Tarlov Cyst – Comprehensive Medical Guide

Overview

Tarlov cysts, also called perineural (nerve‑root) cysts, are fluid‑filled sacs that develop at the junction of a spinal nerve root and the surrounding dura mater. The cysts contain cerebrospinal fluid (CSF) and are most commonly found in the sacral region of the spine (S2‑S4), though they can appear anywhere along the spinal canal.

These cysts are usually discovered incidentally on magnetic resonance imaging (MRI) performed for another reason, and most people never experience symptoms. When symptoms do occur, they can mimic other nerve‑compression disorders, making diagnosis challenging.

• Who it affects: Adults 30–60 years old, with a slight female predominance (≈ 55 %).
• Prevalence: Autopsy and imaging studies suggest that up to 4.5 % of the general population have at least one Tarlov cyst, but only 0.1–1 % become clinically significant.¹
• Geographic variation: No clear regional differences have been documented; cysts are reported worldwide.

Symptoms

Because most cysts are asymptomatic, the presence of a Tarlov cyst alone does not confirm disease. When symptoms arise, they are typically related to pressure on adjacent nerve roots, blood vessels, or bony structures. The following list includes the most commonly reported manifestations, each with a brief description.

Pain

• Low back or sacral pain: Deep, aching discomfort that may worsen with prolonged standing or sitting.
• Radicular pain: Sharp, shooting pain radiating from the sacrum into the buttocks, hips, thighs, or down the legs (sciatica‑like pattern).
• Post‑exertional worsening: Pain that intensifies after physical activity, especially activities that increase intra‑abdominal pressure (e.g., coughing, lifting).

Sensory disturbances

• Tingling, “pins‑and‑needles,” or numbness in the perineal area, buttocks, inner thighs, or genital region.
• Altered sensation during sexual activity, occasionally described as “reduced pleasure” or “painful orgasm.”

Motor changes

• Weakness in the muscles of the pelvic floor, leading to difficulty with urinary or bowel control.
• Occasional foot drop if the cyst compresses nerve roots higher up the sacral spine.

Autonomic symptoms

• Urinary urgency, frequency, or retention.
• Fecal incontinence or constipation.
• Sexual dysfunction, including erectile dysfunction in men and dyspareunia in women.

Other reported symptoms

• Headaches that worsen when lying flat (due to CSF dynamics).
• Chronic fatigue, possibly related to ongoing nerve irritation.
• Radicular pain that is aggravated by Valsalva maneuvers (coughing, sneezing).

Because many of these symptoms overlap with herniated discs, pelvic floor disorders, and other spinal pathologies, a thorough clinical evaluation is essential.

Causes and Risk Factors

The exact origin of Tarlov cysts remains uncertain, but several theories and risk factors have been identified.

Proposed mechanisms

• Congenital weakness: A developmental defect in the perineurium that predisposes the nerve root sheath to balloon out with CSF.
• Trauma: Minor spinal injuries or repeated micro‑trauma may cause a breach in the dura, allowing CSF to accumulate.
• Elevated CSF pressure: Conditions that raise intracranial or intraspinal pressure (e.g., obesity, chronic coughing) may promote cyst expansion.
• Inflammation: Inflammatory processes, such as meningitis, could weaken the dura and initiate cyst formation.

Risk factors

• Age: Incidence rises after the third decade of life.
• Gender: Slightly higher prevalence in females.
• Spinal abnormalities: Prior disc herniation, spinal stenosis, or scoliosis increase the likelihood of cyst development.
• Connective‑tissue disorders: Conditions like Ehlers‑Danlos syndrome have been linked to higher rates of perineural cysts.
• Obesity: Higher body mass index may augment CSF pressure, encouraging cyst growth.
• History of trauma: Sports injuries, falls, or motor‑vehicle accidents.

Diagnosis

Diagnosing a symptomatic Tarlov cyst involves correlating imaging findings with the patient’s clinical picture. No single test confirms that the cyst is the source of symptoms; rather, a combination of studies helps build a convincing case.

Imaging studies

• Magnetic Resonance Imaging (MRI): The gold‑standard modality. Tarlov cysts appear as well‑defined, CSF‑signal (bright on T2‑weighted images) lesions attached to a nerve root. MRI can show cyst size, location, and any adjacent neural compression.²
• Computed Tomography (CT) myelography: Useful when MRI is contraindicated. Injection of contrast into the CSF outlines the cyst and demonstrates any communication with the subarachnoid space.
• Standing or dynamic MRI: Occasionally used to assess changes in cyst size with posture, especially for patients whose pain worsens when upright.

Electrodiagnostic testing

• Electromyography (EMG) & Nerve Conduction Studies (NCS): May reveal abnormalities in the nerve roots supplied by the affected segment, supporting the cyst’s symptomatic role.

Other assessments

• Physical examination: Sensory deficits, motor weakness, and special tests (e.g., straight‑leg raise, sacral reflexes) help localize the problem.
• Urodynamic studies: If urinary dysfunction is prominent, these tests evaluate bladder function and rule out primary urological causes.

Because many individuals have incidental cysts, a practitioner will often look for a clear correlation between the cyst’s size/location and the patient’s symptoms before recommending invasive treatment.

