Tarlov Cyst: Symptoms, Types, Causes and Treatment

Tarlov cysts, also known as perineural cysts, are fluid-filled sacs that form most commonly around the nerve roots in the lower spine. Although often discovered incidentally during imaging for unrelated problems, Tarlov cysts can sometimes cause significant neurological symptoms and pain. Understanding the symptoms, types, causes, and treatment options is essential for those affected and for clinicians managing these often misunderstood lesions.

Symptoms of Tarlov Cyst

Tarlov cysts are often silent passengers, going unnoticed for years until they reach a size or location that disrupts nerve function. However, when symptoms do occur, they can affect daily life in profound ways, from causing chronic pain to interfering with bladder and bowel control. Recognizing the patterns and range of symptoms is crucial for timely diagnosis and effective management.

Symptom	Description	Frequency/Notes	Source
Back Pain	Chronic or intermittent lower back pain	Most common presenting symptom	2 3 5
Radiculopathy	Nerve root pain radiating to legs/pelvis	Can mimic sciatica	2 3 5
Bladder Issues	Urinary incontinence or dysfunction	Sphincter disturbance in some cases	1 2 3 5 7
Sexual Dysfunction	Dyspareunia, genital numbness, PGAD	Sometimes underrecognized	2 3 5
Bowel Disturbance	Constipation or incontinence	Less common but possible	3 5
Sensory Changes	Numbness, tingling, or burning sensation	May be diffuse or localized	3 5

Table 1: Key Symptoms

Overview of Common Symptoms

Tarlov cysts most often cause lower back pain or sacral pain, often described as deep, aching, or burning. This pain can radiate (radiculopathy) to the buttocks, legs, perineum, or pelvic area, depending on which nerve roots are compressed or irritated 2 3 5.

Neurological and Pelvic Symptoms

• Bladder and Bowel Dysfunction: Some patients experience urinary incontinence or trouble holding their urine; others may have difficulty emptying the bladder or bowel 1 2 3 5 7. These symptoms often point to larger cysts or those pressing directly on sacral nerve roots.
• Sexual Dysfunction: Dyspareunia (painful intercourse), reduced genital sensation, and even persistent genital arousal disorder (PGAD) have been linked to Tarlov cysts 2 3 5. These symptoms are often overlooked but can be distressing and affect quality of life.
• Sensory and Motor Changes: Numbness, tingling, burning, or even weakness in the legs and pelvic region can develop as cysts grow or when they are aggravated by trauma or increased cerebrospinal fluid (CSF) pressure 3 5.

Factors Affecting Symptom Severity

• Cyst Size and Location: Larger cysts (>1.5 cm) and those impinging directly on nerve roots are more likely to cause severe symptoms, including radicular pain and pelvic organ dysfunction 1.
• Physical Activity: Symptoms often worsen with sitting, standing, walking, or activities that increase CSF pressure, such as coughing 3.
• Incidental Findings: Not all Tarlov cysts cause symptoms—many are found unintentionally during imaging for other reasons 5 6.

Types of Tarlov Cyst

Tarlov cysts are not a one-size-fits-all diagnosis. They can vary in number, size, and anatomical details, which influences both symptoms and management strategies. Understanding the main types helps clarify both prognosis and treatment options.

Type	Location/Description	Clinical Relevance	Source
Isolated	Single cyst, usually in sacral region	May be asymptomatic or symptomatic	2 3 5
Multiple	Several cysts along nerve roots	May cause more complex symptoms	2 5 6
Large (>1.5cm)	Bigger cysts (diameter >1.5 cm)	Higher risk of neurological symptoms	1 8
Small (<1.5cm)	Smaller cysts	Often asymptomatic	1 8

Table 2: Tarlov Cyst Types

Anatomical Classification

Most Tarlov cysts are found in the sacral region of the spine, particularly around the S2–S3 nerve roots, but they can appear anywhere along the lumbosacral nerve roots 1 2 3 5.

• Isolated vs. Multiple Cysts: Some individuals have a single cyst, while others may have multiple cysts affecting several nerve roots. Multiple cysts can complicate symptoms and treatment 2 5 6.
• Size Matters: Cysts are broadly classified by size—those larger than 1.5 cm are more likely to cause symptoms due to greater nerve compression 1 8. However, even smaller cysts can cause symptoms depending on their precise location.

Pathological Subtypes

• Perineural Cysts: These are the classic Tarlov cysts, forming between the perineurium and endoneurium of the nerve root. They contain CSF and may communicate with the subarachnoid space 1 3 5.
• Ganglion-Associated: Some cysts include ganglion cells within their wall, which may influence their behavior and symptomatology 1.

Clinical Implications

• Symptomatic vs. Asymptomatic: The majority of Tarlov cysts are asymptomatic and discovered incidentally. Only a minority become symptomatic and require intervention 5 6 8.
• Imaging and Diagnosis: MRI is the gold standard for detecting Tarlov cysts, assessing their size, number, and relationship to nerve roots 2 3 5.

Causes of Tarlov Cyst

Despite being recognized for decades, the exact causes of Tarlov cysts remain a subject of ongoing research and debate. Several theories have emerged, and understanding these can help patients appreciate why cysts develop—and why some become symptomatic.

