Gas-filled intradural cysts of the lumbar spine and the possible pathogenesis

Background contextThere have only been four reports of gas-filled intradural cysts, and the pathogenesis is unknown.PurposeTo document the radiologic and histopathologic features of gas-filled intradural cysts and to discuss the pathogenesis with a review of the literature.Study designCase report.MethodsA 67-year-old woman, admitted to our institute, presented with severe right thigh pain. On admission to the institute, enhanced magnetic resonance imaging, showed a cystic lesion in the spinal canal at the L2–L3 level, with an intensity suggesting the presence of gas. An enhanced region around the cyst was noted. Computed tomography after discography also revealed a water-soluble contrast filled the subarachnoid space and area around the cyst, but not inside.ResultsThe cyst was surgically resected. One of the nerve roots was firmly adherent to the gas-filled cyst. The cyst wall comprised fibrous tissue, including small granulations and herniated disc material.ConclusionGas-filled intradural cysts are rare. The pathogenesis appears to involve gas in a degenerated intervertebral disc, and spontaneous absorption of herniated disc material.     

Gas-filled intradural cyst with migration into the nerve root of the cauda equina

Only 4 cases of gas-filled intradural cysts of the spine have been reported previously. All cysts were due to intradural herniation of a gas-containing disc. The authors report 2 additional patients with gas-filled intradural cysts that migrated into the nerve root of the cauda equina. After surgical treatment their severe leg pain completely resolved.     

Spontaneous resorption of intradural lumbar disc fragments.

BACKGROUND CONTEXT: Intradural disc herniation is relatively rare complication of the spinal degenerative process that occurs most frequently in the lumbar part of the spine. Both myelographic and magnetic resonance features of this entity have been described, and the mechanism of intradural herniation has already been proposed and generally accepted. In this article, we present a case of spontaneous resorption of an intradural, fragmented intervertebral disc. Spontaneous resorption of intradural disc fragments has not been previously reported. PURPOSE: To discuss a possible mechanism of spontaneous resorption of the subdural disc fragments. STUDY DESIGN: Case report and literature review. METHODS: Radiological follow-up of a 46-year-old man with the intradural herniation of disc fragments. CONCLUSION: The reaction generated by the meninges might lead to the complete resorption of intrathecally localized disc fragments.     

A gas filled intradural cyst associated with disc degeneration

A case of a lumbar intradural, extramedullary gas filled cyst is described. This was associated with degenerative disc disease and presented with radicular signs and symptoms. The radiological differential diagnosis of such a mass includes infection and tumours. The association of intradural gas with degenerative disc disease is previously reported. This case further illustrates the association of degenerative disc disease with an intradural gas filled cyst and provides an interesting radiological differential diagnosis for an extramedullary intradural mass.     

Intradural Disc Herniation in the Setting of Congenital Lumbar Spinal Stenosis

IntroductionAccounting for an estimated 1.10-1.76% of all lumbar herniations, lumbar intradural disc herniation (IDH) occurs primarily in males during the fourth to fifth decades of life. While not validated, congenital lumbar spinal stenosis (CLSS) is implicated as one precipitating factor for IDH.Case reportWe report 28-year-old Hispanic female with CLSS, severe obesity, and degenerative disk disease, with a history of minimally invasive surgical (MIS) decompression for a large paracentral L4-5 disc herniation at 25. After three years, the patient developed sudden burning dysesthesias in the L4-5 dermatomes bilaterally and temporary leg weakness. Lumbar magnetic resonance imaging exhibited severe L4-5 spinal stenosis, and the patient underwent repeat MIS decompression, which again provided her with adequate symptom resolution. However, 20 days postoperatively she developed cauda equina syndrome with anal dysfunction, and bilateral leg and foot weakness. Upon open surgical exploration we discovered a tense L4-5 dural protrusion. After a dorsal durotomy, a large IDH with a ventral dural tear was identified. Subsequent to adequate debulking of the IDH, the ventral tear was repaired, and an expansile duraplasty was performed. Overall, the patient's bladder and bowel function, pain, hypoesthesia, and motor strength all improved. Two weeks after surgery she presented with a lumbar pseudomeningocele that was managed conservatively.ConclusionThis report not only highlights an atypical presentation of IDH and is the first case of CLSS linked with IDH, lending support to the hypothesis that CLSS can lead to IDH, but also provides a comprehensive review of IDHs.     

