, is a sensation of tingling, burning, pricking, or numbness of a person's skin with no apparent long-term physical effect. It is more generally known as the feeling of "pins and needles" or of a limb "falling asleep"...
and loss of sensation particularly in the hands. Some patients experience paralysis
Paralysis
Paralysis is loss of muscle function for one or more muscles. Paralysis can be accompanied by a loss of feeling in the affected area if there is sensory damage as well as motor. A study conducted by the Christopher & Dana Reeve Foundation, suggests that about 1 in 50 people have been diagnosed...
or paresis
Paresis
Paresis is a condition typified by partial loss of voluntary movement or by impaired movement. When used without qualifiers, it usually refers to the limbs, but it also can be used to describe the muscles of the eyes , the stomach , and also the vocal cords...
temporarily or permanently. A syrinx may also cause disruptions in the parasympathetic and sympathetic nervous system
Sympathetic nervous system
The sympathetic nervous system is one of the three parts of the autonomic nervous system, along with the enteric and parasympathetic systems. Its general action is to mobilize the body's nervous system fight-or-flight response...
s, leading to abnormal body temperature or sweating, bowel control issues, or other problems. If the syrinx is higher up in the spinal cord or affecting the brainstem as in syringobulbia, vocal cord paralysis
Vocal cord paresis
Vocal cord paresis is weakness of one or both vocal folds. Symptoms of paresis include hoarseness; vocal fatigue; mild to severe reduction in vocal volume; pain in the throat when speaking; shortness of breath; aspiration with frequent resultant coughing, and in extreme cases may cause death...
, ipsilateral tongue wasting, trigeminal nerve
Trigeminal nerve
The trigeminal nerve contains both sensory and motor fibres. It is responsible for sensation in the face and certain motor functions such as biting, chewing, and swallowing. Sensory information from the face and body is processed by parallel pathways in the central nervous system...
sensory loss, and other signs may occur. Rarely, bladder stones can occur in the onset of weakness in the lower extremities.
Classically, syringomyelia spares the dorsal column/medial lemniscus
Medial lemniscus
The medial lemniscus, also known as Reil's band or Reil's ribbon, is a pathway in the brainstem that carries sensory information from the gracile and cuneate nuclei to the thalamus.-Path:...
of the spinal cord, leaving pressure, vibration, touch and proprioception
Proprioception
Proprioception , from Latin proprius, meaning "one's own" and perception, is the sense of the relative position of neighbouring parts of the body and strength of effort being employed in movement...
intact in the upper extremities. Neuropathic arthropathy, also known as a Charcot joint, can occur, particularly in the shoulders, in patients with syringomyelia. The loss of sensory fibers to the joint is theorized to lead to damage of the joint over time.
Diagnosis
The physician may order additional tests to help confirm the diagnosis. One of these is called electromyography
Electromyography
Electromyography is a technique for evaluating and recording the electrical activity produced by skeletal muscles. EMG is performed using an instrument called an electromyograph, to produce a record called an electromyogram. An electromyograph detects the electrical potential generated by muscle...
(EMG), which measures muscle weakness. The doctor may also wish to test cerebrospinal fluid pressure levels and to analyze the cerebrospinal fluid by performing a lumbar puncture
Lumbar puncture
A lumbar puncture is a diagnostic and at times therapeutic procedure that is performed in order to collect a sample of cerebrospinal fluid for biochemical, microbiological, and cytological analysis, or very rarely as a treatment to relieve increased intracranial pressure.-Indications:The...
. In addition, computed axial tomography (CT) scans of a patient's head may reveal the presence of tumors and other abnormalities such as hydrocephalus.
Like MRI and CT scans, another test, called a myelogram, uses radiographs and requires a contrast medium to be injected into the subarachnoid space. Since the introduction of MRI this test is rarely necessary to diagnose syringomyelia.
The possible causes are trauma, tumors and congenital defects. It is most usually observed in the part of the spinal cord corresponding to the neck area. Symptoms are due to spinal cord damage and are: pain, decreased sensation of touch, weakness and loss of muscle tissue. The diagnosis is confirmed with a spinal CT, myelogram or MRI of the spinal cord. The cavity may be reduced by surgical decompression.
Furthermore, evidence also suggests that impact injuries to the thorax area highly correlate with the occurrence of a cervical-located syrinx.
Surgery
The first step after diagnosis is finding a neurosurgeon who is experienced in the treatment of syringomyelia. SurgerySurgery
Surgery is an ancient medical specialty that uses operative manual and instrumental techniques on a patient to investigate and/or treat a pathological condition such as disease or injury, or to help improve bodily function or appearance.An act of performing surgery may be called a surgical...
is the only viable treatment for syringomyelia. Not all patients will advance to the stage where surgery is needed. Evaluation of the condition is often difficult because syringomyelia can remain stationary for long periods of time, and in some cases progress rapidly.
