Surgical treatment of idiopathic transdural spinal cord herniation: a new technique to untether the spinal cord

Summary Idiopathic transdural spinal cord herniation is a rare but treatable cause of thoracic myelopathy caused by herniation of the spinal cord through a defect in the dura. The diagnosis is frequently missed or delayed, but the latest imaging techniques can document spinal cord herniation through a dural defect. Surgical treatment, consisting of reducing the herniation by closing the dural defect or widening the aperture to prevent spinal cord compression, is rather successful. We describe a new technique to untether the spinal cord by wrapping a dura graft around the myelum to prevent recurrent transdural herniation. Two patients and a review of the literature are discussed. We conclude that high-resolution T2 magnetic resonance imaging is the best imaging modality to detect the entity, and wrapping the myelum is an effective surgical technique to untether the spinal cord.     

Idiopathic spinal cord herniation associated with intervertebral disc extrusion: a case report and review of the literature

STUDY DESIGN: A case of idiopathic spinal cord herniation is reported, and the literature is reviewed. OBJECTIVE: To report a case of thoracic spinal cord herniation with a ventral dural defect, probably caused by thoracic disc extrusion. SUMMARY OF BACKGROUND DATA: Recently, reports of spinal cord herniation have been increasing. This increase can be attributed to the development of magnetic resonance imaging and increased awareness of this entity. However, the cause of the ventral dural defect remains unknown. METHODS: A 54-year-old woman had experienced Brown-Séquard syndrome for 2 years. Magnetic resonance imaging demonstrated an S-shaped anterior kinking of the spinal cord, with dilation of the dorsal subarachnoid space. RESULTS: After incision of the dural sac and gentle retraction of the spinal cord, a dural defect was recognized into which the spinal cord had herniated. An extruded disc was visualized through the defect at T3-T4. The ventral dural defect and the dorsal incision of the dural sac were repaired with a fascial graft from the thigh. CONCLUSIONS: Intraoperative findings suggest that the thoracic disc herniation in the current case was the probable cause of the ventral dural defect. Surgical reconstruction using double fascial graft under careful spinal cord monitoring resulted in a satisfactory neurologic recovery.     

Resolution of Chiari malformation after repair of a congenital thoracic meningocele: case report and literature review

OBJECTIVE AND IMPORTANCE: Many theories have been proposed regarding potential causative factors for Chiari malformations. An unusual case is described in which regression of a congenital Chiari malformation was observed after repair of a thoracic meningocele without direct surgical intervention to decompress the craniocervical junction. This supports the importance of an in utero craniospinal pressure gradient as a potential cause for congenital, but reversible, cerebellar herniation. CLINICAL PRESENTATION: A newborn baby was observed to have a thoracic meningocele. Magnetic resonance imaging scan revealed a concomitant Chiari malformation. No neurological deficits were present at initial examination. INTERVENTION: The patient underwent surgical closure of the thoracic meningocele and untethering of the spinal cord at the site of the dural defect. A postoperative magnetic resonance imaging scan obtained 3 months after the operation revealed complete resolution of the cerebellar herniation. CONCLUSION: The resolution of the Chiari malformation in this child may have resulted from restoration of normal cerebrospinal fluid flow and elimination of the meningocele-related cerebrospinal fluid pressure gradient between the intracranial and intraspinal compartments.     

Idiopathic spinal cord herniation associated with calcified thoracic disc extrusion--case report

A 48-year-old man presented with idiopathic spinal cord herniation associated with calcified thoracic disc extrusion at the T7-8 intervertebral level, manifesting as Brown-Sequard syndrome at the thoracic level persisting for 20 years. Preoperative magnetic resonance imaging and computed tomography myelography revealed ventral displacement of the spinal cord and extrusion of a calcified disc at the T7-8 intervertebral level. At surgery, the spinal cord herniation at this level was released from the dura mater and carefully returned to the dural sac. An extruded calcified thoracic disc was found just below the dural defect at the same level. The development of idiopathic spinal cord herniation is associated closely with a defect in the ventral dura mater of unknown etiology. In our case, the etiology of the ventral dural defect was probably associated with the calcified thoracic disc extrusion.     

