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Yuan C, Xia P, Duan W, Wang J, Guan J, Du Y, Zhang C, Liu Z, Wang K, Wang Z, Wang X, Wu H, Chen Z, Jian F. Long-Term Impairment of the Blood-Spinal Cord Barrier in Patients With Post-Traumatic Syringomyelia and its Effect on Prognosis. Spine (Phila Pa 1976) 2024; 49:E62-E71. [PMID: 38014747 DOI: 10.1097/brs.0000000000004884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 11/05/2023] [Indexed: 11/29/2023]
Abstract
STUDY DESIGN Cohort study. OBJECTIVE The aim of this study was to explore the association between blood-spinal cord barrier (BSCB) markers and other factors associated with an unfavorable outcome among patients with post-traumatic syringomyelia (PTS) who achieved successful intradural adhesion lysis (IAL). SUMMARY OF BACKGROUND DATA Only approximately half of PTS patients receiving IAL have a favorable outcome. PATIENTS AND METHODS Forty-six consecutive patients with PTS and 19 controls (CTRL) were enrolled. All PTS patients underwent physical and neurological examinations and spinal magnetic resonance imaging before and 3 to 12 months after IAL. All patients underwent myelography before surgery. BSCB disruption was detected by increased intrathecal and serum concentrations of albumin, immunoglobulin (Ig)G, IgA, and IgM. A multivariable analysis was performed with a logistic regression model to identify factors associated with unfavorable outcomes. Receiver operating characteristic curves were calculated to investigate the diagnostic value of biomarkers. RESULTS The ages and general health of the PTS and CTRL groups did not differ significantly. QAlb, IGAQ, IGGQ, and IGMQ was significantly higher in PTS patients than in controls ( P =<0.001). The degree of intradural adhesion was significantly higher in the unfavorable outcome group than in the favorable outcome group ( P <0.0001). QAlb, immunoglobulin (Ig)AQ, IGGQ, and IGMQ was significantly correlated with clinical status ( R =-0.38, P <0.01; R =-0.47, P =0.03; R =-0.56, P =0.01; R =-0.43, P =0.05, respectively). Higher QAlb before surgery (odds ratio=2.66; 95% CI: 1.134-6.248) was significantly associated with an unfavorable outcome. The receiver operating characteristic curve analysis demonstrated a cutoff for QAlb higher than 10.62 with a specificity of 100% and sensitivity of 96.3%. CONCLUSION This study is the first to detect increased permeability and BSCB disruption in PTS patients. QAlb>10.62 was significantly associated with unfavorable clinical outcomes following intradural decompression. LEVEL OF EVIDENCE Level III-prognostic.
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Affiliation(s)
- Chenghua Yuan
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Pingchuan Xia
- Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Wanru Duan
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Jiachen Wang
- Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Jian Guan
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Yueqi Du
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Can Zhang
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Zhenlei Liu
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Kai Wang
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Zuowei Wang
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Xingwen Wang
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Hao Wu
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Zan Chen
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Fengzeng Jian
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
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Xia P, Lv H, Yuan C, Duan W, Wang J, Guan J, Du Y, Zhang C, Liu Z, Wang K, Wang Z, Wang X, Wu H, Chen Z, Jian F. Role of Preoperative Albumin Quotient in Surgical Planning for Posttraumatic Syringomyelia: A Comparative Cohort Study. Neurospine 2024; 21:212-222. [PMID: 38317552 PMCID: PMC10992642 DOI: 10.14245/ns.2347152.576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 12/13/2023] [Accepted: 12/15/2023] [Indexed: 02/07/2024] Open
Abstract
OBJECTIVE Surgical procedures for patients with posttraumatic syringomyelia (PTS) remain controversial. Until now, there have been no effective quantitative evaluation methods to assist in selecting appropriate surgical plans before surgery. METHODS We consecutively enrolled PTS patients (arachnoid lysis group, n = 42; shunting group, n = 14) from 2003 to 2023. Additionally, 19 intrathecal anesthesia patients were included in the control group. All patients with PTS underwent physical and neurological examinations and spinal magnetic resonance imaging preoperatively, 3-12 months postoperatively and during the last follow-up. Preoperative lumbar puncture was performed and blood-spinal cord barrier disruption was detected by quotient of albumin (Qalb, cerebrospinal fluid/serum). RESULTS The ages (p = 0.324) and sex (p = 0.065) of the PTS and control groups did not differ significantly. There were also no significant differences in age (p = 0.216), routine blood data and prognosis (p = 0.399) between the arachnoid lysis and shunting groups. But the QAlb level of PTS patients was significantly higher than that of the control group (p < 0.001), and the shunting group had a significantly higher QAlb (p < 0.001) than the arachnoid lysis group. A high preoperative QAlb (odds ratio, 1.091; 95% confidence interval, 1.004-1.187; p = 0.041) was identified as the predictive factor for the shunting procedure, with the receiver operating characteristic curve showing 100% specificity and 80.95% sensitivity for patients with a QAlb > 12.67. CONCLUSION Preoperative QAlb is a significant predictive factor for the types of surgery. For PTS patients with a QAlb > 12.67, shunting represents the final recourse, necessitating the exploration and development of novel treatments for these patients.
