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| | Nerve injuries |
 | | If both the nerve and insulation have been cut and the nerve is not fixed, the growing nerve fibers may grow into a ball at the end of the cut, forming a nerve scar or neuroma. | | | When nerve fibers are cut, the end of the fiber farthest from the brain dies, while the insulation stays healthy. | | | After the nerve has recovered, the brain gets "lazy," and a procedure called sensory re-education may be needed to improve feeling to the hand or finger. |
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http://orthoinfo.aaos.org/brochure/thr_report.cfm?thread_id=49&...
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| | NeuroSoma® - A Limited Pressure Muscle Spindle Myotherapy - About the Stretch Reflex Mechanism |
| | In the basic circuit of the muscle spindle stretch reflex, a type Ia fiber (annulospiral nerve), originates in the muscle spindle and enters the dorsal root of the spinal cord. | | | Then, in contrast to most other nerve fibers entering the cord, one branch of it passes directly to the anterior horn of the cord gray matter and synapses directly with anterior motor neurons that send nerve fibers back to the same muscle from whence the muscle spindle fiber originated. | | | To emphasize the importance of the gamma efferent system, one needs to recognize that 31 percent of all the motor nerve fibers to the muscle are gamma efferent fibers rather than large, type A alpha motor fibers. |
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http://www.neurosoma.com/stretch.html
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| | Eye Tests > Optic nerve imaging -- EyeMDLink.com |
| | The GDx Nerve Fiber Analyzer is an instrument that uses laser to determine the thickness of the nerve fiber layer. | | | The nerve fiber layer itself is the tissue that the optic nerve is made up of and, therefore, detection of thinning of the nerve fiber layer may be correlated with risk of glaucoma or progression thereof. | | | Imaging of the optic nerve head for patients who have glaucoma, or are being observed for possible glaucoma, has traditionally been completed with optic nerve photography which remains the standard of analysis. |
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http://www.eyemdlink.com/Test.asp?TestID=24
(764 words)
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| | Complex Regional Pain Syndrome Type 1 |
| | Peripheral nerve blocks can provide a degree of sympathetic block as there are ‘sympathetic nerve fibers that travel for variable distances with the somatic nerves but in general the more distally the block is done then the lower is the likelihood of providing a significant pain relief’ (Hamill and Rowlingson, 1994,p: 547). | | | This may be outside the distribution of any single peripheral nerve (Purdy and Miller, 1992). | | | That is the ‘dominant small fiber input could result in unchecked transmission of pain through an open gate’ (Purdy and Miller, 1992,p: 1127). |
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http://podiatry.curtin.edu.au/encyclopedia/crps1
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| | S030439409800167.abstract.en |
| | These results suggest that the degree of sympathetic dependence of neuropathic pain is not a function of the extent of the sympathetic postganglionic nerve fiber sprouting in the DRG. | | | Incomplete peripheral nerve injury often leads to neuropathic pains, some of which are relieved by sympathectomy, and results in sympathetic postganglionic nerve fiber sprouting in the dorsal root ganglion (DRG). | | | This study was performed to see whether the sprouting in the DRG plays a key role in the sympathetic dependence of neuropathic pain. |
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http://www.elsevier.com/cdweb/journals/03043940/articles/245/1/S030439409800167.abstract.en
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| | Neurodiagnostic Skin Biopsies at Massachusetts General Hospital |
| | Epidermal nerve fiber density and sural nerve morphometry in peripheral neuropathies. | | | The types of nerve cells that are damaged in painful sensory neuropathies (small, unmyelinated and thinly myelinated axons) are not well studied by EMG and NCS, and these tests can give false "normal" results in patients with small-fiber neuropathies. | | | In addition, skin biopsy may even be more sensitive than sural nerve biopsy because it samples the nerves closer to their endings in the skin, where disease usually starts. |
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http://neuroskinbiopsy.mgh.harvard.edu
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| | Autonomic NS |
| | Preganglionic parasympathetic fibers leave the spinal nerve as the pelvic splanchnic nerves (to be learned later) but never reenter it to be distributed to the periphery. | | | in animals called preganglionic parasympathetic fibers comprise the "nervi erigens," energetic little nerves which control the reproductive organs, the sexual response, micturation, defecation, and the other pelvic viscera, assuming the function of the vagus below the transverse colon. | | | It is a solely efferent system, however, afferent visceral fibers, associated with the spinal nerve, travel with the efferent fibers and provide information to the CNS concerning the state of the viscera. |
