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Clinical Neurology and Neurosurgery Jun 2020The objective of this study was to summarize the available literature describing the presentation, diagnostic evaluation, and management for adults with Type 1 and Type... (Review)
Review
The objective of this study was to summarize the available literature describing the presentation, diagnostic evaluation, and management for adults with Type 1 and Type 2 split spinal cord malformations. A review of the literature was performed using the CINAHL, PubMed, Embase, and Web of Science database, alongside all associated bibliographies, to include studies describing Type 1 and Type 2 split cord malformations diagnosed in patients above the age of 18. All relevant studies of split cord malformations were included, regardless of the year published and terminology used to describe the dysraphism. Clinical case series (≥ 2 patients), cohort studies, and review articles comprising adult patients with radiographically diagnosed diastematomyelia, diplomyelia, or dimyelia were included (Class of Evidence I-IV). A total of 17 unique articles, describing 146 unique adult spinal cord malformation subjects, were included. The most common associated condition was tethered cord syndrome (59.8 %). Operative management for symptomatic split cord malformation was performed in 72.3 % of cases. For those with preoperative neurologic deficits, operative management resulted in symptomatic improvement in 96.6 %, compared to 0 % conservative management (p < 0.05). For those with pain alone, operative management resulted in improvement of 91.1 %, compared to 12.5 % conservative management (p < 0.05). To date, this is the only literature review to include all split cord malformations (SCM Types I and II) presenting in adulthood, with clinical characteristics, associated conditions, and long-term treatment outcomes.
Topics: Humans; Magnetic Resonance Imaging; Neurosurgical Procedures; Spinal Cord; Spinal Cord Diseases; Treatment Outcome
PubMed: 32146230
DOI: 10.1016/j.clineuro.2020.105733 -
Clinical Neurophysiology : Official... Feb 2008
Topics: Humans; Monitoring, Intraoperative; Spinal Cord
PubMed: 18032099
DOI: 10.1016/j.clinph.2007.10.002 -
Experimental Neurology Jun 2008Substantial progress has been made towards understanding the molecular basis for limited endogenous central nervous system (CNS) axonal growth after injuries such as... (Review)
Review
Substantial progress has been made towards understanding the molecular basis for limited endogenous central nervous system (CNS) axonal growth after injuries such as spinal cord trauma. Realization of the potential benefit of therapeutic interventions requires methods to assess axonal growth and functional reorganization over time after neurological damage. Here, we discuss the technical challenges of analyzing and interpreting the effects of various interventions on CNS repair, specifically in the context of spinal cord injury. Evolving technologies such as functional magnetic resonance imaging and other non-invasive imaging techniques will be reviewed. These technologies should revolutionize our ability to track changes in both CNS structure and function.
Topics: Animals; Disease Models, Animal; Humans; Magnetic Resonance Imaging; Spinal Cord; Spinal Cord Injuries
PubMed: 18396280
DOI: 10.1016/j.expneurol.2008.02.017 -
Progress in Brain Research 2000
Review
Topics: Animals; Lampreys; Models, Animal; Neuronal Plasticity; Neurons; Spinal Cord
PubMed: 11098674
DOI: 10.1016/S0079-6123(00)25027-9 -
Journal of Neurophysiology Dec 2020The gray matter of the spinal cord is the seat of somata of various types of neurons devoted to the sensory and motor activities of the limbs and trunk as well as a part...
The gray matter of the spinal cord is the seat of somata of various types of neurons devoted to the sensory and motor activities of the limbs and trunk as well as a part of the autonomic nervous system. The volume of the spinal gray matter is an indicator of the local neuronal processing, and this can decrease due to atrophy associated with degenerative diseases and injury. Nevertheless, the absolute volume of the human spinal cord has rarely been reported, if ever. Here, we use high-resolution magnetic resonance imaging, with a cross-sectional resolution of 50 × 50 μm and a voxel size of 0.0005 mm to estimate the total gray and white matter volume of a post mortem human female spinal cord. Segregation of gray and white matter was accomplished using deep learning image segmentation. Furthermore, we include data from a male spinal cord of a previously published study. The gray and white matter volumes were found to be 2.87 and 11.33 mL, respectively, for the female and 3.55 and 19.33 mL, respectively, for the male. The gray and white matter profiles along the vertebral axis were found to be strikingly similar, and the volumes of the cervical, thoracic, and lumbosacral sections were almost equal. Here, we combine high-field MRI (9.4 T) and deep learning for a post mortem reconstruction of the gray and white matter in human spinal cords. We report a minuscule total gray matter volume of 2.87 mL for a female and 3.55 mL for a male. For comparison, these volumes correspond approximately to the distal digit of the little finger.