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Affiliation(s)
- Pingchuan Xia
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Houyuan Lv
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Chenghua Yuan
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Wanru Duan
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | | | - Jian Guan
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Yueqi Du
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Can Zhang
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Zhenlei Liu
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Kai Wang
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Zuowei Wang
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Xingwen Wang
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Hao Wu
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Zan Chen
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
| | - Fengzeng Jian
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
- Spine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
- National Center for Neurological Disorders, Beijing, China
- Lab of Spinal Cord Injury and Functional Reconstruction, China International Neuroscience Institute (CHINA-INI), Beijing, China
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Pukale DD, Adkins-Travis K, Aryal SR, Shriver LP, Patti GJ, Leipzig ND. Investigating post-traumatic syringomyelia and local fluid osmoregulation via a rat model. Fluids Barriers CNS 2024; 21:19. [PMID: 38409031 PMCID: PMC10895764 DOI: 10.1186/s12987-024-00514-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 01/25/2024] [Indexed: 02/28/2024] Open
Abstract
BACKGROUND Syringomyelia (SM) is characterized by the development of fluid-filled cavities, referred to as syrinxes, within the spinal cord tissue. The molecular etiology of SM post-spinal cord injury (SCI) is not well understood and only invasive surgical based treatments are available to treat SM clinically. This study builds upon our previous omics studies and in vitro cellular investigations to further understand local fluid osmoregulation in post-traumatic SM (PTSM) to highlight important pathways for future molecular interventions. METHODS A rat PTSM model consisting of a laminectomy at the C7 to T1 level followed by a parenchymal injection of 2 μL quisqualic acid (QA) and an injection of 5 μL kaolin in the subarachnoid space was utilized 6 weeks after initial surgery, parenchymal fluid and cerebrospinal fluid (CSF) were collected, and the osmolality of fluids were analyzed. Immunohistochemistry (IHC), metabolomics analysis using LC-MS, and mass spectrometry-based imaging (MSI) were performed on injured and laminectomy-only control spinal cords. RESULTS We demonstrated that the osmolality of the local parenchymal fluid encompassing syrinxes was higher compared to control spinal cords after laminectomy, indicating a local osmotic imbalance due to SM injury. Moreover, we also found that parenchymal fluid is more hypertonic than CSF, indicating establishment of a local osmotic gradient in the PTSM injured spinal cord (syrinx site) forcing fluid into the spinal cord parenchyma to form and/or expand syrinxes. IHC results demonstrated upregulation of betaine, ions, water channels/transporters, and enzymes (BGT1, AQP1, AQP4, CHDH) at the syrinx site as compared to caudal and rostral sites to the injury, implying extensive local osmoregulation activities at the syrinx site. Further, metabolomics analysis corroborated alterations in osmolality at the syrinx site by upregulation of small molecule osmolytes including betaine, carnitine, glycerophosphocholine, arginine, creatine, guanidinoacetate, and spermidine. CONCLUSIONS In summary, PTSM results in local osmotic disturbance that propagates at 6 weeks following initial injury. This coincides with and may contribute to syrinx formation/expansion.