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http://wings.buffalo.edu/smbs/ana/newpage41.htm
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| | IX. Neurology. 4e. Composition and Central Connections of the Spinal Nerves. Gray, Henry. 1918. Anatomy of the Human Body. |
| | The fibers arise from the nucleus of the abducens nerve and pass ventrally through the formatio reticularis of the pons to emerge in the transverse groove between the caudal edge of the pons and the pyramid. | | | A few of the fibers are said to pass by the inferior colliculus to terminate in the middle portion of the stratum griseum of the superior colliculus, and are probably concerned with reflex movements of the eyes depending on acoustic stimuli. | | | Fibers from the visual reflex center in the superior colliculus pass to the nucleus. |
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http://bartleby.com/107/191.html
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| | neurotox.html |
| | The nerve fiber connects either with another nerve fiber or with some other cell (such as a gland or cardiac, smooth, or skeletal muscle) capable of being stimulated by the nerve impulse (Fig. | | | A nerve impulse or stimulus is transmitted along a nerve fiber by electric impulses. | | | Applied to the skin, atropine sulfate and other atropine salts relieve pain by deactivating sensory nerve endings on the skin. |
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http://www.uky.edu/~holler/neurotox.html
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| | Nat' Academies Press, (NAS Colloquium) Auditory Neuroscience Development, Transduction, and Integration (2001) |
| | The polarity of auditory- nerve fiber excitation relative to BM vibrations at the base of the cochlea remains the most puzzling of our findings. | | | Here we review the cochlear mechanical bases of auditory- nerve excitation as revealed by comparisons of the magnitudes and phases of BM and auditory-nerve-fiber responses to tones recorded from a basal site of the chinchilla cochlea with CF ~ 9 kHz located about 3.5 mm from the oval window. | | | 6A displays the average phases of responses to 600-Hz tones of 27 chinchilla auditory- nerve fibers with CFs of 8-12 kHz, plotted as a function of stimulus intensity. |
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http://www.nap.edu/books/0309074223/html/55.html
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| | PAS-03-173: NEUROBIOLOGY OF PERSISTENT PAIN MEDIATED BY THE TRIGEMINAL NERVE |
| | Trigeminal neuralgia is characterized by intense pain arising from abnormal processing of signals from one or more of the peripheral branches of the trigeminal nerve. | | | The unique nature of nociceptive processing and varied etiology of pain conditions mediated by the trigeminal nerve contribute to the lack of understanding of the basic mechanisms of pain onset, and the development of chronic pain and abnormal pain responses (allodynia, hyperalgesia). | | | The pain of migraine is perceived in the somatic territory of the nerve. |
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http://grants.nih.gov/grants/guide/pa-files/PAS-03-173.html
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| | Early American Manual Therapy |
| | When a nerve impulse traverses a nerve trunk, there is produced in the fiber a change in its electrical conditiona wave of negativity which passes at the same rate and in the same direction as the wave of nerve impulse. | | | Nerve impulses must be essentially alike, yet the manner of their transmission, and even more the nature of their effects in consciousness, differ very widely. | | | The part of the nerve trunk which lies between the two electrodes is called the interpolar section; the area nearest the anode is in a condition of anelectrotonus, the part nearest the cathode is in a condition of catelectrotonus. |
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http://www.meridianinstitute.com/eamt/files/burns2/bur2ch02.html
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| | Neurology Journal Club Aricle #1 |
| | The only sensory nerve examined was the saphenous nerve from dog 6, and axonal degenerative changes were observed in approximately 7% of teased fibers. | | | The tibial nerve specimen obtained from this dog at the time of the second biopsy had a similar percentage of abnormal fibers as the sciatic nerve, but the frequency of axonal degeneration was higher in the distal specimen (Table 2). | | | Ultrastructurally, peripheral nerves from affected dogs were characterized by loss of myelinated fibers, marked increase in endoneurial collagen, axonal degeneration (Fig 4), multifocal myelinoaxonal necrosis (Fig 5), numerous Bungner bands (conglomerations of Schwann cells previously associated with myelinated axons)29 (Fig 6), multifocal macrophage infiltration, occasional regenerating clusters, and presence of dark endoneurial fibroblasts. |
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http://neuro.vetmed.ufl.edu/neuro/journal_club/articles/malamute_art.htm