Topics: Aged, 80 and over; Deep Learning; Female; Gray Matter; Humans; Magnetic Resonance Imaging; Male; Neuroimaging; Spinal Cord; White Matter
PubMed: 33085549
DOI: 10.1152/jn.00413.2020 -
PloS One 2014Spinal cord injury (SCI) can induce prolonged spinal cord compression that may result in a reduction of local tissue perfusion, progressive ischemia, and potentially...
Spinal cord injury (SCI) can induce prolonged spinal cord compression that may result in a reduction of local tissue perfusion, progressive ischemia, and potentially irreversible tissue necrosis. Due to the combination of risk factors and the varied presentation of symptoms, the appropriate method and time course for clinical intervention following SCI are not always evident. In this study, a three-dimensional finite element fluid-structure interaction model of the cervical spinal cord was developed to examine how traditionally sub-clinical compressive mechanical loads impact spinal arterial blood flow. The spinal cord and surrounding dura mater were modeled as linear elastic, isotropic, and incompressible solids, while blood was modeled as a single-phased, incompressible Newtonian fluid. Simulation results indicate that anterior, posterior, and anteroposterior compressions of the cervical spinal cord have significantly different ischemic potentials, with prediction that the posterior component of loading elevates patient risk due to the concomitant reduction of blood flow in the arterial branches. Conversely, anterior loading compromises flow through the anterior spinal artery but minimally impacts branch flow rates. The findings of this study provide novel insight into how sub-clinical spinal cord compression could give rise to certain disease states, and suggest a need to monitor spinal artery perfusion following even mild compressive loading.
Topics: Finite Element Analysis; Models, Theoretical; Regional Blood Flow; Software; Spinal Cord; Spinal Cord Compression
PubMed: 25268384
DOI: 10.1371/journal.pone.0108820 -
Current Opinion in Neurobiology Feb 1993The study of the formation of synaptic circuits within the spinal cord has been hampered by the absence of accessible experimental preparations and suitable techniques.... (Review)
Review
The study of the formation of synaptic circuits within the spinal cord has been hampered by the absence of accessible experimental preparations and suitable techniques. Recently, two new preparations have been described for following spinal development in vitro: slices of embryonic rat spinal cord co-cultured with sensory ganglia and myotubes, and cultures of the entire central nervous system of neonatal opossums. Optical imaging techniques have revealed spontaneous synchronous increases of Ca2+ levels in groups of spinal neurons. The widespread electrical coupling among developing spinal neurons, which may contribute to these synchronous bursts, becomes highly restricted as development proceeds. Both phenomena may play central roles in the formation of specific patterns of synaptic connections.
Topics: Animals; Humans; Neural Pathways; Spinal Cord; Synapses
PubMed: 8453295
DOI: 10.1016/0959-4388(93)90039-2 -
NeuroImage Aug 2020Dermatomal maps are a mainstay of clinical practice and provide information on the spatial distribution of the cutaneous innervation of spinal nerves. Dermatomal...
Assessing the spatial distribution of cervical spinal cord activity during tactile stimulation of the upper extremity in humans with functional magnetic resonance imaging.
Dermatomal maps are a mainstay of clinical practice and provide information on the spatial distribution of the cutaneous innervation of spinal nerves. Dermatomal deficits can help isolate the level of spinal nerve root involvement in spinal conditions and guide clinicians in diagnosis and treatment. Dermatomal maps, however, have limitations, and the spatial distribution of spinal cord sensory activity in humans remains to be quantitatively assessed. Here we used spinal cord functional MRI to map and quantitatively compare the spatial distribution of sensory spinal cord activity during tactile stimulation of the left and right lateral shoulders (i.e. C5 dermatome) and dorsal third digits of the hands (i.e., C7 dermatome) in healthy humans (n = 24, age = 36.8 ± 11.8 years). Based on the central sites for processing of innocuous tactile sensory information, we hypothesized that the activity would be localized more to the ipsilateral dorsal spinal cord with the lateral shoulder stimulation activity being localized more superiorly than the dorsal third digit. The findings demonstrate lateralization of the activity with the left- and right-sided stimuli having more activation in the ipsilateral hemicord. Contradictory to our hypotheses, the activity for both stimulation sites was spread across the dorsal and ventral hemicords and did not demonstrate a clear superior-inferior localization. Instead, the activity for both stimuli had a broader than expected distribution, extending across the C5, C6, and C7 spinal cord segments. We highlight the complexity of the human spinal cord neuroanatomy and several sources of variability that may explain the observed patterns of activity. While the findings were not completely consistent with our a priori hypotheses, this study provides a foundation for continued work and is an important step towards developing normative quantitative spinal cord measures of sensory function, which may become useful objective MRI-based biomarkers of neurological injury and improve the management of spinal disorders.
