Focal adhesive arachnoiditis of the spinal cord: Imaging diagnosis and surgical resolution

Chiari Type I Revision Decompressive Surgery Indications and Operative Technique: Experience in a Large Adult Cohort

BACKGROUND

Chiari malformation is characterized by inferior displacement of the cerebellar tonsils through the foramen magnum, frequently resulting in strain related headaches, and motor/sensory dysfunction. Chiari decompression technique varies significantly, possibly contributing to frequent revisions. We reviewed revision Chiari decompressions at our institution to determine the primary indications for revision and outcomes after revision.

METHODS

We retrospectively reviewed patients who underwent revision of Chiari decompression at our institution from 2005 to 2020. Demographics, indications for revision surgery, operative techniques, imaging findings, and preoperative/postoperative symptoms were collected. χ2 test was performed to determine statistical significance using a P < 0.05. Independent predictors of operative outcomes were identified.

RESULTS

A total of 46 patients (91% females, mean age 38.8 years) were included for analysis. The median time to revision surgery was 69.1 months (range 0-364 months) with headache (n = 37, 80%) being the most commonly recurring symptom. Large craniectomy (n = 28, 61%) was the most frequent indication for revision surgery. Thirty-two (70%) patients underwent cranioplasty, 20 (43%) required duraplasty, 15 (33%) required arachnoid dissection, and 15 (33%) required tonsillar reduction during revision surgery. Postrevision follow-up (at 8.9 ± 5.2 months average, range 1-18 months), revealed an average reduction in all Chiari-related symptoms relative to symptoms before the revision.

CONCLUSIONS

The most common indication for revision Chiari decompression was a large craniectomy resulting in cerebellar ptosis. We found that tonsillar reduction paired with modest craniectomy achieved near-complete resolution of symptoms with minimal complications. For patients with recurrent or persistent sequelae of Chiari malformation after decompression, revision may reduce symptom severity.

Delta Cord as a Radiological Localization Sign of Postoperative Adhesive Arachnoiditis: A Case Report and Literature Review

Postoperative adhesive arachnoiditis is an inflammatory response of the spinal leptomeninges that occurs after surgery and results in scar formation in the avascular nature of the arachnoid layer. Clinical manifestations of postoperative adhesive arachnoiditis include pain, sensory deficits, motor dysfunction, reflex abnormalities, and bladder or bowel impairment. In magnetic resonance imaging scans, signs of postoperative adhesive arachnoiditis can vary; however, some indicators can assist surgeons in locating the lesion accurately and, thus, in planning effective surgical interventions. This paper reports the case of a 37-year-old man with postoperative adhesive arachnoiditis after two surgeries for Chiari I malformation. This case illustrates the progressive development of the "delta cord sign", which refers to the formation of a thick arachnoid band causing the spinal cord to adopt a triangular shape in the axial view. This phenomenon is accompanied by the sequential occurrence of syringomyelia. During intraoperative examination, we identified the presence of the delta cord sign, which had been formed by an arachnoid scar that tethered the dorsal spinal cord to the dura. This discovery enabled us to precisely pinpoint the location of the arachnoid scar and thus provided us with guidance that enabled us to avoid unnecessary exploration of unaffected structures during the procedure. Other localization signs were also reviewed.

Spinal Adhesive Arachnoiditis: A Literature Review

Adhesive arachnoiditis (AA) is a rare inflammatory and scar-forming disease with several etiologies that may lead to incapacitating sequelae if not managed early. Nevertheless, as the onset of symptoms varies from days to years, the etiology is not often discovered. The disease is characterized by adhesions disrupting the cerebrospinal fluid flow and causing encapsulation and atrophy of the nerve root. Therefore, a range of clinical features may be present, including urinary, gastroenterology, dermatologic, and neurologic. In terms of diagnosis, magnetic resonance imaging is the gold standard showing pseudocysts with adherent and narrow nerve roots toward the center of the dural sac or peripherally cluster and narrow nerve roots with empty thecal sac. Despite its sensitivity and specificity, the imaging findings are not often associated with clinical manifestations, requiring treatment being based on anamneses and clinical findings. Nowadays, AA can be managed with pharmacological and non-pharmacological treatment, although none provides a completely satisfying result.