Surgery of the spinal cord has certain, characteristic risks associated with it and the benefits of a surgical procedure on the spine have to be weighed against the possible complications associated with any procedure. Surgical treatment is aimed at correcting the condition that allowed the syrinx to form. It is vital to bear in mind that the drainage of a syrinx does not necessarily mean the elimination of the syrinx-related symptoms, but rather is aimed at stopping progression. In cases involving an Arnold-Chiari malformation
Arnold-Chiari malformation
Arnold–Chiari malformation, or often simply Chiari malformation, is a malformation of the brain. It consists of a downward displacement of the cerebellar tonsils through the foramen magnum , sometimes causing non-communicating hydrocephalus as a result of obstruction of cerebrospinal fluid outflow...
, the main goal of surgery is to provide more space for the cerebellum
Cerebellum
The cerebellum is a region of the brain that plays an important role in motor control. It may also be involved in some cognitive functions such as attention and language, and in regulating fear and pleasure responses, but its movement-related functions are the most solidly established...
at the base of the skull and upper cervical spine without entering the brain or spinal cord. This often results in flattening or disappearance of the primary syrinx or cavity, over time, as the normal flow of cerebrospinal fluid
Cerebrospinal fluid
Cerebrospinal fluid , Liquor cerebrospinalis, is a clear, colorless, bodily fluid, that occupies the subarachnoid space and the ventricular system around and inside the brain and spinal cord...
is restored. If a tumor
Tumor
A tumor or tumour is commonly used as a synonym for a neoplasm that appears enlarged in size. Tumor is not synonymous with cancer...
is causing syringomyelia, removal of the tumor is the treatment of choice and almost always eliminates the syrinx.
Surgery results in stabilization or modest improvement in symptoms for most patients. 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 patients it may also be necessary to drain the syrinx, which can be accomplished using a catheter
Catheter
In medicine, a catheter is a tube that can be inserted into a body cavity, duct, or vessel. Catheters thereby allow drainage, administration of fluids or gases, or access by surgical instruments. The process of inserting a catheter is catheterization...
, drainage tubes, and valves. This system is also known as a shunt
Shunt (medical)
In medicine, a shunt is a hole or a small passage which moves, or allows movement of fluid from one part of the body to another. The term may describe either congenital or acquired shunts; and acquired shunts may be either biological or mechanical.* Cardiac shunts may be described as...
. 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 cerebrospinal fluid
Cerebrospinal fluid
Cerebrospinal fluid , Liquor cerebrospinalis, is a clear, colorless, bodily fluid, that occupies the subarachnoid space and the ventricular system around and inside the brain and spinal cord...
(CSF) into a cavity, usually the abdomen. This type of shunt is called a ventriculoperitoneal shunt and is particularly useful in cases involving hydrocephalus
Hydrocephalus
Hydrocephalus , also known as "water in the brain," is a medical condition in which there is an abnormal accumulation of cerebrospinal fluid in the ventricles, or cavities, of the brain. This may cause increased intracranial pressure inside the skull and progressive enlargement of the head,...
. By draining syrinx fluid, a shunt can arrest 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 doctor and patient, as this procedure carries with it greater risk of injury to the spinal cord, infection, blockage, or hemorrhage and may not necessarily work for all patients. Draining the syrinx more quickly does not produce better outcomes, but a shunt may be required if the fluid in the syrinx is otherwise unable to drain.
In the case of trauma-related syringomyelia, the surgeon operates at the level of the initial injury. The syrinx collapses at surgery but a tube or shunt is usually necessary to prevent re-expansion.
Other
Surgery is not always recommended for syringomyelia patients. For many patients, the main treatment is analgesia. Physicians specializing in pain management can develop a medication and treatment plan to alleviate pain. One medication for "classical" back pain such as a weak or strong opioidOpioid
An opioid is a psychoactive chemical that works by binding to opioid receptors, which are found principally in the central and peripheral nervous system and the gastrointestinal tract...
(e.g. tramadol
Tramadol
Tramadol hydrochloride is a centrally acting synthetic opioid analgesic used in treating moderate pain. The drug has a wide range of applications, including treatment for restless legs syndrome and fibromyalgia...
and Oxycontin
Oxycodone
Oxycodone is an opioid analgesic medication synthesized from opium-derived thebaine. It was developed in 1916 in Germany, as one of several new semi-synthetic opioids in an attempt to improve on the existing opioids: morphine, diacetylmorphine , and codeine.Oxycodone oral medications are generally...
respectively) combined with a medication to combat any neuropathic pain symptoms such as shooting and stabbing pains (e.g. Neurontin
Gabapentin
Gabapentin is a pharmaceutical drug, specifically a GABA analogue. It was originally developed for the treatment of epilepsy, and currently is also used to relieve neuropathic pain...
or Lyrica
Pregabalin
Pregabalin is an anticonvulsant drug used for neuropathic pain and as an adjunct therapy for partial seizures with or without secondary generalization in adults. It has also been found effective for generalized anxiety disorder and is approved for this use in the European Union. It was designed...
