Spinal intradural arachnoid cyst

Systematic Review of Surgical Management of Spinal Intradural Arachnoid Cysts

OBJECTIVE

Spinal intradural arachnoid cysts (SIACs) are rare pathological lesions that can arise via outpouchings of the arachnoid layer in the spinal canal that can result in neurological deficits. We performed a systematic literature review regarding the current surgical techniques used in the management of SIACs and discussed the prevailing hypotheses surrounding the etiology of SIACs.

METHODS

A systematic search of the literature was performed in December 2020 using EMBASE and MEDLINE for reports regarding the surgical management of SIACs. Data were collected regarding the demographics of the patients, classification system used, presence or absence of syrinxes, preoperative imaging modality, surgical approach and extent of resection, and postoperative outcomes and follow-up.

RESULTS

Our search yielded 19 reports for inclusion in the present study. The 19 studies included a total of 414 cases, with an overall male/female ratio of 0.93:1. The most common site for the SIACs was the thoracic spinal cord at 77.5%. The symptoms were very similar across the 19 studies. Of the 19 studies, 15 had used resection to manage the SIACs, 10 had used fenestration or marsupialization, and 4 had used cystoarachnoid or cystoperitoneal shunts.

CONCLUSIONS

SIACs are rare and debilitating spinal pathological lesions, with the etiology of primary SIACs still not fully elucidated. Multiple surgical approaches have been effective, with the optimal operative strategy largely dependent on the individual patient and cyst factors on a case-by-case basis.

Cord Splitting Access to Ventral Intradural Cysts of Cervicothoracic Junction and Thoracic Spine

OBJECTIVE

Surgical treatment of ventrally located intradural cysts is difficult and controversial. Laminectomy with division of the denticulate ligaments and gentle cord mobilization remains the standard approach but risks further neurologic deterioration secondary to cord manipulation. Our purpose is to evaluate the safety and effectiveness of a midline cord-splitting approach as an alternative for treating ventral thoracic intradural cysts.

METHODS

We describe 2 patients who were treated for ventral intradural cysts causing progressive and severe myelopathy. Under general anesthesia and continuous neurophysiologic monitoring, laminectomy, durotomy, and cord splitting through a midline approach gave direct access to both lesions. Cyst drainage was supplemented by a cystopleural shunt in 1 case.

RESULTS

Cyst collapse and cord reexpansion were documented in both patients with a magnetic resonance imaging scan 1 week after surgery. In both cases there was a significant neurologic improvement, which was maintained 2 years postoperatively. Intraoperative monitoring recorded no loss of somatosensory or motor potentials during surgery. Follow-up magnetic resonance imaging scans 2 years postoperatively showed no evidence of cyst recurrence, and both patients remained neurologically improved and stable.

CONCLUSIONS

We have been able to drain 2 ventral intradural cysts using a cord-splitting technique. This has allowed safe access to purely ventrally located lesions, which were inaccessible dorsally or dorsolaterally. By using this method we have been able to avoid a more invasive ventral transthoracic approach necessitating vertebrectomy and reconstruction and risking serious complications.

[Clinical presentation of a dorsal epidural arachnoid cyst after an epidural anesthesia]

BACKGROUND

Arachnoid cysts are dural diverticula with liquid content similar to cerebrospinal fluid, with 1% occurring in the spinal cord. They locate mainly in the dorsal region of the thoracic spine, and are unusual causes of spinal cord compression.

CLINICAL CASE

The case is presented of a previously healthy 15-year-old boy, with a 20-month history of spastic paraparesis that started apparently after epidural block for ankle osteosynthesis. There was decreased sensitivity and strength of the pelvic limbs and gradually presented with anaesthesia from T12 to L4 dermatomes, L5 and S1 bilateral hypoaesthesia and 4+/5 bilateral strength, in the L2 root and 2+/5 in L3, L4, L5, S1, hyperreflexia, Babinski and clonus, but with no alteration in the sacral reflexes. In the magnetic resonance it was diagnosed as an extradural arachnoid cyst from T6 to T9. The patient underwent a T6 to T10 laminotomy, cyst resection, dural defect suture, and laminoplasty. One year after surgery, the patient had recovered sensitivity, improvement of muscle strength up to 4+/5 in L2 to S1, and normal reflexes.

CONCLUSIONS

After the anaesthetic procedure, increased pressure and volume changes within the cyst could cause compression of the spinal cord, leading to symptoms. Despite being a long-term compression, the patient showed noticeable improvement.

