MICROSURGICAL TREATMENT OF SYMPTOMATIC SACRAL PERINEURIAL CYSTS

Thecaloscopy Reduces the Risk of Recurrent Perineural (Tarlov) Cysts after Microsurgical Resection

Sacral Tarlov cysts (TCs), often asymptomatic, can cause significant pain and severe neurological dysfunction. Conventional treatments are generally associated with high recurrence and complication rates. Specifically, the substantial recurrence rates, which can reach as high as 50%, significantly impact long-term outcomes. Recent evidence increasingly supports the hypothesis that the formation of Tarlov cysts (TCs) may be associated with inflammatory processes within the nerve root sheath, further exacerbated by elevated cerebrospinal fluid (CSF) pressure. This retrospective study explores thecaloscopy, combined with surgical techniques, as a more effective alternative. We observed a total of 78 patients, 48 of whom underwent endoscopic fenestration of the arachnoid sheath in addition to microsurgical resection of the TC. We found that the fenestration of the arachnoid sheath at the level of lumbosacral spinal nerve root entry led to a significantly decreased risk of developing recurrent TCs (5/48 vs. 9/30). Only one of the patients suffered from a persistent new bladder dysfunction after microsurgical resection. This presented technique provides a promising treatment path for the future management of TCs, offering a safe and more effective treatment option compared to previous methods. Additionally, the advantages of the thecaloscopy provide pathophysiological implications regarding the development of perineural cysts.

Efficacy of neuroendoscopic-assisted surgery in the management of symptomatic sacral perineural (Tarlov) cysts: a technical report

Introduction

The Tarlov cysts are pathological enlargements of the cerebrospinal fluid spaces between the endoneurium and perineurium, which can cause intolerable sciatic pain, motor impairment of lower limbs, and bladder/bowel dysfunction. Currently, the treatment results are unsatisfactory due to the low cure rates and extensive surgical trauma. Thus, there is an ongoing exploration of surgical techniques for Tarlov treatment. In the current study, we present a novel neuroendoscopic-assisted technique that combines the fenestration, leakage sealing, and tamponade of the Tarlov cyst.

Methods

Between January 2020 and December 2021, a total of 32 Tarlov patients were enrolled and received neuroendoscopic-assisted surgery. Their pre- and post-surgical Visual Analogue Scale (VAS) scores, major complaints, and MR imaging were recorded for comparison.

Results

27 of 32 patients (84.4%) patients demonstrated immediate pain relief as their VAS scores decreased from 5.6 ± 1.5 to 2.5 ± 1.1 (p < 0.01) on the first day after surgery. At the 3-month follow-up, the patients' average VAS score continued to decrease (1.94 ± 0.8). Meanwhile, saddle paresthesia, urinary incontinence, and constipation were relieved in 6 (50%), 4 (80%), and 5 (41.7%), respectively, according to patients self-report. No surgical-related complication was observed in any of the cases.

Discussion

We conclude that neuroendoscopic-assisted surgery is an effective surgical method for symptomatic Tarlov cysts with minimized complications.

A systematic review of the efficacy of surgical intervention in the management of symptomatic Tarlov cysts: a meta-analysis

Introduction: Tarlov cysts (TC) are sacral perineural cysts that are often found incidentally during spinal imaging. In a small fraction, symptomatic TC can cause pain, bowel, bladder and/or sexual dysfunction, as well as motor and sensory deficits. While many surgeons regard TCs as a non-operative entity, there have been suggestions that operative intervention in carefully selected symptomatic patients may be beneficial. The aim of this meta-analysis is to identify whether surgical treatment for symptomatic TCs is beneficial with an acceptable complication profile.Materials and methods: The authors conducted a systematic outcome analysis of symptomatic TCs treated either with surgery or conservatively managed.Results: Sixteen studies (N = 238) met the inclusion criteria for final meta-analysis. The literature search was performed using PubMed, Ovid MEDLINE, CINAHL, and EMBASE databases up to September 2017 and with an updated search in April 2019. The post-operative complication rate in patients undergoing surgical intervention was 16.9 (11.8 to 22.7) and cyst recurrence was 8.5 (3.5 to 15.4). When a complication occurred, the most frequent complication of surgical intervention was the development of a surgical site infection and/or CSF leak. Of the 15 studies reporting long-term follow-up, 81.0 (74.0-88.0) of patients remained symptom-free for more than 1 year (Mean: 27.5 months, SD = 11.5).Conclusion: We rigorously analyse the efficacy of open surgical decompression and repair of symptomatic TCs and corroborate the findings of sustained long-term resolution of symptoms.

A bibliometric and visualization study of global research trends in sacral Tarlov cyst from 2000 to 2022

Background

Symptomatic sacral Tarlov cyst (STC) exerts a significant negative impact on the patient's quality of life, highlighting the significance of the increasing number of studies on STC. However, bibliometric analyses in this research field are scarce. Thus, this study aims to provide a comprehensive knowledge structure and identify the research trends of STC through bibliometrics.

Methods

Articles related to STC from 2000 to 2022 were sourced from the Web of Science Core Collection database. VOSviewer 1.6.16, CiteSpace 6.1.6, GraphPad Prism 8.2.1 and R-package "bibliometrix" were used to analyse the data and generate knowledge maps.

Results

A total of 930 studies on STC from 2000 to 2022 were included. The findings revealed a consistent yet upward trend in the number of annual publications in this field. The United States, China and Turkey were the most prolific and influential countries contributing to this field, with the University of Illinois, the University of Maryland and the National Institute of Standards & Technology being the most notable research institutions. Key journals include World Neurosurgery [Impact Factor (IF) = 2.210], Journal of Vascular Surgery (IF = 4.860) and Journal of Neurosurgery-Spine (IF = 3.467). Additionally, Tarlov Mj, Tarlov E and Zachariah Mr exhibit the highest number of publications, making them the leading authors in this field. A twenty-year retrospection of research trends using keyword analysis reveals four principal directions, namely "definition", "pathogenesis", "diagnosis" and "treatment". Currently, therapeutic surgical intervention is the key treatment for this disease, with future treatments primarily hinging on minimally invasive methodologies rooted in microendoscopic and endoscopic techniques.

Conclusion

This pioneering, comprehensive scientific bibliometric study provides a holistic summary of STC research trends and hot spots spanning the past 22 years. The results identify existing research frontiers and chart maps for future studies, serving as a valuable reference for scholars vested in this field.

Management of Tarlov cysts: an uncommon but potentially serious spinal column disease-review of the literature and experience with over 1000 referrals

Tarlov cysts were thought to be anatomic variants of uncertain etiology and clinical significance when initially described over 80 years ago. They are often detected in routine lumbosacral imaging and generally not reported in a differential diagnosis. There is increasing evidence that at least some Tarlov cysts are symptomatic and can have a significant adverse impact on patients' health and well-being. Women are disproportionately affected with this condition, often presenting with long-standing pain and neurological dysfunctions. Significant gender bias has been a concern in the management of these patients. Unfortunately, there is no consensus on patient selection or management approaches for symptomatic Tarlov cysts. This review article updates information on the prevalence, diagnosis, clinical significance, and treatments of these cysts. Based on these findings and experience with over 1000 patient referrals, a treatment decision algorithm for symptomatic Tarlov cysts was constructed to provide guidance for appropriate management of patients with these complex cysts.

