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Related to occipital nerve: lesser occipital nerve, third occipital nerve


see nervous systemnervous system,
network of specialized tissue that controls actions and reactions of the body and its adjustment to the environment. Virtually all members of the animal kingdom have at least a rudimentary nervous system.
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the cordlike association of nerve tissues that links the brain and nerve ganglia by innervation to the other organs and tissues of the body.

A nerve primarily consists of nerve fibers. In vertebrates many nerves converge to form a bundle that is surrounded by a connective tissue sheath, the perineurium; the thin interstitial layers of connective tissue that separate the individual fibers deep within the bundle constitute the endoneurium. Finally, the entire nerve trunk, comprising several bundles, is covered by an additional sheath, the epineurium.

Nerves can be sensory (also called afferent or centripetal) or motor (also called efferent or centrifugal). Some nerves, for example, those innervating the skeletal muscles, mainly include myelinated, or medullated, fibers; others, for example, the sympathetic nerves, largely consist of unmyelinated, or unmedullated, fibers.

In reptiles, birds, mammals, and man 12 pairs of cranial nerves branch from the brain: the olfactory (cranial nerve I), the optic (cranial nerve II), the oculomotor (cranial nerve III), the trochlear (cranial nerve IV), the trigeminal (cranial nerve V), the abducent (cranial nerve VI), the facial (cranial nerve VII), the acoustic (cranial nerve VIII), the glossopharyngeal (cranial nerve IX), the vagus (cranial nerve X), the accessory (cranial nerve XI), and the hypoglossal (cranial nerve XII). Only the first ten pairs are present in fish and amphibians.

In man there are 31 pairs of spinal nerves: eight cervical, 12 thoracic, five lumbar, five sacral, and one coccygeal. Each pair innervates the effectors and receptors of a certain part of the body. The spinal nerves branch from the spinal cord into two roots—the posterior, or sensory, and the anterior, or motor. Both roots then combine to form a common trunk that consists of both sensory and motor fibers.

Several adjacent nerves can be combined into nerve plexuses, where an exchange of fibers between different nerves can take place. Three large plexuses are distinguished: the cervical, the brachial, and the lumbosacral. Each nerve plexus is the origin of several pairs of nerves; for example, the sacral portion of the lumbosacral plexus gives rise to the sciatic nerves.

Nerves that originate in the ganglia, trunks, and plexuses of the autonomic nervous system constitute a specific group. The optic nerve is remarkable for its large number of fibers; there are more than 1 million in the human optic nerve. Usually, however, there are 103 -104 fibers in a nerve. In invertebrates certain nerves are known to consist of only a few fibers. The peripheral nervous system in animals and man consists of aggregations of nerves.



A bundle of nerve fibers or processes held together by connective tissue.


Any one of the ribs of a groined vault, but esp. a rib which forms one of the sides of a compartment of the groining.


1. any of the cordlike bundles of fibres that conduct sensory or motor impulses between the brain or spinal cord and another part of the body
2. a large vein in a leaf
3. any of the veins of an insect's wing
References in periodicals archive ?
032 mm gauge introducer needle (Model 1114) was inserted with a right medial-lateral approach, following the transverse occipital curvature and avoiding overshooting the superficial muscular fascia, for safe placement of the electrodes over the occipital nerves.
2,6,7,25) Briefly expanding on these ITs, injection or infiltration of the greater occipital nerve or lesser occipital nerve with anaesthetic (i.
Conclusions: For patients with PDPH and a pre-block VAS score between 4 and 6 who do not respond to conservative medical treatment an ultrasound-guided bilateral occipital nerve block may be effective.
Often though, we see it manifested after physical insult to the greater or lesser occipital nerve pathways i.
We believe the combination of prolonged immobility and compression of the occipital nerves between the bony superior nuchal ridge and the head rest are the most likely aetiology.
The leads create an electric field on the occipital nerves, located in the back of the head, and the patient uses a hand-held computer to activate the generator and control the intensity and frequency of the electrical stimulation.
The exclusion criteria were as follows: previous occipital nerve block or occipital nerve stimulation, a history of occipital region surgery, a history of allergic reaction to the local anesthetic to be applied, pregnancy and breastfeeding, existing active psychiatric disease, uncontrolled hypertension, uncontrolled diabetes mellitus, decompensated congestive heart failure, chronic renal failure, chronic liver disease, tumor and/ or the presence of vascular disease, any existing inflammatory and/or infectious disease, and the use of anticoagulants.
Ultrasound-guided Pulsed Radiofrequency of the Third Occipital Nerve.
It has been proposed that the clinical benefit for temporal placement may be based on coverage of the terminal branches of the trigeminal nerves, along with the communicating branches between the auriculotemporal nerve and the lesser occipital nerve.
New invasive procedures, such as hypothalamic deep brain stimulation and bilateral occipital nerve stimulation, may help patients with chronic refractory headache.
Doctors also are not sure how the occipital nerve stimulators stop the headaches but they think that the stimulator modifies the abnormal activity.
BOSTON -- The efficacy of occipital nerve stimulation in the first clinical trial of its use in the treatment of refractory migraines suggests that the technique may be a promising option for individuals who have not responded to medication or other established therapies, according to Dr.