Arachnoscopy: a special application of spinal intradural endoscopy

Ticagrelor Aspirin vs Clopidogrel Aspirin in CYP2C19 Loss-of-Function Carriers With Minor Stroke or TIA Stratified by Risk Profile

BACKGROUND AND OBJECTIVE

Genotype data of the Clopidogrel with Aspirin in Acute Minor Stroke or Transient Ischemic Attack (CHANCE) trial showed that efficacy of clopidogrel aspirin depended on CYP2C19 genotype and risk profile. A stratification of patients who carried CYP2C19 loss-of-function (LOF) alleles according to the risk of recurrent stroke may be important for selecting optimal antiplatelet therapy. We aimed to compare the efficacy and safety of ticagrelor aspirin with clopidogrel aspirin in CYP2C19 LOF carriers with minor stroke or transient ischemic attack (TIA) stratified by risk profile.

METHODS

Data were obtained from Ticagrelor or Clopidogrel with Aspirin in High-Risk Patients with Acute Nondisabling Cerebrovascular Events II (CHANCE-2) trial. Low-risk and high-risk profiles were defined by Essen Stroke Risk Score (ESRS) (<3 [low risk] and ≥3 [high risk], respectively).

RESULTS

A total of 6,412 CYP2C19 LOF carriers were enrolled; ticagrelor aspirin was associated with a reduced risk of primary outcome (new stroke within 90-day follow-up) in patients at low risk (hazard ratio [HR], 0.65; 95% CI, 0.48-0.82), but not in those at high risk (HR, 0.97; 95% CI, 0.73-1.29), compared with clopidogrel aspirin (p = 0.02 for interaction). Secondary outcomes generally went in the same direction as the primary outcome. The primary safety outcome of severe or moderate bleeding did not differ based on risk profile (p = 0.24 for interaction), although the incidence of total bleeding was greater with ticagrelor aspirin than with clopidogrel aspirin among patients at low risk (p < 0.01 for interaction). Analysis in the per-protocol population yielded similar results.

DISCUSSION

This post hoc analysis of CHANCE-2 trial showed that CYP2C19 LOF carriers with minor stroke or TIA at low risk of recurrent stroke received a greater benefit from ticagrelor aspirin than from clopidogrel aspirin.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that CYP2C19 LOF carriers with minor stroke or TIA at low risk, but not at high risk, of recurrent stroke (by the ESRS) received a greater benefit from ticagrelor aspirin than from clopidogrel aspirin.

TRIAL REGISTRATION INFORMATION

URL: www.

CLINICALTRIALS

gov. Unique identifier: NCT04078737.

The leptomeninges as a critical organ for normal CNS development and function: First patient and public involved systematic review of arachnoiditis (chronic meningitis)

BACKGROUND & IMPORTANCE

This patient and public-involved systematic review originally focused on arachnoiditis, a supposedly rare "iatrogenic chronic meningitis" causing permanent neurologic damage and intractable pain. We sought to prove disease existence, causation, symptoms, and inform future directions. After 63 terms for the same pathology were found, the study was renamed Diseases of the Leptomeninges (DLMs). We present results that nullify traditional clinical thinking about DLMs, answer study questions, and create a unified path forward.

METHODS

The prospective PRISMA protocol is published at Arcsology.org. We used four platforms, 10 sources, extraction software, and critical review with ≥2 researchers at each phase. All human sources to 12/6/2020 were eligible for qualitative synthesis utilizing R. Weekly updates since cutoff strengthen conclusions.

RESULTS

Included were 887/14286 sources containing 12721 DLMs patients. Pathology involves the subarachnoid space (SAS) and pia. DLMs occurred in all countries as a contributor to the top 10 causes of disability-adjusted life years lost, with communicable diseases (CDs) predominating. In the USA, the ratio of CDs to iatrogenic causes is 2.4:1, contradicting arachnoiditis literature. Spinal fusion surgery comprised 54.7% of the iatrogenic category, with rhBMP-2 resulting in 2.4x more DLMs than no use (p<0.0001). Spinal injections and neuraxial anesthesia procedures cause 1.1%, and 0.2% permanent DLMs, respectively. Syringomyelia, hydrocephalus, and arachnoid cysts are complications caused by blocked CSF flow. CNS neuron death occurs due to insufficient arterial supply from compromised vasculature and nerves traversing the SAS. Contrast MRI is currently the diagnostic test of choice. Lack of radiologist recognition is problematic.

