DOCSLIB.ORG

Review of Spinal Cord Basics of Neuroanatomy Brain Meninges

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Review of Spinal Cord Basics of Neuroanatomy Brain Meninges Review of Spinal Cord with Basics of Neuroanatomy Brain Meninges Prof. D.H. Pauža Parts of Nervous System Review of Spinal Cord with Basics of Neuroanatomy Brain Meninges Prof. D.H. Pauža Neurons and Neuroglia Neuron Human brain contains per 1011-12 (trillions) neurons Body (soma) Perikaryon Nissl substance or Tigroid Dendrites Axon Myelin Terminals Synapses Neuronal types Unipolar, pseudounipolar, bipolar, multipolar Afferent (sensory, centripetal) Efferent (motor, centrifugal, effector) Associate (interneurons) Synapse Presynaptic membrane Postsynaptic membrane, receptors Synaptic cleft Synaptic vesicles, neuromediator Mitochondria In human brain – neurons 1011 (100 trillions) Synapses – 1015 (quadrillions) Neuromediators •Acetylcholine •Noradrenaline •Serotonin •GABA •Endorphin •Encephalin •P substance •Neuronal nitric oxide Adrenergic nerve ending. There are many 50-nm-diameter vesicles (arrow) with dark, electron-dense cores containing norepinephrine. x40,000. Cell Types of Neuroglia Astrocytes - Oligodendrocytes – Ependimocytes - Microglia Astrocytes – a part of hemoencephalic barrier Oligodendrocytes Ependimocytes and microglial cells Microglia represent the endogenous brain defense and immune system, which is responsible for CNS protection against various types of pathogenic factors. After invading the CNS, microglial precursors disseminate relatively homogeneously throughout the neural tissue and acquire a specific phenotype, which clearly distinguish them from their precursors, the blood-derived monocytes. The ´resting´ microglia are the fastest moving cells in the brain Neuroglia in peripheral nervous system CNS PNS Neuronal lemmocytes (Schwann cells) Nerve fiber: myelinated and unmyelinated Impulse propagation speed: 0,5-120 m/s A, B, C types of nerve fibers Parts of Nervous System General definitions in neuroanatomy Meninges on spinal cord Dura mater, arachnoid and pia mater Epidural and subdural spaces Meninges on spinal cord Dura mater, arachnoid and pia mater Epidural and subdural spaces Meninges on brain: Dura mater, arachnoid and pia mater Meninges on brain: Dura mater, arachnoid and pia mater Meninges on Brain: Dura mater, arachnoid and pia mater Falx cerebri and Tentorium cerebeli Venal sinuses Meninges on Brain: Dura mater, arachnoid and pia mater Arachnoid villi, granulationes arachnoideae Meninges: Dura mater, arachnoid and pia mater Meninges: Dura mater, arachnoid and pia mater Subarachnoidal space Liquor or cerebrospinal fluid (CSF) Interpedicular cisterna Cisterna magna or cerebellomedulary cisterna Central canal and Brain ventricles Lateral, Third and Fourth Interventricular foramen Cerebral aqueduct Lateral and median apertures 4th ventricle Choroid plexus and Tela charoidea Cerebrospinal fluid Choroid plexus and Tela charoidea Cerebrospinal fluid Neuronal organization CNS: Grey matter: nuclei and cortex, functional nuclei White matter: pathways, fascicles Neuronal organization PNS: Ganglia and nerves Internal structure White matter: pathway (tractus), loop (lemniscus, ansa), decussatio, chiasma, stria. Anatomy of Spinal Cord Anatomy of Spinal Cord Conus medularis up to L2 Filum terminale Spinal cord Conus medularis, L2 