What is Tarlov Cyst or Perineural Cyst?
Tarlov cyst or perineural cyst is a special category of cysts which is found in the sacral region i.e. the base of the spine. Tarlov cyst or perineural cyst are the sacs filled with fluids. Tarlov cyst or perineural cyst are formed near at the nerve roots of the spine. The number of tarlov cyst or perineural cyst can be more than one and vary is sizes. Tarlov cyst or perineural cyst are hard to detect as they are mostly asymptomatic i.e. does not show any symptoms. The symptoms for tarlov cyst or perineural cyst are not very specific and vary according to the location and the size of the tarlov cyst or perineural cyst.
Generally, the symptoms of tarlov cyst or perineural cyst reveal themselves with the increase in the size of the cyst. An individual having tarlov cyst or perineural cyst would show one or more of the following symptoms: Impotence, inability to control bladder and bowel movements (incontinence), numbness and altered sensation etc. As the tarlov cyst or perineural cyst affects the nerves, the area served by the nerves would show signs of pain. In a very few cases the symptoms may include weakness in legs. Small tarlov cyst or perineural cyst would rarely show any symptoms but as they grow larger, the symptoms start to get pronounced. Researchers are still searching for the precise cause of tarlov cyst or perineural cyst but initial studies suggest that it may be caused due to abnormal development of nerve sheath.
Most of the cases of tarlov cyst or perineural cyst remain undiagnosed, as there are no early symptoms. Professionals and doctors can detect tarlov cyst or perineural cyst only by using the imaging techniques. The temporary solution of draining the tarlov cyst or perineural cyst can only provide instant relief, which does not last long. For the permanent removal of symptoms and avoiding the tarlov cyst or perineural cyst to repeat in future, surgery is only the perfect option. Ignoring the symptoms and leaving the tarlov cyst or perineural cyst untreated can cause permanent damage to the neurological system.
What is a Tarlov Cyst or Perineural Cyst on the Spine?
Tarlov cyst or perineural cysts are categorized into the list of type II innervated meningeal cysts. The tarlov cyst or perineural cyst are filled with the cerebrospinal fluid (CSF). Mostly the sacs are formed in the spinal canal of the S1-to-S4 region, which is the part of spinal cord.
Can Tarlov Cyst or Perineural Cyst Cause Back Pain?
Tarlov cyst or perineural cyst may be associated with the back pain. As the cyst grows larger, the particular nerve root where it is located starts to get affected which result in sharp pain with burning sensation around the hip and thigh region on the back possibly along with the weakness and lack of sensation in the respective leg and foot. In some worst cases, the tarlov cyst or perineural cyst may get large enough to cause weathering of the bone on the surrounding, which may result in back pain.
Generally, tarlov cyst or perineural cyst are not a major issue and does not need any treatment. However, if there are some serious symptoms, the cysts can be drained out with surgeries to provide complete relief. As there are, only a few cases of tarlov cyst or perineural cyst, studies and researches in this field are limited and vague.
Who May be Involved in the Management of a Patient with Tarlov Cyst or Perineural Cyst?
A person suffering from tarlov cyst or perineural cyst can seek treatment from any neurosurgeon or interventional neuro radiologist. However, the doctor or the physician must be an expert in the field of symptomatology of the tarlov cyst or perineural cyst and the fields related to treatment of cysts to ensure proper treatment and optimum results. The specialists in the field of pain management are very helpful in case of tarlov cyst or perineural cyst. Professional physicians can help to manage the symptoms like the inability to control bladder and bowel movements. In some cases where the individual faces any issues related to bladder like frequent infection in urinary tract or incontinence, urinary retention etc. should consult a good urologist.
Causes of Tarlov Cyst or Perineural Cyst
The true causes for tarlov cyst or perineural cyst are still a mystery. Some studies suggest that possibly the some sort of inflammation in the nerve root sheath are the cause of cysts. According to some other theories, any type of trauma can affect the root sheath and cause it to release cerebrospinal fluid leading to cysts formation. As the sacs are filled with CSF, many researchers feel that it has something to do with the abnormal communication between the subarachnoid space containing CSF or cerebrospinal fluid and perineural region. Possibly, disruption of the flow after the leakage of CSF or cerebrospinal fluid can be the cause of cyst formation. Any increase in the CSF or cerebrospinal fluid pressure can push more CSF into the sacs making them grow in size, which results into symptoms.