Spinal arachnoiditis and syringomyelia: Review of literature with emphasis on postinfectious inflammation and treatment

Background:

Arachnoiditis refers to chronic inflammation of the arachnoid mater and subarachnoid space due to three major etiologies: chemical, mechanical, and postinfectious. As a rare disease with variable symptomatology and severity at presentation, arachnoiditis can be extremely debilitating with many complications, prominent among which is syringomyelia.

Methods:

We reviewed current literature concerning postinfectious spinal arachnoiditis and associated syringomyelia with emphasis on the treatment options that have been used to date and discuss their respective benefits and drawbacks.

Results:

It is critical to understand the natural history and potential complications of patient with postinfectious arachnoiditis. Surgical and medical treatments both have their own merits and demerits. Different surgical approaches have been employed with variable success rates.

Conclusion:

At present, no consensus exists regarding management of these patients due to the variable nature of the disease that affects treatment efficacy; however, surgical intervention in selected cases may be beneficial.

Spinal arachnoid web-a distinct entity of focal arachnopathy with favorable long-term outcome after surgical resection: analysis of a multicenter patient population

BACKGROUND CONTEXT

Spinal arachnoid web (SAW) is a rare condition characterized by focal thickening of the arachnoid membrane causing displacement and compression of the spinal cord with progressive symptoms and neurological deficits. Recent reports and clinical experience suggest that SAW is a distinct entity with specific radiological findings and treatment strategies distinguishable from other arachnopathies and potential differential diagnoses.

PURPOSE

To better define the diagnostic and clinical features, treatment options and outcomes of surgically treated SAW.

STUDY DESIGN

Multicentric retrospective cohort study.

PATIENT SAMPLE

Twelve cases of SAW surgically treated at three different centers.

OUTCOME MEASURES

Self-reported and neurological outcome measurements (pain, sensory-motor deficits, vegetative dysfunctions) were assessed at follow-up timepoints.

METHODS

Retrospective review of prospectively collected data on all patients surgically treated for SAW from three participating neurosurgical centers between 2014 and 2020. Clinicopathological data, including neurological presentation, radiological and histological findings and outcome data were analyzed.

RESULTS

Twelve radiologically and surgically confirmed cases of SAW were analyzed. Mean patient age was 54.7 [±12.7], 67% were male. All SAWs were located in the posterior thoracic dural sac. On magnetic resonance imaging (MRI), the "scalpel sign" - a characteristic focal dorsal indentation of the spinal cord resembling a scalpel blade - was identified in all patients. A focal intramedullary syrinx was present in 83%. Preoperative clinical symptoms included signs of myelopathy, pain, weakness and sensory loss, most commonly affecting the trunk/upper back or lower extremities. Laminectomy or laminoplasty with intradural excision of the SAW was the surgical treatment of choice in all cases. Intraoperative ultrasound was valuable to visualize the cerebrospinal fluid (CSF) flow obstruction, confirm the SAW location before dura incision and to control adequacy of resection. After surgery, sensory loss and weakness in particular showed significant improvement.

CONCLUSIONS

The present study comprises the largest series of surgically treated SAW, underscoring the unique clinical, radiographic, histopathological, and surgical findings. We want to emphasize SAW being a distinct entity of spinal arachnopathy with a favorable long-term outcome if diagnosed correctly and treated surgically. Intraoperative ultrasound aids visualizing the SAW before dural incision, as well as verifying restored CSF flow after resection.