Filum terminale SPINAL CORD External anatomy Cervical and lumbar enlargements; Anterior median fissure, Posterior median groove or sulcus, Posterior and anterior lateral sulci. SPINAL CORD External anatomy Anterior (motor) and posterior (sensory) spinal nerve roots, Spinal ganglion or dorsal root ganglion, Spinal nerve and its anterior and posterior branches . SPINAL CORD External anatomy Cauda equina Segments of spinal cord C1-8 Th1-12 L1-5 S1-5 Co1 INTERNAL ANATOMY OF SPINAL CORD Central canal; Grey matter: anterior3, posterior4 and lateral5 horns and columns (in lat., cornua anteriora, posteriora et laterale; columna anteriora, posteriora et intermedia), Central intermedial substance (in lat., substantia intermedia seu gelatinosa centralis) INTERNAL ANATOMY OF SPINAL CORD Grey matter: anterior, posterior and lateral horns and columns (cornua anteriora, posteriora et laterale; columna anteriora, posteriora et intermedia) Pars cervicalis Pars thoracica Pars lumbalis Principal Neuronal Organization in Spinal Cord INTERNAL ANATOMY OF SPINAL CORD Nucleus marginalis, Pain Grey matter: and temperature Sub.gelatinosa, signal transmission nucleus nuclei and/or laminae by Bror Rexed Pain and temperature signal transmission nucleus Nucleus proprius, I Sensation of skin Nucleus dorsalis (C8-L2) basilaris. Nucleus Proprioreception of the upper intermediolateralis and lower limbs Sympathetic nucleus IV (S2-4: Nucl.parasympathicus). (Parasympathetic) V VI VII X Nuclei VIII Substantia intermedia centralis. posteromedialis Nucleus of commissural neurons composing et centralis. commissura alba Associate neurons and descending pathways IX Nucleus intermediomedianalis interaction nucleus Sensation of internal organs Bror Rexed (June 19, 1914 - August 21, 2002) was a Swedish neuroscientist and professor Nuclei mediales et laterales. at Uppsala University. Internationally, he is best known today for his development of the system now known as Rexed laminae. Motor nucleus of muscles of trunk and Rexed B (1952). "The cytoarchitectonic organization of the spinal cord in the cat.". limbs J Comp Neurol 96 (3): 414-95. SPINAL CORD LAMINAE BY BROR REXED GREY MATTER NUCLEAR ORGANIZATION OF SPINAL NEURONS GREY MATTER NUCLEAR ORGANIZATION OF SPINAL NEURONS INTERNAL ANATOMY OF SPINAL CORD White matter: anterior, posterior and lateral funiculae (funiculus anterior, lateralis et posterior) White matter Anterior, posterior and lateral funiculae; Funiculus anterior, lateralis et posterior. Ascending and descending pathways; Funiculus proprius INTERNAL ANATOMY OF SPINAL CORD White matter: anterior, posterior and lateral funiculae (funiculus anterior, lateralis et posterior) Ascending and descending pathways; funiculus proprius Internal anatomy. White matter: ascending-afferent pathways Gracile fasciculus – tactile and proprioceptive sensations Cuneate fasciculus - tactile and proprioceptive sensations Spinothalamic tracts – pain and temperature sensation Spinocerebellar tracts – proprioceptive sensation Internal anatomy. White matter: descending-efferent pathways Pyramidal and extra- pyramidal pathways Lateral and anterior pyramidal tracts- striated muscles Rubrospinal tract – cerebellum and extrapyramidal system Tectospinal tract – unconditioned reflexes of skeletal muscles related to vision and hearing Vestibulospinal tract – regulation of equilibrium (balance) .
