Spinal extradural meningeal cyst. Case report

Spinal extradural arachnoid cysts: A novel formation mechanism and dural defect location technology

Purpose

The formation mechanism of spinal extradural arachnoid cysts (SEACs) remains unclear. There are several hypotheses for the formation of SEACs, but none of them can fully explain its pathological findings and surgical procedures. In this study, we retrospectively analyzed the cases of SEACs, aiming to clarify the formation mechanism of SEACs. In addition, we summarize a concise method for locating dural defects preoperatively and formulate a putative explanation of this method.

Methods

The clinical data of 14 patients with SEACs underwent surgery in our hospital from January 2017 to December 2021 were retrospectively analyzed.

Results

Fourteen patients were identified during the study period. The cysts all spanned the T12/L1 segment, and dural defects were also located at the T12/L1 level (2 cases not recorded) as well as the middle or the upper-middle level of the cysts. Nine cases were treated with total cyst excision, 2 cases were treated with dural defect closure only, and 3 cases were treated with total cyst excision and dural defect closure. Histopathological examination demonstrated that the cyst wall contained both the arachnoid epithelial and compact fibrous connective tissue. The symptoms were relieved in all patients, and no recurrence was observed.

Conclusions

According to intraoperative and pathological findings, the dural outer layer cyst (DOLC) is a more reasonable hypothesis about SEACs formation. When CT myelography or cinematic MRI cannot determine the location of the dural defect preoperatively, it can be located according to the middle level of the SEACs with high accuracy.

Clinical Profile and Treatment Outcome of Spinal Epidural Arachnoid Cysts: A Systematic Review of Case Studies and Reports

Background A spinal epidural arachnoid cyst (SEAC) is a rare clinical entity. We performed a systematic review of the literature to obtain information regarding demographics, clinical presentation, treatment modalities, and outcome of SEACs.

Methods A literature search was performed by using the databases PubMed/Medline, PubMed Central, Embase, Cochrane Library, Ovid MEDLINE, and Ovid Medline In-Process. A total of 170 articles were found on literature search. We found 575 cases of SEAC since 1904 for inclusion in the review including three cases which were operated by us. We studied the patient characteristics, clinical features, and management strategies, and evaluated their outcome.

Results The average age of presentation was 30 years with a male:female ratio of 1.03:1. They are commonly seen in the thoracic region (42.3%). The length of cyst was more than two vertebral levels in 85.81%. Mean symptom duration was 29 months, with most common presentation being that of compressive myelopathy. A good clinical outcome was present in symptomatic patients who had a shorter symptom duration and underwent complete surgical excision of the SEAC. Age, sex, length of lesion, and presence of dural defect did not have a bearing on the surgical outcome.

Conclusion For thoracic compressive myelopathy in a young patient, SEAC should be kept as a differential diagnosis. Surgical complete excision of the cyst with meticulous closure of the dural defect is the standard in management for a good clinical outcome.

Multiple spinal extradural arachnoidal cysts: An uncommon cause of thoracic cord compression

Spinal extradural arachnoid cysts are one of the rare causes of symptomatic spinal cord compression. Among them, occurrence of multiple cysts at the same spinal segment is rarely described in the literature. They appear to be extradural outpouchings of arachnoid that communicate with the intraspinal sub-arachnoid space through a small defect in the dura, filled by cerebrospinal fluid. Pathogenesis of these lesions is still unclear. Surgical excision is considered as the gold standard treatment. We present a 7-year-old female child who presented with spastic paraparesis. Her magnetic resonance imaging showed a thoracic posterior extradural arachnoid cyst, whereas, intraoperatively we found multiple cysts, which were excised completely. Neurological symptoms gradually recovered after surgical decompression.