Animated respiratory movement of a spinal intradural arachnoid cyst visualized by intraoperative ultrasonography

This study aims to describe the animated respiratory movement of a spinal intradural arachnoid cyst visualized by intraoperative ultrasonography. A 69-year-old man with a spinal arachnoid cyst of the thoracic spine presented with gait disturbance. Magnetic resonance images showed a mild anterior displacement and flattening of the spinal cord at T4-T5. We performed ultrasonography before incision of the dura during the operation and observed the movement of the cyst consisting of not only pulsation in accordance with the cardiac cycle but also rhythmic expansion and contraction in accordance with the respiratory cycle. In the inspiratory phase, the cyst gradually expanded and pulsated in accordance with the cardiac cycle. In the expiratory phase, the cyst gradually contracted with the same pulsation. After resection of the cyst, the patient's neurological improvements were excellent. To our knowledge, this is the first report of animated respiratory movement of a spinal arachnoid cyst visualized by intraoperative ultrasonography. Although cine magnetic resonance imaging can detect spinal intradural arachnoid cysts preoperatively, intraoperative ultrasonography is useful for close analysis of their movement and pathology. Considering the dynamic compression mechanism revealed in this study, we think that an early operation should be performed for such cysts.

Scalloping Sacral Arachnoid Cyst as a Cause of Perianal Pain- A Case Report

Introduction:

Scalloping sacral arachnoid cyst though a rare condition, should be suspected in cases of persistent perianal pain without any obvious urological or anorectal pathology. Such difficult cases justify ordering an M.R.I of spine as plain X-Rays and clinical examination may come out to be inconclusive. X-ray in later stages may show changes corresponding to scalloping of bone due pressure effect of cyst on surrounding tissue. Diagnosis may further be confirmed by doing contrast MRI which differentiates arachnoid cyst from other intradural and extradural pathologies. Though anatomically spinal arachnoid cysts are just an out pouching from the spinal meningeal sac or nerve root sheath they may be extradural or intradural in their location, communicating to main C.S.F column through their pedicle or an ostium leading to continuous enlargement in size.

Case Report:

A 32 year old female was admitted under our spine unit with 1.5 year history of chronic pain, swelling and reduced sensation in perianal region. On examination she had tenderness and hypoesthesia over lower sacral region. The pain was continuous, dull aching in nature, not related to activity, localized over lower sacrum and perianal area. The neurological examination of her both lower limbs were unremarkable. Anal tone and anal reflex were normal. No sign of inflammation or tenderness was found over coccyx. Since the X-rays were inconclusive an MRI scan was done which showed a cystic lesion in the sacral area extending from S2 to S4 region with mechanical scalloping effect on the surrounding bone. The lesion had same intensity as C.S.F in both T1 &T2 weighted images. The treatment was done by way of surgical decompression with complete excision of cyst and obliteration of space by a posterior midline approach. Presently the patient is 1 year post operative and no sign of recurrence is there.

Conclusion:

Sacral arachnoid cysts should be considered as a differential diagnosis of perianal pain. Large symptomatic sacral cysts should be treated early with complete removal of the cyst including the cyst wall, to reduce the chances of recurrence. Complete decompression of the cyst cavity should be aimed at, but careful dissection of neural element is of highest importance.

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.

Symptomatic isolated lumbar interdural arachnoid cyst

A 72-year-old man presented with an extremely rare case of symptomatic isolated lumbosacral interdural arachnoid cyst manifesting as pain and weakness in the right buttock and lower extremity that had aggravated for 2 weeks. Although the surgical strategy for the interdural cyst was not complicated, the origination of the cyst was not clearly understood. Surgery found an isolated membrane of the cyst inside double-layered dura without communication with the intact arachnoid membrane. Cerebrospinal fluid with hemorrhage accumulated within the interdural cyst indicated recent bleeding into the cyst. Our experience suggests that this cyst was congenital based on the surgical results and imaging studies.

Surgical treatment of spinal intradural arachnoid cysts using endoscopy

Object

Spinal intradural arachnoid cysts are a rare cause of spinal cord compression. Since 2000, the authors have treated patients using 2- or 3-level hemilaminectomy or laminectomy followed by partial cyst wall resection as well as endoscopic inspection and fenestration of the cyst wall. They evaluated the usefulness and reliability of endoscopic treatment for this clinical entity based on long-term follow-up results.