Operative Treatment of Tarlov Cysts - Outcomes and Predictors of Improvement after Surgery: A Series of 97 Consecutive Patients and a Systematic Review of Literature

STUDY DESIGN

A register-based retrospective series and a systematic review of literature.

OBJECTIVES

Tarlov cysts are meningeal cysts typically found in the sacral region. They have a dualistic nature ranging from an incidental finding to a symptomatic pathology. There are no established treatment protocols and predictors of operative outcome. Therefore, we aimed to study the outcome of surgical treatment for Tarlov cysts and to characterize patient-, and treatment-related factors predicting outcomes.

METHODS

A systematic review of previous literature was performed and a retrospective cohort of all patients operated on for Tarlov cysts at BLINDED between 1995 and 2020 was collected. Patient records were evaluated along with radiological images.

RESULTS

Ninety-seven consecutive patients were identified with follow-up data available for 96. Improvement of symptoms after surgery was observed in 76.0% of patients (excellent or good patient-reported outcome) and the complication rate was 17.5%. Sacral or lower back pain as a preoperative symptom was associated with improvement after surgery (P = .007), whereas previous lower back surgery was more common in patients who did not benefit from surgery (P = .034). No independent predictors of outcome were identified in a regression analysis.

CONCLUSIONS

This is the second-largest study on the treatment of Tarlov cysts ever published. Operative treatment in a selected patient population will likely produce improvement in the symptoms when balanced with the complication rate and profile of surgery. Preoperative lower back or sacral pain is a potential indicator for improvement after surgery.

Endoscopic transforaminal treatment of a thoracic perineural cyst: a case report

BACKGROUND AND IMPORTANCE

To describe the first case of a thoracic perineural cyst successfully treated using a direct thoracic transforaminal endoscopic approach.

METHODS

Case report.

CLINICAL PRESENTATION

A 66-year-old male presented with right-sided radicular pain in a T4 distribution. MRI of the thoracic spine revealed a right T4 perineural cyst caudally displacing the root in the T4-5 foramen. He had failed attempts at nonoperative management. The patient underwent an all endoscopic transforaminal perineural cyst decompression and resection as a same-day surgical procedure. Postoperatively, the patient noted near complete resolution of the preoperative radicular pain. A thoracic MRI with and without contrast was performed 3 months after surgery and showed no evidence of the preoperative perineural cyst and no symptom recurrence was noted by the patient.

CONCLUSION

This case report presents the first safe and successful report of an all endoscopic transforaminal decompression and resection of a perineural cyst in the thoracic spine.

Percutaneous Biportal Endoscopic Fenestration for Symptomatic Foraminal Tarlov Cyst

Perineural (Tarlov) cysts are a common benign pathology in the lumbosacral area but are rarely symptomatic, even when compressing the spinal root. Despite the rarity of Tarlov cyst formation in the foramen of the spine, this type is more symptomatic than those in other sites due to the narrow space. We introduce a biportal endoscopic fenestration for symptomatic foraminal Tarlov cysts. We present the case of a 40-year-old woman experiencing radiating pain in her right lower leg for 4 years. On seeking treatment, her great toe and ankle plantar flexion power had decreased. Magnetic resonance imaging revealed a cystic mass located in the L5-S1 intervertebral foramen that compressed the lumbar nerve root. Partial laminotomy was performed using a percutaneous biportal endoscopic system with a far lateral approach. An oval cystic mass of 2.6×1.1 cm was identified on high-definition images. Partial bone and foraminal ligament removal and cystic membrane fenestration were performed for nerve decompression. After decompression, the patient's motor weakness and radiating pain improved. Due to high-definition images and the minimally invasive laminotomy procedures associated with percutaneous biportal endoscopic fenestration, a foraminal Tarlov cyst was fenestrated safely, and weakness arising from radiculopathy was resolved in the current case. [Orthopedics. 2023;46(2):e125-e128.].

Giant Tarlov Cyst presenting as pelvic mass: Often doing less is better

Background

Tarlov cysts are sacral perineural cysts arising between the peri and endoneurium of the posterior spinal nerve root at the Dorsal Root Ganglion and have a global prevalence rate of 4.27%. These are primarily asymptomatic (only 1% with symptoms) and typically arise in females between the ages of 50-60. Patients' symptoms include radicular pain, sensory dysesthesias, urinary and/or bowel symptoms, and sexual dysfunction. Non-surgical management with lumbar cerebrospinal fluid drainage and computerized tomography-guided cyst aspiration typically provide only months of improvement before recurring. Surgical treatment includes a laminectomy, cyst, and/or nerve root decompression with fenestration of the cyst and/ or imbrication. Early surgery for large cysts provides the longest symptom-free periods.

Case Description

A 30-year-old male presented with a very large magnetic resonance-documented Tarlov cyst (Nabors Type 2) arising from bilateral S2 nerve root sheaths with marked pelvic extension. Although he was initially treated with a S1, S2 laminectomy, closure of the dural defect, and excision/marsupialization of the cyst, he later required placement of a thecoperitoneal shunt (TP shunt).

Conclusion

A 30-year-old male with large Nabors Type 2 Tarlov cyst arising from both S2 nerve root sheaths required a S1-S2 laminectomy, dural closure/marsupialization, and imbrication of the cyst, eventually followed by placement of a TP shunt.

Microsurgical sealing for symptomatic sacral Tarlov cysts: a series of 265 cases

OBJECTIVE

Tarlov cysts (TCs) are a common cystic entity in the sacral canal, with a reported prevalence between 1.5% and 13.2%; 10%-20% of patients are symptomatic and need appropriate clinical intervention. However, the choice of treatment remains controversial. The goal of this study was to describe a new microsurgical sealing technique for symptomatic sacral TCs (SSTCs) as well as its long-term outcomes.

METHODS

Microsurgical sealing was performed using a short incision, leakage coverage with a piece of autologous fat, and cyst sealing with fibrin glue. Postoperative data were collected at three stages: discharge, 1-year follow-up, and a follow-up of 3 years or more. According to the improvement in neurological deficits and degree of pain relief, outcomes were divided into four levels: excellent, good, unchanged, and deteriorated.

RESULTS

A total of 265 patients with SSTCs were treated with microsurgical sealing from January 2003 to December 2020. The mean follow-up was 44.69 months. The percentages of patients who benefited from the operation (excellent and good) at the three stages were 87.55%, 84.89%, and 80.73%, respectively, while those who received no benefit (unchanged and deteriorated) were 12.45%, 15.11%, and 19.27%, respectively. Of the patients with postoperative MRI, the cysts were reduced in size or disappeared in 209 patients (94.14%). CSF leakage from the wound was observed in 15 patients, and 4 patients experienced an infection at the incision. There were no cases of new-onset nerve injury or aseptic meningitis after the operation.