Idiopathic spinal cord herniation: diagnostic, surgical, and follow-up data obtained in five cases

Idiopathic spinal cord herniation (ISCH) is a rare, although increasingly recognized, cause of myelopathy. It is the result of an anterior dural defect in the thoracic spine through which the spinal cord herniates. Surgical restoration of the herniated cord to its normal position is usually followed by significant improvement in patients' clinical status. Differing surgical techniques have been used to manage the dural defect. In this report the authors discuss the cases of five patients (four women and one man) with ISCH treated during a 13-year period. Clinical and imaging findings in each patient are reported. Two different surgical techniques were used to treat this condition: dural defect enlargement in two cases and dural patch secured with stitches in three. The intra- and postoperative findings are discussed in relation to the two surgical techniques. Based on the results and complications in these five cases, the authors now believe that ISCH should be treated, when feasible, by using a dural patch to close the dural defect at the site of the herniation.     

Dorsal thoracic spinal cord herniation: report of an unusual case and review of the literature

Background context

Spinal cord herniation is a rare but well-documented condition that has been associated with tethering through the dural defect. Both spinal cord herniation and cord tethering result in progressive myelopathy that can be improved or stabilized with surgical intervention. Most cases of herniation are caused by dural defects in the ventral or ventrolateral thoracic spine, rarely occurring through the dorsal dura. This is the first reported case of a spontaneous dorsal herniation.

Purpose

To describe a unique case of thoracic tethered cord resulting from a dorsal dural defect through which there is spinal cord herniation.

Study design

A case report and review of the literature.

Methods

A 55-year-old man presented with progressive low back pain, paresthesias, and weakness in his left lower extremity that was exacerbated by walking. Imaging revealed a dorsal dural defect with tethering and herniation of the spinal cord at T7.

Results

The patient underwent a T6–T7 laminoplasty to release the tethered cord and repair the dural defect. At 1-year follow-up, the patient noted improvement in strength and back spasticity.

Conclusions

Spinal cord herniation through a dural defect is an uncommon but important cause of symptomatic tethered cord in adults. Surgical intervention can significantly alter the course and prevent further disability.     

Idiopathic Spinal Cord Herniation: Case Report and Review of the Literature

Background: Idiopathic spinal cord herniation (ISCH) is a rare cause of progressive myelopathy frequently present in Brown-Séquard syndrome. Preoperative diagnosis can be made with magnetic resonance imaging (MRI). Many surgical techniques have been applied by various authors and are usually reversible by surgical treatment.

Methods: Case report and review of the literature.

Findings: A 45-year-old woman with Brown-Sequard syndrome underwent thoracic MRI, which revealed transdural spinal cord herniation at T8 vertebral body level. During surgery the spinal cord was reduced and the ventral dural defect was restorated primarily and reinforced with a thin layer of subdermal fat. The dural defect was then closed with interrupted stitches.

Results: Although neurologic status improved postoperatively, postsurgical MRI demonstrated swelling and abnormal T2-signal intensity in the reduced spinal cord. Review of the English language literature revealed 100 ISCH cases.

Conclusions: ISCH is a rare clinical entity that should be considered in differential diagnosis of Brown-Séquard syndrome, especially among women in their fifth decade of life. Outcome for patients who initially had Brown-Séquard syndrome was significantly better than for patients who presented with spastic paralysis. Although progression of neurologic deficits can be very slow, reduction of the spinal cord and repair of the defect are crucial in stopping or reversing the deterioration.     

Transdural herniation of the thoracic spinal cord: untethering via a posterolateral transpedicular approach. Report of three cases

Anterior spinal cord herniation is a well-documented condition in which the thoracic cord becomes tethered within a defect in the anterior dura mater. Typical procedures have involved a posterior approach with direct manipulation of the thoracic cord to expose and blindly release its point of tethering. The authors report three cases in which a novel approach for the treatment of anterior thoracic cord herniation was performed, cord manipulation and traction are minimized, and direct dural repair of the defect is performed.     