Methods

Between 1997 and 2003, 11 patients (3 males and 8 females) with spinal intradural arachnoid cysts were treated, and the authors conducted a retrospective review of these cases. Before 2000, 5 patients were surgically treated without the use of endoscopic techniques. During that time, more than 4 levels of hemilaminectomy were performed to expose and remove cyst walls that extended longitudinally over the spinal axis. Beginning in 2000, endoscopy was used in all 6 cases. Up to 3 levels of hemilaminectomy or 2 levels of laminectomy were performed, and the cyst wall was resected through the bone window. An endoscope was inserted into the cyst cavity and moved in the cranial and caudal direction to fenestrate the cyst wall, resulting in communication of the cyst cavity with the subarachnoid space.

Results

Postoperatively, the neurological symptoms of all patients improved. During long-term follow-up (mean 114.8 months), none of the patients treated with or without endoscopy experienced recurrent cyst formation.

Conclusions

Endoscopic techniques allow neurosurgeons to treat spinal intradural arachnoid cysts less invasively than with standard surgical approaches. Although the number of cases reviewed in this report is small, the data suggest that the use of endoscopy can be an important option in the surgical treatment of spinal arachnoid cysts.

Diffuse arachnoid ossification and multiple arachnoid cysts presenting with progressive thoracic myelopathy

An ossified arachnoid membrane combined with cystic formation is rarely reported as a cause of spinal cord compression. We report the case of a 60-year-old man who presented with diffuse ossification of the arachnoid membrane (arachnoid ossification) and multiple cystic changes (arachnoid cyst) at the thoracic and lumbar spine. The lesions were surgically removed and progressive deterioration was prevented, although no marked improvement of neurological symptoms was attained.

Syringomyelia associated with a spinal arachnoid cyst

While syringomyelia is not a rare spinal disorder, syringomyelia associated with a spinal arachnoid cyst is very unusual. Here, we report a 62-year-old man who suffered from gait disturbance and numbness of bilateral lower extremities. Spinal magnetic resonance imaging (MRI) showed the presence of a spinal arachnoid cyst between the 7th cervical and 3rd thoracic vertebral segment and syringomyelia extending between the 6th cervical and 1st thoracic vertebral segment. The cyst had compressed the spinal cord anteriorly. Syringomyelia usually results from lesions that partially obstruct cerebrospinal fluid flow. Therefore, we concluded that the spinal arachnoid cyst was causing the syringomyelia. After simple excision of the arachnoid cyst, the symptoms were relieved. A follow-up MRI demonstrated that the syringomyelia had significantly decreased in size after removal of the arachnoid cyst. This report presents an unusual case of gait disturbance caused by syringomyelia associated with a spinal arachnoid cyst.

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.

Rapid expansion of a ventral arachnoid cyst after syringo-subarachnoid shunting in the thoracic spinal cord: case report

BACKGROUND

Intradural spinal arachnoid cysts have rarely been reported in association with intramedullary cysts. These associated lesions most commonly occur in the thoracic spine.

CASE DESCRIPTION

We reported an unusual balance of cerebrospinal fluid dynamics between an initially occult arachnoid cyst and syringomyelia. The arachnoid cyst was not allowed to express itself until the syrinx was decompressed with a syringo-subarachnoid shunt.

CONCLUSION

Only one other report in the literature described a similar case; however, our case is the first to be confirmed by intraoperative ultrasound.

Spinal intradural juxtamedullary cysts in the adult: surgical management and outcome

OBJECTIVE

Intradural nonneoplastic cysts compressing the spinal cord are rare lesions. We retrospectively analyzed a series of patients harboring this entity with regard to clinical and radiological features, surgical management, and follow-up results.

METHODS

In a retrospective study, we reviewed the medical charts, radiological investigations, and follow-up data of 11 women and 10 men (mean age, 43.6 yr) with intradural juxtamedullary spinal cysts, which were consecutively treated microsurgically at our institutions between January 1995 and January 2003. All lesions were approached via a laminectomy, hemilaminectomy, or laminoplasty at the corresponding vertebral levels and histopathologically verified. The patients were routinely scheduled for clinical follow-up 2 and 6 months after surgery. Baseline postoperative magnetic resonance imaging (MRI) was ordered 6 months after surgery. Thereafter, follow-up was performed at 1-year intervals, with neurological examination and MRI.