CONCLUSIONS

SSTC patients undergoing microsurgical sealing had persistently high rates of symptom relief and few postoperative complications. Microsurgical sealing is an effective, simple, and low-risk method for treating SSTCs.

Management of Symptomatic Sacral Perineural Cysts: A New Surgical Method

BACKGROUND

Microsurgical techniques are increasingly being recommended for the treatment of symptomatic Tarlov cysts (TCs) due to improved long-term outcomes compared to those of other strategies. However, these techniques are associated with a high risk of cyst recurrence and cerebrospinal fluid (CSF) leakage, resulting in the surgical strategy of TCs remaining controversial. We hypothesize that incomplete closure of the ostium between the cyst and the subarachnoid space is the probable cause of surgical failure. Accordingly, we present a novel method of cyst separation and ostium closure that aims to block the ostium more firmly and reliably.

METHODS

Thirty-five consecutive patients (21 females) underwent the modified ostium obstruction surgery due to symptomatic TCs. We collected and compared their outcomes at the final follow-up to evaluate the surgical effect.

RESULTS

Thirty-five patients had 74 TCs (S2 level, 48.7%; mean diameter, 2.0 ± 1.0 cm); ostia nerve root fibers were found in all TCs. The mean follow-up duration was 37.8 (range, 13.5-76.8) months. At the final follow-up, 33 patients experienced complete or substantial resolution of the preoperative symptoms. The symptom with the highest improvement rate was radicular pain. Both the modified evaluation criteria for the efficacy of lumbar function criterion and Japanese Orthopedic Association score 29 showed an overall improvement rate of 94.3%. Two patients experienced surgery-related neurological dysfunction. No cyst recurrence or CSF leakage was observed. Magnetic resonance imaging showed that all cysts disappeared or significantly reduced postoperatively.

CONCLUSIONS

The microscopic fenestration of cysts and modified ostium obstruction described herein is a safe and effective strategy for management of patients with symptomatic TCs and is associated with a low incidence of cyst recurrence and CSF leakage since it achieves complete closure of cyst ostium.

Case report: Epidural blood patches are effective in treating intracranial hypotension due to a subarachnoid-pleural fistula

Background

Intracranial hypotension (IH) is usually associated with cerebrospinal fluid (CSF) leakage and/or CSF hypotension, and epidural blood patch (EBP) therapy has been proven to be effective for treating spontaneous IH and post-dural puncture headaches. Tarlov cysts (TCs) are common lesions of the sacral spine. They have rarely been reported in thoracic locations and are even less common in the posterior mediastinum, which can lead to their misdiagnosis as neurogenic tumors.

Case presentation

Here, we report the case of a 60-year-old woman who developed an orthostatic headache after the thoracoscopic resection of a TC in the posterior mediastinum that was presumed to be a schwannoma preoperatively. The patient was finally diagnosed with IH caused by a subarachnoid-pleural fistula (SPF) and was cured by targeted EBP treatment.

Conclusion

This is a case to show that a single targeted EBP treatment is effective for a patient with IH caused by an SPF after thoracoscopic resection of a TC. This case reminds us to be vigilant that a TC may be masquerading as a posterior mediastinal neurogenic tumor, and a detailed examination should be performed to identify it before deciding on a surgical procedure. In addition, postural headache after thoracoscopic spinal surgery should be alert to the possibility of IH induced by an SPF. Once it occurs, early treatment is necessary, and targeted EBP treatment can serve as a safe and effective alternative when conservative treatment fails.

Novel wrapping surgery for symptomatic sacral perineural cysts

OBJECTIVE

Perineural cysts, also called Tarlov cysts, are dilatations of the nerve root sleeves commonly found in the sacrum. The majority of the cysts are asymptomatic and found incidentally on routine spine imaging. Symptomatic sacral perineural cysts (SPCs) that induce intractable low-back pain, radicular symptoms, and bladder/bowel dysfunction require surgery. However, the surgical strategy for symptomatic SPCs remains controversial. The authors hypothesized that the symptoms were caused by an irritation of the adjacent nerve roots caused by SPCs, and developed a wrapping surgery to treat these cysts.

METHODS

Seven patients with severe unilateral medial thigh pain and ipsilateral SPCs were included. Preoperative MRI showed that the cysts were severely compressing the adjacent nerve roots in all patients. After a partial laminectomy of the sacrum, the SPCs were punctured and CSF was aspirated to reduce their size, followed by dissection of the adjacent nerve roots from the SPCs. The SPCs were then wrapped with a Gore-Tex membrane to avoid reexpansion.

RESULTS

All 7 patients experienced substantial relief of their symptoms. The average numeric rating scale pain score was reduced from an average preoperative value of 7.9 to 0.6 postoperatively. Postoperative MRI showed that all cysts were reduced in size and the adjacent nerve roots were decompressed. Regrowth of the treated cysts or recurrence of the symptoms did not occur during the entire follow-up period, which ranged from 39 to 90 months. No complications were noted.

CONCLUSIONS

The authors' new wrapping technique was effective in relieving radicular symptoms for patients with symptomatic SPCs. The results suggested that the symptoms stemmed from compression of the adjacent nerve roots caused by the SPCs, and not from the nerve roots in the cysts.

Tarlov cysts in back pain patients: prevalence, measurement method and reporting points

OBJECTIVE

Determining the prevalence of Tarlov cysts in low back pain patients.

METHODS AND MATERIALS

The picture archiving & communication system (PACS) & hospital information system (HIS) of a corporate hospital were retrospectively analyzed to determine the percentage of Tarlov cysts among patients undergoing spinal MRI for back pain over 3 years (January 2017 to December 2019).

RESULTS

384 patients had undergone spinal MRI for back pain over the study period, and 25 of them (6.51%) had Tarlov cysts. Vast majority (15 cases) showed cysts located at S2/S3 level, and few were found at S1/S2 and other levels. Single cysts were found in most (=18) of the cases, while 7 cases of multiple / bilateral cysts were found. Cyst dimensions were higher in craniocaudal than anteroposterior or transverse directions. In case of multiple cysts, one or two cysts were noted as dominant, having higher dimensions than the others. The study data revealed no gender or age predilection.

CONCLUSIONS

We conclude that including the entire sacrum with a T2 sagittal sequence in all MRI for low back pain can increase detection of Tarlov cysts, and thereby provide more data for further analysis.

ADVANCES IN KNOWLEDGE

We propose the concept of one "dominant" cyst when there are multiple Tarlov cysts. We recommend that diameter or size of Tarlov cysts be specified to their craniocaudal dimension. We also suggest reporting points for contextual structured reporting, viz. presence or absence of bony scalloping, neural foraminal narrowing, nerve root compression or extraforaminal extension.