A symptomatic spinal extradural arachnoid cyst with lumbar disc herniation

Spinal epidural arachnoid cyst (EAC) is a rare, usually asymptomatic condition of unknown origin, which typically involves the lower thoracic spine. We report a case of posttraumatic symptomatic EAC with lumbar disc herniation. A 22-year-old man experienced back pain and sciatica after a traffic accident. Neurological examination revealed a right L5 radiculopathy. Magnetic resonance imaging demonstrated a cystic lesion at the L3 to L5 level and an L4-5 disc herniation; computed tomography myelography showed that the right L5 root was sandwiched between the cyst and the herniation. A dural defect was identified during surgery. The cyst was excised completely and the defect was repaired. A herniation was excised beside the dural sac. Histology showed that the cyst wall consisted of collagen and meningothelial cells. Postoperatively the symptoms resolved. Lumbar spinal EACs are rare; such cysts may arise from a congenital dural crack and grow gradually. The 6 cases of symptomatic lumbar EAC reported in the literature were not associated with disc herniation or trauma. In this case, the comorbid disc herniation was involved in symptom progression. Although many EACs are asymptomatic, comorbid spinal disorders such as disc herniation or trauma can result in symptom progression.

Dural dissection cyst: a more accurate term for extradural meningeal cyst

AIMS

Spinal extradural meningeal cyst (EMC) aetiology remains unclear. Based on our in-depth analysis of EMC clinical characters, we propose the alternative term 'dural dissection cyst' (DDC), which is more consistent with its aetiology and pathological manifestations.

METHODS

We examined the clinical, imaging and operative findings of four patients with spinal EMC (type I A) and analysed the aetiology and treatment of the cyst.

RESULTS

Spinal DDC was observed between T10 and L3 in our series. Patients presented with low back pain, lower extremity numbness and weakness, and segmental muscle atrophy. Small clefts were found on the inner wall of all cysts. Microscopic suture of the cleft successfully improved patient's symptoms and neurological deficits.

CONCLUSIONS

Spinal EMC (type I A) is characterized by dural dissection, so the term DDC can best reflect its aetiology. Because it is a dissection cyst, the most reasonable treatment is to suture the fistula.

Spinal extradural arachnoid cysts

OBJECTIVE: Extradural arachnoid cysts (EACs) are rare causes of spinal cord compression and cauda equina. These benign lesions appear in the literature mainly as single case reports. In this article, we present the largest series found in literature, with four new cases of spinal extradural arachnoid cysts. The characteristic imaging features, details of surgical steps and strategies to prevent postoperative kyphosis in this cystic pathology will be discussed.

Symptomatic thoracic arachnoid cyst with coexisting tick paralysis: case report and review of the literature

Tick paralysis is an uncommon phenomenon resulting from the release of a neurotoxin from the salivary glands of an engorged, gravid female tick about 5-7 days after attachment. The neurotoxin produces ascending weakness, mimicking other ascending paralytic processes. We present a case of a child presenting with weakness of the lower extremities and frequent falls who was found to have a compressive thoracic arachnoid cyst and a large distal syrinx. After surgical decompression, the patient made significant improvement in her leg strength, but quickly developed an ascending quadriparesis, followed by respiratory depression. Subsequent imaging and physical examination revealed an engorged tick embedded in her scalp. The tick was removed, and the patient made a rapid and complete clinical recovery. We present a unique case of concomitant tick paralysis and a symptomatic spinal intradural arachnoid cyst, and review the literature on tick paralysis.

What is a reasonable surgical procedure for spinal extradural arachnoid cysts: is cyst removal mandatory? Eight consecutive cases and a review of the literature

BACKGROUND

Spinal epidural arachnoid cysts (EAC) are rare and may present with myelopathy, which can be completely curable with surgery. The majority of investigators believe that the repairment of dural defect is important to treat EAC. However, the necessity of excising EACs remains controversial. The purpose of this study was to find a reasonable surgical technique for treatment of EACs after considering the clinical outcome, recurrence, and complications.

METHODS

The data from 44 operations in the literature and eight cases from our own experience were analyzed. This data included the surgical method, patient characteristics, level and size of the EAC, global assessment of the clinical outcomes, and the incidence of recurrence.