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Affiliation(s)
- Dipak D Pukale
- Department of Chemical, Biomolecular, and Corrosion Engineering, The University of Akron, Akron, OH, 44325, USA
| | - Kayla Adkins-Travis
- Departments of Chemistry and Medicine, Center for Proteomics, Metabolomics, and Isotope Tracing, Washington University in St. Louis, St. Louis, MO, 63130, USA
| | - Siddhartha R Aryal
- Department of Biomedical Engineering, The University of Akron, Akron, OH, 44325, USA
| | - Leah P Shriver
- Departments of Chemistry and Medicine, Center for Proteomics, Metabolomics, and Isotope Tracing, Washington University in St. Louis, St. Louis, MO, 63130, USA
| | - Gary J Patti
- Departments of Chemistry and Medicine, Center for Proteomics, Metabolomics, and Isotope Tracing, Washington University in St. Louis, St. Louis, MO, 63130, USA
| | - Nic D Leipzig
- Department of Chemical, Biomolecular, and Corrosion Engineering, The University of Akron, Akron, OH, 44325, USA.
- Department of Biomedical Engineering, The University of Akron, Akron, OH, 44325, USA.
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Lu C, Wu X, Wang X, Xiao Z, Ma L, Dai J, Jian F. Single-cell transcriptomics reveals ependymal subtypes related to cytoskeleton dynamics as the core driver of syringomyelia pathological development. iScience 2023; 26:106850. [PMID: 37275526 PMCID: PMC10232665 DOI: 10.1016/j.isci.2023.106850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 03/05/2023] [Accepted: 05/04/2023] [Indexed: 06/07/2023] Open
Abstract
Syringomyelia is a common clinical lesion associated with cerebrospinal fluid flow abnormalities. By a reversible model with chronic extradural compression to mimic human canalicular syringomyelia, we explored the spatiotemporal pathological alterations during syrinx development. The most dynamic alterations were observed in ependymal cells (EPCs), oligodendrocyte lineage, and microglia, as a response to neuroinflammation. Among different cell types, EPC subtypes experienced obvious dynamic alterations, which were accompanied by ultrastructural changes involving the ependymal cytoskeleton, cilia, and dynamic injury in parenchyma primarily around the central canal, corresponding to the single-cell transcripts. After effective decompression, the syrinx resolved with the recovery of pathological damage and overall neurological function, implying that for syringomyelia in the early stage, there was still endogenous repair potential coexisting with immune microenvironment imbalance. Ependymal remodeling and cilia restoration might be important for better resolution of syringomyelia and parenchymal injury recovery.
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Affiliation(s)
- Chunli Lu
- Division of Spine, Department of Neurosurgery, Xuanwu Hospital, Capital Medical University (CCMU), Beijing, China
- Neurospine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, CCMU, Beijing, China
- Lab of Spinal Cord Injury and Function Reconstruction, CHINA-INI, Beijing, China
- National Center for Neurological Disorders, Beijing, China
| | - Xianming Wu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Xinyu Wang
- Division of Spine, Department of Neurosurgery, Xuanwu Hospital, Capital Medical University (CCMU), Beijing, China
- Neurospine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, CCMU, Beijing, China
- Lab of Spinal Cord Injury and Function Reconstruction, CHINA-INI, Beijing, China
- National Center for Neurological Disorders, Beijing, China
| | - Zhifeng Xiao
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Longbing Ma
- Division of Spine, Department of Neurosurgery, Xuanwu Hospital, Capital Medical University (CCMU), Beijing, China
- Neurospine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, CCMU, Beijing, China
- Lab of Spinal Cord Injury and Function Reconstruction, CHINA-INI, Beijing, China
- National Center for Neurological Disorders, Beijing, China
| | - Jianwu Dai
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Fengzeng Jian
- Division of Spine, Department of Neurosurgery, Xuanwu Hospital, Capital Medical University (CCMU), Beijing, China
- Neurospine Center, China International Neuroscience Institute (CHINA-INI), Beijing, China
- Research Center of Spine and Spinal Cord, Beijing Institute of Brain Disorders, CCMU, Beijing, China
- Lab of Spinal Cord Injury and Function Reconstruction, CHINA-INI, Beijing, China
- National Center for Neurological Disorders, Beijing, China
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Pukale DD, Lazarenko D, Aryal SR, Khabaz F, Shriver LP, Leipzig ND. Osmotic Contribution of Synthesized Betaine by Choline Dehydrogenase Using In Vivo and In Vitro Models of Post-traumatic Syringomyelia. Cell Mol Bioeng 2023; 16:41-54. [PMID: 36660584 PMCID: PMC9842837 DOI: 10.1007/s12195-022-00749-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 10/27/2022] [Indexed: 11/28/2022] Open
