Full endoscopic resection of large bilateral synovial cysts in lumbar spine.

Synovial spinal cysts cause radiculopathy and back pain, with rare reports of cauda equina syndrome. Hypermobility and instability are cornerstones for synovial cyst formation. The incidence is around 5%, and data for bilateral cysts are lacking. Surgery is indicated after conservative measures fail. Recurrence is common and is potentially due to joint violation and destabilization from open surgery. This could be prevented via ultra-minimally invasive approaches. The authors present full endoscopic removal of bilateral synovial cysts in a patient with grade 1 stable spondylolisthesis and include a 360° view for confirmation of complete decompression. Postoperatively, the patient reported immediate pain relief. The video can be found here: https://stream.cadmore.media/r10.3171/2024.1.FOCVID23208.

Full endoscopic resection of ventral thoracic osteophyte and repair of spontaneous CSF leak.

Spontaneous CSF leaks frequently cause headaches, meningismus, and nausea due to intracranial hypotension. When conservative treatment fails, surgical repair is indicated. Especially ventral leaks necessitate invasive approaches with substantial blood loss and tissue trauma. Full endoscopic spine surgery (FESS) enables circumferential access via the transforaminal approach. Here, the authors show the successful repair of a ventral CSF leak in the thoracic spine after removal of bony osteophytes utilizing FESS with placement of a dural substitute and sealant. Lasting symptom relief was reported. These results suggest that FESS is safe and efficient for the repair of spontaneous and incidental CSF leaks. The video can be found here: https://stream.cadmore.media/r10.3171/2024.1.FOCVID23209.

Full Endoscopic Repair of Spontaneous Ventral Cerebrospinal Fluid Leaks in the Spine: Systematic Review of Surgical Treatment Options and Illustrative Case.

BACKGROUND: Spontaneous spinal cerebrospinal fluid (CSF) leaks are a rare entity that can lead to intracranial hypotension and associated headaches, meningismus, and patient debility. Surgical treatment may be necessary for patients who do not respond to conservative management. Surgical repair of CSF leaks located in the ventral thoracic spine traditionally require an invasive, open approach. METHODS: We describe the case of a patient with a ventral thoracic spontaneous spinal CSF leak associated with a ventral bony osteophyte successfully treated with spinal endoscopy. We also provide a systematic review of the literature to better understand outcomes of this approach. RESULTS: A total of 55 patients were included in the systematic review. The study designs found in the literature review included case reports (66.7%), retrospective cohorts (22.2%), and prospective cohorts (11.1%). Of the studies reporting data, 50% of studies stated they used an open posterior approach to the dural defect, while 37.5% reported using an open anterior approach to the pathology. Only 1 (12.5%) study reported using an endoscope. Most studies (62.5%) used primary closure of the dura in their technique, while 37.5% reported using a local tissue graft (fat or muscle) or a dural sealant for their closure technique, and 25% of studies reported using a dural substitute for their closure technique. Overall mean clinical follow-up was 19.8 months. CONCLUSIONS: The endoscopic approach described here for treatment of this rare entity allows for removal of bony spicules/osteophytes and dural repair without the morbidity associated with traditional open dorsolateral or ventrolateral approaches.

Outpatient endoscopic resection of large calcified thoracic disc herniation with caudal displacement.

Thoracic disc herniations can cause radiculopathy and myelopathy from neural compression. Surgical resection may require complex, morbid approaches. To avoid spinal cord retraction, wide exposures requiring extensive tissue, muscle, and bony disruption are needed, which may require instrumentation. Anterior approaches may require vascular surgeons, chest tube placement, and intensive care admission. Large, calcified discs or migrated fragments can pose additional challenges. Previous literature has noted the endoscopic approach to be contraindicated for calcified thoracic discs. The authors describe an ultra-minimally invasive, ambulatory endoscopic approach to resect a large calcified thoracic disc with caudal migration and avoidance of conventional approaches. The video can be found here: https://stream.cadmore.media/r10.3171/2021.10.FOCVID2112.

Treatment of Refractory Multilevel Thoracic Spondylodiscitis Using Ultra-Minimally Invasive Endoscopic Approach for Debridement and Drainage: A Technical Note, Intraoperative Video, and Literature Review.