Elimination of the check-valve mechanism of the sacral Tarlov cyst using a rotation flap technique in a pediatric patient: technical note

OBJECTIVE

Symptomatic Tarlov cysts in children are not sufficiently reported and treatment methods for Tarlov cysts are still controversial. The goal of this manuscript is to introduce a new variation of the surgical technique.

METHODS

We performed surgery to eliminate the one-way check valve mechanism of the Tarlov cyst in a 7-year-old female who presented with urinary and fecal incontinence. A relatively large S3 nerve root cyst showed a one-way check valve on computed tomography myelography. The inlet of the check valve was enlarged with rotation flap reconstruction.

RESULTS

Two months after surgery, the patient had established normal sphincter control. MRI performed two years later showed that the treated cyst was collapsing, and no recurrence occurred.

CONCLUSIONS

Rotation flap enlargement of the check valve inlet is a safe and efficacious option for the treatment of pediatric patients with sacral Tarlov cysts.

Symptomatic perineural cyst after spontaneous subarachnoid hemorrhage: A case report

RATIONALE

Tarlov or perineurial cysts are nerve root lesions often found in the sacral region. Most perineural cysts (PCs) remain asymptomatic throughout a patient's life. While their pathogenesis is still unclear, trauma resulting in hemorrhaging into subarachnoid space has been put forward as a possible cause of these cysts. Recently, we worked with a patient experiencing symptomatic PCs after spontaneous subarachnoid hemorrhage.

PATIENT CONCERNS

A 45-year-old man had a coil embolization procedure performed after being diagnosed with a subarachnoid hemorrhage from a ruptured anterior communicating artery. His symptoms were relieved after the procedure, but 7 days later he reported worsening pain in the left perineal area. The pain was intermittent at its onset and exacerbated by sitting, walking, and coughing.

DIAGNOSES

Two weeks after the embolization procedure, a lumbar spine MRI revealed 2 PCs at the S1 and S2 level affecting the left S2 root with high signal intensity in T2 and T1 images, suggestive of bleeding within the cyst.

INTERVENTIONS

We operated using a posterior approach. Cyst fenestration was done after S1 laminectomy. We aspirated approximately 1 cc of old blood.

OUTCOMES

His pain was relieved immediately after cyst removal and no neurologic deterioration occurred during the postoperative period.

LESSONS

Subarachnoid hemorrhage can be the source of the development of pain from asymptomatic PCs, making them symptomatic. Surgical extirpation is 1 treatment option for these symptomatic PCs.

Spinal arteriovenous fistula located in the filum terminale externa: A case report and review of the literature

A filum terminale arteriovenous fistula (FTAVF) is an extremely rare spinal arteriovenous fistula (AVF) and typically presents with myelopathy and conus medullaris syndrome caused by venous congestion in the spinal cord. Most reported FTAVFs are intradural pial AVFs with perimedullary drainage in the filum terminale interna. However, there are no reports of AVFs in the filum terminale externa (FTE). We describe a case involving a 68-year-old man with an AVF in the FTE who presented with progressive myelopathy and underwent successful endovascular treatment. We identified the specific shunt point by fusing postoperative computed tomography and magnetic resonance images. The features of the extradural sac AVF developed in the FTE may mimic those of a dural AVF with dural supply to the FTE covered by the dural component, unlike typical FTAVFs where the shunt develops at the pia mater. This case makes a significant contribution to the field by increasing the understanding of the clinical characteristics of an AVF that develops in the FTE and its angioarchitecture.

Myelographic CT, A Check-Valve Mechanism, and Microsurgical Treatment of Sacral Perineural Tarlov Cysts

OBJECTIVE

There is currently no consensus regarding surgical indications for symptomatic sacral perineural cysts.

METHODS

Nine patients with symptomatic sacral perineural cysts underwent microsurgery. All patients fulfilled the following criteria: (1) cyst sizes larger than 15 mm; (2) cysts show the "delayed inflow" and/or "delayed outflow" of contrast on myelographic computed tomography (CT), and (3) neurological symptoms correlate with the primary cyst.

RESULTS

On myelographic CT, all primary cysts showed the "delayed inflow" of contrast; the average cyst/thecal sac Hounsfield units (HU) ratio was 0.17. In 7 patients, the primary cyst showed "delayed outflow"; the average cyst/thecal sac HU ratio increased to 3.12 on images obtained 24 hours after contrast injection. Regarding the modified Rankin Scale, 67% of patients reported that their overall symptoms improved to normal activities after surgery. The most improved symptom was coccydynia (75% improvement, P = 0.017), followed by leg radiation pain (67% improvement, P = 0.027) and buttock pain (50% improvement, P = 0.068). Bowel/bladder dysfunction improved in 100% of patients, but newly developed in 1 patient (P = 0.32). Perineal pain only decreased in 33% (P = 0.41).

CONCLUSIONS

To the best of our knowledge, this is the first study to have performed a quantitative analysis of the dynamics of cerebrospinal fluid in sacral perineural cysts using myelographic CT. Sixty-seven percent of patients benefited from surgery; however, our criteria may not be a necessary and sufficient condition for patient selection because 33% did not respond to surgery despite the successful elimination of the check-valve.

Surgical management of sacral meningeal cysts by obstructing the communicating holes with muscle graft

BACKGROUND

The surgical indication and treatment of sacral meningeal cyst have not been well established and current methods are usually accompanied by complications and recurrence. The aim of this study is to discuss the treatment of symptomatic sacral meningeal cyst, by investigating the surgical results of our surgically treated patients, and minimize the complications and recurrence.

METHODS

We retrospectively reviewed all patients with symptomatic sacral meningeal cysts who were surgically treated by a single surgeon in the same institution from 2002 to 2017. All patients underwent the same operation by incising the cyst wall and obstructing the communicating hole with muscle graft, while the cyst wall was left untreated instead of resected or imbricated. The obstruction was verified by doing a Valsalva-like maneuver. The preoperative symptoms and signs, and the outcomes at most recent follow-up were rated and compared by Neurological Scoring System.

RESULTS

A total of 18 patients (7 male patients and 11 female patients, average age 42.3 years) were followed up for an average of 51.7 months. All patients had communicating holes linking the cysts and the dural sacs. The average preoperative neurological score was 19.7 ± 2.2, and it was improved to 23.2 ± 2.8 at the most recent follow-up (p < 0.01).

CONCLUSIONS

The sacral meningeal cyst originated from the communication with the dural sac. Surgical treatment of symptomatic sacral meningeal cysts can yield a long-term resolution of the appropriately selected patient's symptoms. Obstructing the communicating hole with muscle graft is an effective and simple method to obliterate the cyst. The incised cyst wall can be left untreated instead of resected or imbricated.