Idiopathic spinal cord herniation: a new theory of pathogenesis

BACKGROUND: Idiopathic spinal cord herniation is a rare entity that has been described more frequently over the past few years. Its pathophysiology remains obscure, however. METHODS: We report a case of spinal cord herniation and review the literature extensively. In view of our review, we try to determine the clinical features of the condition and the diagnostic measures used, with emphasis on the role of magnetic resonance (MR) phase-contrast CSF study. The factors affecting the outcome of the condition are also studied including time and type of presentation, as well as the surgical procedure performed. The pathophysiological mechanisms behind spontaneous herniation are discussed, and a new hypothesis is proposed. RESULTS: Idiopathic spinal cord herniation occurs in the middle-aged adult, with a preponderance of patients being female. Brown-Séquard syndrome is the most common clinical presentation and usually progresses to spastic paraparesis. MRI typically shows a ventral kink in the thoracic cord, with MR phase-contrast imaging proving an important addition to exclude an arachnoid cyst. Better outcomes were noted in the patients treated earlier, and in those with no spasticity. Widening the dural defect seems to afford better results compared to grafting of the defect. The prognosis is favorable after correction, though a vertebral body herniation variant may be associated with worse outcome. In view of the chronology of events and imaging studies in our patient, we hypothesize that herniation occurs as an acquired phenomenon where an inflammatory process results in adherence between the spinal cord and the dura, with erosion, formation of a dural defect, and then later herniation occurring with cerebral spinal fluid (CSF) pulsations. CONCLUSIONS: Idiopathic herniation of the spinal cord should be recognized and treated early to reach a favorable outcome. It seems to be an acquired condition likely caused by an inflammatory event, the nature of which is to be determined.     

Spontaneous thoracic spinal cord herniation--case report.

A 54-year-old female presented with spontaneous thoracic spinal cord herniation manifesting as chronic progressive motor weakness in both legs. Spastic paraparesis (4/5) and pathological reflexes such as ankle clonus were noted. She also had mild bladder dysfunction but no bowel dysfunction. She had no sensory disturbance, including tactile and pinprick sense. Magnetic resonance (MR) imaging revealed that the atrophic spinal cord was displaced into the ventral extradural space at the T4-5 intervertebral level with markedly dilated dorsal subarachnoid space. Computed tomography obtained after myelography showed no evidence of intradural spinal arachnoid cyst. She underwent surgical repair of the spinal cord herniation via laminectomy, and spinal cord herniation through the ventral dural defect was confirmed. Postoperative MR imaging revealed improvement of the spinal cord herniation, but her symptoms were not improved. Spontaneous spinal cord herniation is a rare cause of chronic myelopathy, occurring in the upper and mid-thoracic levels, and the spinal cord is usually herniated into the ventral extradural space. Early differential diagnosis from intradural spinal arachnoid cysts is important for a satisfactory outcome.     

Idiopathic spinal cord herniation: case report and review of the literature

OBJECTIVE AND IMPORTANCE: Idiopathic spinal cord herniation (ISCH) is a rare condition, reported in only 25 patients thus far, in which the thoracic cord is prolapsed through an anterior dural defect. It typically presents in middle age as either Brown-Sequard syndrome or spastic paraparesis. CLINICAL PRESENTATION: A 55-year-old woman initially presented at the age of 41 years with Brown-Sequard syndrome at the T8 disc space level on the left side. Investigations, including primitive magnetic resonance imaging, were deemed negative at that time. After a stepwise deterioration over 14 years, she presented again with spastic paraparesis and double incontinence, in addition to her previous spinothalamic dysfunction. Magnetic resonance imaging at this stage suggested either ISCH or a dorsal arachnoid cyst. INTERVENTION: Through a T7-T8 laminectomy, a left-of-midline ISCH was identified and easily reduced by gentle cord traction. No dorsal arachnoid cyst was identified. The anterior dural defect was repaired with a XenoDerm patch (LifeCell Corp., Woodlands, TX). After surgery, there was improved motor and sphincter function. However, there was continued sensory disturbance. CONCLUSION: ISCH is rare cause of thoracic cord dysfunction. Despite prolonged diagnostic delay, significant clinical improvement may be obtained with ISCH reduction and anterior dural repair.     

