Confusing date July 2008 Infobox Anatomy Name Endoneurium Latin GraySubject 183 GrayPage 728 Image Gray636.png Caption Transverse section of human tibial nerve . Image2 Illu nerve structure.jpg Caption2 Nerve structure System MeshName Endoneurium MeshNumber A08.800.800 DorlandsPre e 09 DorlandsSuf 12332510 Code Terminologia Anatomica TA A14.2.00.014 The endoneurium , also referred to as an endoneurial channel, sheath or tube, is a layer of delicate connective tissue made up of endoneurial cells that encloses the myelin sheath of a spinal cord nerve fiber . ref name Marieb cite book author Elaine N. Marieb and Katja Hoehn title Human Anatomy & Physiology 7th Ed. publisher Pearson pages 498 9 year 2007 isbn 0 805 35909 5 ref These are bundled up into groups called nerve fascicle s, which have a protective sheath called a perineurium . Several fascicles may be in turn bundled together with a blood supply and fatty tissue within yet another sheath, the epineurium. The endoneurium contains a low protein liquid known as endoneurial fluid that is the peripheral nervous system equivalent to cerebro spinal fluid in the central nervous system . Peripheral nerve injuries can be identified by checking for increased amounts of endoneurial fluid using magnetic resonance neurography . It is continuous with septa which pass inward from the innermost layer of the perineurium, and shows a ground substance in which are imbedded fine bundles of fibrous connective tissue , primarily collagen , running for the most part longitudinally. It serves to support capillary blood vessel s, arranged so as to form a network with elongated meshes. It is found in other places too, such as surrounding the Schwann cell s on the peripheral side of the transitional zone on the auditory nerve . ref cite journal author Fraher JP title The transitional zone and CNS regeneration journal J. Anat. volume 196 issue ... Endoneurium BUHistology 21301loa Ultrastructure of the Cell myelinated axon and Schwann ... more details
A nerve contains two types of tissue 1 nerve fibers, and 2 connective tissue. Dendrites and axons with schwann cells and myelin sheath are surrounded by connective tissue . A nerve fiber in the peripheral nervous system consists of an axon or long dendrite, myelin sheath if existence and their schwann cells. Peripheral sensory fibers contain long dendrites, but peripheral motor fibers have long axons. Long dendrites of sensory fibers have structural properties as motor axons. Layers of connective tissue in the nerve The three layers of connective tissue surround each nerve are Epineurium Perineurium Endoneurium Epineurium The epineurium surrounds the nerve trunk i.e. Superficial epineurium . This is considered the outermost layer. The epineurium separates the nerve fascicles, but lies outside the perineurium i.e. Interfascicular epineurium . Perineurium Each nerve fascicle is surrounded by the perineurium that includes a group of nerve fibers. The perineurium has very important role in the protection and support from nerve fibers. This section of connective tissue is an important factor in preventing the passing of large molecules from the epineurium into a fascicle. Endoneurium Each nerve fiber is surrounded by the endoneurium . This section is a thin layer of connective tissue. The endoneurium is the tube that places the components of a nerve fiber such as axon, the myelin sheath and Schwann cells into itself. Thus, the endoneurium separates nerve fibers of a fascicle. See also Nerve Epineurium Perineurium Endoneurium Connective tissue in skeletal muscle Nerve fascicle Nerve tissue Nerve fiber Connective tissue References fa fa Williams & Warwick. Gray s Anatomy .THIRTY SEVENTH EDITION.ISBN 0 443 04177 6 Nervous tissue Category Histology Category Soft tissue Category Peripheral nervous system Category Neuroanatomy fa ... more details