Thoracolumbar intradural extramedullary bronchiogenic cyst

Summary Intradural extramedullary bronchiogenic cysts are rare findings. All five reported cases were located cervically or upper thoracically. To our knowledge, we describe the first case of an intraspinal bronchiogenic cyst in a thoracolumbar location.We present the case of a 41-year-old patient with a known spina bifida occulta who suffered from a continuous, sharp, and therapy-refractory pain in the left leg. Magnetic resonance imaging of the thoracic and lumbar vertebra revealed an intradural extramedullar mass at T12 to L1 level. After laminectomy T-12 through L-1/L-2 and longitudinal opening of the dura mater, the cystic mass was shown to be attached to the conus medullaris and the cauda equina, and therefore could be removed only partially. Histopathological examination revealed the diagnosis of bronchiogenic cyst. We therefore conclude that intradural extramedullary bronchiogenic cysts may appear also at thoracolumbar levels. Surgical resection can be achieved with good outcome.     

Transradicular lumbar disc herniation: An extreme variant of intraradicular disc herniation

Intradural or intraradicular lumbar disc herniation (IDH) is a relatively rare condition often diagnosed intraoperatively. We encountered an extreme variant of IDH - a transradicular herniation as the disc material extruded through the lumbar nerve root through a split essentially transecting the nerve root. While failure to recognize intradural and intraradicular disc herniation can lead to failed back surgery, the variant described in the present case could lead to iatrogenic injury and complication if not recognized. A unique case of transradicular lumbar disc herniation in a 25-year-old patient is presented with the depiction of intraoperative images supplementing the text.     

Spontaneous resorption in recurrent intradural lumbar disc herniation. Case report

The authors report a case of spontaneous resorption of intradural disc material in a patient with recurrent intradural lumbar disc herniation and review magnetic resonance (MR) imaging and histopathological findings. Intradural lumbar disc herniation is rare, and most patients with this condition require surgical intervention due to severe leg pain and vesicorectal disturbance. In the present case, however, the recurrent intradural herniated mass had completely disappeared by 9 months after onset. Histological examination of intradural herniated disc tissue demonstrated infiltrated macrophages and angiogenesis within the herniated tissue, and Gd-enhanced MR images showed rim enhancement not only at the initial presentation, but also at recurrence. The authors conclude that when rim enhancement is present on Gd-enhanced MR images, there is a possibility of spontaneous resorption even though the herniated mass may be located within the intradural space. Moreover, when radiculopathy is controllable and cauda equina syndrome is absent, conservative therapy can be selected.     

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.     

Lumbar intradural extramedullary bronchiogenic cyst

The pathological findings of an intradural and extramedullary cyst at the L1 level of the spinal canal are described in a 28-year-old male who presented with chronic lumbago and progressive weakness and numbness in both lower limbs. Histopathological examination revealed the diagnosis of bronchiogenic cyst. Bronchiogenic cysts in the spinal canal are uncommon, and cysts at the L1 level are extremely rare. Their pathogenesis is still poorly understood. They are thought to be a malformation arising from a split notochordal syndrome. We conclude that intradural extramedullary bronchiogenic cysts may appear also at lumbar levels. Surgical resection can be achieved with good outcome.     

Cervical intradural disc herniation

STUDY DESIGN: A case report of anterior en bloc resected cervical intradural disc herniation and a review of the literature. OBJECTIVE: To discuss the pathogenesis of cervical intradural disc herniation. SUMMARY OF BACKGROUND DATA: Including this study case, only 17 cases of cervical intradural disc herniation have been reported. There have been few detailed reports concerning the pathogenesis of cervical intradural disc herniation. METHODS: A cervical intradural disc herniation at C6-C7, with localized hypertrophy and segmentally ossified posterior longitudinal ligament, is reported in a 45-year-old man who had Brown-Sequard syndrome diagnosed on neurologic examination. Neuroradiologic, operative, and histologic findings, particularly the pathology of the anterior en bloc resected posterior vertebral portion of C6 and C7, were evaluated for discussion of the pathogenesis. RESULTS: Adhesion of dura mater and hypertrophic posterior longitudinal ligament was observed around a perforated portion of the herniated disc, and histologic study showed irregularity in fiber alignment accompanied by scattered inflammatory cell infiltration and hypertrophy in the posterior longitudinal ligament. The cervical intradural disc herniation was removed successfully and followed by C5-Th1 anterior interbody fusion with fibular strut graft. Neurologic recovery was complete except for minor residual sensory disturbance in the leg 7 years after the surgery. CONCLUSIONS: Cervical intradural disc herniation is an extremely rare condition. The pathogenesis remains obscure. Only 16 cases have been reported in the literature, and there has been little discussion concerning the local pathology of the herniated portion. The pathogenesis of the disease in the patient reported here was considered to be the adhesion and fragility of dura mater and posterior longitudinal ligament. This was caused by hypertrophy, with chronic inflammation and ossification of the posterior longitudinal ligament sustaining chronic mechanical irritation to the dura mater, leading to perforation of the herniated disc by an accidental force.     

