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Elfaal and Samir: Tarlov cyst – an uncommon cause of back pain


Small asymptomatic cysts occur in 5–9% of the general population in the USA.1 However, large cysts that cause symptoms are relatively rare (symptomatic cases constituting less than 1% of the total) and are more common in women aged 31–60 years.1,2


The exact cause is unknown; Tarlov posited that haemorrhage into the subarachnoid space caused accumulations of red blood cells that impeded the drainage of the veins in the perineurium and epineurium, leading to rupture with subsequent cyst formation.3 Four out of the seven patients in Tarlov’s 1970 study had a history of trauma.4

Many theories exist, including that the cyst is formed as a result of inflammation, or nerve root injury from trauma, causing the cerebrospinal fluid (CSF) to leak into the space where the cyst is formed; other researchers believe that it is a result of a congenital connection between the subarachnoid space and the perineural region of the affected nerves.5

Some authors believe that some events and conditions might potentially cause the asymptomatic cyst to become symptomatic, such as traumatic injuries resulting from falls or motor accidents, lifting heavy objects, childbirth or epidurals.6

Clinical presentation

Symptomatic cysts mainly cause sensory symptoms because of the proximity of the cysts to the dorsal root and ganglion. If the cyst is large enough to compress the ventral root, motor deficits occur. Large cysts can affect multiple nerves. Common presentations are lower back pain, perineal pain, sciatica, sexual dysfunction, neurogenic claudication, leg numbness, leg weakness and bowel or urinary bladder difficulties.711

The pain can be sharp and sudden or milder and achy, is commonly intermittent, and increased by standing, walking and coughing. Bed rest decreases the pain, and pressure over the sacrum may cause tenderness.4

Radiological features

  • Radiographs are usually normal, but might reveal bone erosions of the spinal canal and neural foramina.12

  • Computerized tomography (CT) may demonstrate the erosions and show the cyst as a CSF-isodense mass at the foramina.13

  • Magnetic resonance imaging (MRI) is the investigation of choice, with the best soft tissue contrast; the cyst will be identified by a CSF signal, with low signal intensity in T1-weighted images and high signal intensity in T2-weighted images (Figure 1), as well as its shape and the vicinity of its location to the dorsal ganglion (Figure 2).17,18

  • On myelography, filling of the meningocele sac 1 hour after the injection of contrast medium is highly suggestive of a Tarlov cyst.19


A well-defined 3.3 × 1.7 cm cystic lesion at S2/S3 level. The lesion has CSF signal in all pulse sequences, in keeping with symptomatic Tarlov cysts.14 (a) Sagittal magnetic resonance myelogram, T2; (b) sagittal magnetic resonance myelogram showing the CSF-like cyst;14 and (c) sagittal T1 magnetic resonance image of the lumbar spine demonstrating a right posterolateral annular fissure of the L4/5 disc.15 Images reproduced under the Creative Commons Non-Commercial License (


(a) Coronal short tau inversion recovery image and (b) axial T2 image showing incidentally found asymptomatic bilateral Tarlov cysts. Images reproduced under the Creative Commons Non-Commercial License (


Histopathological features

Histopathological examination reveals inflamed layers of meninges and the presence of neural elements (Figure 3).20


(a) Cyst wall lined by flattened to cuboidal epithelium. The subepithelial tissue shows a nerve bundle and fibrocollagenous tissue with congested blood vessels [haematoxylin and eosin stain (H&E), ×50]. (b) Cyst wall lined by flattened to cuboidal epithelium, which is thrown into papillae in one focus. The subepithelial tissue shows a nerve bundle and fibrocollagenous tissue with congested blood vessels (H&E, ×50). (c) Cyst wall lined by flattened to cuboidal epithelium, which is thrown into papillae in one focus. The subepithelial tissue shows a nerve bundle and fibrocollagenous tissue with congested blood vessels (H&E, ×50). (d) Cyst wall lined by low columnar epithelium with cells that have round to oval elongated nuclei. The subepithelial tissue shows a nerve bundle (H&E, ×50). Images reproduced under the Creative Commons Non-Commercial License (



Despite advancements in diagnosis, there is controversy regarding the best treatment of symptomatic Tarlov cysts.21 Treatment options are:

  1. lumbar drainage or CT-guided percutaneous aspiration of the cyst with or without infusion of fibrin glue;

  2. peritoneal or subarachnoid shunt;

  3. decompression by laminectomy;

  4. partial cyst removal with cyst wall imbrication, or removal with neck ligation (with or without nerve root resection);

  5. microsurgical cyst removal and cyst wall imbrication together with defect repair with muscle, Gelfoam (Pharmacia and Upjohn Company, Kalamazoo, MI, USA) or fibrin glue;

  6. microsurgical fenestration of sacral perineural cysts to the thecal sac.2,2125


The majority of Tarlov cysts, being asymptomatic, are never diagnosed. However, when a doctor suspects Tarlov cyst in cases of unexplained lower back pain, MRI is the investigation of choice. The treating physician should order a full sacral spine MRI, all the way to the coccyx, as 95% of cysts are found in the sacral spine.