RESULTS

The recurrence rate was 2.0 % and 66.7 % in the patients who underwent repair of the dural defect and in those failed to repair of the dural defect, respectively (p = 0.007). The recurrence rate was 8.3 % and 3.6 % in patients who underwent complete EAC excision totally, and those who underwent EAC fenestration only, respectively (p = 0.590). The clinical outcome in patients with repaired dural defects was significantly better than that in patients with unrepaired dural defects (2.61 vs.1.67) (p = 0.027). The clinical outcome score was 2.42 and 2.68 in patients who underwent complete EAC excision and those who underwent EAC fenestration only, respectively (p = 0.158). The mean EAC length was 5.04 vertebral body levels (range, 2-13). Six of the 51 patients (11.7 %) had multiple EACs.

CONCLUSIONS

Total excision of EACs may have little benefit in terms of cyst recurrence and clinical outcome. The procedure for EAC resection carries a risk of complications such as kyphosis. If EAC resection is performed, we suggest that a tailored short-level laminotomy be used to allow for the repair of dural defects. Particularly in patients with small EAC, a partial hemilaminectomy with dural defect repair may be a possible method to reduce complications.

Spinal arachnoid cysts in the pediatric population: report of 31 cases and a review of the literature

OBJECT

The goal of this study was to review all cases of pediatric spinal arachnoid cysts (SACs) surgically treated at the authors' institution between 1992 and 2008 and to compare these cases to the published literature for the general population.

METHODS

The charts of all pediatric patients with SACs were reviewed for demographics, medical history, presenting symptoms, imaging findings, operative procedure(s), complications, and outcomes. Following a complete literature review, the pediatric data were compared with data from the general population and unique findings associated with pediatric patients were identified.

RESULTS

Thirty-one pediatric patients (median age 6.9 years) underwent operative intervention for SACs between 1992 and 2008 (median duration of follow-up 4.2 years). There were 17 female patients (55%) and 14 male patients (45%). Twenty-one patients (68%) presented with symptoms of radiculopathy or myelopathy. The most common presenting symptoms were pain (42%), lower-extremity weakness (39%), gait instability (32%), spasticity (19%), sensory loss (10%), and bladder dysfunction (7%). In 3 patients (10%) SACs were incidental findings. Intradural SACs were more common (18 patients, 58%) than extradural SACs (11 patients, 36%). One patient (3%) had extradural and intradural components. One patient (3%) had a purely intramedullary cyst, and 1 patient (3%) had both an intradural and intramedullary component. Of the 18 intradural SACs, 9 (50%) were located ventral to the spinal cord and 9 (50%) were dorsally situated. One dorsal intradural SAC had an intramedullary component. All extradural SACs were located dorsal to the spinal cord. Intradural SACs were primarily concentrated in the cervical and thoracic regions (67%), whereas extradural cysts were more evenly distributed between the thoracic, lumbar, and sacral regions. Of the 18 patients with intradural SACs, 13 (72%) had significant previous CNS abnormalities, compared with 3 (27%) of 11 patients with extradural SACs. There were 2 operative complications. One patient had a CSF leak treated with a lumbar drain, and the second patient had a pseudomeningocele. No patients had neurological deterioration as a result of surgical intervention. Twenty-one patients (68%) had complete remission of symptoms, 6 (19%) had improvement, 3 (10%) were stable, and 1 (3%) has worsening of symptoms with recurrence that ultimately required cystoperitoneal shunting, despite multiple failed attempts at fenestration.

CONCLUSIONS

Spinal arachnoid cysts are rare lesions in the pediatric population. Affected patients present with back pain, weakness, and/or gait instability. In children, SACs predominantly develop in the thoracic region and are more likely to occur intradurally, compared with SACs in the general population. Overall outcomes following surgical fenestration or excision of SACs are excellent, with complete remission or improvement of symptoms achieved in 87% of cases.