Surgical management of symptomatic Tarlov cysts: cyst fenestration and nerve root imbrication-a single institutional experience

BACKGROUND

Tarlov cyst disease is a collection of cerebrospinal fluid between the endoneurium and perineurium of spinal, usually sacral, nerve roots. These cysts can become symptomatic in 20% of patients, causing lower back pain, radiculopathy, bladder and bowel dysfunction necessitating medical or surgical intervention. Different surgical and non-surgical modalities have been described for the treatment of symptomatic Tarlov cysts. However, there has been no published study that examined types of surgical techniques side by side. Our study presents a preliminary experience in the surgical management of symptomatic Tarlov cysts using two surgical techniques: cyst fenestration and nerve root imbrication.

METHODS

Retrospective chart review and analysis was done for all patients who underwent surgical intervention for symptomatic Tarlov cyst(s) in the period 2007-2013. Operative reports, preoperative and postoperative clinic visit reports were reviewed. The surgical techniques of cyst fenestration and nerve root imbrication were each described in terms of intraoperative parameters, hospital course and outcome. Modified MacNab criteria were used for evaluation of the final clinical outcome.

RESULTS

Thirty-six surgical patients were identified. Three had repeat surgery (total of 39 operations). The median age was 51 years (range, 26-84 years). Eighty-six percent were females. The presenting symptoms were low back pain (94%), sensory radiculopathy (69%), bladder and bowel dysfunction (61%), sexual dysfunction (17%) and motor dysfunction (8%). Cyst fenestration was performed in 12 patients (31%) and nerve root imbrication was done in 27 (69%). All patients in the fenestration group but only 67% in the imbrication group had fibrin glue injection into the cyst or around the reconstructed nerve root. The overall surgery-related complication rate was 28%. The complication rate was 5/12 (42%) in the fenestration group and 6/27 (22%) in the imbrication group. At the time of the last clinic visit, improved clinical outcome was noted in 9/11 (82%) and 20/25 (80%) in the fenestration and the imbrication group, respectively.

CONCLUSIONS

Cyst fenestration and nerve root imbrication are both surgical techniques to treat symptomatic Tarlov cyst(s), and both can result in clinical improvement.

[Surgical treatment of sacral Tarlov cysts: about 20 cases]

Tarlov cyst or perineural cyst is a local dilation of the subarachnoid space formed within the nerve root and filled with cerebrospinal fluid. There is no consensus on the best treatment of syntomatic sacral perinervous cysts. Many methods have been used to treat these symptomatic lesions, with variable results. We report a case series including 20 patients undergoing surgery for sacral Tarlov cyst. Our results were satisfactory; 80% of patients improved without neurological worsening in the post-operative period. Our surgical technique (sacral laminectomy+cyst puncture+establishment of dural sheat) described for the first time in this study seems to have been effective in the 20 cases reported in our study.

Management of perineural (Tarlov) cysts: a population-based cohort study and algorithm for the selection of surgical candidates

Objective

Perineural cysts, also known as Tarlov cysts, are cerebrospinal fluid-filled growths that develop at the intersection of a dorsal root ganglion and posterior nerve root. They are typically an asymptomatic and incidental finding during routine spine imaging. For symptomatic perineural cysts, there is little evidence on which treatment is most effective or when it is indicated. The aim of this study was to review our experience from a population-based cohort of patients with symptomatic perineural cysts and to propose an algorithm that could be used in the selection of surgical candidates.

Methods

A retrospective review was conducted of all adult (≥ 15 years) patients with symptomatic perineural cysts who were referred to Karolinska University Hospital between 2002 and 2018.

Results

Thirty-nine patients were included. The most common symptom was sciatica (n = 22). Cyst aspiration was performed in 28 patients, 24 of whom showed clinical improvement and were offered surgery. Microsurgical cyst fenestration was performed in 17 patients, 16 of whom showed clinical improvement at long-term follow-up. There were no surgical complications. Ten of the patients who were offered surgery chose to be treated conservatively instead, four of whom showed progression of symptoms at long-term follow-up.

Conclusions

Microsurgical cyst fenestration seems to be a safe and effective option for symptomatic relief in patients with perineural cysts. Based on the results from our series and those of others, we propose an algorithm for the selection of surgical candidates.

Electronic supplementary material

The online version of this article (10.1007/s00701-019-04000-5) contains supplementary material, which is available to authorized users.

Tarlov cyst-a rare lesion in children: case report

Perineural cysts, also known as Tarlov cysts, are benign lesions increasingly found in patients undergoing neuroimaging studies. These cysts can very rarely be identified in children and even then, they are not so likely to be responsible for some neurological deficit. It seems to be of scientific and clinical importance to present a pediatric case with Tarlov cyst. We report a case of a patient, a 7-year-old boy, previously treated for nocturnal enuresis (bedwetting), who later developed signs and symptoms of classic urinary incontinence. Magnetic resonance imaging (MRI) showed a relatively large extradural cyst at the level of S2. The cyst was approached by laminectomy of L5 to S2, excised, and completely removed from the belonging nerve root. The patient has established normal sphincter control without even a single episode of involuntary discharge of urine. A surgery is a powerful, safe, and efficacious option for treatment in pediatric patients with sacral Tarlov cysts.

A Giant Tarlov Cyst Presenting with Hydronephrosis in a Patient with Marfan Syndrome: A Case Report and Review of the Literature

BACKGROUND

Giant Tarlov cysts are always symptomatic and mimic many serious pathologic entities. We present the largest, to our knowledge, reported Tarlov cyst.

CASE DESCRIPTION

A 33-year-old woman with Marfan syndrome suffered from right kidney hydronephrosis because of ureter obstruction, for which she was treated with nephrostomy. Her neurologic examination was unremarkable. The role of magnetic resonance imaging in the management of this case is described. Absence of intractranial hypotension symptoms after cerebrospinal fluid (CSF) overdrainage suggested the presence of a valve-like mechanism. The patient was planned for surgical cyst remodeling by the application of titanium clips. The cyst's neck was exposed through an L5-S2 laminectomy. L5 and S1 laminae were severely eroded. CSF leaked out of the underlying, bulging, and thinned dura at each attempt for clip application. Intraoperatively, multiple responses from the S1, S2, and S3 roots were simultaneously recorded at each stimulation. Therefore, we decided to abandon this technique and performed a nonwatertight duroplasty followed by a layered wound closure instead. A week later, the patient received a lumbar-peritoneal shunt. The patient remained neurologically intact, the cyst shrunk, and the nephrostomy was removed.

CONCLUSIONS

Indirect evidence was helpful to assess for the presence of a valve-like mechanism. Intraoperatively, the surgeon must keep on high alert for sacral erosion to avoid inadvertent dural tear and rootlet injury. Finally, lumboperitoneal diversion remains a valid alternative in the management of our giant Tarlov cyst because it reduced the intracystic pressure that resulted in cyst regression.

Incidentalomas in Spine and Spinal Cord Imaging

Incidentalomas are common in magnetic resonance imaging (MRI) of the spine. These incidental findings (IFs) can be seen involving the spinal cord, nerve root, vertebral body, posterior arch and the extraspinal region. This review article describes the imaging findings, stratifies the IFs similar to the computed tomography (CT) colonography reporting and data system and briefly mentions the current recommendations for further evaluation and management of IFs. Radiologists are the first to detect these lesions, suggest further evaluation and management of IFs. It is therefore mandatory for them to be aware of recommendations in clinical practice in order to avoid increased patient anxiety, excessive healthcare expenditure and inadvertent therapeutic procedures.