Theco-thecal bypass technique elucidating a novel procedure and perspective on treatment of post-arachnoiditis syringomyelia: A case report

BACKGROUND

Post-arachnoiditis syringomyelia is a condition in which there is an intraspinal cerebrospinal fluid (CSF) blockade due to arachnoidal adhesions and bands. Although many of the techniques currently in use, namely, the theco-peritoneal, syringo-pleural, syringo-peritoneal, and syringo-subarachnoid shunts, are effective, the results are often variable.

CASE SUMMARY

A 36-year-old man with a past history of pulmonary tuberculosis, presented with progressive paraesthesia in the feet and progressive paraparesis along with constipation, difficulty in micturition, and decreased libido. He was bedridden a month before presentation. Magnetic resonance imaging revealed a dorsal multiloculated syrinx from D3-D10 vertebral levels. He underwent a D1-2 to D11 theco-thecal shunt bilaterally to abolish the CSF gradient across the level of the syrinx. There was no direct surgical handling of the spinal cord involved. At the 15-mo follow up, the patient had significant improvement in his symptoms and function.

CONCLUSION

We present a novel technique aimed at correcting the primary cause of a post-arachnoiditis syrinx, the subarachnoid cerebrospinal flow obstruction or block, which we believe is simple and effective, involves minimal handling of the normal neural structures, and attempts to restore the physiology of CSF flow across the obstruction, with favorable clinical results.

Thoracolumbar meningeal fibrosis in pugs

Background

Thoracolumbar myelopathies associated with spinal cord and vertebral column lesions, with a similar clinical phenotype, but different underlying etiologies, occur in pugs.

Objectives

To further characterize the clinical and neuropathological characteristics of pugs with longstanding thoracolumbar myelopathy.

Animals

Thirty client‐owned pure‐bred pugs with a history of more than a month of ataxia and paresis of the pelvic limbs, suggesting a myelopathy localized to the thoracolumbar spinal cord, were included in the study.

Methods

Prospective clinicopathological study. Included pugs underwent a complete neurological examination and gross and histopathologic postmortem studies with focus on the spinal cord. Computed tomography (n = 18), magnetic resonance imaging (n = 17), and cerebrospinal fluid analysis (n = 27) were performed before or immediately after death.

Results

Twenty male and 10 female pugs had a median age at clinical onset of 84 months (interquartile range, 66‐96). Affected pugs presented with a progressive clinical course and 80% were incontinent. There was circumferential meningeal fibrosis with concomitant focal, malacic, destruction of the neuroparenchyma in the thoracolumbar spinal cord in 24/30 pugs. Vertebral lesions accompanied the focal spinal cord lesion, and there was lympho‐histiocytic inflammation associated or not to the parenchymal lesion in 43% of the pugs.

Conclusions and Clinical Importance

Meningeal fibrosis with associated focal spinal cord destruction and neighboring vertebral column lesions were common findings in pugs with long‐standing thoracolumbar myelopathy.

Intruding implements: a pictorial review of retained surgical foreign objects in neuroradiology

Intra-cranial and spinal foreign body reactions represent potential complications of medical procedures. Their diagnosis may be challenging as they frequently show an insidious clinical presentation and can mimic other life-threatening conditions. Their pathophysiological mechanism is represented by a local inflammatory response due to retained or migrated surgical elements. Cranial interventions may be responsible for the presence of retained foreign objects represented by surgical materials (such as sponges, bone wax, and Teflon). Spinal diagnostic and therapeutic procedures, including myelography, chordotomy, vertebroplasty, and device implantation, are another potential source of foreign bodies. These reactions can also follow material migration or embolization, for example in the case of Lipiodol, Teflon, and cement vertebroplasty. Imaging exams, especially CT and MRI, have a central role in the differential diagnosis of these conditions together with patient history. Neuroradiological findings are dependent on the type of material that has been left in or migrated from the surgical area. Knowledge of these entities is relevant for clinical practice as the correct identification of foreign bodies and related inflammatory reactions, material embolisms, or migrations can be difficult. This pictorial review reports neuroradiological semeiotics and differential diagnosis of foreign body-related imaging abnormalities in the brain and spine.