Infobox Anatomy Name PAGENAME Latin GraySubject 183 GrayPage 728 Image Gray636.png Caption Transverse section of human tibial nerve . Perineurium labeled at upper right. Image2 Illu nerve structure.jpg Caption2 Nerve structure System MeshName Perineurium MeshNumber A08.800.800 DorlandsPre p 13 DorlandsSuf 12627709 Code Terminologia Anatomica TA A14.2.00.015 In the peripheral nervous system , nerve fibers are each wrapped in a protective sheath known as the endoneurium . These are bundled together into groups known as Nerve fascicle fascicles , each surrounded by a protective sheath known as the perineurium . ref cite book last McCracken first Thomas title New Atlas of Human Anatomy year 1999 publisher Metro Books location China isbn 1 5866 3097 0 pages 96 97 ref Several fascicles may be in turn bundled together with a blood supply and fatty tissue within yet another sheath, the epineurium . This grouping structure is analogous to the muscular organization system of epimysium , perimysium and endomysium . The perineurium is composed of connective tissue , which has a distinctly lamellar arrangement consisting of roughly 7 8 concentric layers. The perineurium is cellular, and is composed of perineurial cells, which are epithelioid myofibroblasts . Perineurial cells are sometimes referred to as myoepithelioid due to their epithelioid and myofibroblastoid properties including tight junctions , gap junctions , external laminae and contractility. The perineurium is a smooth, transparent tubular membrane which may be easily separated from the fibers it encloses. In contrast, the epineurium is a tough and mechanically resistant tissue which is not easily penetrated by a needle. See also Nerve fascicle Endoneurium Epineurium Connective tissue in the peripheral nervous system References reflist External links eMedicineDictionary Perineurium OklahomaHistology 1 03 Peripheral nerve UCDavisOrganology nervous pns nerve1 nerve2 PNS, nerve LM, Low BUHistology 21401loa http www.med. ... more details
Infobox Anatomy Name Nerve fascicle Latin GraySubject 183 GrayPage 728 Image Gray636.png Caption Transverse section of human tibial nerve . Image2 Illu nerve structure.jpg Caption2 Nerve structure System MeshName MeshNumber DorlandsPre DorlandsSuf A small bundle of nerve fibers, enclosed by the perineurium , is called a fasciculus if the nerve is of small size, it may consist only of a single fasciculus but if large, the fasciculi are collected together into larger bundles or funiculus neurology funiculi , which are bound together in a common membranous investment. See also Perineurium Epineurium Endoneurium Nerve fiber Connective tissue in the peripheral nervous system External links UCDavisOrganology nervous pns nerve1 nerve3 PNS, nerve LM, Low http neuromedia.neurobio.ucla.edu campbell nervous wp images 182 TS LP.gif Histology at neurobio.ucla.edu Nervous tissue Gray s Category Nervous system neuroscience stub fa ... more details
an axon Or long dendrite , myelin sheath if existence , their schwann cells, and the endoneurium .... In third degree injury, there is a lesion of the endoneurium, but the epineurium and perineurium remain ... more details
and subdivide it into several bundles of fibers. Surrounding each such fiber is the endoneurium ... the axon synapses with its muscle fibers, or ends in sensory receptor s. The endoneurium consists ... requirements. Within the endoneurium, the individual nerve fibers are surrounded by a low protein liquid called endoneurial fluid. The endoneurium has properties analogous to the blood brain barrier ... more details
Infobox Anatomy Name Epineurium Latin GraySubject 183 GrayPage 728 Image Gray636.png Caption Transverse section of human tibial nerve . Epineurium labeled at upper right. Image2 Illu nerve structure.jpg Caption2 Nerve structure System MeshName Epineurium MeshNumber A08.800.800 DorlandsPre e 12 DorlandsSuf 12338150 The epineurium is the outermost layer of connective tissue surrounding a peripheral nerve . ref cite book last McCracken first Thomas title New Atlas of Human Anatomy year 1999 publisher Metro Books location China isbn 1 5866 3097 0 pages 96 97 ref It is made of dense irregular connective tissue and usually contains multiple nerve fascicle nerve fascicles as well as blood vessels which supply the nerve. Smaller branches of these blood vessels penetrate into the perineurium . The epineurium is formed when the spinal nerve leaves the vertebral canal via the intervertebral foramen and 2 layers of the spinal meninges invaginate the nerve arachnoid and dura forming a dural sleeve which is the epineurium. See also Perineurium Endoneurium Nerve fascicle Connective tissue in the peripheral nervous system References reflist External links UCDavisOrganology nervous pns nerve1 nerve1 PNS, nerve LM, Low UCDavisOrganology nervous pns nerve2 nerve1 PNS, nerve LM, Medium http www.med.howard.edu anatomy gas wk2 images image2.gif Diagram at Howard Nervous tissue Category Soft tissue Category Nervous system neuroscience stub circulatory stub it Perinevrio zh The epineurium is made up of collagen fibers and forms a tough fibrous sheath. This sheath is continuous with the dura mater of the spinal column at the intervertebral foramen. ... more details