Load more

Recommended publications
  • NS201C Anatomy 1: Sensory and Motor Systems
    NS201C Anatomy 1: Sensory and Motor Systems 25th January 2017 Peter Ohara Department of Anatomy [email protected] The Subdivisions and Components of the Central Nervous System Axes and Anatomical Planes of Sections of the Human and Rat Brain Development of the neural tube 1 Dorsal and ventral cell groups Dermatomes and myotomes Neural crest derivatives: 1 Neural crest derivatives: 2 Development of the neural tube 2 Timing of development of the neural tube and its derivatives Timing of development of the neural tube and its derivatives Gestational Crown-rump Structure(s) age (Weeks) length (mm) 3 3 cerebral vesicles 4 4 Optic cup, otic placode (future internal ear) 5 6 cerebral vesicles, cranial nerve nuclei 6 12 Cranial and cervical flexures, rhombic lips (future cerebellum) 7 17 Thalamus, hypothalamus, internal capsule, basal ganglia Hippocampus, fornix, olfactory bulb, longitudinal fissure that 8 30 separates the hemispheres 10 53 First callosal fibers cross the midline, early cerebellum 12 80 Major expansion of the cerebral cortex 16 134 Olfactory connections established 20 185 Gyral and sulcul patterns of the cerebral cortex established Clinical case A 68 year old woman with hypertension and diabetes develops abrupt onset numbness and tingling on the right half of the face and head and the entire right hemitrunk, right arm and right leg. She does not experience any weakness or incoordination. Physical Examination: Vitals: T 37.0° C; BP 168/87; P 86; RR 16 Cardiovascular, pulmonary, and abdominal exam are within normal limits. Neurological Examination: Mental Status: Alert and oriented x 3, 3/3 recall in 3 minutes, language fluent.
    [Show full text]
  • The Creation of Neuroscience
    The Creation of Neuroscience The Society for Neuroscience and the Quest for Disciplinary Unity 1969-1995 Introduction rom the molecular biology of a single neuron to the breathtakingly complex circuitry of the entire human nervous system, our understanding of the brain and how it works has undergone radical F changes over the past century. These advances have brought us tantalizingly closer to genu- inely mechanistic and scientifically rigorous explanations of how the brain’s roughly 100 billion neurons, interacting through trillions of synaptic connections, function both as single units and as larger ensem- bles. The professional field of neuroscience, in keeping pace with these important scientific develop- ments, has dramatically reshaped the organization of biological sciences across the globe over the last 50 years. Much like physics during its dominant era in the 1950s and 1960s, neuroscience has become the leading scientific discipline with regard to funding, numbers of scientists, and numbers of trainees. Furthermore, neuroscience as fact, explanation, and myth has just as dramatically redrawn our cultural landscape and redefined how Western popular culture understands who we are as individuals. In the 1950s, especially in the United States, Freud and his successors stood at the center of all cultural expla- nations for psychological suffering. In the new millennium, we perceive such suffering as erupting no longer from a repressed unconscious but, instead, from a pathophysiology rooted in and caused by brain abnormalities and dysfunctions. Indeed, the normal as well as the pathological have become thoroughly neurobiological in the last several decades. In the process, entirely new vistas have opened up in fields ranging from neuroeconomics and neurophilosophy to consumer products, as exemplified by an entire line of soft drinks advertised as offering “neuro” benefits.
    [Show full text]
  • The Baseline Structure of the Enteric Nervous System and Its Role in Parkinson’S Disease
    life Review The Baseline Structure of the Enteric Nervous System and Its Role in Parkinson’s Disease Gianfranco Natale 1,2,* , Larisa Ryskalin 1 , Gabriele Morucci 1 , Gloria Lazzeri 1, Alessandro Frati 3,4 and Francesco Fornai 1,4 1 Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, 56126 Pisa, Italy; [email protected] (L.R.); [email protected] (G.M.); [email protected] (G.L.); [email protected] (F.F.) 2 Museum of Human Anatomy “Filippo Civinini”, University of Pisa, 56126 Pisa, Italy 3 Neurosurgery Division, Human Neurosciences Department, Sapienza University of Rome, 00135 Rome, Italy; [email protected] 4 Istituto di Ricovero e Cura a Carattere Scientifico (I.R.C.C.S.) Neuromed, 86077 Pozzilli, Italy * Correspondence: [email protected] Abstract: The gastrointestinal (GI) tract is provided with a peculiar nervous network, known as the enteric nervous system (ENS), which is dedicated to the fine control of digestive functions. This forms a complex network, which includes several types of neurons, as well as glial cells. Despite extensive studies, a comprehensive classification of these neurons is still lacking. The complexity of ENS is magnified by a multiple control of the central nervous system, and bidirectional communication between various central nervous areas and the gut occurs. This lends substance to the complexity of the microbiota–gut–brain axis, which represents the network governing homeostasis through nervous, endocrine, immune, and metabolic pathways. The present manuscript is dedicated to Citation: Natale, G.; Ryskalin, L.; identifying various neuronal cytotypes belonging to ENS in baseline conditions.
