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Revista Brasileira de Anestesiologia 2010Due to the discomfort caused to patients, failure of subarachnoid blocks that happen occasionally even when properly conducted be the most capable professionals have... (Review)
Review
BACKGROUND AND OBJECTIVES
Due to the discomfort caused to patients, failure of subarachnoid blocks that happen occasionally even when properly conducted be the most capable professionals have been described since Bier. However, the concept of failure and especially identification of the causes vary. The objective of this report was to identify the causes of this discomfort through a systematic review of publications with a significant number of patients.
CONTENTS
The analysis was divided in three topics: anatomy and its variations; anesthetic agent, focusing on drug selection, its solutions, and additions to achieve the most appropriate result of the proposed surgery; and the dose, discussing concentration, volume, or gravimetric dose, to obtain the most adequate result regarding the intensity of the blockade and its duration.
CONCLUSIONS
Failures are more commonly secondary to technical factors: adequate anatomic assessment, judicious choice of the needle and puncture site, care when storing the drugs, dose adequacy, and baricity, besides proper patient positioning during and after the puncture, and they all should be adequate for the surgical objective.
Topics: Anesthesia, Spinal; Humans; Subarachnoid Space; Treatment Failure
PubMed: 20169268
DOI: 10.1016/s0034-7094(10)70011-8 -
Revue Medicale de Liege Sep 2020We report the case of a 28-year-old male admitted to the emergency department for generalized seizure. A brain computed tomography (CT) revealed a ruptured dermoid cyst...
We report the case of a 28-year-old male admitted to the emergency department for generalized seizure. A brain computed tomography (CT) revealed a ruptured dermoid cyst of the supra-tentorial stage (multiple drop-shaped fat structures were found in the subarachnoid space, basal cisterns and in ventricular system). An additional magnetic resonance imaging (MRI) was conducted to confirm the CT findings.
Topics: Adult; Dermoid Cyst; Humans; Magnetic Resonance Imaging; Male; Rupture, Spontaneous; Subarachnoid Space; Tomography, X-Ray Computed
PubMed: 32909404
DOI: No ID Found -
British Journal of Anaesthesia Jan 2004It has been suggested that obstetric epidurals lead to chronic adhesive arachnoiditis (CAA). CAA is a nebulous disease entity with much confusion over its... (Review)
Review
It has been suggested that obstetric epidurals lead to chronic adhesive arachnoiditis (CAA). CAA is a nebulous disease entity with much confusion over its symptomatology. This review outlines the pathological, clinical, and radiological features of the disease. The proposed diagnostic criteria for CAA are: back pain that increases on exertion, with or without leg pain; neurological abnormality on examination; and characteristic MRI findings. Using these criteria, there is evidence to show that epidural or subarachnoid placement of some contrast media, preservatives and possibly vasoconstrictors, may lead to CAA. No evidence was found that the preservative-free, low concentration bupivacaine with opioid mixtures or plain bupivacaine currently used in labour lead to CAA.
Topics: Anesthesia, Epidural; Anesthesia, Obstetrical; Arachnoiditis; Back Pain; Chronic Disease; Female; Humans; Peripheral Nerve Injuries; Pregnancy; Risk Factors; Tissue Adhesions
PubMed: 14665562
DOI: 10.1093/bja/aeh009 -
Developmental Cell Apr 2023The arachnoid barrier, a component of the blood-cerebrospinal fluid barrier (B-CSFB) in the meninges, is composed of epithelial-like, tight-junction-expressing cells....
The arachnoid barrier, a component of the blood-cerebrospinal fluid barrier (B-CSFB) in the meninges, is composed of epithelial-like, tight-junction-expressing cells. Unlike other central nervous system (CNS) barriers, its' developmental mechanisms and timing are largely unknown. Here, we show that mouse arachnoid barrier cell specification requires the repression of Wnt-β-catenin signaling and that constitutively active β-catenin can prevent its formation. We also show that the arachnoid barrier is functional prenatally and, in its absence, a small molecular weight tracer and the bacterium group B Streptococcus can cross into the CNS following peripheral injection. Acquisition of barrier properties prenatally coincides with the junctional localization of Claudin 11, and increased E-cadherin and maturation continues after birth, where postnatal expansion is marked by proliferation and re-organization of junctional domains. This work identifies fundamental mechanisms that drive arachnoid barrier formation, highlights arachnoid barrier fetal functions, and provides novel tools for future studies on CNS barrier development.