Axonotmesis is a disruption of nerve cell axon, with Wallerian degeneration occurring below and slightly proximal to the site of injury. ref Otto D.Payton & Richard P.Di Fabio et al.Manual of physical therapy. Churchill Livingstone Inc. ISBN 0 443 08499 8 ref If axons , and their myelin sheath are damaged, but schwann cells , the endoneurium , perineurium and epineurium remain intact is called axonotmesis. Axonotmesis is usually the result of a more severe crush or contusion than neuropraxia . ref http www.medstudents.com.br neuroc neuroc4.htm ref . In axonotmesis, the proximal section is repaired by creating a sprout with its growth cone , but in the distal section occurs axonal degeneration. The rate of outgrowth of regenerating nerve fibers is about 1 mm to 2 mm per day, so that the recovery of conduction to a target structure depends on not only regrowth into the appropriate endoneurial tube endoneurium , but also on the distance involved. ref Carol Mattson Porth. Pathophysiology concepts of altered health states. Publisher Lippincott. Third Edition. ISBN 0 397 54723 4 ref Assessment A nerve contains sensory fibers, motor fibers, or both. Sensory fibers lesions cause the sensory problems below to the site of injury. Motor fibers injuries may involve lower motor neurons, sympathetic fibers, and or both. Assessment items include Sensory fibers that send sensory information to the central nervous system . Motor fibers that create the contraction of skeletal muscle . Sympathetic fibers that innervate the skin, and blood vessels of the upper and lower limbs. In assessment, sensory motor defects may be mild, moderate, or severe. Damage to motor fibers results in paralysis of the muscles. Nervous plexus injuries create the more signs and symptoms from sensory motor problems such as brachial plexus injuries . In these cases, the prognosis depends on the amount of damage and the degree of functional recovery. EMG and NCV findings Changes in EMG Electromyography EMG is a ... more details
Inline citations date November 2011 about the anatomical structure the comic book series Optic Nerve comic the album about David Wojnarowicz Optic Nerve CD ROM Infobox nerve Name Optic Nerve Latin nervus opticus Image2 Brain human normal inferior view with labels en.svg Caption2 Inferior view of the human brain, with the cranial nerves labelled. GraySubject 197 GrayPage 882 Image Gray773.png Caption The left optic nerve and the optic tract s. Innervates BranchFrom BranchTo MeshName Optic Nerve MeshNumber A08.800.800.120.680 Cranial nerves short The optic nerve , also known as cranial nerve 2, transmits visual information from the retina to the brain . Derived from the embryo nic retinal ganglion cell , a diverticulum located in the diencephalon , the optic nerve does not regenerate after transection. Anatomy The optic nerve is the second of twelve paired cranial nerve s but is considered to be part of the central nervous system , as it is derived from an outpouching of the diencephalon during embryonic development. As a consequence, the fibres are covered with myelin produced by oligodendrocyte s, rather than Schwann cell s, which are found in the peripheral nervous system , and are encased within the meninges . The name optic nerve is, in the technical sense, a misnomer, as the optic system lies within the central nervous system and therefore should be named the optic Neural tract tract , as nerves exist only, by definition, within the peripheral nervous system . Therefore, peripheral neuropathies like Guillain Barr syndrome do not affect the optic nerve. The optic nerve is ensheathed in all three meninges meningeal layers dura mater dura , arachnoid mater arachnoid , and pia mater rather than the epineurium , perineurium , and endoneurium found in peripheral nerves. Fibre tracks of the mammalian central nervous system as opposed to the peripheral nervous system are incapable of regeneration, and, hence, optic nerve damage produces irreversible blindness. The fibr ... more details