RESULTS

According to presenting symptomatology, two main patient groups could be differentiated: one group with a myelopathic syndrome (10 patients) and another group with a predominant radicular pain syndrome (8 patients). Histopathological examination revealed 16 arachnoid cysts, 4 neuroepithelial cysts, and 1 cervical nerve root cyst. Most arachnoid cysts (12 cases) were located on the dorsal aspect of the thoracic spinal cord. The mean craniocaudal extension of these cysts was 3.7 vertebral levels, and complete resection was performed. In four patients, the arachnoid cyst was situated ventral to the spinal cord and involved up to 17 vertebral levels. These patients had a history of major spinal trauma, and the cyst was generously fenestrated at its greatest circumference as depicted on preoperative MRI scans. The four neuroepithelial cysts and the cervical nerve root cyst were located on the ventral or ventrolateral aspect of the spinal cord, and their maximum sagittal extension was two spinal vertebral levels. Symptoms in all but two patients demonstrated major improvement; in particular, radiating pain disappeared immediately after surgery. There was no cyst recurrence on MRI after a mean follow-up period of 3.2 years.

CONCLUSION

Intradural cysts should be considered in the differential diagnosis of lesions causing myelopathy and/or a radicular pain syndrome. Microsurgical resection or generous fenestration in cysts with large craniocaudal extensions effectively ameliorated patients' symptomatology. A description of the first documented case of a surgically treated intradural cervical nerve root cyst is provided.

Spinal arachnoid cysts associated with syringomyelia: report of two cases and a review of the literature

We describe two cases of spinal arachnoid cyst associated with syringomyelia and report the clinical results after surgical treatment using excision of the cyst without a shunt operation for the syringomyelia. Case 1 is a 73-year-old woman who presented with a spastic gait and numbness of her bilateral lower extremities. Magnetic resonance imaging (MRI) showed the presence of a spinal arachnoid cyst extending from T3 to T8 and syringomyelia from T8 to T10. The cyst had compressed the spinal cord anteriorly. We excised the cyst without applying a shunt tube for the syringomyelia. Case 2 is a 68-year-old woman who presented with gait disturbance and numbness of her left lower extremity. MRI indicated that the spinal cord had been compressed anteriorly by a spinal arachnoid cyst extending from T10 to T11. Syringomyelia existed just caudal to the cyst at T11. In our surgical treatment, we excised only the cyst. In both cases, neurologic examination after the operation showed amelioration of the condition. Postoperative MRI indicated that the spinal cord had moved to the center, its original position, and the syringomyelia had decreased in size. Conclusively, spinal arachnoid cyst associated with syringomyelia can be treated by simple excision of the cyst without shunting the syrinx if the decompression effect resulting from removal of the cyst is sufficient.

Symptomatic spinal arachnoid cysts: report of two cases with review of the literature

STUDY DESIGN

Two unusual cases of intradural extramedullary noncommunicating arachnoid cysts are presented, with a review of literature.

OBJECTIVE

To assess surgical excision results in the reversal of symptoms and neurologic deficits.

SUMMARY OF BACKGROUND DATA

Most patients harboring arachnoid cysts are asymptomatic. Noncommunicating intradural extramedullary arachnoid cysts are more rare than communicating intradural extramedullary cysts. Noncommunicating intradural extramedullary arachnoid cysts are a very rare cause of spinal cord compression. Rarely, these cysts can present with bizarre symptoms, such as angina.

MATERIALS AND METHODS

The first case, a 75-year-old woman, presented with progressive paraparesis. The second case, a 40-year-old man, presented with signs and symptoms of angina, with mild spasticity in the lower limbs. In both cases, magnetic resonance imaging revealed compression of the spinal cord as the etiology of presentation. The first patient is the second oldest patient in the literature with an idiopathic spinal arachnoid cyst. The second case has an unusual presentation that has not previously been reported in the literature.

RESULTS

Both cases underwent surgical excision of the arachnoid cyst, with resolution of symptoms and reversal of neurologic deficit.

CONCLUSIONS

Our experience indicates that complete recovery from an arachnoid cyst is possible after surgical excision, even when symptoms are present for a long duration, even in the elderly.