Cause	Description	Supporting Evidence	Source
Congenital	Developmental weakness in nerve sheath	Cysts found in early life/families	2 3
Trauma	Injury leading to cyst formation	History of trauma in some cases	1 3
Hydrostatic Pressure	CSF pressure causes cyst expansion	Ball-valve mechanism observed	1 3 5
Inflammation	Chronic inflammation of nerve roots	Some cases linked to inflammation	3
Degenerative	Age-related changes in nerve tissue	Seen in older patients	3 6
Genetic	Possible familial predisposition	Family history in some reports	2 3

Table 3: Causes of Tarlov Cyst

Congenital and Developmental Theories

Some researchers suggest that Tarlov cysts are congenital—resulting from a developmental weakness in the nerve root sheath, which allows cerebrospinal fluid (CSF) to accumulate and form a cyst 2 3. This could explain cases where cysts appear in young patients or run in families.

Trauma and Hydrostatic Pressure

• Trauma: A history of spinal trauma, such as a fall or motor vehicle accident, has been linked to the development of Tarlov cysts in some patients 1 3. Trauma may cause tearing or weakness in the nerve root covering, setting the stage for cyst formation.
• Hydrostatic (CSF) Pressure: The "ball-valve" mechanism is a widely accepted explanation—CSF enters the cyst through a small opening but cannot exit easily, causing the cyst to expand and compress nerves 1 3 5. Activities that increase CSF pressure can therefore aggravate symptoms.

Inflammation and Degenerative Changes

Chronic inflammation or degenerative changes in the nerve root coverings may also predispose to cyst formation, especially in older adults 3 6.

Genetic and Familial Factors

Although less common, some studies have reported familial clustering of Tarlov cysts, suggesting a possible genetic predisposition 2 3. More research is needed to fully understand this risk.

Treatment of Tarlov Cyst

The management of Tarlov cysts is highly individualized. For many, reassurance and observation are all that is needed. For those significantly affected, a range of nonsurgical and surgical options exists, each with its own pros and cons. Choosing the right approach depends on symptoms, cyst characteristics, and patient preferences.

Treatment	Description	Effectiveness/Notes	Source
Observation	Monitoring with no intervention	For asymptomatic/minimally symptomatic cases	1 5 6
Conservative	Pain meds, NSAIDs, physical therapy	First-line for mild-moderate symptoms	3 5
Aspiration/Fibrin Sealant	CT-guided aspiration and fibrin injection	High satisfaction; minimally invasive	4 5
Surgical Resection	Removal of cyst via laminectomy/microsurgery	Can provide symptom relief; risk of recurrence	1 6 7 8
Cyst Clipping	Remodeling cyst wall with clips	Safe, rapid, effective for bladder symptoms	7
Shunting	Diverting CSF away from cyst	Less commonly performed	5

Table 4: Treatment Options

Observation and Conservative Management

For most patients—especially those with small, asymptomatic cysts—no treatment is necessary. Regular monitoring with MRI and clinical follow-up is usually sufficient 1 5 6.

• Conservative Therapy: When symptoms are mild, pain medications (NSAIDs, steroids), neuropathic pain agents, and physical therapy are recommended as first steps 3 5. These strategies aim to manage pain and improve function without invasive procedures.

Minimally Invasive Interventions

• CT-Guided Aspiration and Fibrin Sealant Injection: This outpatient procedure involves aspirating fluid from the cyst and injecting a fibrin sealant to prevent re-accumulation. Studies report high rates of symptom relief and patient satisfaction (over 80% initially; ~74% long-term), with low complication risk 4 5. This makes it a preferred option for many with symptomatic cysts who do not want or are not candidates for surgery.

Surgical Options

• Cyst Wall Resection (Laminectomy/Microsurgery): Surgical removal of the cyst via sacral laminectomy or microsurgical techniques can provide substantial or complete symptom relief in many cases (50–80% in studies), especially in those with larger cysts and severe neurological symptoms 1 6 7 8. However, surgery carries risks of recurrence, neurological damage, CSF leaks, and other complications. Long-term results vary, and pain is less likely to fully resolve compared to neurological deficits 5 8.
• Cyst Clipping: Some surgeons remodel the cyst around the nerve root using titanium clips. This technique is reported to be effective, quick, and safe, particularly for intermittent bladder symptoms 7.
• Shunting: Rarely, shunting procedures are used to divert CSF away from the cyst, but this is not a common approach 5.

Choosing the Right Approach

Treatment decisions are best made collaboratively, considering:

• Severity and type of symptoms
• Cyst size and location
• Patient preference and comorbidities
• Risks and benefits of each intervention

Not all patients require surgery, and many find significant relief with less invasive measures 1 4 5 8.

Conclusion

Tarlov cysts are an underrecognized yet potentially impactful cause of neurological and pelvic symptoms. While most are harmless and require no intervention, a subset can significantly affect quality of life. Understanding the variety of symptoms, types, causes, and treatment options allows for informed decisions and personalized care.

Key Points:

• Symptoms range from back pain and radiculopathy to bladder, bowel, and sexual dysfunction, with symptom severity often related to cyst size and location 1 2 3 5.
• Types include isolated or multiple cysts, with larger cysts (>1.5cm) more likely to cause symptoms 1 2 8.
• Causes are multifactorial, involving congenital, traumatic, inflammatory, degenerative, and possibly genetic factors 1 2 3 5.
• Treatment options span from observation and conservative therapy to minimally invasive procedures (aspiration/fibrin sealant) and surgery, with individualized plans based on patient-specific factors 1 4 5 6 7 8.

If you or someone you know is facing a potential diagnosis of Tarlov cyst, consult with a specialist to explore all options and ensure a tailored, evidence-based approach to care.