). In one pain management plan, an around-the-clock opiate such as fentanyl patches or Oxycontin are used in conjunction with a fast-acting opiate. However, to date no clinical trials have been published on the efficacy of these drugs in central neuropathic pain in this disorder. Trigger point injections for related muscle spasms and facet block injections may be beneficial. Long-term treatment of chronic pain should be monitored with blood tests to assess any adverse effects of the medication on the liver, with the dosages being then changed accordingly, depending on the outcome.
Drugs have no curative value as a treatment for syringomyelia. Radiation
Radiation
In physics, radiation is a process in which energetic particles or energetic waves travel through a medium or space. There are two distinct types of radiation; ionizing and non-ionizing...
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.
In the absence of symptoms, syringomyelia is usually not treated. In addition, a physician may recommend not treating the condition in patients of advanced age or in cases where there is no progression of symptoms. Whether treated or not, many patients will be told to avoid activities that involve straining.
Since the natural history of syringomyelia is poorly understood, a conservative approach may be recommended. When surgery is not yet advised, patients should be carefully monitored by a neurologist or neurosurgeon. Periodic MRI's and physical evaluations should be scheduled at the recommendation of a qualified physician.
Research
The precise causes of syringomyelia are still unknown. Scientists at the National Institute of Neurological Disorders and Stroke in Bethesda, Maryland, and at grantee institutions across the country continue to explore the mechanisms that lead to the formation of syrinxes in the spinal cord. For instance, Institute investigators have found that as the heart beats, the syrinx fluid is abruptly forced downward. They have also demonstrated a block to the free flow of cerebrospinal fluid that normally occurs in and out of the head during each heartbeat. Duke University is conducting research to see if syringomyelia might be genetic.Surgical techniques are also being refined by the neurosurgical research community. In one treatment approach currently being evaluated, neurosurgeons perform a decompressive procedure where the dura mater, a tough membrane covering the cerebellum and spinal cord, is enlarged with a graft. Like altering a suit of clothing, this procedure expands the area around the cerebellum and spinal cord, thus improving the flow of cerebrospinal fluid and eliminating the syrinx.
It is also important to understand the role of birth defects in the development of hindbrain malformations that can lead to syringomyelia. Learning when these defects occur during the development of the fetus can help us understand this and similar disorders, and may lead to preventive treatment that can stop the formation of many birth abnormalities. Dietary supplements of folic acid during pregnancy have already been found to reduce the number of cases of certain birth defects.
Diagnostic technology is another area for continued research. Already, MRI has enabled scientists to see conditions in the spine, including syringomyelia, even before symptoms appear. A new technology, known as dynamic MRI, allows investigators to view spinal fluid pulsating within the syrinx. CT scans allow physicians to see abnormalities in the brain, and other diagnostic tests have also improved greatly with the availability of new, non-toxic, contrast dyes.
See also
- SyringobulbiaSyringobulbiaSyringobulbia is a medical condition when syrinxes, or fluid filled cavities, affect the brainstem. This defect normally results from congenital abnormality, trauma or tumor growth....
- Central cord syndromeCentral cord syndromeCentral cord syndrome is an acute cervical spinal cord injury that can affect a large and diverse group of patients. It was first described by Schneider in 1954....
- Dissociated sensory lossDissociated sensory lossDissociated sensory loss is a pattern of neurological damage caused by a lesion to a single tract in the spinal cord which involves selective loss of fine touch and proprioception without loss of pain and temperature, or vice-versa....
- EpendymomaEpendymomaEpendymoma is a tumor that arises from the ependyma, a tissue of the central nervous system. Usually, in pediatric cases the location is intracranial, while in adults it is spinal. The common location of intracranial ependymoma is the fourth ventricle...
tumors - ScoliosisScoliosisScoliosis is a medical condition in which a person's spine is curved from side to side. Although it is a complex three-dimensional deformity, on an X-ray, viewed from the rear, the spine of an individual with scoliosis may look more like an "S" or a "C" than a straight line...
is sometimes caused by syringomyelia. - Otto KahlerOtto KahlerOtto Kahler was an Austrian physician. Born and trained in Prague, he is best known for describing multiple myeloma, a hematological malignancy, which is called "Kahler's disease" in his honor in several countries...
was a neurologist from the last 1800s who published the first complete description of syringomyelia. - Bobby Jones, a famous golfer, was diagnosed with tumor-related syringomyelia in 1948.
- Brown-Sequard SyndromeBrown-Séquard syndromeBrown-Séquard syndrome, also known as Brown-Séquard's hemiplegia and Brown-Séquard's paralysis, is a loss of sensation and motor function that is caused by the lateral hemisection of the spinal cord...
External links
- Mayo Clinic's page
- Living With SM and CM Community Site
- Washington University School of Medicine - Link provided courtesy of Christopher S. Burton Syringomyelia Foundation's Research Team