Variant of a lumbar disc cyst in a 13-year-old girl: a case report

A disc cyst is a rare entity with a clinical presentation that closely mimics an intervertebral disc herniation. Disc cysts are ventrally located, intraspinal, extradural cystic lesions that communicate with the parent intervertebral disc through a ruptured annulus. We present the clinical features, magnetic resonance imaging, intra-operative and histopathological findings of a variant of a lumbar intervertebral disc cyst in a 13-year-old girl who presented with a 6-month history of unilateral radiculopathy following an injury. Magnetic resonance imaging revealed a large posterocentral, fluid-filled cyst occupying the L5-S1 interspace and bulging into the spinal canal. The cyst was confined within an intact bulging annulus fibrosis and extended directly from the parent disc. The cyst was surgically decompressed, resulting in complete symptomatic relief.     

Intraosseous ganglion cyst within the L4 lamina causing spinal stenosis

Background context

There are rare reports of intraosseous ganglion cysts in the cervical spine. However, to our knowledge, there are no previous reports of these cysts occurring in the lumbar spine.

Purpose

To report a case of symptomatic lumbar spinal stenosis caused by an intraosseous ganglion cyst of the L4 lamina that communicated with the spinal canal.

Study design

Case report.

Methods

An 86-year-old woman was referred to our spine service for a 2-year history of anterior thigh and leg pain. Magnetic resonance imaging revealed a benign-appearing intraosseous cyst in the left L4 lamina communicating with a posterior epidural cyst at L4–L5 causing marked spinal stenosis. The patient was treated successfully with a laminectomy and resection.

Results

The patient underwent partial laminectomies of L4 and L5 preserving the interspinous ligaments between L5–S1 and L3–L4. The cyst was removed en bloc without violation of the cyst wall. Histopathologic examination revealed focal myxoid changes without a cellular lining of the cyst wall, confirming the diagnosis of intraosseous ganglion cyst.

Conclusions

This is the first report to describe an intraosseous ganglion cyst occurring in the lumbar spine. Although spinal stenosis is commonly a result of degenerative joint or disc disease, it occasionally may result from more obscure causes. This case illustrates a patient with an intraosseous ganglion cyst within the spinal lamina resulting in spinal stenosis, treated successfully with a laminectomy and resection.     

Pathogenesis of the discal cysts communicating with an adjacent herniated disc. Histological and ultrastructual studies of two cases

Discal cyst of the lumbar spine is a very rare cause of back pain and sciatica. We report two cases of discal cysts communicating with an adjacent herniated disc. From CT and MRI findings, they were diagnosed as having a discal cyst in the epidural space, which compressed the nerve root. After an adequate surgical field was obtained with a microscope and a Casper retractor, the discal cyst could be excised and satisfactory decompression of the adjacent nerve root was obtained. From histological and electron microscopic study, the presence of residual herniated tissues was confirmed in the cyst wall. Macrophages played an important role in the absorption of herniated tissue and the formation of the discal cyst. Hemorrhage in the cyst wall will make the serous hemorrhagic fluid-filled cystic structure in the absorbed spaces of the prolapsed disc. In this study, we confirmed that the discal cyst could have developed from the absorption process of a disc herniation.     

Cervical anterior intradural arachnoid cyst in a child

Intradural arachnoid cysts involving the spine are uncommon and especially rare in an anterior cervical location. In the literature, among 15 patients, 8 were in the paediatric age group and in 3 patients the cyst was localised to the full length of the cervical spinal canal. Although they occur secondary to trauma, haemorrhage, surgery or inflammation, most of them are known to be idiopathic or congenital. Although the disease shows a dramatic neurological course, early diagnosis and treatment could provide good results. We report a 2(1/2) year-old boy with progressive tetraparesis with a huge anterior intradural arachnoid cyst located from the cervico-medullary junction to the C7 level. In the paediatric age group, cervical anterior intradural arachnoid cyst is an unusual cause of quadriparesis. The rarity of this condition and the relevance of MRI in the accurate and early diagnosis is discussed here. A 2(1/2) year-old boy with a large intradural arachnoid cyst extending from the cervico-medullary junction to C7 situated anteriorly is reported here; diagnosis and treatment modalities are discussed.     