DISCUSSION & CONCLUSION

DLMs are common. The LM clinically functions as an organ with critical CNS-sustaining roles involving the SAS-pia structure, enclosed cells, lymphatics, and biologic pathways. Cases involve all specialties. Causes are numerous, symptoms predictable, and outcomes dependent on time to treatment and extent of residual SAS damage. An international disease classification and possible treatment trials are proposed.

Endoscopic treatment of spinal arachnoid cysts

Background/objective

Spinal arachnoid cysts (SAC) are intradural lesions, which may provoke a compression of the spinal cord and roots. Endoscopic techniques are increasingly used to minimize the surgical access and the postoperative scar tissue. Shunts may also represent an option. The aim of this paper is to illustrate the technique of endoscopic-assisted fenestration and positioning of a cysto-peritoneal diversion in a thoracic SAC using a flexible endoscope and to perform a systematic literature review on this subject.

Material and methods

We reported our case and we performed a review of the literature, searching for all the adult cases of Type III SACs in English language treated through endoscopic procedures.

Results

We found 5 articles matching our search criteria and we included 9 adult patients in our analysis. Six patients were females and the most common localization was the thoracic spine. Six patients underwent selective laminectomies followed by endoscopic fenestration without cyst wall resection. Three patients had a percutaneous endoscopic inspection of the cyst and in two cases a cysto-subarachnoid shunt space was performed. Improvement of pre-operative neurological deficit was reported in six patients, no patients experienced clinical deterioration. The mean follow-up was 22 months and no progression or recurrence was reported.

Conclusion

The implementation of endoscopy allows a minimally invasive treatments with good visualization of cyst anatomy and precise shunt positioning under real-time guidance. Endoscopy is technically demanding but it can offer similar clinical outcomes when compared to microscopic procedures with a limited rate of post-operative complications.

The long-term risk of recurrence should be established by prospective studies.

Use of an endoscope for spinal intradural pathology

The endoscope has been increasingly used to treat various spinal diseases. However, the application of spinal endoscopy in an intradural lesion has been less common compared to that of an epidural counterpart. The authors reviewed existing literature describing spinal endoscopy as an aid in surgical treatment for intradural pathologies. Importantly, available literature indicated the safety and feasibility of spinal endoscopy for intradural lesions. Especially, an endoscope was utilized for intradural subarachnoid cystic lesions, tethered cord syndrome, extramedullary tumors, spinal arteriovenous malformations, and cordectomy for intractable pain. The results of this review should enhance further development and broaden application of an endoscope for various intradural pathologies.

Endoscopic-Assisted Spinal Arachnoiditis Adhesiolysis and Placement of a Spinal Cysto-Subarachnoid Shunt

BACKGROUND

Spinal arachnoiditis and associated arachnoid adhesions can cause debilitating neurological symptoms due to nerve root and spinal cord compression or tethering. Adhesiolysis using a microscopic approach has traditionally been used for this condition. This procedure has been further refined in recent years with the use of flexible endoscopes.

CASE DESCRIPTION

We report the case of a patient with progressive thoracic myelopathy secondary to arachnoid adhesions associated with arachnoiditis. A minimally invasive technique of adhesiolysis and placement of a cysto-arachnoid shunt was performed with the assistance of a flexible endoscope.

CONCLUSIONS

The present case report has highlighted the advantages of using a flexible endoscope to treat spinal arachnoiditis adhesiolysis and placement of a cysto-arachnoid shunt, including a smaller skin incision and extended visualization.

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.

