What are the other Names for this Condition? (Also known as/Symptoms)

• Nerve Root Cyst
• Perineural Cyst

What is Tarlov Cyst? (Definition/Background Information)

• Tarlov Cyst is a benign slow-growing tumor that usually forms around the lower part of the spinal cord. These cysts are commonly observed in young and middle-aged adults. A high incidence is seen in women
• Tarlov Cyst is an extraneural (outside the nerve) cyst containing neural tissue and filled with cerebrospinal fluid (CSF), most commonly occurring in the nerve root sheath. Hence, this cystic tumor is also known as a Nerve Root Cyst
• The exact cause of formation of a Tarlov Cyst is unknown. According to current research, it may develop as a result of trauma or inflammation of the nerve root sheath. In some cases, it is associated with certain connective tissue disorders such as Marfan and Sjögren syndromes
• Small-sized Tarlov Cysts may not present any significant signs and symptoms; however, large and symptomatic cysts may cause lower back pain, numbness, weakness of the lower extremities, or loss of bladder/bowel control
• The treatment of Tarlov Cyst may involve surgery, when these cysts present pain and pelvic dysfunction. In most cases, the prognosis is good, since it is a benign tumor. In case of surgery, the prognosis depends on several factors; in many individuals, neurological complications following treatment is usually noted

According to classification of meningeal cysts, Tarlov Cysts are classified as type II spinal meningeal cysts, since they are extradural and contain neural tissue (or nervous tissue). Extradural means “outside the dura mater, but within the spine”.

Who gets Tarlov Cyst? (Age and Sex Distribution)

• Tarlov Cysts are common lesions that may be found in between 5-9% of the human population 
• 80% of these lesions are diagnosed in adults in the 30-60 years’ age range
• Symptomatic cysts are found among all age groups - in both children and adults
• Both males and females are affected; although these cysts are more frequently diagnosed in women than men. A 13:2 female to male ratio was observed in one large study
• No specific racial or ethnic group predilection is noted

What are the Risk Factors for Tarlov Cyst? (Predisposing Factors)

The following risk factors (mostly connective tissue disorders) have been identified for Tarlov Cyst:

• Ehlers-Danlos syndrome (EDS)
• Loeys-Dietz syndrome
• Marfan syndrome
• Sjögren syndrome

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Tarlov Cyst? (Etiology)

The cause of development of a Tarlov Cyst is generally unknown.

• These cysts are believed to form due to inflammation of the spinal nerve root sheaths, which may be due to an abnormal development or injury of the nerve root sheath, resulting in the formation of cerebrospinal fluid filled sacs
• It is researched that children with connective tissue (genetic) disorders, such as Marfan syndrome or Sjögren syndrome, are at a higher risk for Tarlov Cyst formation

What are the Signs and Symptoms of Tarlov Cyst?

The signs and symptoms of Tarlov Cyst can vary from one individual to another and depends on the size and location of the cystic tumor. In general, small tumors may be asymptomatic and no significant symptoms observed, while large tumors are known to present symptoms. The onset of symptoms and speed of progression of the tumor can vary. In many individuals, tumors that grow slowly and remain asymptomatic, are only diagnosed during certain radiological imaging studies of the region, which are performed for unrelated health conditions.

A minority of Tarlov Cysts are asymptomatic, meaning they present no symptoms (observed in about 3% of the cases). Some cysts can compress on the surrounding nerves resulting in a set of signs and symptoms that depend on the nerve that is affected. Pain in the region of the cysts, which is progressive and chronic, is typically the first observation. These cystic tumors may form anywhere in the spinal cord. Most commonly, they are diagnosed in the lower most part of the spine, particularly the lumbar and sacral region. Also, an injury to the region, may cause a previously asymptomatic (and undiagnosed) cyst to potentially flare up.

The signs and symptoms of Tarlov Cyst may include any of the following:

• Presence of visible lump in the affected region
• Lower back pain that is present for a prolonged period; the pain may be mild initially and become severe over time. The pain may spread to the buttocks
• Unable to bend, walk, or sit
• Numbness and tingling sensation
• Nerve root compression (radiculopathy)
• Compression injury to the spinal cord due to mass effect of the tumor (myelopathy)
• Weakness and pain in the arms and legs, depending on the nerves that are compressed by the tumor; loss of strength in the arms of legs
• Body muscle weakness
• Loss of reflexes
• Partial or full loss of control over bowel and bladder function
• Sexual dysfunction; difficulty having sex
• Gait disturbances, walking difficulties
• Balance and coordination issues
• Loss of sensations that may include sight, hearing, smell and/or taste
• Personality changes
• Partial paralysis
• Other forms of neurological deficits

Large-sized cystic tumors cause significant signs and symptoms. Most of the tumors are single; but occasionally, multiple tumors can be detected growing simultaneously in the spinal cord region, particularly in individuals with genetic disorders. The associated symptoms of the underlying condition, if any present, may be noted.

How is Tarlov Cyst Diagnosed?

A majority of Tarlov Cysts may remain undiagnosed for prolonged periods, because they are asymptomatic and generally slow-growing. The slow development of symptoms and (currently) limited information/literature availability on Tarlov Cysts may further contribute to a delayed detection and diagnosis of these cysts. Mostly these are detected incidentally, when there is a sudden worsening of symptoms prompting the healthcare provider to perform radiological studies of the spinal cord region. Tumors closer to the pelvic region may be discovered following visits to the physician for bladder, bowel, or sexual dysfunction issues.