A recurrent intradural cervical neurenteric cyst operated on using an anterior approach: a case report

The neurenteric cyst is an uncommon congenital lesion. In most reported cases, it has been operated on via a posterior approach using a laminectomy, despite the fact that the cyst is usually located ventral to the spinal cord. Reports have shown that early postoperative results have been good with the posterior approach, but very few studies of the long-term postoperative recurrence of neurenteric cysts have been conducted. Here, we report on a case of recurrent neurenteric cyst that was operated on using an anterior approach.A 42-year-old woman presented with a cervical neurenteric cyst that had recurred eight years after its partial removal via a posterior approach. The patient complained of pain on the lateral side of her upper arms, and an magnetic resonance imaging showed that the recurrent cyst was located ventral to the spinal cord and compressed the cord dorsally at the C4-6 level. The patient was operated on via an anterior approach using a vertebrotomy at the lower half of C5 and the upper half of C6. The cyst was attached to the spinal cord firmly and was subtotally removed, with the thickest portion adhering to the cord not being removed. The caudal end of the cyst was observed with the assistance of a rigid endoscope.A neurenteric cyst may recur after partial removal, and the patient's condition may deteriorate during postoperative follow-up. The anterior surgical approach provides good visualization and facilitates safe removal of the lesion.

Intramedullary arachnoid cyst. Case report

The authors present an unusual case of intramedullary arachnoid cyst diagnosed in a patient after the lesion was resected. A wide decompressive surgery was performed and the lesion removed. Histopathological findings were consistent with the diagnosis of arachnoid cyst. Postoperatively the patient exhibited marked improvement in neurological status. To the best of the authors' knowledge, there is no case report of intramedullary arachnoid cyst reported in the literature. With the advent of newer neuroimaging modalities such as magnetic resonance imaging the number of cases of intramedullary arachnoid cysts encountered in the future may increase.

Intradural arachnoid cyst associated with thoracic spinal compression fracture: 7-year follow up after surgery

STUDY DESIGN

A case report with long-term follow after a surgical procedure.

OBJECTIVES

To describe a case of intradural arachnoid cyst secondary to a compression fracture in the thoracic spine and to report long-term results after surgical treatment with hemilaminectomy.

SETTING

Osaka, Japan.

METHODS

A 68-year-old man who had a traumatic intradural arachnoid cyst following an adjacent compression fracture of T5 underwent surgery. Intraoperatively, after recognition of intradural arachnoid cyst with an echogram following hemilaminectomy, the dural sac was incised and the arachnoid cyst was resected under microscopic observation.

RESULTS

At 7 years after the operation, the low intensity within the vertebral body of the compression fracture had resolved and the spinal cord remained in its normal shape and position. No progression of kyphotic deformity was detected.

CONCLUSION

A compression fracture of the thoracic spine can be associated with an intradural arachnoid cyst. Microscopic resection via hemilaminectomy for the cyst showed a good result in a 7-year follow up.

Aracnoidite constritiva causada por pantopaque resultando em siringomielia e paraparesia: relato de caso

Relatamos caso de aracnoidite constritiva torácica, verificada 10 anos após o uso de pantopaque, que foi utilizado em mielografia no diagnóstico de cisto aracnóideo.

Dorsal arachnoid web with spinal cord compression: variant of an arachnoid cyst? Report of two cases

Spinal arachnoid cysts are diverticula of the subarachnoid space that may compress the spinal cord; these lesions are most commonly found in the thoracic spine. Two patients who presented with thoracic myelopathy were noted on magnetic resonance imaging to have focal indentation of the dorsal thoracic cord, with syringomyelia inferior to the site of compression. Both patients were found at operation to have discrete arachnoid "webs" tenaciously attached to the dura mater and pia mater. These webs were not true arachnoid cysts, yet they blocked the flow of cerebrospinal fluid (CSF) and caused focal compression of the spinal cord. The mass effect appeared to be the result of a pressure gradient created by the obstruction of CSF flow in the dorsal aspect of the subarachnoid space. Both patients responded well to resection of the arachnoid web. Arachnoid webs appear to be rare variants of arachnoid cysts and should be suspected in patients with focal compression of the thoracic spinal cord.

Anterior thoracic intradural arachnoid cysts

Anterior thoracic intradural arachnoid cysts (ATIACs) are a rare cause of spinal cord and nerve root compression, for which different treatment strategies have been proposed. Although ATIAC represents a well-known clinical entity, the choice of surgical method has not been uniform, and no study has been specifically designed to compare the results of the different treatment options adopted.

The authors report the case of a 40-year old man with a 1-year history of dorsal pain, weakness in the lower extremities, gait disturbance, and mild sexual and urinary dysfunction. On neurological examination spastic paraparesis, lower-extremity hypertonia, and hypesthesia below T-2 were demonstrated. Magnetic resonance imaging revealed the presence of an ATIAC at the T-2 level. The patient underwent complete microsurgical removal of the cyst.