Infobox Anatomy Name Deep fascia Latin fascia profunda GraySubject 104 GrayPage 378 Image Caption Image2 Caption2 Precursor System Artery Vein Nerve Lymph MeshName MeshNumber Deep fascia or investing fascia is a layer of fascia which can surround individual muscles, and divide groups of muscles into compartments. This is the dense regular connective tissue dense fibrous connective tissue that interpenetrates and surrounds the muscles, bones, nerves and blood vessels of the body. It provides connection and communication in the form of aponeuroses , ligaments , tendons , retinaculum retinacula , joint capsule s, and septum septa . The deep fasciae envelop all bone periosteum and endosteum cartilage perichondrium , and blood vessels tunica externa and become specialized in muscles epimysium , perimysium , and endomysium and nerves epineurium , perineurium , and endoneurium . The high density of collagen fibers is what gives the deep fascia its strength and integrity. The amount of elastin fiber determines how much extensibility and resilience it will have. ref cite video people Hedley, Gil date 2005 title The Integral Anatomy Series Vol. 2 Deep Fascia and Muscle url http integralanatomy.com medium DVD publisher Integral Anatomy Productions accessdate 2006 07 17 ref Examples Examples include Fascia lata Fascia cruris Brachial fascia Buck s fascia Fascial dynamics Deep fascia is less extensible than superficial fascia. It is essentially avascular , ref cite book last Rolf first Ida P. title Rolfing publisher Healing Arts Press year 1989 location Rochester, VT pages 38 isbn 0 89281 335 0 ref but is richly innervated with sensory receptor s that report the presence of pain nociceptors change in movement proprioceptors change in pressure and vibration mechanoreceptors change in the chemical milieu chemoreceptors and fluctuation in temperature thermoreceptors ., ref cite book last Chaitow first Leon title Soft Tissue Manipulation publisher Healing Arts Press year 1988 locati ... more details
Lead too short date September 2009 DISPLAYTITLE List of subjects in Gray s Anatomy IX. Neurology The subjects listed below are covered by the 9th chapter of the 1858 anatomy textbook, Gray s Anatomy . Structure of the nervous system GraySubject 183 GrayPage 721 nerve fibers gray substance and white substance GrayPage 722 Neuroglia Nerve cells Unipolar cells Bipolar cells Multipolar cells Pyramidal cell GrayPage 723 Nerve cells axis cylinder process or axon protoplasmic processes or dendrons cyton Nissl s granules GrayPage 724 Nerve cells cone of origin Nerve fibers medullated fibers or white fibers GrayPage 725 medullated fibers or white fibers white substance of Schwann or medullary sheath neurolemma , primitive sheath , or nucleated sheath of Schwann axis cylinder primitive fibrillae of Schultze neurokeratin GrayPage 726 medullated fibers or white fibers medullary sheath , or white matter of Schwann GrayPage 727 medullated fibers or white fibers nodes of Ranvier internodal segment Ranvier s crosses Frommann s lines medullary segments , or segments of Lantermann neurolemma or primitive sheath Wallerian degeneration GrayPage 728 Non medullated Fibers Gray or gelatinous nerve fibers fibers of Remak Structure of the Peripheral nerves and Ganglia cerebrospinal nerves Nerve fibers funiculus Nerve fascicle fasciculi epineurium perineurium endoneurium vasomotor fibers spheroidal tactile corpuscles or end bulbs of Krause nervi nervorum plexus GrayPage 729 Structure of the Peripheral nerves and Ganglia sympathetic nerves sensory nerves , or centripetal nerves or afferent nerves centrifugal nerves or efferent nerves Origins and Terminations of Nerves GrayPage 730 origins or central terminations and peripheral terminations Origins of nerves superficial origin or apparent origin deep origin or real origin Peripheral terminations of nerves Motor nerves motor end plate Ganglia GrayPage 732 Neuron theory neuron synapse or synaptic membrane Nerve fascicle Fasciculi , tracts or fib ... more details
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