OBJECTIVE/BACKGROUND: Spondylodiscitis is an infection of the spinal column which can result in pain, deformity, instability, and/or neurologic deficits. When surgical treatment is required for thoracic spondylodiscitis, invasive open approaches are often utilized due to the ventral location of the pathology. METHODS: We describe the use of a spinal endoscope to perform drainage and debridement of infected tissue through a transforaminal/intradiscal approach in a patient with multilevel thoracic spondylodiscitis refractory to antibiotic therapy. Illustrative videos are provided, as well as a review of the relevant literature. RESULTS: A total of 188 patients were included in the systematic review. The mean positive reported culture rate was 76% (117/154 patients). The mean preoperative visual analog scale score was 6.8 (n = 114), and the mean postoperative visual analog scale score was 1.8 at 1 week postoperatively (n = 56) and 1.01 at the final follow-up (n = 114). The most common surgical approach was transforaminal/intradiscal (103/188 patients, 54.8%). The mean reoperation rate was 9.1%. The mean complication rate was 5.25%, with complications including increased transient radicular pain, infection, hardware failure, and new unspecified neurological deficits. CONCLUSION: This case and those highlighted in our literature review demonstrate that endoscopic treatment for thoracic spondylodiscitis is a viable alternative to traditional open surgery in many cases.

The Role of the Endoscope in Spinal Oncology: A Systematic Review of Applications and Systematic Analysis of Patient Outcomes.

INTRODUCTION: Surgical techniques to treat tumors of the spine often require extensive tissue dissection and bony removal, predisposing patients to elevated risk for perioperative morbidity and mortality. When indicated, minimally invasive surgical techniques may be preferred as they result in less collateral damage and quicker recovery times. Full endoscopic spine surgery (FES) represents an ultra-minimally invasive approach that further minimizes tissue damage. The advantages to the application of FES to treat spinal tumors remain unclear. METHODS: Electronic databases were systematically searched for published literature on the application of FES in spinal oncology to assess its utility, safety, and outcomes via Nurick, McCormick, and Frankel grades, visual analog scale, complication rate, duration of surgery, estimated blood loss, length of stay, and mean follow-up. RESULTS: Fifteen articles describing 72 patients met inclusion criteria. The most common approach was the interlaminar approach (40.98%). The most common spinal level was lumbar (38.89%). The most common goal of surgery was gross total resection (82.11%). The average Nurick grade decreased from 2.96 to 0.67. All patients showed an improvement from Frankel grade C or D to grade E except for one. The average visual analog scale score decreased from 9.3 to 1.3. The complication rate was 6.56%. The average length of stay was 55.2 hours. The average estimated blood loss was 49 mL. The average duration of surgery was 121.26 minutes. The mean follow-up was 10.58 months. CONCLUSION: The utility of FES in spinal oncology is not well understood. Literature results of this technique show promise. Further study is needed to draw definitive conclusions on FES efficacy and safety in spinal oncology.

Genome-wide Association Analysis Across 16,956 Patients Identifies a Novel Genetic Association Between BMP6, NIPAL1, CNGA1 and Spondylosis.

STUDY DESIGN: A case-control genome-wide association study (GWAS) on spondylosis. OBJECTIVE: Leveraging Geisinger's MyCode initiative's multimodal dataset, we aimed to identify genetic associations with degenerative spine disease. SUMMARY OF BACKGROUND DATA: Degenerative spine conditions are a leading cause of global disability; however, the genetic underpinnings of these conditions remain under-investigated. Previous studies using candidate-gene approach suggest a genetic risk for degenerative spine conditions, but large-scale GWASs are lacking. METHODS: We identified 4434 patients with a diagnosis of spondylosis using ICD diagnosis codes with genotype data available. We identified a population-based control of 12,522 patients who did not have any diagnosis for osteoarthritis. A linear-mix, additive genetic model was employed to perform the genetic association tests adjusting for age, sex, and genetic principal components to account for the population structure and relatedness. Gene-based association tests were performed and heritability and genetic correlations with other traits were investigated. RESULTS: We identified a genome-wide significant locus at rs12190551 (odds ratio = 1.034, 95% confidence interval 1.022-1.046, P = 8.5 × 10-9, minor allele frequency = 36.9%) located in the intron of BMP6. Additionally, NIPAL1 and CNGA1 achieved Bonferroni significance in the gene-based association tests. The estimated heritability was 7.19%. Furthermore, significant genetic correlations with pain, depression, lumbar spine bone mineral density, and osteoarthritis were identified. CONCLUSION: We demonstrated the use of a massive database of genotypes combined with electronic health record data to identify a novel and significant association spondylosis. We also identified significant genetic correlations with pain, depression, bone mineral density, and osteoarthritis, suggesting shared genetic etiology and molecular pathways with these phenotypes.Level of Evidence: N/A.

Effects of White Matter Hyperintensities on 90-Day Functional Outcome after Large Vessel and Non-Large Vessel Stroke.