The authors conducted a Medline search of the relevant literature from 1966 to 1998 and also obtained data on other cases in which patients underwent surgical treatment of ATIAC. The literature search yielded five such cases. Treatment strategies were complete excision and fenestration followed by placement of a shunt. In addition, one case was characterized by intraoperative cyst rupture during retraction of the spinal cord.

Correct preoperative workup coupled with microneurosurgical technique allow for successful removal of the lesion and excellent outcome. Based on the literature review and the results in our case, the complete excision of ATIAC is associated with an excellent outcome, which is different from results achieved using other surgical strategies.

Cine magnetic resonance imaging of spinal intradural arachnoid cysts

OBJECTIVE

The diagnostic value of cine magnetic resonance imaging (CMRI) that visualizes fluid and tissue movement was evaluated in patients with spinal intradural arachnoid cysts, a rare but increasingly detected cause of spinal cord dysfunction.

METHODS

Four patients with thoracic spinal intradural arachnoid cysts were investigated with conventional T1- and T2-weighted and cardiac-gated CMRI. Four normal volunteers also underwent CMRI for comparison.

RESULTS

Sagittal T1- and T2-weighted imaging showed lesions as an abnormal widening of the posterior spinal subarachnoid space, but mixed high- and low-signal intensities on T2-weighted imaging suggested cystic lesions. CMRI, using 16 to 20 sagittal gradient echo images during the cardiac cycle of normal volunteers, indicated synchronous signal changes along the subarachnoid space, suggesting a smooth cerebrospinal fluid flow. CMRI of patients detected that the caudal or cranial direction of the high-signal propagation suddenly reversed at some locations (as if rebounding) in an asynchronous fashion along the lesion (asynchronous rebound phenomenon), which was well demonstrated by the closed-loop video mode. Cystectomy revealed that the cysts consisted of multiple lobules and that the asynchronous rebound phenomenon corresponded with some boundaries of cyst lobules. CMRI also visualized dynamic spinal cord compression by the cyst.

CONCLUSION

CMRI can demonstrate abnormal fluid flow and spinal cord compression caused by a spinal intradural arachnoid cyst.

Symptomatic spinal intradural arachnoid cyst development after lumbar myelography. Case report and review of the literature

STUDY DESIGN

This case report describes the unique occurrence of acquired intradural spinal arachnoid cyst after lumbar puncture, which was proven radiographically and surgically.

OBJECTIVES

To review and explore complications of lumbar puncture in the context of subsequent cyst development and to review the incidence, presentation, pathogenesis, and management of spinal intradural arachnoid cysts.

SUMMARY OF BACKGROUND DATA

The etiology of the spinal intradural arachnoid cyst remains obscure; some such cysts are ascribed anecdotally to previous trauma or arachnoiditis, whereas the majority are idiopathic and assumed by many authors to be congenital.

METHODS

A 20-Year-old woman with back and leg pain underwent lumbar myelography that yielded normal results with no evidence of arachnoid cyst at that time. Within 5 months, clinical symptoms of cauda equina compression and an S1 radiculopathy developed. Subsequent myelography and magnetic resonance imaging revealed a lumbar spinal arachnoid cyst. There was no history of intervening trauma or arachnoiditis. The lumbar puncture was thought to be the cause of the arachnoid cyst.

RESULTS

A laminectomy was performed with complete excision of the arachnoid cyst. The patient had an unremarkable postoperative course with excellent relief of her symptoms.

CONCLUSIONS

This case provides supporting evidence for the traumatic etiology of spinal intradural arachnoid cyst. The development of an intradural spinal arachnoid cyst should be included as a possible complication of lumbar puncture.

Multiple communicating intradural arachnoid cysts: usefulness of myelography and myelo-computed tomography using both lumbar and cervical punctures. Case report

We report a case of multiple communicating intradural cystic lesions. Magnetic resonance imaging did not demonstrate the lesions. Neuroradiological diagnosis of the intradural arachnoid cysts was made from myelography and myelo-computed tomography using both lumbar and cervical punctures. These procedures give us useful information about flow dynamics in the spinal subarachnoid space.

Traumatic interdural arachnoid cyst in the upper cervical spine. Case report

The case of an interdural arachnoid cyst of traumatic origin at the C3-5 level in an 18-year-old man was admitted to our hospital with a 1-year history of progressive weakness in left limbs and numbness below the clavicles is reported. He had had a C-2 fracture at the age of 9 years without definite neurological deficits. Magnetic resonance imaging revealed a cystic lesion in the C3-5 level. Laminectomy was performed, and an interdural cyst was found. Histological examination revealed fibrous thickening of the arachnoid membrane. A cyst located in the interdural space of upper cervical spine is extremely rare.