Treatment Options

Management is individualized, ranging from conservative measures for mild cases to minimally invasive or surgical interventions for refractory symptoms.

Conservative (first‑line) therapy

• Activity modification: Limiting activities that increase intra‑abdominal pressure (heavy lifting, prolonged sitting) can reduce pain.
• Physical therapy: Core‑strengthening, pelvic‑floor rehabilitation, and gentle stretching may alleviate nerve irritation.
• Pain management:
  • Acetaminophen or non‑steroidal anti‑inflammatory drugs (NSAIDs) for mild‑to‑moderate pain.
  • Gabapentin or pregabalin for neuropathic pain, following guidance from a neurologist or pain specialist.
  • Short courses of oral steroids (e.g., prednisone) may reduce inflammation around the cyst.
• Lifestyle measures: Weight loss, smoking cessation, and regular low‑impact aerobic exercise improve overall spinal health.
• Epidural or perineural steroid injections: Fluoroscopically guided injections can provide temporary relief by decreasing local inflammation.

Minimally invasive procedures

• Cyst aspiration + fibrin glue: Under CT or fluoroscopic guidance, the cyst is emptied and then sealed with fibrin glue to prevent re‑accumulation. Success rates of pain relief range from 50–70 % in selected series.³
• Endoscopic fenestration: Small endoscopic tools create a permanent opening between the cyst and the CSF space, allowing drainage.

Surgical options

Surgery is considered when conservative measures fail after 3–6 months and the cyst is clearly linked to disabling symptoms.

• Laminectomy with cyst excision: Removal of the cyst and part of the lamina to decompress the nerve root. Reported symptom improvement in 70–80 % of cases, but carries risks of spinal instability and CSF leak.⁴
• Microsurgical cyst wall resection with duraplasty: Precise removal of the cyst wall combined with reinforcement of the dura to prevent recurrence.
• Shunt placement: A small tube diverts CSF from the cyst to the peritoneal cavity; rarely used due to infection risk.

When to consider surgery

• Progressive neurological deficits (e.g., worsening weakness or bowel/bladder loss).
• Persistent, severe pain unresponsive to ≥ 3 months of optimized conservative therapy.
• Evidence of cyst enlargement on serial imaging correlated with symptom escalation.

Living with Tarlov Cyst

Even after a definitive treatment plan, day‑to‑day management is crucial for quality of life.

Self‑care strategies

• Maintain a healthy weight: Reducing abdominal pressure can limit cyst expansion.
• Ergonomic posture: Use chairs with lumbar support; avoid prolonged sitting without breaks.
• Regular low‑impact exercise: Swimming, stationary cycling, or yoga improve core stability without stressing the sacrum.
• Pelvic floor therapy: Targeted exercises can address urinary or sexual dysfunction.
• Heat/Cold therapy: Applying a warm pack can relax tense muscles; an ice pack may reduce acute flare‑ups.

Monitoring and follow‑up

• Schedule MRI reassessment every 12–24 months if the cyst is large (> 2 cm) or previously symptomatic.
• Keep a symptom diary (pain intensity, triggers, urinary changes) to discuss with your provider.
• Contact your physician promptly if you notice new weakness, numbness, or changes in bladder/bowel function.

Psychosocial support

Chronic pain can affect mood and daily functioning. Consider counseling, support groups, or cognitive‑behavioral therapy (CBT) to cope with anxiety or depression related to the condition.

Prevention

Because many Tarlov cysts arise from congenital factors, true primary prevention is limited. However, you can reduce the chance of cyst growth or symptom onset by adopting spinal‑protective habits.

• Maintain a healthy body mass index (BMI < 25 kg/m²).
• Avoid chronic Valsalva‑type activities (e.g., heavy weightlifting, chronic coughing without treatment).
• Promptly treat respiratory infections or allergies that cause persistent coughing.
• Use proper lifting techniques—bend at the hips and knees, keep the load close to the body.
• Engage in regular core‑strengthening exercises to support the lumbar and sacral spine.

Complications

If a symptomatic cyst is left untreated, the following complications may develop:

• Progressive neurological deficit: Ongoing compression can lead to irreversible motor weakness or sensory loss.
• Chronic urinary or bowel dysfunction: Persistent sphincter impairment may require catheterization or surgical intervention.
• Sexual dysfunction: Chronic pain and nerve involvement may cause lasting erectile or orgasmic difficulties.
• CSF leak: Large cysts that rupture can cause low‑pressure headaches, nausea, and occasional meningitis.
• Spinal instability: Rarely, large cysts erode bone, increasing the risk of vertebral fracture.
• Psychological impact: Chronic pain and disability can lead to depression, anxiety, and reduced employment capacity.

When to Seek Emergency Care

References

1. Saifuddin T, et al. “Perineural (Tarlov) cysts: a systematic review.” *Neurosurgery* 2016.
2. Cleveland Clinic – Tarlov Cysts.
3. Kumar A, et al. “Tarlov Cyst Management: A Review of the Evidence.” *Journal of Family Medicine* 2019.
4. Mayo Clinic – Tarlov Cyst Diagnosis & Treatment.
5. Centers for Disease Control and Prevention (CDC)
6. World Health Organization (WHO)