Abstract
Introduction Syringomyelia (SM) is a debilitating spinal cord disorder in which a cyst, or syrinx, forms in the spinal cord parenchyma due to congenital and acquired causes. Over time syrinxes expand and elongate, which leads to compressing the neural tissues and a mild to severe range of symptoms. In prior omics studies, significant upregulation of betaine and its synthesis enzyme choline dehydrogenase (CHDH) were reported during syrinx formation/expansion in SM injured spinal cords, but the role of betaine regulation in SM etiology remains unclear. Considering betaine's known osmoprotectant role in biological systems, along with antioxidant and methyl donor activities, this study aimed to better understand osmotic contributions of synthesized betaine by CHDH in response to SM injuries in the spinal cord. Methods A post-traumatic SM (PTSM) rat model and in vitro cellular models using rat astrocytes and HepG2 liver cells were utilized to investigate the role of betaine synthesis by CHDH. Additionally, the osmotic contributions of betaine were evaluated using a combination of experimental as well as simulation approaches. Results In the PTSM injured spinal cord CHDH expression was observed in cells surrounding syrinxes. We next found that rat astrocytes and HepG2 cells were capable of synthesizing betaine via CHDH under osmotic stress in vitro to maintain osmoregulation. Finally, our experimental and simulation approaches showed that betaine was capable of directly increasing meaningful osmotic pressure. Conclusions The findings from this study demonstrate new evidence that CHDH activity in the spinal cord provides locally synthesized betaine for osmoregulation in SM pathophysiology. Supplementary Information The online version of this article contains supplementary material available 10.1007/s12195-022-00749-5.
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Affiliation(s)
- Dipak D. Pukale
- Department of Chemical, Biomolecular, and Corrosion Engineering, University of Akron, Akron, OH 44325 USA
| | - Daria Lazarenko
- School of Polymer Science and Polymer Engineering, The University of Akron, Akron, OH 44325 USA
| | - Siddhartha R. Aryal
- Department of Biomedical Engineering, The University of Akron, Akron, OH 44325 USA
| | - Fardin Khabaz
- Department of Chemical, Biomolecular, and Corrosion Engineering, University of Akron, Akron, OH 44325 USA
- School of Polymer Science and Polymer Engineering, The University of Akron, Akron, OH 44325 USA
| | - Leah P. Shriver
- Department of Chemistry, Washington University, Saint Louis, MO 63130 USA
- Department of Medicine, Washington University, Saint Louis, MO 63130 USA
- Center for Metabolomics and Isotope Tracing, Washington University, Saint Louis, MO 63130 USA
| | - Nic D. Leipzig
- Department of Chemical, Biomolecular, and Corrosion Engineering, University of Akron, Akron, OH 44325 USA
- Department of Biomedical Engineering, The University of Akron, Akron, OH 44325 USA
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Jin P, Munson JM. Fluids and flows in brain cancer and neurological disorders. WIREs Mech Dis 2023; 15:e1582. [PMID: 36000149 PMCID: PMC9869390 DOI: 10.1002/wsbm.1582] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 06/21/2022] [Accepted: 06/27/2022] [Indexed: 01/31/2023]
Abstract
Interstitial fluid (IF) and cerebrospinal fluid (CSF) are an integral part of the brain, serving to cushion and protect the brain parenchymal cells against damage and aid in their function. The brain IF contains various ions, nutrients, waste products, peptides, hormones, and neurotransmitters. IF moves primarily by pressure-dependent bulk flow through brain parenchyma, draining into the ventricular CSF. The brain ventricles and subarachnoid spaces are filled with CSF which circulates through the perivascular spaces. It also flows into the IF space regulated, in part, by aquaporin channels, removing waste solutes through a process of IF-CSF mixing. During disease development, the composition, flow, and volume of these fluids changes and can lead to brain cell dysfunction. With the improvement of imaging technology and the help of genomic profiling, more information has been and can be obtained from brain fluids; however, the role of CSF and IF in brain cancer and neurobiological disease is still limited. Here we outline recent advances of our knowledge of brain fluid flow in cancer and neurodegenerative disease based on our understanding of its dynamics and composition. This article is categorized under: Cancer > Biomedical Engineering Neurological Diseases > Biomedical Engineering.