Cine-mode magnetic resonance imaging of a thoracic intradural arachnoid cyst: case report

We report the appearance of a thoracic intradural arachnoid cyst on cine-mode magnetic resonance imaging (MRI). Based on the operative findings, cine-mode MRI was more sensitive for identifying the intradural location of arachnoid cysts than was conventional MRI. The value of cine-mode MRI in diagnosing this rare entity is discussed.

An unusual spinal intradural arachnoid cyst

Spinal intradural arachnoid cysts are seen most frequently in the thoracic region, particularly near the midline posteriorly. A thoracic intradural arachnoid cyst in this typical location is reported, with the additional unusual finding of herniation of the spinal cord through an anterior defect in the dura matter. The MRI findings are described.

Craniospinal intradural arachnoid cyst

A patient with an uncommonly situated congenital intradural arachnoid cyst is reported. The cyst extended from the cervical spinal canal into the posterior cranial fossa and was posterolateral to the spinal cord. The patient's initial complaint was urinary hesitancy. The location of the cyst is unique and the presenting complaint rare.

Spinal arachnoid cysts in the pediatric age group: an association with neural tube defects

Between 1979 and 1991, spinal arachnoid cysts were found in 11 patients aged 19 months to 18 years (mean age 5 1/2 years). Of the 11 patients, six had a myelomeningocele and one diastematomyelia. The presenting symptoms included radicular pain (one patient), progressive weakness (three), increasing scoliosis (one), worsening spasticity (three), and recurrent urinary tract infections and progressive constipation (one). Two patients showed no symptoms from the spinal arachnoid cyst. The distribution of lesions was as follows: cervicomedullary (one patient), cervical (one), cervicothoracic (two), thoracic (four), lumbar (two), and sacral (one). Four of the 11 arachnoid cysts (all intradural) were located anterior to the spinal cord, three of which were in children with a myelomeningocele. Only two of the cysts were extradural; both were found in the lumbosacral region, and one was associated with diastematomyelia. Eight patients were treated with fenestration and/or resection of the cyst wall. Three patients with anterior cysts were treated with shunts, a cyst-to-pleural space shunt in two and a cyst-to-subarachnoid space shunt in one. All of the patients either improved or exhibited an arrest in the progression of their symptoms. Spinal arachnoid cysts are a treatable cause of progressive neurological deficits and, in this series, were frequently found in patients with neural tube defects.

Intradural extramedullary cysts of the spinal canal: clinical presentation, radiographic diagnosis, and surgical management

Fourteen patients with intradural extramedullary cysts of the spinal canal are described. Histological classification included 11 arachnoid, 2 epithelial, and 1 ependymal cyst. There were 9 thoracic, 3 cervical, and 2 lumbar cysts. The most common clinical presentation was a slowly progressive myelopathy. Twelve patients (85%) had objective neurological findings at the time of diagnosis. Radiographic diagnosis was made by a combination of myelography, computed tomographic scan with myelography, and magnetic resonance imaging. Complete surgical resection was accomplished for 8 dorsal cysts, and 6 ventral cysts were widely fenestrated into the subarachnoid space. Overall results were considered excellent or good in 9 patients, fair in 3, and poor in 2. There was one recurrence, which required a second operation. We conclude that the majority of intradural spinal cysts can be successfully managed surgically with a favorable clinical outcome.

A variant of the syndrome of spinal arachnoid cysts with multiple congenital defects

We report an apparently unique case of multiple spinal intradural arachnoid cysts in association with distichiasis, late onset lower limb lymphoedema, and previously unrecognized features of associated bilateral megaureters, Arnold Chiari malformation with hydrocephalus and syringomyelia. The literature on this unusual group of congenital malformations is reviewed.

Thoracic intradural arachnoid cyst: possible pitfalls with myelo-CT and MR

A thoracic intradural arachnoid cyst presenting as an intradural extramedullary mass highly suggestive of psammoma on myelogram and myelo-CT is reported in a 34-year-old female. High densities of the cyst were related to collection of contrast media within the cyst. However MR examination of the thoracic spinal cord including sagittal T1 (without and with contrast) and T2 studies failed to demonstrate the mass. Lack of MR changes were related on one hand to the small size of the cyst and to the absence of mass effect on the spinal cord, and on the other hand to a CSF-like signal of the contents of the cyst. Only combination of myelography, myelo-CT and MR allows precise diagnosis of small intradural arachnoid cyst; however MR is the method of choice for evaluation of large intradural subarachnoid cysts.