Shrinking of a Tarlov cyst

A 65-year-old patient presenting with left labial and perirectal pain was diagnosed with bilateral Tarlov cysts. Upon treatment of the left Tarlov cyst (the right was asymptomatic) using image-guided aspiration and subsequent injection of the cyst with fibrin sealant, the cyst reduced in size. To our knowledge, there are currently no other documented cases in which the Tarlov cyst reduced in size following this procedure. This case would seem to suggest that clinicians are poorly informed with regard to Tarlov cysts. These cysts are more common in Caucasian women, many of whom are told their cysts are not responsible for their pain or that they are not treatable. However, there is clear evidence that some Tarlov cysts are symptomatic and minimally invasive procedures have been developed to treat them. As they primarily occur in women, it is possible gender bias may also play a role in the delayed diagnosis of the patient’s pain.

A systematic comparative outcome analysis of surgical versus percutaneous techniques in the management of symptomatic sacral perineural (Tarlov) cysts: a meta-analysis

OBJECTIVE

Symptomatic perineural or Tarlov cysts (TCs) are a rare cause of chronic low-back pain. Given the rarity of the disease, there is no literature consensus regarding the optimal management of these cysts.

METHODS

The authors conducted a systematic comparative outcome analysis of symptomatic TCs treated with surgery (group A, 32 studies, n = 333) or percutaneous interventions (group B, 6 studies, n = 417) analyzing the demographic characteristics, baseline characteristics of the cysts, clinical presentations, types of interventions, complication rates, and the recurrence rate in both treatment groups. The literature search was performed using the PubMed, MEDLINE, Cochrane, and Ovid databases up to 2018. The MeSH search terms used were "Tarlov cyst," "sacral perineural cyst," "sacral nerve root cyst," "meningeal cyst of the sacral spine," "extra meningeal cyst with spinal nerve root fibers," "spinal extradural arachnoid pouch," and "cyst of the sacral nerve root sheath." The authors used statistical tests for two proportions using the "N-1" chi-square test with the free version of MedCalc for Windows for comparison among the groups.

RESULTS

Overall symptomatic improvement was reported in 83.5% of patients in both groups; however, exacerbation of preprocedural symptoms was significantly higher in group B than group A (10.1% vs 3.3%, p = 0.0003). The overall complication rates in the surgical and nonsurgical groups were 21% and 12.47%, respectively. Transient sciatica was the most common complication in both groups (17% vs 8%, respectively; p = 0.017). The incidence of cyst recurrence was much lower in group A than group B (8% vs 20%, p = 0.0018). The mean follow-up duration for the surgical group was 38 ± 29 months (25 studies, n = 279), while that for the nonsurgical group was 15 ± 12 months (4 studies, n = 290) (p < 0.0001).

CONCLUSIONS

The authors noted that although the surgical interventions were associated with higher postprocedural complication rates, long-term efficacy and success in terms of cyst resolution were superior following surgery compared to percutaneous procedures in the management of symptomatic TCs. There was no difference in symptom recurrence with either of the techniques.

Perineural cyst with intracystic hemorrhage following aneurysmal subarachnoid hemorrhage: A case report

RATIONALE

Most perineural cysts are asymptomatic and discovered incidentally at the time of imaging. Although enlargement of the perineural cyst (PC) through a ball-valve mechanism and resultant compression of the adjacent neural or bony structures are known to be a source of pain in PCs, the reason why asymptomatic PCs become symptomatic is unclear. The authors report a case of PC, which was presumed to become symptomatic after subarachnoid hemorrhage without enlargement of the pre-existing PC.

PATIENT CONCERNS

A 47-year-old woman complained of lumbosacral pain after neck clipping for a ruptured cerebral aneurysm.

DIAGNOSES

Magnetic resonance imaging (MRI) revealed a PC with intracystic hemorrhage at the S2 level. In comparison with the size of the PC on computed tomography performed 3 years ago, there was no change in the size. Electrodiagnostic studies performed 6 weeks after the onset of the pain showed subacute right S2 radiculopathy.

INTERVENTIONS

With conservative treatment, her pain gradually diminished.

OUTCOMES

When the lumbosacral pain improved, follow-up MRI showed that a fluid-fluid level within the PC disappeared.

LESSONS

Hemorrhage from the subarachnoid space, such as spontaneous aneurysmal SAH, into the pre-existing PC can cause an asymptomatic PC to become symptomatic without getting enlarged. Stretching of the nerve root due to hemorrhage or irritation of the nerve root due to an inflammatory reaction to blood products can make asymptomatic PCs symptomatic without enlargement of PCs.

Growth of Lumbosacral Perineural (Tarlov) Cysts: A Natural History Analysis

BACKGROUND

Tarlov cysts (TC) are commonly found spinal perineural cysts. Symptomatic TCs are rare, however, and there is no consensus on their pathogenesis and optimal management.

OBJECTIVE

To characterize cyst growth in patients with symptomatic TCs.

METHODS

This is a retrospective cohort study of 28 subjects, evaluated for symptomatic TCs (2011-2017). Each of the subjects had multiple magnetic resonance imaging (MRIs) across time and was included in a natural history analysis.

RESULTS

A total of 42 TCs were identified across the 28 subjects, of which 7 cysts (17%) across 5 subjects demonstrated growth. Across a mean follow-up of 4.7 ± 1.8 years, TCs grew at a relative rate of 2.9 ± 2.6% in the anteroposterior, 4.3 ± 3.8% in the craniocaudal, and 1.4 ± 1.4% in the transverse dimensions per year. None of the cysts decreased in size between successive MRIs. Symptoms of cerebrospinal fluid (CSF) hypotension (positional headaches) were positive predictors of prior cyst growth on logistic regression (P = 0.02, odds ratio = 10). A total of 2 of the 5 subjects were initially asymptomatic from their TCs, and developed symptoms during the period of cyst growth, whereas 2 others experienced worsening of their symptoms during cyst growth.

CONCLUSION

We report on the growth of TCs, which is consistent with a widely-held theory that hydrostatic and pulsatile forces of CSF along with a ball-valve phenomenon allow for continuous dilation of TCs.

Radiculoplasty with reconstruction using 3D-printed artificial dura mater for the treatment of symptomatic sacral canal cysts: Two case reports

RATIONALE

Currently, interventional injection of albumin glue and nerve sleeve plasty by cyst excision is the main treatment for sacral cysts. However, albumin glue can only be used in patients with partial cystic neck stenosis, and surgical treatment may result in postoperative complications such as numbness and cyst recurrence. Here, a modified radiculoplasty is presented, in which the lamina is restored with the nerve root wrapped with 3-dimensional (3D)-printed artificial dura mater.