    [Show full text]
  • A Revised Computational Neuroanatomy for Motor Control
    This is the author’s final version; this article has been accepted for publication in the Journal of Cognitive Neuroscience 1 A Revised Computational Neuroanatomy for Motor Control 2 Shlomi Haar1, Opher Donchin2,3 3 1. Department of BioEngineering, Imperial College London, UK 4 2. Department of Biomedical Engineering, Ben-Gurion University of the Negev, Israel 5 3. Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Israel 6 7 Corresponding author: Shlomi Haar ([email protected]) 8 Imperial College London, London, SW7 2AZ, UK 9 10 Acknowledgements: We would like to thank Ilan Dinstein, Liad Mudrik, Daniel Glaser, Alex Gail, and 11 Reza Shadmehr for helpful discussions about the manuscript. Shlomi Haar is supported by the Royal 12 Society – Kohn International Fellowship (NF170650). Work on this review was partially supported by 13 DFG grant TI-239/16-1. 14 15 Abstract 16 We discuss a new framework for understanding the structure of motor control. Our approach 17 integrates existing models of motor control with the reality of hierarchical cortical processing and the 18 parallel segregated loops that characterize cortical-subcortical connections. We also incorporate the recent 19 claim that cortex functions via predictive representation and optimal information utilization. Our 20 framework assumes each cortical area engaged in motor control generates a predictive model of a different 21 aspect of motor behavior. In maintaining these predictive models, each area interacts with a different part 22 of the cerebellum and basal ganglia. These subcortical areas are thus engaged in domain appropriate 23 system identification and optimization. This refocuses the question of division of function among different 24 cortical areas.
    [Show full text]
  • Distance Learning Program Anatomy of the Human Brain/Sheep Brain Dissection
    Distance Learning Program Anatomy of the Human Brain/Sheep Brain Dissection This guide is for middle and high school students participating in AIMS Anatomy of the Human Brain and Sheep Brain Dissections. Programs will be presented by an AIMS Anatomy Specialist. In this activity students will become more familiar with the anatomical structures of the human brain by observing, studying, and examining human specimens. The primary focus is on the anatomy, function, and pathology. Those students participating in Sheep Brain Dissections will have the opportunity to dissect and compare anatomical structures. At the end of this document, you will find anatomical diagrams, vocabulary review, and pre/post tests for your students. The following topics will be covered: 1. The neurons and supporting cells of the nervous system 2. Organization of the nervous system (the central and peripheral nervous systems) 4. Protective coverings of the brain 5. Brain Anatomy, including cerebral hemispheres, cerebellum and brain stem 6. Spinal Cord Anatomy 7. Cranial and spinal nerves Objectives: The student will be able to: 1. Define the selected terms associated with the human brain and spinal cord; 2. Identify the protective structures of the brain; 3. Identify the four lobes of the brain; 4. Explain the correlation between brain surface area, structure and brain function. 5. Discuss common neurological disorders and treatments. 6. Describe the effects of drug and alcohol on the brain. 7. Correctly label a diagram of the human brain National Science Education
    [Show full text]
  • The Nerve Lesion in the Carpal Tunnel Syndrome