Spinal extradural meningeal cyst in klippel-trenaunay syndrome

A case of a symptomatic spinal extradural meningeal cyst (SEMC) in Klippel-Trenaunay syndrome (KTS) is introduced. A 38-year-old woman presented with right L2 radiculopathy. She underwent operations for varicose veins in both her lower extremities. She had port-wine nevi on her trunk and extremities. The edematous change in both legs had waxed and waned. Magnetic resonance imaging showed an 11.8×13 mm extradural meningeal cyst growing through the intervertebral foramen in L2-3. Multiple meningeal cysts were located in the dorsal aspect of the spinal cord from T3 to T10. A 5.8×6.2 mm cyst was also found in left pleural cavity. The extradural meningeal cyst was completely excised and the preoperative symptom was improved. KTS is a congenital disorder due to a mesodermal abnormality, which may predispose the dura to weakness. The SEMC may occur through the dural defect or weakened point.

Extradural giant multiloculated arachnoid cyst causing spinal cord compression in a child

BACKGROUND

Spinal extradural arachnoid cysts are rare expanding lesions in the spinal canal. Enlargement may cause progressive signs and symptoms caused by spinal cord compression. They are associated with trauma, surgery, arachnoiditis, and neural tube defects. Most nontraumatic spinal extradural arachnoid cysts are thought to be congenital.

DESIGN

Case report and literature review.

FINDINGS

A 9-year-old boy with mild paraparesis was found to have an extradural multiloculated arachnoid cyst with fibrous septa at T4-L3 levels and anterior compression and displacement of the spinal cord.

CONCLUSIONS

Definitive treatment of arachnoid cyst entails radical cyst removal and dura cleft repair. Formation of a postoperative cerebrospinal fluid fistula may require external lumbar drainage.

Kyste arachnoïdien intramédullaire symptomatique. À propos de deux cas et résumé de la littérature

OBJECTIVE

The objective of this work is to present and discuss the rare situation of curable medullary compression with favorable prognosis.

MATERIAL AND METHOD

Two cases of thoracic intramedullary arachnoid cysts are described. Clinical, paraclinical, therapeutics and outcome features are discussed with a review of the literature.

RESULTS

Two children, 4 and 8 years old, with an uneventful history were admitted for progressive spastic paraparesia. MRI demonstrated a thoracic intramedullary cystic lesion at level T3-T4 in both patients. The cyst was emptied with partial cyst wall resection via dorsomedial myelotomy. The pathology examination confirmed the diagnosis of arachnoid cyst. The initial clinical signs resolved completely in both patients.

CONCLUSION

Thought in children, intramedullary arachnoidian cyst is a potential cause of medullary compression. Direct surgery is the treatment of choice.

Multiple spinal extradural meningeal cysts presenting as acute paraplegia

✓Multiple spinal extradural meningeal cysts are rare. To the authors' knowledge, there have been only four reported cases in the world literature. The authors report a case of multiple spinal extradural meningeal cysts in a 31-year-old woman presenting with acute paraplegia. Magnetic resonance imaging of the thoracolumbar spine revealed multiple extradural cystic lesions extending from T-7 to T-8 and from T-12 to L-3. Intraoperative findings demonstrated a white, fibrous, and tense cyst filled with cerebrospinal fluid–like colorless fluid. Excision of the posterior wall of the symptomatic cyst was followed by immediate neurological improvement. The examination of the pathological specimen showed a thick duralike layer of collagen and an inner membrane of arachnoid that is often not found in these lesions. The final diagnosis was based on combined imaging, intraoperative, and histopathological findings. The authors review the literature and discuss the etiological, diagnostic, and therapeutic aspects of this lesion.

Multiple spinal extradural arachnoid cysts occurring in a child

Symptomatic multiple extradural arachnoid cysts of the spine are extremely uncommon in children and have only rarely been reported. The authors report a case of multiple extradural spinal arachnoid cysts in a 14-year-old child who presented with signs of spinal cord compression. The disease affected the thoracic spine and extended from T-5 to T-10 with an underlying defect in the dura of the spinal canal that was predisposed to the formation of cysts. The authors describe the imaging examination, surgical planning, and surgical technique, and they review the literature. They also discuss the possible mechanisms of cyst formation.