Topics: Adult; Cervical Cord; Female; Fingers; Functional Laterality; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Male; Middle Aged; Physical Stimulation; Spinal Cord; Touch; Upper Extremity; Young Adult
PubMed: 32387628
DOI: 10.1016/j.neuroimage.2020.116905 -
Fluids and Barriers of the CNS Apr 2018Cerebrospinal fluid (CSF) is thought to flow into the brain via perivascular spaces around arteries, where it mixes with interstitial fluid. The precise details...
BACKGROUND
Cerebrospinal fluid (CSF) is thought to flow into the brain via perivascular spaces around arteries, where it mixes with interstitial fluid. The precise details concerning fluid outflow remain controversial. Although fluid dynamics have been studied in the brain, little is known about spinal cord fluid inflow and outflow. Understanding the normal fluid physiology of the spinal cord may give insight into the pathogenesis of spinal cord oedema and CSF disorders such as syringomyelia. We therefore aimed to determine the fluid outflow pathways in the rat spinal cord.
METHODS
A fluorescent tracer, Alexa-Fluor-647 Ovalbumin, was injected into the extracellular space of either the cervicothoracic lateral white matter or the grey matter in twenty-two Sprague-Dawley rats over 250 s. The rats were sacrificed at 20 or 60 min post injection. Spinal cord segments were sectioned and labelled with vascular antibodies for immunohistochemistry.
RESULTS
Fluorescent tracer was distributed over two to three spinal levels adjacent to the injection site. In grey matter injections, tracer spread radially into the white matter. In white matter injections, tracer was confined to and redistributed along the longitudinal axonal fibres. Tracer was conducted towards the pial and ependymal surfaces along vascular structures. There was accumulation of tracer around the adventitia of the intramedullary arteries, veins and capillaries, as well as the extramedullary vessels. A distinct layer of tracer was deposited in the internal basement membrane of the tunica media of arteries. In half the grey matter injections, tracer was detected in the central canal.
CONCLUSIONS
These results suggest that in the spinal cord interstitial fluid movement is modulated by tissue diffusivity of grey and white matter. The central canal, and the compartments around or within blood vessels appear to be dominant pathways for fluid drainage in these experiments. There may be regional variations in fluid outflow capacity due to vascular and other anatomical differences between the grey and white matter.
Topics: Animals; Cerebrospinal Fluid; Gray Matter; Male; Rats, Sprague-Dawley; Spinal Cord; White Matter
PubMed: 29704892
DOI: 10.1186/s12987-018-0098-1 -
Scientific Reports May 2017Diagnosis of nervous system disease is greatly aided by functional assessments and imaging techniques that localize neural activity abnormalities. Electrophysiological...
Diagnosis of nervous system disease is greatly aided by functional assessments and imaging techniques that localize neural activity abnormalities. Electrophysiological methods are helpful but often insufficient to locate neural lesions precisely. One proposed noninvasive alternative is magnetoneurography (MNG); we have developed MNG of the spinal cord (magnetospinography, MSG). Using a 120-channel superconducting quantum interference device biomagnetometer system in a magnetically shielded room, cervical spinal cord evoked magnetic fields (SCEFs) were recorded after stimulation of the lower thoracic cord in healthy subjects and a patient with cervical spondylotic myelopathy and after median nerve stimulation in healthy subjects. Electrophysiological activities in the spinal cord were reconstructed from SCEFs and visualized by a spatial filter, a recursive null-steering beamformer. Here, we show for the first time that MSG with high spatial and temporal resolution can be used to map electrophysiological activities in the cervical spinal cord and spinal nerve.
Topics: Adult; Aged; Cervical Cord; Electrophysiological Phenomena; Humans; Magnetic Resonance Imaging; Male; Neuroimaging; Spinal Cord; Thoracic Vertebrae
PubMed: 28526877
DOI: 10.1038/s41598-017-02406-8