    J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.39.7.615 on 1 July 1976. Downloaded from Journal of Neurology, Neurosurgery, and Psychiatry, 1976, 39, 615-626 The nerve lesion in the carpal tunnel syndrome SYDNEY SUNDERLAND From the Department of Experimental Neurology, University of Melbourne, Parkville, Victoria, Australia SYNOPSIS The relative roles of pressure deformation and ischaemia in the production of compres- sion nerve lesions remain a controversial issue. This paper concerns the genesis of the structural changes which follow compression of the median nerve in the carpal tunnel. The initial lesion is an intrafunicular anoxia caused by obstruction to the venous return from the funiculi as the result of increased pressure in the tunnel. This leads to intrafunicular oedema and an increase in intrafunicular pressure which imperil and finally destroy nerve fibres by impairing their blood supply and by compression. The final outcome is the fibrous tissue replacement of the contents of the funiculi. Protected by copyright. In 1862 Waller described the motor, vasomotor, (Gasser, 1935; Allen, 1938; Bentley and Schlapp, and sensory changes which followed the com- 1943; Richards, 1951; Moldaver, 1954; Gelfan pression of nerves in his own arm. His account and Tarlov, 1956). carried no reference to the mechanism In the 1940s Weiss and his associates (Weiss, responsible for blocking conduction in the nerve 1943, 1944; Weiss and Davis, 1943; Weiss and fibres, presumably because he regarded it as Hiscoe, 1948), who were primarily concerned obvious that pressure was the offending agent. with the technical problem of uniting severed Interest in the effects of nerve compression nerves, observed that a divided nerve enclosed was not renewed until the 1920s when cuff or in a tightly fitting arterial sleeve became swollen tourniquet compression was used to produce a proximal and distal to the constriction.
    [Show full text]
  • Basal Ganglia & Cerebellum
    1/2/2019 This power point is made available as an educational resource or study aid for your use only. This presentation may not be duplicated for others and should not be redistributed or posted anywhere on the internet or on any personal websites. Your use of this resource is with the acknowledgment and acceptance of those restrictions. Basal Ganglia & Cerebellum – a quick overview MHD-Neuroanatomy – Neuroscience Block Gregory Gruener, MD, MBA, MHPE Vice Dean for Education, SSOM Professor, Department of Neurology LUHS a member of Trinity Health Outcomes you want to accomplish Basal ganglia review Define and identify the major divisions of the basal ganglia List the major basal ganglia functional loops and roles List the components of the basal ganglia functional “circuitry” and associated neurotransmitters Describe the direct and indirect motor pathways and relevance/role of the substantia nigra compacta 1 1/2/2019 Basal Ganglia Terminology Striatum Caudate nucleus Nucleus accumbens Putamen Globus pallidus (pallidum) internal segment (GPi) external segment (GPe) Subthalamic nucleus Substantia nigra compact part (SNc) reticular part (SNr) Basal ganglia “circuitry” • BG have no major outputs to LMNs – Influence LMNs via the cerebral cortex • Input to striatum from cortex is excitatory – Glutamate is the neurotransmitter • Principal output from BG is via GPi + SNr – Output to thalamus, GABA is the neurotransmitter • Thalamocortical projections are excitatory – Concerned with motor “intention” • Balance of excitatory & inhibitory inputs to striatum, determine whether thalamus is suppressed BG circuits are parallel loops • Motor loop – Concerned with learned movements • Cognitive loop – Concerned with motor “intention” • Limbic loop – Emotional aspects of movements • Oculomotor loop – Concerned with voluntary saccades (fast eye-movements) 2 1/2/2019 Basal ganglia “circuitry” Cortex Striatum Thalamus GPi + SNr Nolte.