PATIENT CONCERNS

The first patient, a 28-year-old man, had been complaining of aggravated perineal pain for 8 months a visual analog scale (VAS) score of 7. Sacrococcygeal magnetic resonance imaging (MRI) revealed multiple sacral canal cysts. The second case, a 48-year-old woman, has been complaining of lumbosacral and left leg pain for 1 month (VAS score of 7). Physical examination showed hyperalgesia below the right sacrum 2 level. Sacrococcygeal MRI and computed tomography (CT) revealed multiple sacral canal cysts and a calcified lesion in the cyst.

DIAGNOSES AND INTERVENTION

The first patient underwent radiculoplasty with reconstruction using 3D-printed artificial dura mater, with 3 cysts treated and the lamina restored. Four cysts of the second patients were treated, including 1 bone-occupying lesion. Radiculoplasty with reconstruction using 3D-printed artificial dura mater was used for the cysts and the lamina was restored OUTCOMES:: The postoperative VAS score was 0 to 2 points in the 2 patients. No postoperative infection or new neurological dysfunction was observed. Postoperative MRI showed no cysts, with lamina restoration. After 6 months, the VAS score was 0, and MRI showed no recurrence.

LESSONS

Radiculoplasty with reconstruction using 3D-printed artificial dura mater and lamina restoration could be beneficial for the treatment of symptomatic sacral canal cysts.

Effectiveness of Surgical Treatment for Tarlov Cysts: A Systematic Review of Published Literature

OF BACKGROUND DATA

In the general population, it has been estimated that 1.5% of people have ≥1 Tarlov cysts, with about 13% of those being symptomatic. Despite a range of options for treatment, there is debate about when, and how to optimally treat individuals with Tarlov cysts among clinicians, and among policy decision makers.

OBJECTIVE

To summarize the current evidence on surgical treatment of Tarlov cysts.

STUDY DESIGN

A systematic review was completed.

METHODS

Nine databases were searched. Abstracts and full-texts were assessed by 2 reviewers. To be included, studies had to assess safety, efficacy, or effectiveness of treating Tarlov cysts, had to be written in English or French, and had to be a randomized, quasi-randomized, observational cohort, case control, or case series design including ≥2 participants. Logistic regression analysis was undertaken on the patient-level data collected to assess the association of patient and cyst characteristics on treatment success.

RESULTS

In total, 31 studies were included in this systematic review; all were case series. Among the 646 participants included in these 31 studies, 210 experienced complete resolution of symptoms (32%), 327 had partial resolution (50%), 106 did not have any improvement or worsening of symptoms (16%), and 3 had their symptoms worsen after surgery (0.4%). A number of adverse events were reported after surgery; however, all were temporary. The analysis of 49 patients with data on cyst size resulted in the odds of complete resolution of symptoms being lower for patients with larger cysts (odds ratio=0.53, P-value=0.107) although this finding is not statistically significant. For those with a cyst >1.5 cm the odds of complete resolution were (odds ratio=0.36, P-value=0.190) compared with those with a cyst <1.5 cm.

CONCLUSIONS

The evidence suggests that surgery for symptomatic Tarlov cysts may be an effective option for partially or completely relieving symptoms. Contrary to previous findings larger cysts were not associated with completely relieving symptoms.

Resection and imbrication of symptomatic sacral Tarlov cysts: A case report and review of the literature

Background:

Symptomatic Tarlov cysts are extremely rare, and there is no consensus regarding their optimal surgical management. Here, we encountered a patient with a symptomatic sacral Tarlov cyst and reviewed the appropriate literature.

Case Description:

A 40-year-old male presented with right lower extremity pain and hypoesthesia in the right S2 dermatome. The lumbosacral MR demonstrated a right S2 Tarlov cyst compressing the S2–S3 perineural sheaths. After the patient underwent microscopic cystectomy with obliteration of the subarachnoid connection to the cyst, the patient's symptoms resolved. Here, we reviewed our operative approach, and others proposed in the literature for the surgical management of these lesions.

Conclusions:

Here, we present a 40-year-old male who was symptomatic from a right S2 Tarlov cyst compressing the S2–S3 perineural sheaths and successfully underwent microscopic cystectomy with obliteration of the subarachnoid connection. Additionally, the appropriate Tarlov cyst literature was reviewed.

Management of symptomatic sacral perineural cysts with microsurgery and a vascularized fasciocutaneous flap

Background

The optimal treatment of symptomatic perineural (Tarlov) cysts is controversial. Numerous surgical techniques have been proposed with conflicting results. A series of Tarlov cysts treated with a novel surgical approach is presented.

Methods

Patients with surgically treated symptomatic perineural cysts during 2013-2016 were included. The main indications for surgery were persistent radicular symptoms, pelvic pain, urinary and/ or bowel disturbances. At surgery, the cyst was opened and fenestrated. The cyst wall was then closed with packing, fibrin glue and a pedicled vascularized fasciocutaneous flap rotated into the area for obliteration of the dead space. Patients were followed-up with clinical visits and repeat magnetic resonance imaging (MRI) scans.

Results

Seven consecutive patients were included. The mean age was 50.3 years (range, 25-80 years) and the mean duration of symptoms was 49.3 months (range, 3-130 months). With one exception, all patients had urine and/or bowel problems (incontinence) preoperatively. A lumbar drain was inserted in five patients. The mean follow-up period was 15.4 months. Symptoms improved in 4/7 patients, in two cases no clinical difference was noted while one patient deteriorated. In two cases, a spinal cord stimulator was eventually implanted. In all seven cases, a significantly decreased cyst size was noted on MRI.

Conclusions

Cyst fenestration and the use of a vascularized fasciocutaneous flap successfully obliterated all cysts, with satisfactory clinical efficacy. Larger and comparative studies are warranted to clarify the long-term effects of this surgical technique in patients with symptomatic Tarlov cysts.

A novel technique for managing symptomatic spinal cysts using epiduroscopic neural laser decompression: technical note and preliminary results

BACKGROUND

Benign spinal cysts are relatively common, but can cause significant pain. However, consensus regarding the best method for treating these cysts has not been established. We aimed to examine the usefulness of epiduroscopic neural laser decompression (ENLD), a novel percutaneous treatment, for treating lumbo-sacral cysts.

METHODS

Ten patients (6 men, 4 women; mean age 45.5 years) with benign lumbo-sacral cysts underwent ENLD. The lumbo-sacral cysts were caused by multiple pathophysiologies and displayed different characteristics. Cysts were evaluated using a recorded epiduroscopic procedure video, magnetic resonance imaging (MRI), and electronic medical records. In all patients, MRI identified cysts with well-defined margins that were compressing the nerves in the lumbo-sacral region and were associated with the pain symptoms of the patients. Retrospectively, we reviewed a series of consecutive patients who underwent surgery (two with discal cysts, four with facet cysts, and four with Tarlov cysts). Low back/leg pain was evaluated using a 1-10 visual analog scale. Functional improvement was evaluated using Oswestry Disability Index scores. Outcomes were evaluated pre- and post-operatively and 1 year post-surgery.

