dural sheath


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sheath

 [shēth]
a tubular case or envelope.
arachnoid sheath the delicate membrane between the pial sheath and the dural sheath of the optic nerve.
carotid sheath a portion of the cervical fascia enclosing the carotid artery, internal jugular vein, vagus nerve, and sympathetic nerves supplying the head.
connective tissue sheath of Key and Retzius endoneurium.
crural sheath femoral sheath.
dural sheath the external investment of the optic nerve.
femoral sheath the fascial sheath of the femoral vessels.
Henle's sheath endoneurium.
lamellar sheath the perineurium.
medullary sheath myelin sheath.
myelin sheath (nerve sheath) the sheath surrounding the axon of myelinated nerve cells, consisting of concentric layers of myelin formed in the peripheral nervous system by the plasma membrane of Schwann cells, and in the central nervous system by the plasma membrane of oligodendrocytes. It is interrupted at intervals along the length of the axon by gaps known as nodes of Ranvier. Myelin is an electrical insulator that serves to speed the conduction of nerve impulses (see saltatory conduction).
pial sheath the innermost of the three sheaths of the optic nerve.
root sheath the epidermic layer of a hair follicle.
sheath of Schwann neurilemma.
synovial sheath synovial membrane lining the cavity of a bone through which a tendon moves.
tendon sheath a lubricated fibrous or synovial layer of tissue in which the tendon is housed and through which it moves.

du·ral sheath

an extension of the dura mater that ensheathes the roots of spinal nerves or, more particularly, the vagina externa nervi optici.

dural sheath

an extension of the dura mater covering the optic nerve and spinal nerve roots.

du·ral sheath

(dūr'ăl shēth)
An extension of the dura mater that ensheathes the roots of spinal nerves or, more particularly, the vagina externa nervi optici.

sheath

1. a tubular case or envelope.
2. vernacular for prepuce.

adrenal pericapsular sheath
contains a plexus of large nerve trunks with numerous ganglion cells.
arachnoid sheath
the delicate membrane between the pial sheath and the dural sheath of the optic nerve.
carotid sheath
a portion of the cervical fascia enclosing the carotid artery, internal jugular vein, and vagus or vagosympathetic nerve.
carpal tendon s's
sheaths to the tendons of the muscles which course over the carpus.
crural sheath
femoral sheath.
dural sheath
the external investment of the optic nerve.
femoral sheath
the fascial sheath of the femoral vessels.
Henle's sheath
the endoneurium, especially the delicate continuation around the terminal branches of nerve fibers.
lamellar sheath
the perineurium.
medullary sheath, myelin sheath
the sheath surrounding the axon of myelinated nerve cells, consisting of concentric layers of myelin formed in the peripheral nervous system by the plasma membrane of Schwann cells, and in the central nervous system by the plasma membrane of oligodendrocytes. It is interrupted at intervals along the length of the axon by gaps known as nodes of Ranvier. Myelin is an electrical insulator that serves to speed the conduction of nerve impulses.
pial sheath
the innermost of the three sheaths of the optic nerve.
root sheath
the epidermal layer of a hair follicle.
sheath of Schwann
neurilemma.
synovial sheath
a synovial membrane sleeve through which a tendon moves; found commonly where a tendon passes over a joint.