    [Show full text]
  • The Strain Rates in the Brain, Brainstem, Dura, and Skull Under Dynamic Loadings
    Mathematical and Computational Applications Article The Strain Rates in the Brain, Brainstem, Dura, and Skull under Dynamic Loadings Mohammad Hosseini-Farid 1,2,* , MaryamSadat Amiri-Tehrani-Zadeh 3, Mohammadreza Ramzanpour 1, Mariusz Ziejewski 1 and Ghodrat Karami 1 1 Department of Mechanical Engineering, North Dakota State University, Fargo, ND 58104, USA; [email protected] (M.R.); [email protected] (M.Z.); [email protected] (G.K.) 2 Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN 55905, USA 3 Department of Computer Science, North Dakota State University, Fargo, ND 58104, USA; [email protected] * Correspondence: [email protected]; Tel.: +1-7012315859 Received: 7 March 2020; Accepted: 5 April 2020; Published: 7 April 2020 Abstract: Knowing the precise material properties of intracranial head organs is crucial for studying the biomechanics of head injury. It has been shown that these biological tissues are significantly rate-dependent; hence, their material properties should be determined with respect to the range of deformation rate they experience. In this paper, a validated finite element human head model is used to investigate the biomechanics of the head in impact and blast, leading to traumatic brain injuries (TBI). We simulate the head under various directions and velocities of impacts, as well as helmeted and unhelmeted head under blast shock waves. It is demonstrated that the strain rates for the brain 1 are in the range of 36 to 241 s− , approximately 1.9 and 0.86 times the resulting head acceleration under impacts and blast scenarios, respectively. The skull was found to experience a rate in the range 1 of 14 to 182 s− , approximately 0.7 and 0.43 times the head acceleration corresponding to impact and blast cases.
    [Show full text]
  • Deconstructing Spinal Interneurons, One Cell Type at a Time Mariano Ignacio Gabitto
    Deconstructing spinal interneurons, one cell type at a time Mariano Ignacio Gabitto Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy under the Executive Committee of the Graduate School of Arts and Sciences COLUMBIA UNIVERSITY 2016 © 2016 Mariano Ignacio Gabitto All rights reserved ABSTRACT Deconstructing spinal interneurons, one cell type at a time Mariano Ignacio Gabitto Abstract Documenting the extent of cellular diversity is a critical step in defining the functional organization of the nervous system. In this context, we sought to develop statistical methods capable of revealing underlying cellular diversity given incomplete data sampling - a common problem in biological systems, where complete descriptions of cellular characteristics are rarely available. We devised a sparse Bayesian framework that infers cell type diversity from partial or incomplete transcription factor expression data. This framework appropriately handles estimation uncertainty, can incorporate multiple cellular characteristics, and can be used to optimize experimental design. We applied this framework to characterize a cardinal inhibitory population in the spinal cord. Animals generate movement by engaging spinal circuits that direct precise sequences of muscle contraction, but the identity and organizational logic of local interneurons that lie at the core of these circuits remain unresolved. By using our Sparse Bayesian approach, we showed that V1 interneurons, a major inhibitory population that controls motor output, fractionate into diverse subsets on the basis of the expression of nineteen transcription factors. Transcriptionally defined subsets exhibit highly structured spatial distributions with mediolateral and dorsoventral positional biases. These distinctions in settling position are largely predictive of patterns of input from sensory and motor neurons, arguing that settling position is a determinant of inhibitory microcircuit organization.
    [Show full text]
  • A Cellular Atlas of the Developing Meninges Reveals Meningeal Fibroblast Diversity and Function
    bioRxiv preprint doi: https://doi.org/10.1101/648642; this version posted May 24, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. 1 2 3 4 Title: A cellular atlas of the developing meninges reveals meningeal fibroblast diversity and function 5 6 Authors: John DeSisto1,2,3,, Rebecca O’Rourke2, Stephanie Bonney1,3, Hannah E. Jones1,3, Fabien 7 Guimiot4, Kenneth L. Jones2 and Julie A. Siegenthaler1,3,5 8 9 1Department of Pediatrics Section of Developmental Biology, 2Department of Pediatrics Section of 10 Section of Hematology, Oncology, Bone Marrow Transplant, 3Cell Biology, Stem Cells and Development 11 Graduate Program, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045 USA, 12 4INSERM UMR 1141, Hôpital Robert Debré, 75019 Paris, France. 13 14 5Corresponding Author: 15 Julie A. Siegenthaler, PhD 16 University of Colorado, School of Medicine 17 Department of Pediatrics 18 12800 East 19th Ave MS-8313 19 Aurora, CO 80045 USA 20 Telephone #: 303-724-3123 21 E-mail: [email protected] 22 23 Key words (3-6 words): brain development, meninges, pial basement membrane, retinoic acid, human 24 meninges bioRxiv preprint doi: https://doi.org/10.1101/648642; this version posted May 24, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. 25 Abstract 26 The meninges, a multilayered structure that encases the CNS, is composed mostly of fibroblasts, 27 along with vascular and immune cells.