Topics: Mice; Animals; beta Catenin; Meninges; Arachnoid; Blood-Brain Barrier; Central Nervous System; Tight Junctions
PubMed: 36996816
DOI: 10.1016/j.devcel.2023.03.005 -
Nature Communications Sep 2023Meninges cover the surface of the brain and spinal cord and contribute to protection and immune surveillance of the central nervous system (CNS). How the meningeal...
Meninges cover the surface of the brain and spinal cord and contribute to protection and immune surveillance of the central nervous system (CNS). How the meningeal layers establish CNS compartments with different accessibility to immune cells and immune mediators is, however, not well understood. Here, using 2-photon imaging in female transgenic reporter mice, we describe VE-cadherin at intercellular junctions of arachnoid and pia mater cells that form the leptomeninges and border the subarachnoid space (SAS) filled with cerebrospinal fluid (CSF). VE-cadherin expression also marked a layer of Prox1 cells located within the arachnoid beneath and separate from E-cadherin arachnoid barrier cells. In vivo imaging of the spinal cord and brain in female VE-cadherin-GFP reporter mice allowed for direct observation of accessibility of CSF derived tracers and T cells into the SAS bordered by the arachnoid and pia mater during health and neuroinflammation, and detection of volume changes of the SAS during CNS pathology. Together, the findings identified VE-cadherin as an informative landmark for in vivo imaging of the leptomeninges that can be used to visualize the borders of the SAS and thus potential barrier properties of the leptomeninges in controlling access of immune mediators and immune cells into the CNS during health and neuroinflammation.
Topics: Female; Animals; Mice; Pia Mater; Neuroinflammatory Diseases; Central Nervous System; Arachnoid; Cadherins; Inflammation; Mice, Transgenic
PubMed: 37730744
DOI: 10.1038/s41467-023-41580-4 -
Fluids and Barriers of the CNS Dec 2022Cerebrospinal fluid (CSF) is an essential and critical component of the central nervous system (CNS). According to the concept of the "third circulation" originally... (Review)
Review
Cerebrospinal fluid (CSF) is an essential and critical component of the central nervous system (CNS). According to the concept of the "third circulation" originally proposed by Cushing, CSF is mainly produced by the choroid plexus and subsequently leaves the cerebral ventricles via the foramen of Magendie and Luschka. CSF then fills the subarachnoid space from whence it disperses to all parts of the CNS, including the forebrain and spinal cord. CSF provides buoyancy to the submerged brain, thus protecting it against mechanical injury. CSF is also transported via the glymphatic pathway to reach deep interstitial brain regions along perivascular channels; this CSF clearance pathway promotes transport of energy metabolites and signaling molecules, and the clearance of metabolic waste. In particular, CSF is now intensively studied as a carrier for the removal of proteins implicated in neurodegeneration, such as amyloid-β and tau. Despite this key function of CSF, there is little information about its production rate, the factors controlling CSF production, and the impact of diseases on CSF flux. Therefore, we consider it to be a matter of paramount importance to quantify better the rate of CSF production, thereby obtaining a better understanding of CSF dynamics. To this end, we now review the existing methods developed to measure CSF production, including invasive, noninvasive, direct, and indirect methods, and MRI-based techniques. Depending on the methodology, estimates of CSF production rates in a given species can extend over a ten-fold range. Throughout this review, we interrogate the technical details of CSF measurement methods and discuss the consequences of minor experimental modifications on estimates of production rate. Our aim is to highlight the gaps in our knowledge and inspire the development of more accurate, reproducible, and less invasive techniques for quantitation of CSF production.
Topics: Central Nervous System; Glymphatic System; Brain; Subarachnoid Space; Cerebral Ventricles; Cerebrospinal Fluid
PubMed: 36522656
DOI: 10.1186/s12987-022-00382-4 -
PloS One 2022This patient and public-involved systematic review originally focused on arachnoiditis, a supposedly rare "iatrogenic chronic meningitis" causing permanent neurologic... (Review)
Review
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.