Multiple spinal extradural arachnoid cysts occurring in a child

✓Symptomatic multiple extradural arachnoid cysts of the spine are extremely uncommon in children and have only rarely been reported. The authors report a case of multiple extradural spinal arachnoid cysts in a 14-year-old child who presented with signs of spinal cord compression. The disease affected the thoracic spine and extended from T-5 to T-10 with an underlying defect in the dura of the spinal canal that was predisposed to the formation of cysts. The authors describe the imaging examination, surgical planning, and surgical technique, and they review the literature. They also discuss the possible mechanisms of cyst formation.

Dural Repair for Intraspinal Extradural Meningeal Cyst -Case Report-

A 52-year-old woman presented with an intraspinal extradural meningeal cyst in the thoracolumbar region manifesting as progressive sensory disturbance of the bilateral lower extremities. Magnetic resonance imaging and computed tomography myelography showed an extradural meningeal cyst extending from the T-12 to L-4 levels in the thoracolumbar region with a dural defect and a valve-like mechanism developed in the enlarging cyst. Operative findings revealed a dural defect that allowed communication between the extradural cyst cavity and the subarachnoid space. Surgical resection of the cyst wall and repair of the dural defect resolved the symptoms.

Utility of Preoperative Magnetic Resonance Imaging Myelography for Identifying Dural Defects in Patients with Spinal Extradural Arachnoid Cysts: Case Report

OBJECTIVE:

Preoperative magnetic resonance imaging (MRI) myelography scans demonstrated a dural defect in a 50-year-old man with an epidural arachnoid cyst who had a 29-year history of untreated weakness and numbness both lower limbs.

METHODS:

MRI scans showed a dorsal intraspinal extradural cystic lesion at the level from Th11 to L1. Although preoperative cine-MRI scans failed to display the dural defect, an MRI myelography scan showed cerebrospinal fluid in the subarachnoid space containing a cyst.

RESULTS:

The site of shunting between the subarachnoid space and the cyst was visualized as a pulsating flow void to the right of Th12. We removed the cyst wall and closed the dural defect via laminectomy.

CONCLUSION:

Because the preoperative MRI myelography scan correctly identified the existence and location of the dural defect, we conclude that MRI myelography is helpful for detecting dural defects in patients with epidural arachnoid cysts.

Expansive duraplasty for the treatment of spinal extradural arachnoid cysts

✓ The authors report the case of a 25-year-old man with a thoracolumbar extradural arachnoid cyst who underwent expansive duraplasty. Symptoms, preoperative magnetic resonance imaging features, and intraoperative findings suggested the involvement of entrapment neuropathy in the manifestation of symptoms. To the authors’ knowledge, this case represents the first evidence that expansive duraplasty can achieve complete resolution of the symptoms in a patient with a spinal extradural arachnoid cyst. The results indicate that duraplasty may be an alternative option in cases in which complete resection of the lesion is difficult and widening of the dural sac is necessary at surgery.

Ventral extradural spinal meningeal cyst causing cord compression: neurosurgical treatment

Spinal extradural meningeal cysts are typically formed by a thin fibrotic membranous capsule, macroscopically similar that of an arachnoid membrane, filled by cerebro spinal fluid and related to a nerve root or to the posterior midline. Ventral location is extremely rare and when it occurs they usually cause spinal cord herniation through the ventral dural gap. A 61 year-old man who began with a two years long history of insidious tetraparesis, spasticity and hyperreflexia in lower extremities, and flaccid atrophy of upper limbs, without sensory manifestations, is presented. Investigation through magnetic resonance imaging demonstrated an extensive spinal ventral extradural cystic collection from C6 to T11. The lesion was approached through a laminectomy and a cyst-peritoneal shunt was introduced. The cyst reduced in size significantly and the patient is asymptomatic over a 48 months follow-up. This is the first reported case of a spontaneous ventral extradural spinal meningeal cyst causing cord compression. Cyst-peritoneal shunt was effective in the treatment of the case and it should be considered in cases in which complete resection of the cyst is made more difficult or risky by the need of more aggressive surgical maneuvers.