Safety and Efficacy of Syringoperitoneal Shunting with a Programmable Shunt Valve for Syringomyelia Associated with Extensive Spinal Adhesive Arachnoiditis: Technical Note

OBJECTIVE

Although syringomyelia associated with extensive spinal adhesive arachnoiditis (SAA) can be a progressive disease that has potentially devastating clinical consequences, its surgical resolution has remained poorly defined. The aim of the present study was to verify the safety and efficacy of syringoperitoneal shunting for syringomyelia associated with extensive SAA.

METHODS

The present retrospective study included 15 patients who had undergone syringoperitoneal shunting with a programmable shunt valve for the diagnosis of syringomyelia associated with extensive SAA from October 2012 to June 2018. The shunt pressure was appropriately adjusted according to the postoperative sequential clinical condition and change in syringomyelia evaluated using magnetic resonance imaging. The average postoperative follow-up duration was 32.7 months.

RESULTS

No surgery-related complications such as shunt dysfunction or infection occurred during the follow-up period, except for 2 patients with minor issues with the shunt tube. The average shunt pressure at the last follow-up examination was 4.5 cm H₂O. The findings from the clinical assessment suggested that the average grade on the sensory pain scale was 2.9 before surgery and had improved significantly to 2.5 at the most recent follow-up examination. Radiological analysis suggested that improvement of syringomyelia was noted in 14 of the 15 patients (93.3%), with no cases of radiological aggravation. No recurrence of syringomyelia developed during the follow-up period in the present study.

CONCLUSION

Syringoperitoneal shunting with a programmable shunt valve was safe and effective for clinical control of syringomyelia associated with extensive SAA. Long-term follow-up is mandatory to monitor for shunt dysfunction and mechanical trouble.

Practical applications of CISS MRI in spine imaging

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Conventional spin echo imaging is limited by low spatial resolution and CSF pulsation artifact.

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CISS MRI enables submillimeter spatial resolution and myelographic contrast.

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Inherent flow compensation of the CISS technique reduces CSF pulsation artifact.

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CISS improves the delineation of a wide variety of spinal pathologies.

Routine magnetic resonance imaging evaluation of the spine is often limited by low spatial resolution and artifacts resulting from cerebrospinal fluid pulsation. Balanced steady-state free precession sequences can supplement routine spin echo sequences and provide exquisite anatomic detail and high cerebrospinal fluid-to-soft tissue contrast, adding significant diagnostic value to the evaluation of a wide variety of spine disorders.

Imaging Appearance of Advanced Chronic Adhesive Arachnoiditis: A Retrospective Review

OBJECTIVE

Chronic adhesive arachnoiditis (CAA) is rare and has potentially devastating clinical consequences. The objective of this article is to review the clinical features of CAA and describe its appearance on imaging, to increase radiologists' awareness of this challenging diagnosis.

MATERIALS AND METHODS

Twenty-nine cases of advanced CAA seen at our institution over 18 years (1995-2013) were retrospectively reviewed. Chart review was performed, with attention given to data on clinical presentation, suspected cause, and interventions performed. All patients underwent MRI, and seven patients also underwent CT myelography. Clinical and imaging features were evaluated and categorized.

RESULTS

The 29 patients ranged in age from 23 to 96 years and included 11 women and 18 men. Suspected underlying causative factors included trauma (n = 10), prior surgery (n = 9), nontraumatic subarachnoid hemorrhage (n = 7), infection (n = 3), myelography with iophendylate used as contrast medium (n = 1), Guillain-Barré syndrome (n = 1), ankylosing spondylitis (n = 1), and unknown causes (n = 1). Imaging characteristics include loculated CSF collections (n = 23), nerve root clumping, enhancement, and displacement (n = 15), cord swelling with increased T2 signal (n = 12), arachnoid septations (n = 11), cord atrophy (n = 6), syrinx (n = 5), and intrathecal calcifications (n = 3). Ten patients underwent surgical procedures, and most had only brief clinical improvement.

