perineurium


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perineurium

 [per″ĭ-noor´e-um]
the connective tissue sheath surrounding each bundle of nerve fibers (fascicle) in a peripheral nerve. adj., adj perineu´rial.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

per·i·neu·ri·um

, pl.

per·i·neu·ri·a

(per'i-nū'rē-ŭm, -rē-ă),
One of the supporting structures of peripheral nerve trunks, consisting of layers of flattened cells and collagenous connective tissue, which surround the nerve fasciculi and form the major diffusion barrier within the nerve; with the endoneurium and epineurium, composes the peripheral nerve stroma.
[L. fr. peri- + G. neuron, nerve]
Farlex Partner Medical Dictionary © Farlex 2012

perineurium

(pĕr′ə-no͝or′ē-əm, -nyo͝or′-)
n. pl. peri·neuria (-no͝or′ē-ə, -nyo͝or′-)
The sheath of connective tissue enclosing a bundle of nerve fibers.

per′i·neu′ri·al adj.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.

per·i·neu·ri·um

, pl. perineuria (per'i-nūr'ē-ŭm, -ă) [TA]
One of the supporting structures of peripheral nerve trunks, consisting of layers of flattened cells and collagenous connective tissue, which surround the nerve fasciculi and form the major diffusion barrier within the nerve; with the endoneurium and epineurium, composes the peripheral nerve stroma.
[L. fr. peri- + G. neuron, nerve]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

perineurium

A sheath of connective tissue surrounding and separating nerve fibre bundles.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005
References in periodicals archive ?
The cellular sheet made by the fibroblast-like cells were isolated from the inner cellular layer of the perineurium by the accumulated subperineurial oedema which could explain the subperineurial accumulation of the endoneurial oedema following nerve injury.
(6) Seddon Sunderland Structural and functional processes Neurapraxia 1 Myelin damage, conduction slowing, and blocking Axonotmesis 2 Loss of axonal continuity; endoneurium intact; no conduction Neurotmesis 3 Loss of axonal and endoneurial continuity; perineurium intact; no conduction 4 Loss of axonal, endoneurial, and perineurial continuity; epineurium intact; no conduction 5 Entire nerve trunk separated; no conduction
In addition, a delicate resection of the free edges of the ligament can be performed rather than simply dissecting, reducing the risk of perineurium's intrinsic fibrosis.
Within a smaller field of view it is possible to visualize anatomical details, such as the epineurium, the perineurium, and single fascicles, which otherwise would require a biopsy to be detected [15,16].
Transverse view showing breach in the perineurium of thickened nerve with hypoechoic areas suggestive of abscess formation as indicated by arrow.
The schwanoma and neurofibroma differ histologically and histogenetically; the schwannoma is derived from the Schwann cells and the neurofibroma from the fibroblasts of the perineurium. [1,2] Neurofibroma is unencapsulated consisting of a mixture of Schwann cells, perineurial cells, and endoneurial fibroblasts.
Recent studies in experimental animals have indicated that hyperglycemia stimulates the production of nitric oxide, which reacts with superoxide anion to form peroxynitrite, damaging the endothelium and perineurium. The increased ROS in the kidney, especially the superoxide radicals, react with NO to form peroxynitrite, which in turn binds to tyrosine and other protein residues, yielding highly cytotoxic compounds such as nitrotyrosine, which is a measure of ONOO- (peroxynitrite) in the renal and other vascular tissues.
The perineurium was removed from the dorsal surface of the brain to expose the OLs.
Myenteric plexus neuronal cell bodies were identified by their large size, position between the internal and external layers of smooth muscle of the muscularis externa, encapsulation by a perineurium, and their morphology.
(3) The individual axons of the nerve are surrounded by the endoneurium and subsequently bound together in fascicles by the perineurium. The individual fascicles are the smallest units of the nerve that can be manipulated with current surgical techniques.
The large peripheral nerves are composed of Schwann cell-axon complexes, supported and protected by 3 connective-tissue sheaths: endoneurium, perineurium, and epineurium.