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| | Neuropathic Disorders |
| | Nerve bundles closely associated with the xanthomata show compression of fascicles (the masses typically are located outside the perineurium) which leads to secondary axonal degeneration and nerve fiber loss. | | | The recurrent laryngeal nerve on each side is derived from the vagus nerve which in turn originates from the nucleus ambiguus in the brainstem [ 149 ]; so theoretically, a lesion in any of these anatomic locations might lead to laryngeal dysfunction. | | | Nerve involvement is most noticeable at sites such as the spinal foramina and over bony prominences, where they are susceptible to stretching and compression associated with normal vertebral movement. |
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http://www.ivis.org/special_books/Braund/braund20b/chapter_frm.asp?LA=1#Birman_Cat
(2964 words)
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| | SPINAL MOTOR STRUCTURES |
| | There are two types of nerve endings wrapped around this intrafusal fiber, both of which monitor its degree of stretch - as the muscle stretches, so does this capsule within it. | | | However, the cord can be divided into segments by the nerve roots that come off of it; although the rootlets branch off nearly continuously, they coalesce into about 31 discrete nerves along the cord (8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal nerves). | | | Although we usually study the spinal cord as a series of cross sections, it is important to remember that it is in fact a column, with continuous tracts and cell columns. |
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http://thalamus.wustl.edu/course/spinal.html
(1662 words)
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| | Nerve injuries |
| | If both the nerve and insulation have been cut and the nerve is not fixed, the growing nerve fibers may grow into a ball at the end of the cut, forming a nerve scar or neuroma. | | | When nerve fibers are cut, the end of the fiber farthest from the brain dies, while the insulation stays healthy. | | | After the nerve has recovered, the brain gets "lazy," and a procedure called sensory re-education may be needed to improve feeling to the hand or finger. |
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http://orthoinfo.aaos.org/brochure/thr_report.cfm?Thread_ID=49&topcategory=Hand
(756 words)
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| | Lecture Outline 17 |
| | Cell body of preganglionic nerve fibers is found in thoracic-lumbar region of spinal cord and terminates in a ganglia near cord; postganglionic fiber is long and innervates the organ. | | | Cell bodies of preganglionic nerve fibers arise from craniosacral part of spinal cord and have a long axon that terminates in ganglia near or within the organ. | | | Nerves are structures that contain bundles of fibers; sensory nerves contain long dendrites, motor nerves contain long axons, and mixed nerves contain both. |
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http://www.tc.cc.tx.us/~mstorey/1409/notes/lecture17.html
(1855 words)
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| | Dorlands Medical Dictionary |
| | Nerve fibers are classified on the basis of the presence or absence of a myelin sheath as myelinated or unmyelinated. | | | In the terminology for types of nerve fibers, the word nerve is frequently dropped; e.g., myelinated f's, unmyelinated f's, etc. Called also fiber, fibra, and neurofiber. | | | Vail's neuralgia, vidian neuralgia, neuralgia affecting the vidian nerve (nervus canalis pterygoidei). |
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http://www.mercksource.com/pp/us/cns/cns_hl_dorlands.jspzQzpgzEzzSzppdocszSzuszSzcommonzSzdorlandszSzdorlandzSzdmd_n_06zPzhtm
(1855 words)
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| | PSM11N |
| | 4. The preganglionic fibers arise in the cord and exit via the ventral root of the appropriate spinal nerve. | | | l. Oculomotor - Supplies fibers to the ciliary muscles (focusing) and the pupillary constrictors (light control) of the eye. | | | The afferent fibers are mixed in with somatic fibers and are therefore not anatomically distinct as are the efferent fibers. |
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http://www.accd.edu/sac/biology/ratorres/printouts/psm11n.htm
(1855 words)
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| | Chap VI |
| | A population of auditory nerve fibers, all phase-locking to the same stimulus, represent in their combined discharge pattern the complete temporal representation of the stimulus. | | | Because these auditory nerve fibers each innervate a single inner hair cell, and because the basilar membrane is itself tonotopically organized in a mechanical sense, the characteristic frequency of a nerve fiber is directly related to a location (or a 'place') along the basilar membrane. | | | The central processes of spiral ganglion neurons form the cochlear nerve and exit the temporal bone in the internal acoustic meatus. |
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http://www.neurophys.wisc.edu/h&b/textbook/chap-6.html