CONCLUSION

CAA is a rare cause of devastating neurologic symptoms and chronic pain. The imaging features of CAA range from subtle to severe. Advanced arachnoiditis can present with spinal cord swelling and syrinx formation, which can mimic other disease processes. Inclusion of advanced CAA in the differential diagnosis can prevent unnecessary interventions.

Imaging of noninfectious inflammatory disorders of the spinal cord

Myelitis, or inflammation of the spinal cord, produces a characteristic clinical syndrome. Among the many causes of myelitis are the prototypical demyelinating diseases multiple sclerosis and neuromyelitis optica, each of which has distinct clinical, pathologic, and radiographic features. Less distinct are the myelitides associated with systemic autoimmune conditions like sarcoidosis and lupus. Nondemyelinating conditions such as arachnoiditis, dural arteriovenous fistula, and tumor infiltration may also produce inflammation of the spinal cord. The objective of this review is to aid the clinician in the radiographic diagnosis of noninfectious inflammatory diseases of the spinal cord.

Sudden death and cervical spine: A new contribution to pathogenesis for sudden death in critical care unit from subarachnoid hemorrhage; first report - An experimental study

Context:

Sudden death from subarachnoid hemorrhage (SAH) is not uncommon.

Aims:

The goal of this study is to elucidate the effect of the cervical spinal roots and the related dorsal root ganglions (DRGs) on cardiorespiratory arrest following SAH.

Settings and Design:

This was an experimental study conducted on rabbits.

Materials and Methods:

This study was conducted on 22 rabbits which were randomly divided into three groups: control (n = 5), physiologic serum saline (SS; n = 6), SAH groups (n = 11). Experimental SAH was performed. Seven of 11 rabbits with SAH died within the first 2 weeks. After 20 days, other animals were sacrificed. The anterior spinal arteries, arteriae nervorum of cervical nerve roots (C6–C8), DRGs, and lungs were histopathologically examined and estimated stereologically.

Statistical Analysis Used:

Statistical analysis was performed using the PASW Statistics 18.0 for Windows (SPSS Inc., Chicago, Illinois, USA). Intergroup differences were assessed using a one-way ANOVA. The statistical significance was set at P < 0.05.

Results:

In the SAH group, histopathologically, severe anterior spinal artery (ASA) and arteriae nervorum vasospasm, axonal and neuronal degeneration, and neuronal apoptosis were observed. Vasospasm of ASA did not occur in the SS and control groups. There was a statistically significant increase in the degenerated neuron density in the SAH group as compared to the control and SS groups (P < 0.05). Cardiorespiratory disturbances, arrest, and lung edema more commonly developed in animals in the SAH group.

Conclusion:

We noticed interestingly that C6–C8 DRG degenerations were secondary to the vasospasm of ASA, following SAH. Cardiorespiratory disturbances or arrest can be explained with these mechanisms.

Subarachnoid-subarachnoid bypass for spinal adhesive arachnoiditis

The authors report a case of adhesive arachnoiditis (AA) and arachnoid cyst successfully treated by subarachnoid to subarachnoid bypass (S-S bypass). Arachnoid cysts or syringes sometimes compress the spinal cord and cause compressive myelopathy that requires surgical treatment. However, surgical treatment for AA is challenging. A 57-year-old woman developed leg pain and gait disturbance. A dorsal arachnoid cyst compressed the spinal cord at T7-9, the spinal cord was swollen, and a small syrinx was present at T9-10. An S-S bypass was performed from T6-7 to T11-12. The patient's gait disturbance resolved immediately after surgery. Two years later, a small arachnoid cyst developed. However, there was no neurological deterioration. The myelopathy associated with thoracic spinal AA, subarachnoid cyst, and syrinx improved after S-S bypass.