Detection of a dural defect by cinematic magnetic resonance imaging and its selective closure as a treatment for a spinal extradural arachnoid cyst

STUDY DESIGN

We document a giant spinal extradural arachnoid cyst treated by selective closure of the dural defect. It was diagnosed using cinematic magnetic resonance imaging (cine-MRI).

OBJECTIVE

To demonstrate the effectiveness of selective closure of the dural defect as a treatment for a spinal extradural arachnoid cyst.

SUMMARY OF BACKGROUND DATA

The standard treatment for a spinal extradural arachnoid cyst is total resection of the cyst wall, if possible, and the closure of the communication site, if any, between the cyst and the subarachnoid space, after an extensive laminectomy. To our knowledge, selective closure of the dural defect through minimal laminotomy with little cyst resection has not been reported.

METHODS

A 29-year-old woman presented with right leg muscle weakness and was diagnosed with an extradural arachnoid cyst ranging from spinal regions T11 to L3 using MRI. Myelography demonstrated that the cyst communicated with the subarachnoid space. Cine-MRI showed a pulsating flow voiding on the left side of level L1, suggesting the location of the communication site. Fenestration of the T12-L1 region was performed, preserving the spinous processes and the facet joints. A small dural rent was found on the left side of level L1. This was closed using small clips.

RESULTS

MRI 12 days later demonstrated that the cyst had shrunk dramatically. It had disappeared completely by 4 months. The patient's muscle weakness improved gradually, and she was almost complaint-free 6 months after the operation.

CONCLUSIONS

Selective closure of the dural defect based on cine-MRI will be useful for treating extradural arachnoid cysts.

Effectiveness of a transforaminal surgical procedure for spinal extradural arachnoid cyst in the upper lumbar spine

Spinal extradural arachnoid cysts are relatively rare, and the pathogenesis is still unclear. Here, we report a 24-year-old woman with a Type I lesion by Nabors' classification (extradural arachnoid cyst without spinal nerve root fiber involvements), who complained of low back pain and right thigh pain, treated surgically using a transforaminal approach. Magnetic resonance imaging (MRI) and myelography showed a large extradural cystic lesion close to the L1 nerve root sleeve, accompanied by moderate L1 nerve root compression and a communication between the extradural cyst and the subarachnoid space. Resection of the cyst wall and closure of the ostium were easily performed by this approach. This procedure resulted in the relief of both low back pain and right thigh pain. Histological examination showed clusters of meningothelial cells, which was a typical feature of arachnoid cysts. Postoperative MRI demonstrated that both the cystic lesion and nerve root compression had disappeared. This transforaminal procedure proved useful for the treatment of a lesion located around a lumbar spinal nerve root.

Spinal extradural arachnoid cyst--case report

A 48-year-old male presented with progressive leg weakness. Magnetic resonance imaging and computed tomography myelography showed an extradural arachnoid cyst extending from the T-12 to L-2 levels in the thoracolumbar region. The cyst was confirmed at surgery and completely removed. This surgical intervention achieved improvement in the neurological symptoms.

Sacral meningeal cyst associated with valve-like mechanism--case report

A 58-year-old woman presented with low back pain radiating to the lower extremities. Magnetic resonance imaging revealed a cystic lesion in the sacrum compressing the nerve roots. At operation, a valve-like communication was found between the subarachnoid space and the cyst cavity in the vicinity of the sacral nerve root. The communication was obliterated with a purse-string suture and reinforced with a free muscle graft. Postoperatively, she reported improvement of the pain. Valve-like communication between the cyst cavity and subarachnoid space can cause enlargement of spinal meningeal cyst, and could also explain enlargement of sacral meningeal cyst. Surgical obliteration of the communication rather than the cyst resection is more important for sacral meningeal cyst.

Spinal arachnoid cyst with weakness in the limbs and abdominal pain

A 7-year-old male admitted with neck rigidity, severe pain in the abdomen, and progressive weakness in the lower limbs was diagnosed as having a spinal intramedullary arachnoid cyst. There was a dramatic and immediate recovery after fenestration of the cyst.