It has been observed in many cases that any trauma or some specific situations, which cause increases CSF pressure, can cause the symptoms to appear in case of asymptomatic tarlov cyst or perineural cyst. Some studies have reported that disorders in connective tissues make individuals more prone to tarlov cyst or perineural cyst.
Surely, there is a need of much more research to determine the actual causes and the mechanisms behind the cause of tarlov cyst or perineural cyst and the symptoms.
Signs and Symptoms of Tarlov Cyst or Perineural Cyst
In most of the cases, tarlov cyst or perineural cyst are symptomatic i.e. tarlov cyst or perineural cysts are present without any symptoms. Only when the size of the tarlov cyst or perineural cyst gets larger, an individual can feel some symptoms because of the damaging effect on associated roots due to excessive pressure. The symptoms of tarlov cyst or perineural cyst can vary from one individual to another depending on the location and size of the tarlov cyst or perineural cyst.
The most common symptom in case of symptomatic tarlov cyst or perineural cyst is chronic pain. Tarlov cyst or perineural cyst located around lumbosacral would generally show symptoms of pain in the portion starting from lower back and extend down further to legs. Continuous movement like walking may increase the pain. Constantly sitting or standing for long time can also put stress and cause more pain. In such situations, lying back in a relaxed position is helpful. Tarlov cyst or perineural cyst located in the upper spine will show symptoms like pain in the upper half of the body including neck, arms, upper back etc. Coughing and sneezing can further increase the pain. Some other symptoms for tarlov cyst or perineural cyst are testicular, vulvar, pelvic, abdominal and rectal pain.
As the cyst formation in tarlov cyst or perineural cyst takes place near nerve root, there are clear symptoms of damage to neurological functioning like weakness in legs, weaker reflexes, lack of sensation in skin, malfunctioning of bladder and bowel causing painful urination also referred as dysuria. Tarlov cyst or perineural cyst can also cause constipation, inability to empty bladder completely, impotency etc…
Further, there are signs of pickling and burning sensation (paresthesias), lack of sensation and numbness in legs and feet. The specific part of the spine affected by TCs may show signs of soreness and tenderness.
Other symptoms of tarlov cyst or perineural cyst are one or more of the following: pressure behind the eyes, chronic headaches, dizziness, blurred vision, weakening of muscles of foot and ankle forcing an individual to drag, weathering of spinal bone around the cyst etc…
Tests to Diagnose Tarlov Cyst or Perineural Cyst
There are few tests available for diagnosing tarlov cyst or perineural cyst. It is not easy to be certain about tarlov cyst or perineural cyst just based on the symptoms because many other types of cysts and tumors show huge similarities as compared to tarlov cyst or perineural cyst in terms of symptoms. Meningoceles, meningeal diverticula, neurofibromas, arachnoid cysts and schwannoma, all similar types of symptoms as observed in tarlov cyst or perineural cyst.
Thus, an expert needs to evaluate an individual based on comprehensive clinical tests, study the patient history to observe particular symptoms and perform complete neurological examination to be certain about tarlov cyst or perineural cyst. There are some specially designed tests to diagnose a patient for tarlov cyst or perineural cyst. Sometimes, tarlov cyst or perineural cysts can be found while a patient undergoes X-ray or MRI scan for any other possible reason.
Clinical Testing and Work Up for Tarlov Cyst or Perineural Cyst
Magnetic resonance imaging (MRI) is generally performed for lumbar region to diagnose a patient for tarlov cyst or perineural cyst. Computed tomography (CT) is equally effective in detection of tarlov cyst or perineural cyst. MRI is the part of the latest technology in which magnetic fields are used to generate a graphical 3D image of the particular organ being scanned. CT scan is another technology, which makes use of X-rays to draw cross-sectional images for examination.
Myelogram is advanced form of X-ray examination, which makes use of the contrast material, which is a special type of dye to get clearer images. In this test, the contrast material is injected into the spinal canal to make the nerve roots more highlighted and visible when observed under X-rays or in CT scan. In the next step, CT scan is performed to observe for the location and size of the tarlov cyst or perineural cyst. Myelogram can also be used to determine any type of erosion in the vertebral bone.