American Association of Neurological Surgeons. Tarlov Cyst. 2006. URL: (accessed 27 June 2016).


Paulsen RD, Call GA, Murtagh FR. Prevalence and percutaneous drainage of cysts of the sacral nerve root sheath (Tarlov cysts). Am J Neuroradiol 1994; 15:293–9.


Sharma M, Velho V, Mally R, Khan SW. Symptomatic lumbosacral perineural cysts: a report of three cases and review of literature. Asian J Neurosurg 2015; 10:222–5.


Tarlov IM. Spinal perineurial and meningeal cysts. J Neural Neurosurg Psychiatry 1970; 33:833–43.


National Organization for Rare Diseases. Tarlov Cysts. URL: (accessed 27 June 2016).


Tarlov Cyst Disease Foundation. Tarlov Cyst Information. URL: (accessed 27 June 2016).


Ellis ME. Perineural Cysts. 2016. URL: (accessed 27 June 2016).


Tarlov IM. Cysts of the sacral nerve roots; clinical significance and pathogenesis. AMA Arch Neurol Psychiatry 1952; 68:94–108.


ArunKumar MJ, Selvapandian S, Chandy MJ. Sacral nerve root cysts: a review on pathophysiology. Neurol India 1999; 47:61–4.


Jain SK, Chopra S, Bagaria H, Mathur PP. Sacral perineural cyst presenting as chronic perineal pain: a case report. Neurol India 2002; 50:514–15.


Nadler SF, Bartoli LM, Stitik TP, Chen B. Tarlov cyst as a rare cause of S1 radiculopathy: a case report. Arch Phys Med Rehabil 2001; 82:689–90.


Taveras JM, Wood EH. Diagnostic Neuroradiology. Baltimore, MD: Williams & Wilkins; 1976. pp. 1139–45.


Tabas JH, Deeb ZL. Diagnosis of sacral perineural cysts by computed tomography. J Comput Tomogr 1986; 10:255–9.


Balachandran G. Tarlov Cyst. Radiopaedia. URL: (accessed 27 June 2016).


Gaillard F. Annular Fissure. Radiopaedia. URL: (accessed 27 March 2017).


Gaillard F. Tarlov Cysts – MRI. Radiopaedia. URL: (accessed 27 March 2017).


Rodziewicz GS, Kaufman B, Spetzler RF. Diagnosis of sacral perineural cysts by nuclear magnetic resonance. Surg Neurol 1984; 22:50–2.


Kim K, Chun SW, Chung SG. A case of symptomatic cervical perineural (Tarlov) cyst: clinical manifestation and management. Skeletal Radiol 2012; 41:97–101.


Nishiura I, Koyama T, Handa J. Intrasacral perineurial cyst. Surg Neurol 1985; 23:265–9.


Joshi VP, Zanwar A, Karande A, Agrawal A. Cervical perineural cyst masquerading as a cervical spinal tumor. Asian Spine J 2014; 8:202–5.


Guo D, Shu K, Chen R, Ke C, Zhu Y, Lei T. Microsurgical treatment of symptomatic sacral perineurial cysts. Neurosurgery 2007; 60:1056–65.


Bartels RH, van Overbeeke JJ. Lumbar cerebrospinal fluid drainage for symptomatic sacral nerve root cysts: an adjuvant diagnostic procedure and/or alternative treatment? Technical case report. Neurosurgery 1997; 40:861–5.


Caspar W, Papavero L, Nabhan A, Loew C, Ahlhelm F. Microsurgical excision of symptomatic sacral perineurial cysts: a study of 15 cases. Surg Neurol 2003; 59:101–6.


Voyadzis JM, Bhargava P, Henderson F. Tarlov cysts: a study of 10 cases with review of the literature. J Neurosurg 2001; 95:25–32.


Neulen A, Kantelhardt SR, Pilgram-Pastor SM, Metz I, Rohde V, Giese A. Microsurgical fenestration of perineural cysts to the thecal sac at the level of the distal dural sleeve. Acta Neurochir 2011; 153:1427–34.

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