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Affiliation(s)
- Peng Jin
- Fralin Biomedical Research Institute, Department of Biomedical Engineering and Mechanics Virginia Polytechnic Institute and State University Roanoke Virginia USA
| | - Jennifer M. Munson
- Fralin Biomedical Research Institute, Department of Biomedical Engineering and Mechanics Virginia Polytechnic Institute and State University Roanoke Virginia USA
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Seiner A, Burla GKR, Shrestha D, Bowen M, Horvath JD, Martin BA. Investigation of Human Intrathecal Solute Transport Dynamics Using a Novel in vitro Cerebrospinal Fluid System Analog. FRONTIERS IN NEUROIMAGING 2022; 1:879098. [PMID: 37555174 PMCID: PMC10406265 DOI: 10.3389/fnimg.2022.879098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 05/24/2022] [Indexed: 08/10/2023]
Abstract
BACKGROUND Understanding the relationship between cerebrospinal fluid (CSF) dynamics and intrathecal drug delivery (ITDD) injection parameters is essential to improve treatment of central nervous system (CNS) disorders. METHODS An anatomically detailed in vitro model of the complete CSF system was constructed. Patient-specific cardiac- and respiratory-induced CSF oscillations were input to the model in the subarachnoid space and within the ventricles. CSF production was input at the lateral ventricles and CSF absorption at the superior sagittal sinus. A model small molecule simulated drug product containing fluorescein was imaged within the system over a period of 3-h post-lumbar ITDD injections and used to quantify the impact of (a) bolus injection volume and rate, (b) post-injection flush volume, rate, and timing, (c) injection location, and (d) type of injection device. For each experiment, neuraxial distribution of fluorescein in terms of spatial temporal concentration, area-under-the-curve (AUC), and percent of injected dose (%ID) to the brain was quantified at a time point 3-h post-injection. RESULTS For all experiments conducted with ITDD administration in the lumbar spine, %ID to the brain did not exceed 11.6% at a time point 3-h post-injection. Addition of a 12 mL flush slightly increased solute transport to the brain up to +3.9%ID compared to without a flush (p < 0.01). Implantation of a lumbar catheter with the tip at an equivalent location to the lumbar placed needle, but with rostral tip orientation, resulted in a small improvement of 1.5%ID to the brain (p < 0.05). An increase of bolus volume from 5 to 20 mL improved solute transport to the brain from 5.0 to 6.3%ID, but this improvement was not statistically significant. Increasing bolus injection rate from 5 to 13.3 mL/min lacked improvement of solute transport to the brain, with a value of 6.3 compared to 5.7%ID. CONCLUSION The in vitro modeling approach allowed precisely controlled and repeatable parametric investigation of ITDD injection protocols and devices. In combination, the results predict that parametric changes in lumbar spine ITDD-injection related parameters and devices can alter %ID to the brain and be tuned to optimize therapeutic benefit to CNS targets.