Topics: Arachnoiditis; Biological Products; Humans; Iatrogenic Disease; Meningitis; Prospective Studies
PubMed: 36178925
DOI: 10.1371/journal.pone.0274634 -
British Medical Journal Aug 1978
Topics: Arachnoiditis; Humans; Metrizamide; Radiography; Spinal Cord Diseases; Spinal Puncture
PubMed: 698548
DOI: No ID Found -
BMC Neurology Apr 2021The physiological and pathological significance of the arachnoid membrane (AM) is still unknown. In this study, we investigated various characteristics of the AM,... (Observational Study)
Observational Study
BACKGROUND
The physiological and pathological significance of the arachnoid membrane (AM) is still unknown. In this study, we investigated various characteristics of the AM, focusing on the influence of inflammation and fibrosis.
METHODS
Small pieces of AM sample were obtained during neurosurgical procedures from 74 cases. The clinical and pathological characteristics of the hyperplastic AM group (≥ 50 μm) and the non-hyperplastic AM group (< 50 μm) were compared. Then, potential correlations between AM thickness and clinical characteristics were analyzed. Moreover, VEGFα, TGFβ, and TGFα levels were quantitated by real time PCR. Then, the potential correlations between AM thickness and these inflammatory or anti-inflammatory markers, and the influence of the original disease were calculated.
RESULTS
The median age of the patients in hyperplastic AM group was significantly older than that of the non-hyperplastic AM group. Moreover, the number of fibroblasts, CD68 cells, CD86 cells, and CD206 cells in the hyperplastic AM group was significantly higher than that in the non-hyperplastic AM group. The AM thickness was significantly correlated to age and number of fibroblasts, CD68 cells, CD86 cells, and CD206 cells. The thickness of the AM was significantly correlated to the messenger RNA expression levels of VEGFα (ρ = 0.337), and the VEGFα expression levels were significantly correlated with TGFβ and TNFα.
CONCLUSIONS
The AM hyperplasia was influenced by aging and could be a result of inflammation and fibrosis through cytokine secretion from the inflammatory cells and fibroblasts in the AM.
Topics: Adult; Aged; Aging; Arachnoid; Female; Fibrosis; Humans; Inflammation; Male; Middle Aged
PubMed: 33882882
DOI: 10.1186/s12883-021-02202-y -
Journal of Anatomy Aug 2020Traumatic brain injury (TBI) is a common injury modality affecting a diverse patient population. Axonal injury occurs when the brain experiences excessive deformation as...
Traumatic brain injury (TBI) is a common injury modality affecting a diverse patient population. Axonal injury occurs when the brain experiences excessive deformation as a result of head impact. Previous studies have shown that the arachnoid trabeculae (AT) in the subarachnoid space significantly influence the magnitude and distribution of brain deformation during impact. However, the quantity and spatial distribution of cranial AT in humans is unknown. Quantification of these microstructural features will improve understanding of force transfer during TBI, and may be a valuable dataset for microneurosurgical procedures. In this study, we quantify the spatial distribution of cranial AT in seven post-mortem human subjects. Optical coherence tomography (OCT) was used to conduct in situ imaging of AT microstructure across the surface of the human brain. OCT images were segmented to quantify the relative amounts of trabecular structures through a volume fraction (VF) measurement. The average VF for each brain ranged from 22.0% to 29.2%. Across all brains, there was a positive spatial correlation, with VF significantly greater by 12% near the superior aspect of the brain (p < .005), and significantly greater by 5%-10% in the frontal lobes (p < .005). These findings suggest that the distribution of AT between the brain and skull is heterogeneous, region-dependent, and likely contributes to brain deformation patterns. This study is the first to image and quantify human AT across the cerebrum and identify region-dependencies. Incorporation of this spatial heterogeneity may improve the accuracy of computational models of human TBI and enhance understanding of brain dynamics.
Topics: Adult; Aged; Aged, 80 and over; Arachnoid; Brain; Female; Humans; Male; Middle Aged; Pia Mater; Skull; Tomography, Optical Coherence
PubMed: 32202332
DOI: 10.1111/joa.13186