Treatment of Posttubercular Syringomyelia Not Responsive to Antitubercular Therapy: Case Report and Review of Literature

Posttubercular adhesive arachnoiditis is a rare, late complication of tubercular meningitis. Syringomyelia can develop as a consequence of intramedullary cystic lesions and cerebrospinal fluid (CSF) flow disturbance around the spinal cord, even after successful chemotherapy. We reviewed the literature related to posttubercular syringomyelia treatment and suggest a new combined surgical approach. A 25-year-old Nigerian male patient presented with legs numbness, urinary disturbance, and legs weakness. Spinal magnetic resonance revealed a T5-T7 syringomyelia, secondary to adhesive spinal arachnoiditis related to a history of tuberculous meningitis. Adhesiolysis by direct visualization with a flexible endoscope was performed and a handmade S-italic syringe-subdural shunt was placed to restore CSF flow. During the postoperative course, the neurological deficits improved together with the resolution of the syrinx. Long-term magnetic resonance imaging follow-up documented no recurrences or shunt displacements. We suggest that, when antitubercular therapy is not effective to resolve postarachnoiditis syrinx, arachnolysis with a flexible endoscope together with the placement of an S-italic shunt allowed free CSF communication between the syrinx and the subarachnoid space. Furthermore, we support that the use of an s-shaped shunt could prevent displacement or migration of the device and allows an easier revision in case of acute or late complications.

A New Classification for Pathologies of Spinal Meninges—Part 2: Primary and Secondary Intradural Arachnoid Cysts

BACKGROUND: Spinal intradural arachnoid cysts are rare causes of radiculopathy or myelopathy. Treatment options include resection, fenestration, or cyst drainage.

OBJECTIVE: To classify intradural spinal arachnoid cysts and present results of their treatment.

METHODS: Among 1519 patients with spinal space occupying lesions, 130 patients demonstrated intradural arachnoid cysts. Neuroradiological and surgical features were reviewed and clinical data analyzed.

RESULTS: Twenty-one patients presented arachnoid cysts as a result of an inflammatory leptomeningeal reaction related to meningitis, subarachnoid hemorrhage, intrathecal injections, intradural surgery, or trauma, ie, secondary cysts. For the remaining 109 patients, no such history could be elucidated, ie, primary cysts. Forty-six percent of primary and 86% of secondary cysts were associated with syringomyelia. Patients presented after an average history of 53 ± 88 months. There were 122 thoracic and 7 lumbar cysts plus 1 cervical cyst. Fifty-nine patients with primary and 15 patients with secondary cysts underwent laminotomies with complete or partial cyst resection and duraplasty. Mean follow-up was 57 ± 52 months. In the first postoperative year, profound improvements for primary cysts were noted, in contrast to marginal changes for secondary cysts. Progression-free survival for 10 years following surgery was determined as 83% for primary compared to 15% for secondary cysts. Despite differences in clinical presentation, progression-free survival was almost identical for patients with or without syringomyelia.

CONCLUSIONS: Complete or partial resection leads to favorable short- and long-term results for primary arachnoid cysts. For secondary cysts, surgery can only provide clinical stabilization for a limited time due to the often extensive arachnoiditis.

Minimally invasive removal of lumbar intradural extramedullary lesions using the interlaminar approach