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Affiliation(s)
- Akari Seiner
- Department of Chemical and Biological Engineering, University of Idaho, Moscow, ID, United States
| | | | - Dev Shrestha
- Department of Chemical and Biological Engineering, University of Idaho, Moscow, ID, United States
| | - Mayumi Bowen
- Genentech, Inc., A Member of the Roche Group, South San Francisco, CA, United States
| | - Joshua D. Horvath
- Genentech, Inc., A Member of the Roche Group, South San Francisco, CA, United States
| | - Bryn A. Martin
- Department of Chemical and Biological Engineering, University of Idaho, Moscow, ID, United States
- Alcyone Therapeutics Inc., Lowell, MA, United States
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Pukale DD, Farrag M, Leipzig ND. Detection of locomotion deficit in a post-traumatic syringomyelia rat model using automated gait analysis technique. PLoS One 2021; 16:e0252559. [PMID: 34762669 PMCID: PMC8584658 DOI: 10.1371/journal.pone.0252559] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Accepted: 10/24/2021] [Indexed: 11/24/2022] Open
Abstract
Syringomyelia (SM) is a spinal cord disorder in which a cyst (syrinx) filled with fluid forms in the spinal cord post-injury/disease, in patients syrinx symptoms include loss of pain and temperature sensation or locomotion deficit. Currently, there are no small animal models and connected tools to help study the functional impacts of SM. The objective of this study was to determine the detectability of subtle locomotion deficits due to syrinx formation/expansion in post-traumatic syringomyelia (PTSM) rat model using the recently reported method of Gait Analysis Instrumentation, and Technology Optimized for Rodents (GAITOR) with Automated Gait Analysis Through Hues and Areas (AGATHA) technique. First videos of the rats were collected while walking in an arena (using GAITOR) followed by extracting meaningful locomotion information from collected videos using AGATHA protocol. PTSM injured rats demonstrated detectable locomotion deficits in terms of duty factor imbalance, paw placement accuracy, step contact width, stride length, and phase dispersion parameters compared to uninjured rats due to SM. We concluded that this technique could detect mild and subtle locomotion deficits associated with PTSM injury, which also in future work could be used further to monitor locomotion responses after different treatment strategies for SM.
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Affiliation(s)
- Dipak D. Pukale
- Department of Chemical, Biomolecular, and Corrosion Engineering, University of Akron, Akron, Ohio, United States of America
| | - Mahmoud Farrag
- Integrated Bioscience Program, University of Akron, Akron, Ohio, United States of America
| | - Nic D. Leipzig
- Department of Chemical, Biomolecular, and Corrosion Engineering, University of Akron, Akron, Ohio, United States of America
- Integrated Bioscience Program, University of Akron, Akron, Ohio, United States of America
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Pukale DD, Farrag M, Gudneppanavar R, Baumann HJ, Konopka M, Shriver LP, Leipzig ND. Osmoregulatory Role of Betaine and Betaine/γ-Aminobutyric Acid Transporter 1 in Post-Traumatic Syringomyelia. ACS Chem Neurosci 2021; 12:3567-3578. [PMID: 34550670 DOI: 10.1021/acschemneuro.1c00056] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Syringomyelia (SM) is primarily characterized by the formation of a fluid-filled cyst that forms in the parenchyma of the spinal cord following injury or other pathology. Recent omics studies in animal models have identified dysregulation of solute carriers, channels, transporters, and small molecules associated with osmolyte regulation during syrinx formation/expansion in the spinal cord. However, their connections to syringomyelia etiology are poorly understood. In this study, the biological functions of the potent osmolyte betaine and its associated solute carrier betaine/γ-aminobutyric acid (GABA) transporter 1 (BGT1) were studied in SM. First, a rat post-traumatic SM model was used to demonstrate that the BGT1 was primarily expressed in astrocytes in the vicinity of syrinxes. In an in vitro system, we found that astrocytes uptake betaine through BGT1 to regulate cell size under hypertonic conditions. Treatment with BGT1 inhibitors, especially NNC 05-2090, demonstrated midhigh micromolar range potency in vitro that reversed the osmoprotective effects of betaine. Finally, the specificity of these BGT1 inhibitors in the CNS was demonstrated in vivo, suggesting feasibility for targeting betaine transport in SM. In summary, these data provide an enhanced understanding of the role of betaine and its associated solute carrier BGT1 in cell osmoregulation and implicates the active role of betaine and BGT1 in syringomyelia progression.