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| | SIU SOM Histology SSB |
| | Each fiber has a mechanosensory nerve ending (the most prominent of these are called "annulospiral endings") which wraps around the mid-region of the fiber; this sensor produces nerve impulses in response to stretch. | | | Each individual skeletal muscle fiber extends over much of the length of the muscle in which it resides (up to many centimeters), with a uniform diameter that is typically around 50 µm. | | | Motor units are small, with one or few fibers, in muscles with delicate action like those moving the fingers or eyes; they are much larger in muscles with cruder action, like those in the back or thigh. |
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http://www.siumed.edu/~dking2/ssb/muscle.htm
(3134 words)
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| | Peripheral Nerve Society |
| | The interests of our members encompass all aspects of the peripheral nervous system, both clinical and scientific, and range from electrophysiologic tools for diagnosis to molecular mechanisms of disease and nerve fiber regeneration. | | | The Peripheral Nerve Society was founded in 1994, having evolved from two groups of academic investigators interested in understanding the basic biology and function of the peripheral nervous system - the nature of nerve injury and repair. | | | is the official journal of the Peripheral Nerve Society, and publishes original research reports, case studies, reviews, letters, and news covering every topic of scientific and clinical relevance to the peripheral nervous system. |
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http://pns.ucsd.edu
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| | Directory of open access journals |
| | We concluded that in countries where leprosy is frequent, nerve biopsy is an obligatory procedure in patients with predominantly small-fiber polyneuropathy. | | | Sural nerve biopsy consisted of: 1) inflammatory infiltrates, 2) vacuolated "foamy" cells, 3) fibrosis of endoneurium, perineurium, and epineurium, 4) partial or total loss of nerve fibers, 5) large number of bacilli. | | | The tendon reflexes were normal in seven patients and in eight there was thickening of the nerves. |
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http://www.doaj.org/abstract?id=11509&toc=y
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| | Arq. Neuro-Psiquiatr. vol.62 no.2A; Abstract: S0004-282X2004000200015 |
| | Skin biopsy may be a useful tool for assessing the topographic extent and degree of nerve fiber damage in sensory neuropathies and may be particularly useful in experimental treatment trials for peripheral neuropathies since, in contrast to standard nerve biopsy, the test can be repeated. | | | : skin biopsy; small fibers; intraepidermal nerve fiber; PGP 9,5. | | | Skin biopsy has become an attractive technique to evaluate the terminal regions of small nerve fibers. |
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http://www.scielo.br/scielo.php?script=sci_abstract&pid=S0004-282X2004000200015&lng=en&nrm=iso&tlng=en
(2203 words)
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| | reflexes |
| | These nerve fibers are the largest lower motor neurons that synapse with Ia fibers inside the spinal cord (or brain stem) and end on the skeleatal muscle fibers inside the muscle. | | | Important concept that must be understood is that intrafusal fibers are miniature skeletal fibers that contract like any other muscle fibers, however due to close relationship with sensory endings their main function is related to the sensory aspect of the length of the muscle. | | | Nuclear bag and nuclear chain fibers are intrafusal muscle fibers with ability to contract similar to extrafusal muscle fibers. |
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http://www.ptd.neu.edu/mjamali/reflexes.htm
(2203 words)
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| | Peripheral Nervous System Frame |
| | cutaneous nerves: sensory fibers from the skin of the neck, ear area, and shoulder | | | Classify sensory receptors according to body location, stimulus detected, and structure and describe receptor potentials and define adaptation; compare and contrast the motor endings of somatic and autonomic nerve fibers. | | | Define nerve and describe the general structure of a nerve and distinguish between sensory, motor, and mixed nerves; describe the process of nerve fiber regeneration. |
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http://www.qeced.net/bio/hap/NervPNS.htm
(2203 words)
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| | Fitrex.com - How Muscles Work |
| | On the other hand, each of the 580 motor units in the large muscle of the calf is much bigger averaging about 2,000 muscle fibers per nerve ending. | | | Every time a nerve ending fires, a burst of energy is released in each individual muscle fiber, causing tiny filaments to slide toward each other. | | | One end, which connects to a relatively unmoving skeletal part, is the origin of the muscle. |
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http://www.fitrex.com/articles/article244.html
(529 words)
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