OBJECT Posterior midline laminectomy or hemilaminectomy has been successfully applied as the standard microsurgical technique for the treatment of spinal intradural pathologies. However, the associated risks of postoperative spinal instability increase the need for subsequent fusion surgery to prevent potential long-term spinal deformity. Continuous efforts have been made to minimize injuries to the surrounding tissue resulting from surgical manipulations. The authors report here their experiences with a novel minimally invasive surgical approach, namely the interlaminar approach, for the treatment of lumbar intraspinal tumors. METHODS A retrospective review was conducted of patients at the Second Affiliated Hospital of Zhejiang University School of Medicine who underwent minimally invasive resection of lumbar intradural-extramedullary tumors. By using an operative microscope, in addition to an endoscope when necessary, the authors were able to treat all patients with a unilateral, paramedian, bone-sparing interlaminar technique. Data including preoperative neurological status, tumor location, size, pathological diagnosis, extension of resections, intraoperative blood loss, length of hospital stay, and clinical outcomes were obtained through clinical and radiological examinations. RESULTS Eighteen patients diagnosed with lumbar intradural-extramedullary tumors were treated from October 2013 to March 2015 by this interlaminar technique. A microscope was used in 15 cases, and the remaining 3 cases were treated using a microscope as well as an endoscope. There were 14 schwannomas, 2 ependymomas, 1 epidermoid cyst, and 1 enterogenous cyst. Postoperative radiological follow-up revealed complete removal of all the lesions and no signs of bone defects in the lamina. At clinical follow-up, 14 of the 18 patients had less pain, and patients' motor/sensory functions improved or remained normal in all cases except 1. CONClUSIONS When meeting certain selection criteria, intradural-extramedullary lumbar tumors, especially schwannomas, can be completely and safely resected through a less-invasive interlaminar approach using a microscope, or a microscope in addition to an endoscope when necessary. This approach was advantageous because it caused even less bone destruction, resulting in better postoperative spinal stability, no need for facetectomy and fusion, and quicker functional recovery for the patients. Individualized surgical planning according to preoperative radiological findings is key to a successful microsurgical resection of these lesions through the interlaminar space.

Operative management of idiopathic spinal intradural arachnoid cysts in children: a systematic review

BACKGROUND

Spinal intradural arachnoid cysts are rare with only a few patients reported so far. Idiopathic, traumatic, posthemorrhagic, and postinflammatory causes have been reported in the literature. Especially, idiopathic lesions, in which other possible etiological factors have been ruled out, seem to be rare.

PATIENTS AND METHODS

We systematically reviewed the literature in regards to localization within the spinal canal, treatment options, complications, and outcome. Additionally, we present management strategies in two progressively symptomatic children less than 3 years of age with idiopathic intradural arachnoid cysts.

RESULTS

In total, 21 pediatric cases including the presented cases have been analyzed. Anterior idiopathic spinal arachnoid cysts are predominantly located in the cervical spine in 87.5 % of all cases, whereas posterior cysts can be found at thoracic and thoracolumbar segments in 84.6 % of the patients. Most children presented with motor deficits (76.2 %). Twenty-five percent of anterior spinal arachnoid cysts caused back pain as the only presenting symptom. Open fenestration by a dorsal approach has been used in the vast majority of cases. No major surgical complications have been reported. Ninety-four percent of all patients did improve or showed no neurological deficits. Recurrence rate after successful surgical treatment was low (9.5 %).

CONCLUSION

Idiopathic spinal intradural arachnoid cysts can present with neurological deficits in children. Pathologies are predominantly located in the cervical spine anteriorly and in thoracic and thoracolumbar segments posteriorly to the spinal cord. In symptomatic cases, microsurgical excision and cyst wall fenestration via laminotomy are recommended. Our radiological, intraoperative, and pathological findings support the cerebrospinal fluid obstruction and vent mechanism theory of arachnoid cysts.

Amelioration of caudal thoracic syringohydromyelia following surgical management of an adjacent arachnoid cyst

A nine-year-old male, neutered, pug was presented for investigation of progressive ambulatory paraparesis and pelvic limb ataxia of three months' duration. Magnetic resonance imaging was suggestive of caudal thoracic syringohydromyelia with an adjacent intradural arachnoid cyst. The cyst was marsupialised following dorsal laminectomy. Neurological status had improved 10 weeks following surgery when repeat magnetic resonance imaging revealed reduced spinal cord compression both as a result of resolution of the cyst and reduction in size of the syringohydromyelia. At 17 months following surgery, the dog showed further improvements in neurological status, exhibiting mild pelvic limb ataxia and proprioceptive deficits. Improved cerebrospinal fluid flow following surgery may have played a role in the improvement in both conditions. The presence of syringohydromyelia in this context does not preclude a favourable clinical outcome following surgical management.