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Affiliation(s)
- Dipak D. Pukale
- Department of Chemical, Biomolecular, and Corrosion Engineering, University of Akron, Akron, Ohio 44325, United States
| | - Mahmoud Farrag
- Integrated Biosciences Program, University of Akron, Akron, Ohio 44325, United States
| | | | - Hannah J. Baumann
- Department of Chemistry, University of Akron, Akron, Ohio 44325, United States
| | - Michael Konopka
- Department of Chemistry, University of Akron, Akron, Ohio 44325, United States
| | - Leah P. Shriver
- Integrated Biosciences Program, University of Akron, Akron, Ohio 44325, United States
- Department of Chemistry, University of Akron, Akron, Ohio 44325, United States
| | - Nic D. Leipzig
- Department of Chemical, Biomolecular, and Corrosion Engineering, University of Akron, Akron, Ohio 44325, United States
- Integrated Biosciences Program, University of Akron, Akron, Ohio 44325, United States
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Chronic extradural compression of spinal cord leads to syringomyelia in rat model. Fluids Barriers CNS 2020; 17:50. [PMID: 32736591 PMCID: PMC7393857 DOI: 10.1186/s12987-020-00213-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Accepted: 07/20/2020] [Indexed: 11/23/2022] Open
Abstract
Background Syringomyelia is a common spinal cord lesion. However, whether CSF blockage is linked to the formation and enlargement of syringomyelia is still controversial. The current model of syringomyelia needs modification to more closely mimic the clinical situation. Methods We placed cotton strips under the T13 lamina of 40 8-week-old rats and blocked CSF flow by extradural compression. After 4 and 8 weeks, MRI was performed to evaluate the morphology of syringomyelia and the ratio of spinal cord diameter to syrinx diameter calculated. Locomotor function was evaluated weekly. Spinal cord sections, staining and immunohistochemistry were performed 8 weeks after surgery, the ratio of the central canal to the spinal cord area was calculated, and ependymal cells were counted. In another experiment, we performed decompression surgery for 8 rats with induced syringomyelia at the 8th week after surgery. During the surgery, the cotton strip was completely removed without damaging the dura mater. Then, the rats received MRI imaging during the following weeks and were sacrificed for pathological examination at the end of the experiment. Results Syringomyelia formed in 82.5% (33/40) of rats at the 8-week follow-up. The Basso, Beattie and Bresnahan (BBB) scores of rats in the experimental group decreased from 21.0±0.0 to 18.0 ±3.9 in the first week after operation but returned to normal in later weeks. The BBB score indicated that the locomotor deficit caused by compression is temporary and can spontaneously recover. MRI showed that the syrinx is located in the center of the spinal cord, which is very similar to the most common syringomyelia in humans. The ratio of the central canal to the spinal cord area reached (2.9 ± 2.0) × 10−2, while that of the sham group was (5.4 ± 1.5) × 10−4. The number of ependymal cells lining the central canal was significantly increased (101.9 ± 39.6 vs 54.5 ± 3.4). There was no syrinx or proliferative inflammatory cells in the spinal cord parenchyma. After decompression, the syringomyelia size decreased in 50% (4/8) of the rats and increased in another 50% (4/8). Conclusion Extradural blockade of CSF flow can induce syringomyelia in rats. Temporary locomotor deficit occurred in some rats. This reproducible rat model of syringomyelia, which mimics syringomyelia in humans, can provide a good model for the study of disease mechanisms and therapies.