Intradural spinal arachnoid cyst. Case report

An intradural spinal arachnoid cyst presenting with spinal cord compression is discussed. This case illustrates the value of magnetic resonance imaging in the diagnosis and follow-up of intradural spinal arachnoid cysts.

Spinal cord compression due to intradural extramedullary aspergilloma and cyst: a case report

A case of thoracic spinal cord compression caused by intradural extramedullary cyst associated with aspergilloma is presented. The specific diagnosis was extremely difficult and required specialized tissue studies. Clinical suspicion of fungal infection, surgical intervention for spinal cord decompression, and tissue biopsy and relentless diagnostic laboratory studies are particular features of this case.

Spinal meningeal malformations in children (without meningoceles or meningomyeloceles)

Multiple meningeal malformations are described: anterior or lateral meningoceles, extradural meningeal cysts, and intradural arachnoid cysts. All diverticulae appear to be extensions of the subarachnoid space, producing symptoms early or later. It is impossible to unify all these lesions because they cause multiple pathological conditions, depending upon the anatomical form or level, other systemic malformations, spinal abnormalities, or associated familial diseases. Surgical treatment requires complete evaluation of each anatomical aspect before procedure.

Intradural arachnoid cysts of the spinal canal associated with intramedullary cysts

Five patients had intradural arachnoid cysts of the thoracic spinal canal associated with syringomyelia or posttraumatic intramedullary spinal cord cysts. Three cases were diagnosed 6 to 18 years after spinal surgery and two 14 to 17 years after spinal cord trauma. In each case, delayed progression of symptoms led to the identification of the lesions. The diagnosis was assisted by the use of myelography and delayed computerized tomography scanning in two cases and by magnetic resonance imaging in all five. In each case, the arachnoid cyst appeared to compress the spinal cord or nerve roots; in three cases, the syrinx cavities appeared to exert a significant mass effect. In the two trauma-related cases, the intramedullary cysts were small and may have represented areas of cystic myelomalacia. In four cases, intraoperative real-time ultrasonography helped to localize the arachnoid and intramedullary cavities. All five patients were treated by fenestration of the arachnoid cyst; additional peritoneal shunting of the cyst was performed in one case and of the intramedullary cavity in three. In one patient, the two lesions appeared to have a balancing effect; after drainage of the arachnoid cyst, the syrinx cavity expanded and had to be treated separately. The neurological deficits were reduced in four patients and stabilized in one. Intradural arachnoid cysts and intramedullary cysts may occur together as a late complication of spinal surgery or spinal cord trauma, and either or both lesions may cause delayed neurological deterioration.

Long-term results of surgically treated congenital intradural spinal arachnoid cysts

The authors report long-term results in 17 patients with surgically treated congenital intradural spinal arachnoid cysts. Comparison between the immediate and long-term results demonstrates that surgical removal of the cyst allowed a significant neurological improvement in all cases, but clinical worsening of various degrees was observed later. The authors attempt to explain the results in terms of mechanical and vascular factors.

Percutaneous insertion of the spinal end of a cysto-peritoneal shunt as definitive treatment to relieve cord compression from a spinal arachnoid cyst

A case of myelopathy with both intradural and extradural spinal arachnoid cysts is reported treated by cysto-peritoneal shunt, the spinal end of which was inserted percutaneously under fluoroscopic control. The site of drainage was determined by findings at computed myelography. The case illustrates the value of the latter in demonstrating the pathological bio-mechanics producing myelopathy in this condition.

Spinal intradural arachnoid cysts

Based on the study of 8 cases of spinal intradural arachnoid cysts, the authors underline that the diagnosis is sometimes difficult because of the limitations of the paraclinical examination. They discuss aetiopathological problems.

Spinal intramedullary pseudocyst. Case report

The authors describe a case of a spinal intramedullary pseudocyst at T-1 that did not communicate with the surrounding spaces. The cystic wall was composed of dense connective tissue without epithelial or neoplastic cells. The patient's condition improved dramatically after surgical removal of the cyst. The literature on spinal intramedullary cystic lesions is reviewed and the etiology of pseudocysts is discussed. This case is believed to be the first in which a pseudocyst has been demonstrated within the spinal cord.