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.

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]

perineurium

/peri·neu·ri·um/ (-noor´e-um) an intermediate layer of connective tissue in a peripheral nerve, surrounding each bundle of nerve fibers.perineu´rial

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.

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]

perineurium

A sheath of connective tissue surrounding and separating nerve fibre bundles.

perineurium

the connective tissue sheath surrounding each bundle (fascicle) of nerve fibers in a peripheral nerve.
References in periodicals archive ?
In Grade 4, axonal degeneration is coupled with loss of endoneurium, perineurium, and nerve fiber continuity; spontaneous recovery becomes less likely due to scarring (Table 1).
Reorganization and orientation of regenerating nerve fibres, perineurium, and epineurium in preformed mesothelial tubes--an experimental study on the sciatic nerve of rats.
The neuroma is composed of a partially encapsulated aggregation or proliferation of nerves, often with thickened perineurium, intertwined with one another in a plexiform pattern.
3) Tarlov cysts are rare and arise from the perineurium membrane surrounding the spinal nerve root, near the dorsal root ganglion.
If the injury is recognized intraoperatively, most surgeons advocate primary reapproximation of the perineurium using non-absorbable sutures.
Amyloid deposits were present in the perineurium, endoneurium, and endoneurial arterioles in two patients (1 and 4), and only in a single endoneurial arterioles in one patient (2).
According to previous reports, PNI was determined as positive when cancer cells infiltrated into the perineurium or neural fasciculus intramurally.
All nerve biopsies displayed inflammatory cell infiltrate with vacuolated cells, fibrosis of the perineurium, endoneurium and endoneural vessels (Figure 1, Table 3).
6) More recently, investigators have proposed that malignant cells invade and spread via potential spaces in the connective tissue planes of the perineurium and endoneurium without inciting an inflammatory response in the surrounding stroma or invading the nerve fibers themselves.
The intrinsic (internal) longitudinal system is located within the perineurium and endoneurium.
Various cadaver studies (11) demonstrated that the dye injected under the perineurium of one branch eventually reaches the other if the volume of the dye was relatively high.