Spinal cord herniation: a misdiagnosed and treatable cause of thoracic myelopathy

This study is a case report and review of the literature. Spinal cord herniation is a rare, although increasingly recognized, cause of spinal cord dysfunction. It is due to an anterior dural defect, through which the spinal cord herniates. The purpose of this article is to report the authors’ experience and to provide insight on clinical presentation and radiological signs to make the reader aware of this entity and then to prevent misdiagnosis. The authors conducted a retrospective review of patients who underwent surgery for spinal cord herniation at their institution between 2000 and 2008. Three patients were treated (all women) and the interval between the onset of symptoms and surgery ranged from 24 to 48 months. All patients had progressive signs of thoracic myelopathy, and two of them were initially misdiagnosed. In all cases, the herniation was reduced and the defect repaired using different methods. The results and complications of our cases were compared with that of the reported literature. According to the results in these cases and the review of the literature, the authors believe that spinal cord herniation should be treated by using a dural patch to close the dural defect and to prevent retethering of the spinal cord.     

Surgical technique for idiopathic spinal cord herniation: the Hammock method. Technical note

Idiopathic spinal cord herniation is a rare disease, and surgical treatment is recommended for patients with motor deficits or progressive neurological symptoms. Surgery is performed to release and reposition the tethered spinal cord. In terms of repositioning and prevention of reherniation, various procedures have been proposed; enlargement of the ventral dural defect, primary closure of the defect with sutures, and insertion of a ventral patch for duraplasty. We treated 3 patients with idiopathic spinal cord herniation, using a ventral patch for duraplasty with an expanded polytetrafluoroethylene pericardial membrane (the Hammock method), and all 3 cases had good clinical outcome. The specific important technical aspects are described and illustrated. If this procedure is performed meticulously under the microscope by following the specific techniques, the Hammock method is safer and more effective for prevention of reherniation than simple enlargement of the dural defect.     

Idiopathic spinal cord herniation which extended remarkably up- and downward from dural defect: case report

A case of idiopathic spinal cord herniation which extended remarkably up- and downward from a dural defect is described. A 53-year-old woman presented with numbness and pain of the right lower limb. Magnetic resonance (MR) imaging revealed ventral displacement of the spinal cord and dilation of the dorsal subarachnoid space at T4-5. CT Myelography showed ventral deviation of the spinal cord at the T4/5 level. A laminectomy of T3-T5 was performed, and the herniated spinal cord was untethered and wrapped by Goretex membrane. Postoperative MR image revealed normal location of the spinal cord. Among many cases of spinal cord herniations, this one is considered to be a rare case of idiopathic spinal cord herniation which showed marked protrusion up- and downward from a dural defect.     

Case of idiopathic thoracic spinal cord herniation with a chronic history: a case report and review of the literature

Idiopathic spinal cord herniation is a rare disease that presents with slowly progressive myelopathy. This article describes the clinical findings of a patient with a chronic history. A 68-year-old woman initially presented at the age of 32 years with left leg weakness. After slowly progressive neurological deterioration over 34 years, she became completely paraplegic. At the age of 66 years, magnetic resonance imaging resulted in a diagnosis of idiopathic spinal cord herniation at the T6/7 level. Surgery was performed to reduce aching of the lower extremities. The spinal cord was released from the dural defect through a T5–T8 laminectomy. The dural defect was enlarged by resecting its periphery to prevent reherniation of the spinal cord. After the surgery, pain in the lower extremities resolved and her motor function slightly improved. Although operative treatment is naturally recommended at the early stage of this disease, our case suggests that some symptoms can be resolved by surgical treatment despite prolonged, severe preoperative symptoms.     