INTRODUCTION: White matter hyperintensity (WMH) burden is a critically important cerebrovascular phenotype related to the diagnosis and prognosis of acute ischemic stroke. The effect of WMH burden on functional outcome in large vessel occlusion (LVO) stroke has only been sparsely assessed, and direct LVO and non-LVO comparisons are currently lacking. MATERIAL AND METHODS: We reviewed acute ischemic stroke patients admitted between 2009 and 2017 at a large healthcare system in the USA. Patients with LVO were identified and clinical characteristics, including 90-day functional outcomes, were assessed. Clinical brain MRIs obtained at the time of the stroke underwent quantification of WMH using a fully automated algorithm. The pipeline incorporated automated brain extraction, intensity normalization, and WMH segmentation. RESULTS: A total of 1,601 acute ischemic strokes with documented 90-day mRS were identified, including 353 (22%) with LVO. Among those strokes, WMH volume was available in 1,285 (80.3%) who had a brain MRI suitable for WMH quantification. Increasing WMH volume from 0 to 4 mL, age, female gender, a number of stroke risk factors, presence of LVO, and higher NIHSS at presentation all decreased the odds for a favorable outcome. Increasing WMH above 4 mL, however, was not associated with decreasing odds of favorable outcome. While WMH volume was associated with functional outcome in non-LVO stroke (p = 0.0009), this association between WMH and functional status was not statistically significant in the complete case multivariable model of LVO stroke (p = 0.0637). CONCLUSION: The burden of WMH has effects on 90-day functional outcome after LVO and non-LVO strokes. Particularly, increases from no measurable WMH to 4 mL of WMH correlate strongly with the outcome. Whether this relationship of increasing WMH to worse outcome is more pronounced in non-LVO than LVO strokes deserves additional investigation.

Matrix Gla protein polymorphism rs1800801 associates with recurrence of ischemic stroke.

The MGP single nucleotide polymorphism (SNP) rs1800801 has previously been associated with recurrent ischemic stroke in a Spanish cohort. Here, we tested for association of this SNP with ischemic stroke recurrence in a North American Caucasian cohort. Acute ischemic stroke patients admitted between 10/2009 and 12/2016 at three hospitals within a large healthcare system in the northeastern United States that were enrolled in a healthcare system-wide exome sequencing program were retrospectively reviewed. Patients with recurrent stroke within 1 year after index event were compared to those without recurrence. Of 9,348 suspected acute ischemic strokes admitted between 10/2009 and 12/2016, 1,727 (18.5%) enrolled in the exome-sequencing program. Among those, 1,068 patients had exome sequencing completed and were eligible for inclusion. Recurrent stroke within the first year of stroke was observed in 79 patients (7.4%). In multivariable analysis, stroke prior to the index stroke (OR 9.694, 95% CI 5.793-16.224, p ≤ 0.001), pro-coagulant status (OR = 3.563, 95% CI 1.504-8.443, p = 0.004) and the AA genotype of SNP rs1800801 (OR = 2.408, 95% CI 1.079-4.389, p = 0.004) were independently associated with recurrent stroke within the first year. The AA genotype of the MGP SNP rs1800801 is associated with recurrence within the first year after ischemic stroke in North American Caucasians. Study of stroke subtypes and additional populations will be required to determine if incorporation of allelic status at this SNP into current risk scores improves prediction of recurrent ischemic stroke.

Transforaminal Endoscopic Approach for Large-Sample Tumor Biopsy using Beveled Working Channel for Core Technique: A Technical Note.

BACKGROUND: Identifying the histopathological diagnosis of a spinal tumor is the necessary step prior to pursuing subsequent treatment. Both minimally invasive and open spinal procedures have been described as useful methods of obtaining tumor tissue for diagnosis but differ by their limitations. Minimally invasive techniques, such as computed tomography-guided biopsies, can expose the patient to radiation, and the tissue obtained may be nondiagnostic. Tubular and open procedures require collateral soft-tissue damage and may require bony removal leading to iatrogenic injury. Endoscopic approaches to the spine can be employed to avoid treatment delay in diagnosis, decrease length of stay, and provide adequate tissue for diagnosis. METHODS: We describe the surgical planning, tumor localization, and transforaminal endoscopic approach for tissue diagnosis of a lumbar spinal mass in a patient with a known history of Hodgkin lymphoma and non-Hodgkin lymphoma after a nondiagnostic computed tomography- guided biopsy. Final histopathological diagnosis of the lumbar spinal mass was consistent with large B-cell non-Hodgkin lymphoma. CONCLUSIONS: We demonstrate the application of an endoscopic transforaminal approach in spine oncology. We also describe our technique on how we use a beveled working channel to obtain a large tissue core sample for definitive diagnosis.