    [Show full text]
  • Imaging of the Confused Patient: Toxic Metabolic Disorders Dara G
    Imaging of the Confused Patient: Toxic Metabolic Disorders Dara G. Jamieson, M.D. Weill Cornell Medicine, New York, NY The patient who presents with either acute or subacute confusion, in the absence of a clearly defined speech disorder and focality on neurological examination that would indicate an underlying mass lesion, needs to be evaluated for a multitude of neurological conditions. Many of the conditions that produce the recent onset of alteration in mental status, that ranges from mild confusion to florid delirium, may be due to infectious or inflammatory conditions that warrant acute intervention such as antimicrobial drugs, steroids or plasma exchange. However, some patients with recent onset of confusion have an underlying toxic-metabolic disorders indicating a specific diagnosis with need for appropriate treatment. The clinical presentations of some patients may indicate the diagnosis (e.g. hypoglycemia, chronic alcoholism) while the imaging patterns must be recognized to make the diagnosis in other patients. Toxic-metabolic disorders constitute a group of diseases and syndromes with diverse causes and clinical presentations. Many toxic-metabolic disorders have no specific neuroimaging correlates, either at early clinical stages or when florid symptoms develop. However, some toxic-metabolic disorders have characteristic abnormalities on neuroimaging, as certain areas of the central nervous system appear particularly vulnerable to specific toxins and metabolic perturbations. Areas of particular vulnerability in the brain include: 1) areas of high-oxygen demand (e.g. basal ganglia, cerebellum, hippocampus), 2) the cerebral white matter and 3) the mid-brain. Brain areas of high-oxygen demand are particularly vulnerable to toxins that interfere with cellular respiratory metabolism.
    [Show full text]
  • Meninges,Cerebrospinal Fluid, and the Spinal Cord
    The Nervous System SPINAL CORD Spinal Cord Continuation of CNS inferior to foramen magnum (medulla) Simpler Conducts impulses to and from brain Two way conduction pathway Reflex actions Spinal Cord Passes through vertebral canal Foramen magnum L2 Conus medullaris Filum terminale Cauda equina Cervical Cervical spinal nerves enlargement Dura and arachnoid Thoracic mater spinal nerves Lumbar enlargement Conus medullaris Lumbar Cauda spinal nerves equina Filum (a) The spinal cord and its nerve terminale Sacral roots, with the bony vertebral spinal nerves arches removed. The dura mater and arachnoid mater are cut open and reflected laterally. Figure 12.29a Spinal Cord Spinal nerves 31 pairs Cervical and lumbar enlargements The nerves serving the upper and lower limbs emerge here Cervical Cervical spinal nerves enlargement Dura and arachnoid Thoracic mater spinal nerves Lumbar enlargement Conus medullaris Lumbar Cauda spinal nerves equina Filum (a) The spinal cord and its nerve terminale Sacral roots, with the bony vertebral spinal nerves arches removed. The dura mater and arachnoid mater are cut open and reflected laterally. Figure 12.29a Spinal Cord Protection Bone, meninges, and CSF Spinal tap-inferior to second lumbar vertebra T12 Ligamentum flavum L5 Lumbar puncture needle entering subarachnoid space L4 Supra- spinous ligament L5 Filum terminale S1 Inter- Cauda equina vertebral Arachnoid Dura in subarachnoid disc matter mater space Figure 12.30 Spinal Cord Cross section Central gray matter Cortex of white matter Epidural
    [Show full text]