Idiopathic spinal cord herniation associated with a large erosive bone defect: a case report and review of the literature

We report a case of idiopathic spinal cord herniation associated with a large bone defect. MRI and computed tomographic myelography revealed ventral deviation of the spinal cord and erosion of the vertebral body at T6-T7. Microscopic surgery revealed a dural defect. The etiology of this condition has not been clarified. In most previously reported cases, the peak portion of the herniation was around the intervertebral disc space. In addition, in our patient, it was hard to think that the intervertebral disc has become depressed due to the pressure exerted by the spinal cord. We considered that a certain condition of the intervertebral disc, such as herniation, was one of the causes of the dural defect, and cerebrospinal fluid pulsation pushed the spinal cord toward that portion, causing herniation.     

Thoracic transdural spinal cord herniation at a level caudal to prior discectomy

To outline a scenario of acquired transdural spinal cord herniation not previously described. The authors report their experience with a patient found to harbor a thoracic transdural spinal cord herniation at the disk space immediately caudal to a prior discectomy. Documentation of the radiographic progression of this patient’s spinal cord herniation is presented, spanning the course of 13 years. The patient underwent intradural repair of his dural defect via a lateral extracavitary approach. The herniated spinal cord was successfully reduced. The patient had modest improvement in his symptoms at 2-year follow-up. To the best of the authors’ knowledge, this case represents the first reported case documenting this anomaly at a level adjacent to that of a previous surgery within the thoracic spine.     

Idiopathic spinal cord herniation: report of three cases and review of the literature

STUDY DESIGN: Three case reports and a literature review are presented. OBJECTIVE: To describe characteristic clinical and radiographic findings of idiopathic spinal cord herniation. SUMMARY OF BACKGROUND DATA: Idiopathic spinal cord herniation is a rare disease, with only 26 cases reported before the current study. METHODS: Three cases of idiopathic spinal cord herniation are reported, and previous reports on this subject are reviewed. RESULTS: The responsible regions were in the thoracic spine from T2 to T7. Symptoms were mainly unilateral muscle atrophy in the lower extremity and sensory disturbance below the thoracic level. These symptoms had been progressing gradually. Magnetic resonance imaging demonstrated a unique feature: The spinal cord shifted anteriorly in a few segments. Computed tomographic myelogram showed another distinctive picture: There was no subarachnoid space anterior to the spinal cord. CONCLUSIONS: Because idiopathic spinal cord herniation is out of the concept of "compression myelopathy," this condition may be a pitfall in the diagnosis. Idiopathic spinal cord herniation should be recognized as one of the treatable causes for thoracic myelopathy.     

Postoperative spinal cord herniation with pseudomeningocele in the cervical spine: a case report

Background context

Postoperative spinal cord herniation with pseudomeningocele is a rare disease, with only five cases reported before the present study.

Purpose

To describe the clinical features and radiologic findings of postoperative spinal cord herniation with pseudomeningocele.

Study design

Case report.

Methods

A case of a 51-year-old man who suffered from postoperative spinal cord herniation with pseudomeningocele was reported, and previous reports on this subject are reviewed.

Results

He had undergone excision of a spinal cord tumor in the cervical spine 10 years previously. He had progressive paraparesis and urinary disturbance 10 years later. The Computed Tomography Multi Planner Reconstruction myelogram showed dilation of the ventral subarachnoid space with left deviation of the spinal cord into the pseudomeningocele at C7. On observation at surgery, the spinal cord appeared displaced dorsally and herniated through the defect of the dorsal dura mater. The spinal cord was tightly adhesive around the dural defect. We released the adhesion of the spinal cord and the dural defect under the spinal cord, and the dural defect was repaired using an artificial dura mater.

Conclusions

The release of adhesion around dural defect and repair of dural defect under spinal cord monitoring resulted in a satisfactory neurologic recovery. Surgical repair of the dural defect with a dural substitute was necessary.     

Spontaneous spinal cord herniation

Spontaneous spinal cord herniation is a rare and under recognized condition. The commonest presentation is a Brown-sequard syndrome. It most commonly occurs in the thoracic region through an anterolateral dural defect, and the pathophysiology is ill understood. We present a case of spontaneous spinal cord herniation along with a review of literature.