Endovascular Treatment of Traumatic Transection of the Vertebral Artery Caused by Penetrating Injury to the Oropharynx in a Pediatric Patient.

BACKGROUND: Pediatric isolated penetrating traumatic vertebral artery injuries require urgent multidisciplinary management as they may lead to potentially fatal posterior circulation ischemia. CASE DESCRIPTION: We present a 19-month-old patient with an isolated penetrating vertebral artery injuries at the V2 segment of the right vertebral artery and report our strategy for her endovascular treatment which involved simultaneous coil embolization and foreign body removal. CONCLUSION: Endovascular treatment can be considered first line treatment of oral penetrating injuries to the vertebral artery, where the penetrating object has an anterior to posterior trajectory.

Risk Factors for Acute Ischemic Stroke Caused by Anterior Large Vessel Occlusion.

Background and Purpose- Accurate prediction of acute ischemic stroke (AIS) caused by anterior large vessel occlusion (LVO) that is amendable to mechanical thrombectomy remains a challenge. We developed and validated a prediction model for anterior circulation LVO stroke using past medical history elements present on admission and neurological examination. Methods- We retrospectively reviewed AIS patients admitted between 2009 and 2017 to 3 hospitals within a large healthcare system in the United States. Patients with occlusions of the internal carotid artery or M1 or M2 segments of the middle cerebral artery were randomly split into 2/3 derivation and 1/3 validation cohorts for development of an anterior circulation LVO prediction model and score that was further curtailed for potential use in the prehospital setting. Results- A total of 1654 AIS were reviewed, including 248 (15%) with proximal anterior circulation LVO AIS. In the derivation cohort, National Institutes of Health Stroke Scale score at the time of cerebrovascular imaging, current smoking status, type 2 diabetes mellitus, extracranial carotid, and intracranial atherosclerotic stenosis was significantly associated with anterior circulation LVO stroke. The prehospital score was curtailed to National Institutes of Health Stroke Scale score, current smoking status, and type 2 diabetes mellitus. The areas under the curve for the prediction model, prehospital score, and National Institutes of Health Stroke Scale score alone were 0.796, 0.757, and 0.725 for the derivation cohort and 0.770, 0.689, and 0.665 for the validation cohort, respectively. The Youden index J was 0.46 for a score of >6 with 84.7% sensitivity and 62.0% specificity for the prediction model. Conclusions- Previously reported LVO stroke prediction scores focus solely on elements of the neurological examination. In addition to stroke severity, smoking, diabetes mellitus, extracranial carotid, and intracranial atherosclerotic stenosis were associated with anterior circulation LVO AIS. Although atherosclerotic stenosis may not be known until imaging is obtained, smoking and diabetes mellitus history can be readily obtained in the field and represent important elements of the prehospital score supplementing National Institutes of Health Stroke Scale score.

A novel inhibitor of active protein kinase G attenuates chronic inflammatory and osteoarthritic pain.

Activating PKG-1α induces a long-term hyperexcitability (LTH) in nociceptive neurons. Since the LTH correlates directly with chronic pain in many animal models, we tested the hypothesis that inhibiting PKG-1α would attenuate LTH-mediated pain. We first synthesized and characterized compound N46 (N-((3R,4R)-4-(4-(2-fluoro-3-methoxy-6-propoxybenzoyl)benzamido)pyrrolidin-3-yl)-1H-indazole-5-carboxamide). N46 inhibits PKG-1α with an IC50 of 7.5 nmol, was highly selective when tested against a panel of 274 kinases, and tissue distribution studies indicate that it does not enter the CNS. To evaluate its antinociceptive potential, we used 2 animal models in which the pain involves both activated PKG-1α and LTH. Injecting complete Freund's adjuvant (CFA) into the rat hind paw causes a thermal hyperalgesia that was significantly attenuated 24 hours after a single intravenous injection of N46. Next, we used a rat model of osteoarthritic knee joint pain and found that a single intra-articular injection of N46 alleviated the pain 14 days after the pain was established and the relief lasted for 7 days. Thermal hyperalgesia and osteoarthritic pain are also associated with the activation of the capsaicin-activated transient receptor protein vanilloid-1 (TRPV1) channel. We show that capsaicin activates PKG-1α in nerves and that a subcutaneous delivery of N46 attenuated the mechanical and thermal hypersensitivity elicited by exposure to capsaicin. Thus, PKG-1α appears to be downstream of the transient receptor protein vanilloid-1. Our studies provide proof of concept in animal models that a PKG-1α antagonist has a powerful antinociceptive effect on persistent, already existing inflammatory pain. They further suggest that N46 is a valid chemotype for the further development of such antagonists.