Posterior and anterior epidural and intradural migration of the sequestered intervertebral disc: Three cases and review of the literature

Context: Dorsal migration of the sequestered lumbar intervertebral disc is an unusual and underrecognized pattern of lumbar disc herniation associated with pain and neurological deficit.Findings: Three patients presented with lower limb- and low back pain. MR imaging showed intracanalicular mass lesions with compression of the spinal cord and allowed precise localization of lesions in the extradural or intradural space. Diagnosis was straightforward for the patients with the posterior and anterior epidural disc fragments, whereas various differential diagnostic considerations were entertained for the patient with the intradural mass lesion. All patients underwent surgical removal of the sequestered disc fragments, and recovered full motosensory function. Surgical repair of the dura mater due to CSF leak was required for the patient with intradural disc herniation.Conclusion/clinical relevance: Posterior and anterior epidural, and intradural disc migration may manifest with clinical symptoms indistinguishable from those associated with non-sequestered lumbar disc hernias. Missed, migrated disc fragments can be implicated as a cause of low back pain, radiculopathy or cauda equina syndrome, especially in the absence of visible disc herniation. A high index of suspicion needs to be maintained in those cases with unexplained and persistent symptoms and/or no obvious disc herniation on MR images.     

Spinal cord herniation associated with an intradural spinal arachnoid cyst diagnosed by magnetic resonance imaging

Two rare cases of spinal cord herniation associated with intradural spinal arachnoid cyst are reported. A preoperative magnetic resonance imaging scan demonstrated the presence of spinal cord herniation, identified as a protrusion continuous with the spinal cord. Surgery upon the intradural spinal arachnoid cyst improved progressive neurological dysfunction. The authors postulate that spinal cord herniation occurred for the following reason: The pressure of the intradural arachnoid cyst on the dorsal aspect of the spinal cord caused thinning of the dura, leading to a tear and, thus, the development of an extradural arachnoid cyst. Along with the enlargement of intradural arachnoid cyst, the spinal cord herniated through the tear in the dura into the extradural arachnoid cyst.     

Intraradicular disc herniations in the lumbar spine and a new classification of intradural disc herniations

STUDY DESIGN: A case report of intraradicular disc herniation. Intraradicular disc herniation is a special type of intradural disc herniations. In this report, we present the tenth case of intraradicular lumbar disc herniation and suggest a new classification for intradural disc herniations. CASE REPORT: A 32-year-old male was admitted to hospital having experienced pain in the lower back and right leg for 1 month prior to admission. Neurological examination revealed weakness of the extensor hallucis longus, positive Laségue's sign, decreased ankle reflex in his right lower extremity, and bilateral paravertebral muscle spasm. Magnetic resonance imaging (MRI) revealed a disc herniation with a posterolateral extruded fragment on the right at the level of the L5-S1 space. He underwent L5 laminectomy. During the operation, the right S1 root was found to be swollen and immobile. A longitudinal incision was made in the dura of the right S1 root and an intradural free disc fragment was removed, and the S1 root was relieved. The patient was free of pain postoperatively. CONCLUSION: We suggest a new classification for intradural disc herniations with this unusual case presentation and review the literature for pathogenesis, clinical picture, diagnosis and treatment.     

Extensive intradural arachnoid cyst of the lumbar spinal canal: case report

BACKGROUND: Spinal intradural arachnoid cysts are rare outpouchings of arachnoid lining occurring mainly in the thoracic and cervical regions. MRI is considered the diagnostic procedure of choice; however, some arachnoid cysts have been reported to elude diagnosis by MRI due to the similar signal intensity of the cyst and the subarachnoid space. CASE DESCRIPTION: We present a case of a 41-year-old woman with an intradural arachnoid cyst of the lumbar spinal canal. Diagnostic studies demonstrated a herniated L4-5 disk, which led to two operations. Despite intractable pain postoperatively, the MRI failed to reveal further focal compression of the nerve root. A myelogram suggested compression of the thecal sac by a dorsal mass lesion. The patient underwent a midline durotomy that revealed two large arachnoid cysts with the nerve roots beneath them pushed ventrally and to the right. Removal of the arachnoid layer resulted in complete fenestration of the cyst and allowed the nerve roots to freely float in the spinal fluid. CONCLUSION: In retrospect, the abnormality could be appreciated on multiple prior scans performed at another institution, demonstrating that in the patient with low back pain, degenerative disc disease is not the only diagnosis to consider.