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Mohrman AE, Farrag M, Huang H, Ossowski S, Haft S, Shriver LP, Leipzig ND. Spinal Cord Transcriptomic and Metabolomic Analysis after Excitotoxic Injection Injury Model of Syringomyelia. J Neurotrauma 2017; 34:720-733. [DOI: 10.1089/neu.2015.4341] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Ashley E. Mohrman
- Department of Chemical and Biomolecular Engineering, University of Akron, Akron, Ohio
| | - Mahmoud Farrag
- Department of Integrated Biosciences Program, University of Akron, Akron, Ohio
| | - He Huang
- Department of Chemistry, University of Akron, Akron, Ohio
| | - Stephan Ossowski
- Centre for Genomic Regulation, The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Stephanie Haft
- Langley Porter Psychiatric Institute, University of California San Francisco, San Francisco, California
| | | | - Nic D. Leipzig
- Department of Chemical and Biomolecular Engineering, University of Akron, Akron, Ohio
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Najafi E, Stoodley MA, Bilston LE, Hemley SJ. Inwardly rectifying potassium channel 4.1 expression in post-traumatic syringomyelia. Neuroscience 2016; 317:23-35. [PMID: 26768400 DOI: 10.1016/j.neuroscience.2016.01.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Revised: 12/23/2015] [Accepted: 01/02/2016] [Indexed: 10/22/2022]
Abstract
Post-traumatic syringomyelia (PTS) is a serious neurological disorder characterized by fluid filled cavities that develop in the spinal cord. PTS is thought to be caused by an imbalance between fluid inflow and outflow in the spinal cord, but the underlying mechanisms are unknown. The ion channel Kir4.1 plays an important role in the uptake of K(+) ions from the extracellular space and release of K(+) ions into the microvasculature, generating an osmotic gradient that drives water movement. Changes in Kir4.1 expression may contribute to disturbances in K(+) homeostasis and subsequently fluid imbalance. Here we investigated whether changes in Kir4.1 protein expression occur in PTS. Western blotting and immunohistochemistry were used to evaluate Kir4.1 and glial fibrillary acidic protein (GFAP) expression in a rodent model of PTS at 3 days, 1, 6 or 12 weeks post-surgery. In Western blotting experiments, Kir4.1 expression increased 1 week post-surgery at the level of the cavity. Immunohistochemical analysis examined changes in the spinal parenchyma directly in contact with the syrinx cavity. In these experiments, there was a significant decrease in Kir4.1 expression in PTS animals compared to controls at 3 days and 6 weeks post-surgery, while an up-regulation of GFAP in PTS animals was observed at 1 and 12 weeks. This suggests that while overall Kir4.1 expression is unchanged at these time-points, there are many astrocytes surrounding the syrinx cavity that are not expressing Kir4.1. The results demonstrate a disturbance in the removal of K(+) ions in tissue surrounding a post-traumatic syrinx cavity. It is possible this contributes to water accumulation in the injured spinal cord leading to syrinx formation or exacerbation of the underlying pathology.
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Affiliation(s)
- E Najafi
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia.
| | - M A Stoodley
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia.
| | - L E Bilston
- Neuroscience Research Australia, Sydney, NSW, Australia; Prince of Wales Clinical School, University of New South Wales, Randwick, NSW, Australia.
| | - S J Hemley
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia.
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Pulse wave myelopathy: An update of an hypothesis highlighting the similarities between syringomyelia and normal pressure hydrocephalus. Med Hypotheses 2015; 85:958-61. [PMID: 26362731 DOI: 10.1016/j.mehy.2015.08.028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 08/26/2015] [Indexed: 10/23/2022]
Abstract
Most hypotheses trying to explain the pathophysiology of idiopathic syringomyelia involve mechanisms whereby CSF is pumped against a pressure gradient, from the subarachnoid space into the cord parenchyma. On review, these theories have universally failed to explain the disease process. A few papers have suggested that the syrinx fluid may originate from the cord capillary bed itself. However, in these papers, the fluid is said to accumulate due to impaired fluid drainage out of the cord. Again, there is little evidence to substantiate this. This proffered hypothesis looks at the problem from the perspective that syringomyelia and normal pressure hydrocephalus are almost identical in their manifestations but only differ in their site of effect within the neuraxis. It is suggested that the primary trigger for syringomyelia is a reduction in the compliance of the veins draining the spinal cord. This reduces the efficiency of the pulse wave dampening, occurring within the cord parenchyma, increasing arteriolar and capillary pulse pressure. The increased capillary pulse pressure opens the blood-spinal cord barrier due to a direct effect upon the wall integrity and interstitial fluid accumulates due to an increased secretion rate. An increase in arteriolar pulse pressure increases the kinetic energy within the cord parenchyma and this disrupts the cytoarchitecture allowing the fluid to accumulate into small cystic regions in the cord. With time the cystic regions coalesce to form one large cavity which continues to increase in size due to the ongoing interstitial fluid secretion and the hyperdynamic cord vasculature.
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Aghayev K, Vrionis FD. Letter to the Editor: Syringomyelia. J Neurosurg Spine 2013; 18:664-5. [DOI: 10.3171/2012.12.spine121095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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