Transplantation of autologous olfactory ensheathing cells in complete human spinal cord injury

Numerous studies in animals have shown the unique property of olfactory ensheathing cells to stimulate regeneration of lesioned axons in the spinal cord. In a Phase I clinical trial, we assessed the safety and feasibility of transplantation of autologous mucosal olfactory ensheathing cells and olfactory nerve fibroblasts in patients with complete spinal cord injury. Six patients with chronic thoracic paraplegia (American Spinal Injury Association class A-ASIA A) were enrolled for the study. Three patients were operated, and three served as a control group. The trial protocol consisted of pre- and postoperative neurorehabilitation, olfactory mucosal biopsy, culture of olfactory ensheathing cells, and intraspinal cell grafting. Patient's clinical state was evaluated by clinical, neurophysiological, and radiological tests. There were no adverse findings related to olfactory mucosa biopsy or transplantation of olfactory ensheathing cells at 1 year after surgery. There was no evidence of neurological deterioration, neuropathic pain, neuroinfection, or tumorigenesis. In one cell-grafted patient, an asymptomatic syringomyelia was observed. Neurological improvement was observed only in transplant recipients. The first two operated patients improved from ASIA A to ASIA C and ASIA B. Diffusion tensor imaging showed restitution of continuity of some white matter tracts throughout the focus of spinal cord injury in these patients. The third operated patient, although remaining ASIA A, showed improved motor and sensory function of the first spinal cords segments below the level of injury. Neurophysiological examinations showed improvement in spinal cord transmission and activity of lower extremity muscles in surgically treated patients but not in patients receiving only neurorehabilitation. Observations at 1 year indicate that the obtaining, culture, and intraspinal transplantation of autologous olfactory ensheathing cells were safe and feasible. The significance of the neurological improvement in the transplant recipients and the extent to which the cell transplants contributed to it will require larger numbers of patients.

Treatment of Syringomyelia Related to Nontraumatic Arachnoid Pathologies of the Spinal Canal

BACKGROUND:

Disturbances of cerebrospinal fluid (CSF) flow are the commonest cause of syringomyelia. Spinal arachnopathies may lead to CSF flow obstructions but are difficult to diagnose. Consequently, associated syringomyelias are often categorized as idiopathic.

OBJECTIVE:

To present and analyze the diagnosis of and long-term outcomes in an observational study of patients with nontraumatic arachnopathies from 1991 to 2011.

METHODS:

A total of 288 patients (mean age, 47 ± 15 years; follow-up, 54 ± 46 months) were evaluated. Decompression with arachnolysis, untethering, and duraplasty for restoration of CSF flow was recommended to patients with neurological progression. Neurological examinations, magnetic resonance images, and follow-up data were evaluated. Individual symptoms were analyzed during the first postoperative year, and long-term outcomes were analyzed with Kaplan-Meier statistics to determine rates of progression-free survival.

RESULTS:

In total,189 patients either refused an operation or were managed conservatively for lack of progression. Among 79 unoperated patients with follow-up information available for up to 8 years, 2 patients deteriorated. Ninety-nine patients with progressive symptoms underwent 116 operations: 108 decompressions and 8 other surgeries. Three months postoperatively, 53% considered their status improved and 37% were unchanged. In the long term, surgery on arachnopathies limited to 2 spinal segments was followed by progression-free survival for 78% over 10 years, in contrast to 31% with extensive arachnopathies.

CONCLUSION:

Surgery on nontraumatic arachnopathies related to syringomyelia should be reserved for patients with progressive symptoms. Arachnolysis, untethering, and duraplasty provide good long-term results for focal arachnopathies. For extensive pathologies with a history of subarachnoid hemorrhage or meningitis, treatment remains a major challenge.