There are a variety of tests the healthcare provider may employ to diagnose Tarlov Cyst, which may include:

• Physical examination and complete medical history screening
• Assessment of the presenting signs and symptoms
• Neurological, motor skills, and cognitive assessment:
  • Checking intellectual ability, memory, mental health and function, language skills, judgment and reasoning, coordination and balance, reflexes, and sensory perceptions (space, sight, hearing, touch, etc.)
  • The healthcare provider/neurologist may use the Karnofsky Performance Scale in order to assess the neurological functioning of the individual’s central nervous system (CNS)
• Electroencephalography (EEG)
• Electromyography with nerve conductivity tests
• Imaging studies that may be performed include:
  • X-ray of the vertebral column
  • Ultrasound studies of the abdomen and pelvic region
  • Computerized tomography (CT) scan of the vertebral column; CT with contrast
  • Magnetic resonance imaging (MRI) scan of the central nervous system; MRI with contrast agents such as gadolinium
  • Cerebral angiographic studies or MR angiography: An angiogram involves injecting dye into the bloodstream, which makes the blood vessels to appear visually on X-rays. The X-ray may show a tumor in the blood vessels leading into the tumor
  • Magnetic resonance spectroscopy: This radiological technique is used to study the chemical profile of the tumor. It is often performed with and compared to corresponding MRI scan images of the affected region
• Urological studies such as cystoscopy, ureteroscopy, and intravenous pyelogram, based on the presenting symptoms
• Cerebrospinal fluid analysis, where a spinal tap or lumbar puncture procedure may be performed: This diagnostic test is used to remove a sample of cerebrospinal fluid (CSF) from the spaces in and around the spinal cord. The sample is removed from the lower spinal cord using a thin needle, and it is then checked for the presence of cancer cells
• Molecular studies, if necessary

Tissue biopsy: A biopsy of the affected region (spinal cord) is performed and sent to a laboratory for a pathological examination. A pathologist examines the biopsy sample under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis. Examination of the biopsy sample under a microscope by a pathologist is considered to be gold standard in arriving at a conclusive diagnosis.

A differential diagnosis to eliminate other conditions or tumor types may be considered, before arriving at a definitive diagnosis.

The radiological definitive diagnosis includes:

• Dural ectasia
• Meningocele
• Nerve sheath tumor
• Spinal synovial cyst
• Metastasis to the spinal cord region

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Tarlov Cyst?

The complications of Tarlov Cyst may include the following:

• Stress and anxiety due to fear of the tumor
• Large tumor masses may get secondarily infected with bacteria or fungus
• Tumor rupture and torsion: Usually, larger tumors are more prone for torsion
• Large tumors may also press against the vertebral bones causing it to expand or break easily when subjected to minor trauma including falls and accidents
• Large undetected tumors can severely affect spinal cord and be disabling or even life-threatening, due to mass effect/compression of surrounding tissue
• Some cysts are known to erode the surrounding sacral or lumbar bone; this may result in a herniated disc, or even in degenerative disc disease
• Some painful and symptomatic cysts may severely affect the overall quality of life
• Complications due to an underlying genetic disorder, if any present
• Recurrence of the cyst following treatment or its incomplete surgical removal; collapsed and drained cysts are known to almost immediately fill up with cerebrospinal fluid
• Damage to the muscles, vital nerves, and blood vessels, during surgery; the risk for nerve damage remains high during invasive procedures
• Removing or treating the tumor is known to worsen the signs and symptoms in some individuals
• Post-surgical infection at the wound site is a potential complication

How is Tarlov Cyst Treated?

In many cases, no treatment may be necessary for asymptomatic Tarlov Cysts. There are currently no specific treatment protocols to address the condition.

A treatment for symptomatic cysts may involve the following measures:

• In some cases of small tumors and considering their slow-growing rates, the healthcare provider may consider conservative ‘wait and watch’ measures, instead of immediately recommending surgery to remove them
• Symptom treatment may involve the following:
  • Administration of non-steroidal anti-inflammatory drugs (NSAIDs) to treat inflammation
  • Nerve pain relief through transcutaneous electrical nerve stimulation (TENS)
• Non-surgical measures may be initially considered, which may include:
  • Drainage of fluid from the cyst via fine needle aspiration (FNA) under CT guidance
  • Sealing the cyst using a fibrin sealant following aspiration

Generally, the treatment of choice is a complete surgical excision, since this reduces the risk of cyst recurrence. This is mostly considered for cysts greater than 1.5 cm in size that present severe pain and/or dysfunction of the pelvic structures.

• Surgical measures that may be considered include:
  • Making an open incision, draining the CSF, and then injecting a fibrin glue into the cyst space (or, using muscle tissue to fill the void)
  • In case of nerve pain, a nerve root excision or decompressive laminectomy may be undertaken
• Undertaking suitable treatment for the underlying genetic condition, if present

Follow-up care with regular screening and check-ups are important and encouraged.

How can Tarlov Cyst be Prevented?

Currently, there are no known methods to prevent the development of Tarlov Cyst. In case of an associated genetic condition (connective tissue disorder), the following may be considered:

• Genetic testing of the expecting parents (and related family members) and prenatal diagnosis (molecular testing of the fetus during pregnancy) may help in understanding the risks better during pregnancy
• If there is a family history of the condition, then genetic counseling will help assess risks, before planning for a child

What is the Prognosis of Tarlov Cyst? (Outcome/Resolutions)

The prognosis is usually good for small and asymptomatic Tarlov Cysts, since these are benign cysts.

• The prognosis of symptomatic Tarlov Cysts with treatment (surgery) depend on the success of the invasive procedures
• Post-operative complications may result in irreversible nerve injury or cerebrospinal fluid leakage, which increases the risk for infections and bacterial meningitis
• In some individuals, pain management sessions may be necessary to improve the quality of one’s life

Additional and Relevant Useful Information for Tarlov Cyst:

The following article link will help you understand other cancers and benign tumors:

http://www.dovemed.com/diseases-conditions/cancer/