RESULTS

Patients were examined between May 2016 and August 2017. Average pain scores improved from 4.7 pre-surgery to 1.8 post-surgery (low back; p < .001) and from 5.8 pre-surgery to 1.6 post-surgery (leg; p < .001). Disability scores decreased from 27.2% pre-surgery to 14.6% post-surgery.

CONCLUSION

Currently, no standard treatment strategy for symptomatic spinal cysts exists. These results show that ENLD using a Holmium: YAG laser can be useful in treating symptomatic benign spinal cysts.

TRIAL REGISTRATION

Not applicable as this is a retrospective chart review.

Fine Configuration of Thoracic Type II Meningeal Cysts: Macro- and Microscopic Cadaveric Study Using Epoxy Sheet Plastination

STUDY DESIGN

A cadaveric study OBJECTIVE.: The aim of this study was to analyze the in situ macro- and microscopic configuration of the type II cyst and its anatomic relationship with surrounding structures.

SUMMARY OF BACKGROUND DATA

The lack of consensus of surgical strategy to manage symptomatic type II meningeal cysts (Tarlov cysts) is because our knowledge of type II cyst anatomy remains incomplete. It has been assumed that the cyst communicates with the subarachnoid space via microconnections. Till date, however, no direct evidence demonstrates the existence of the microconnections, although delayed contrast filling of type II cysts is commonly observed in CT myelography.

METHODS

Three type II meningeal cysts analyzed in this study were incidentally found in one of 16 plastinated spines. The spine was from an 89-year-old female cadaver and plastinated as a set of 164 transverse sections with a thickness of 2.5 mm. The sections were examined under a stereomicroscope.

RESULTS

Three type II cysts were in the thoracic spine and had a common feature that a clearly identifiable cyst neck connected the cyst body to the subarachnoid space. The dorsal root of the spinal nerve was centered in the cyst neck but spread over the cyst body or traversed the cyst cavity. The meningeal opening of the cyst was located above the inferior border of the vertebral pedicle, thus, the cyst neck hugged around the pedicle and sharply turned inferolaterally into the intervertebral foramen. The cyst body was halted by the dorsal ganglion.

CONCLUSION

This study reveals in situ macro- and microscopic configuration of the type II cyst and its relationship with the structures and suggests that it may be feasible to localize and ligate the cyst neck for surgical management of type II cysts.

LEVEL OF EVIDENCE

3.

Microsurgical treatment of sacral perineural (Tarlov) cysts: case series and review of the literature

OBJECTIVE

Tarlov cysts (TCs) occur most commonly on extradural components of the sacral and coccygeal nerve roots. These lesions are often found incidentally, with an estimated prevalence of 4%–9%. Given the low estimated rates of symptomatic TC and the fact that symptoms can overlap with other common causes of low-back pain, optimal management of this entity is a matter of ongoing debate. Here, the authors investigate the effects of surgical intervention on symptomatic TCs and aim to solidify the surgical criteria for this disease process.

METHODS

The authors performed a retrospective review of data from consecutive patients who were surgically treated for symptomatic TCs from September 2011 to March 2013. Clinical evaluations and results from surveying pain and overall health were used. Univariate statistical analyses were performed.

RESULTS

Twenty-three adults (4 males, 19 females) who had been symptomatic for a mean of 47.4 months were treated with laminectomy, microsurgical exposure and/or imbrication, and paraspinous muscle flap closure. Eighteen patients (78.3%) had undergone prior interventions without sustained improvement. Thirteen patients (56.5%) underwent lumbar drainage for an average of 8.7 days following surgery. The mean follow-up was 14.4 months. Univariate analyses demonstrated that an advanced age (p = 0.045), the number of noted perineural cysts on preoperative imaging (p = 0.02), and the duration of preoperative symptoms (p = 0.03) were associated with a poor postoperative outcome. Although 47.8% of the patients were able to return to normal activities, 93.8% of those surveyed reported that they would undergo the operation again if given the choice.

CONCLUSIONS

This is one of the largest published studies on patients with TCs treated microsurgically. The data suggest that patients with symptomatic TCs may benefit from open microsurgical treatment. Although outcomes seem related to patient age, duration of symptoms, and extent of disease demonstrated on imaging, further study is warranted and underway.

Sacral perineural cyst mimicking inflammatory low back pain

This case describes a 46-year-old woman with local pelvic and perineal pain, persisting for 2 years at presentation. The pain worsened during the night and morning and was alleviated during daily activities. Low back pain was associated with morning stiffness lasting longer than 2 h. Sometimes, she felt pain and numbness along her left S1 dermatome, without overt bladder or bowel incontinence. Lasegue's sign was negative. Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were elevated (35 mm/h and 9.4, respectively) and Mennel's sign was present on both sides, indicating possible inflammation of the sacroiliac joints. However, radiographs of the lumbosacral spine and sacroiliac joints were normal. Magnetic resonance imaging (MRI) revealed a large spinal meningeal cyst in the sacrum (60 × 37 × 22 mm) consisting of multiple perineural cysts. The cyst eroded the surrounding sacral bone structures, narrowed several sacral foramina, and compressed neighboring nerve fibers. MRI findings on sacroiliac and hip joints were normal.

Treatment of 213 Patients with Symptomatic Tarlov Cysts by CT-Guided Percutaneous Injection of Fibrin Sealant

BACKGROUND AND PURPOSE

There has been a steady progression of case reports and a small surgical series that report successful surgical treatment of Tarlov cysts with concomitant relief of patients' symptoms and improvement in their neurological dysfunction, yet patients are still told that these lesions are asymptomatic by physicians. The purpose of this study was to analyze the efficacy and safety of intervention in 213 consecutive patients with symptomatic Tarlov cysts treated by CT-guided 2-needle cyst aspiration and fibrin sealing.

MATERIALS AND METHODS

This study was designed to assess outcomes in patients who underwent CT-guided aspiration and injection of ≥1 sacral Tarlov cyst at Johns Hopkins Hospital between 2003 and 2013. In all, 289 cysts were treated in 213 consecutive patients. All these patients were followed for at least 6 months, 90% were followed for 1 year, and 83% were followed for 3-6 years. The aspiration-injection procedure used 2 needles and was performed with the patients under local anesthesia and intravenous anesthesia. In the fibrin-injection stage of the procedure, a commercially available fibrin sealant was injected into the cyst through the deep needle (Tisseel VH).

RESULTS

One year postprocedure, excellent results were obtained in 104 patients (54.2% of patients followed), and good or satisfactory results were obtained in 53 patients (27.6%). Thus, 157 patients (81.8%) in all were initially satisfied with the outcome of treatment. At 3-6 years postprocedure, 74.0% of patients followed were satisfied with treatment. There were no clinically significant complications.

CONCLUSIONS

The aspiration-injection technique described herein constitutes a safe and efficacious treatment option that holds promise for relieving cyst-related symptoms in many patients with very little risk.