|
Deep Petrosal Nerve
The deep petrosal nerve is a post-ganglionic branch of the ( sympathetic) internal carotid (nervous) plexus (which is in turn derived from the superior cervical ganglion, a part of the cervical sympathetic trunk) that enters the cranial cavity through the carotid canal, then passes perpendicular to the carotid canal in the cartilaginous substance which fills the foramen lacerum to unite with the (parasympathetic) greater petrosal nerve to form the nerve of pterygoid canal (Vidian nerve). Anatomy intermediate grey column (of spinal cord at around the level of T1) → white rami communicantes (of cervical part of sympathetic chain) → superior cervical ganglion (synapse) → gray rami communicantes → internal carotid plexus → deep petrosal nerve → nerve of pterygoid canal → pterygopalatine ganglion (fibres pass through without synapsing) → zygomatic nerve → zygomaticotemporal nerve → lacrimal nerve Origin The cell bodies of pre-ganglionic sympathetic axons th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maxillary Nerve
In neuroanatomy, the maxillary nerve (V) is one of the three branches or divisions of the trigeminal nerve, the fifth (CN V) cranial nerve. It comprises the principal functions of Sense, sensation from the maxilla, nasal cavity, Sinus (anatomy), sinuses, the palate and subsequently that of the mid-face, and is intermediate, both in position and size, between the ophthalmic nerve and the mandibular nerve.Illustrated Anatomy of the Head and Neck, Fehrenbach and Herring, Elsevier, 2012, page 180 Structure It begins at the middle of the trigeminal ganglion as a flattened plexiform band then it passes through the lateral wall of the cavernous sinus. It leaves the skull through the foramen rotundum, where it becomes more cylindrical in form, and firmer in texture. After leaving foramen rotundum it gives two branches to the pterygopalatine ganglion. It then crosses the pterygopalatine fossa, inclines lateralward on the back of the maxilla, and enters the orbit through the inferior orb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
White Ramus Communicans
The white ramus communicans (: rami communicantes) from Latin ramus (branch) and communicans (communicating) is the preganglionic sympathetic outflow nerve tract from the spinal cord. Each of the thoracic, and the first and second lumbar nerves contribute a white ramus communicans to the adjoining sympathetic ganglion, unlike the gray rami which are located at each spinal level. White rami communicantes contain both myelinated and unmyelinated preganglionic sympathetic fibers, ( GVE and GVA). The white ramus appears white because there are more myelinated than unmyelinated fibers unlike the gray rami. Structure The white rami communicantes are the preganglionic sympathetic outflow from the spinal cord. The cell bodies for the preganglionic sympathetic myelinated fibers in the white rami communicantes lie in the ipsilateral (same sided) intermediolateral cell column in the spinal cord which extends from T1-L2. These rami also contain general visceral afferent fibers (sensory ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blood Vessels
Blood vessels are the tubular structures of a circulatory system that transport blood throughout many animals’ bodies. Blood vessels transport blood cells, nutrients, and oxygen to most of the tissues of a body. They also take waste and carbon dioxide away from the tissues. Some tissues such as cartilage, epithelium, and the lens and cornea of the eye are not supplied with blood vessels and are termed ''avascular''. There are five types of blood vessels: the arteries, which carry the blood away from the heart; the arterioles; the capillaries, where the exchange of water and chemicals between the blood and the tissues occurs; the venules; and the veins, which carry blood from the capillaries back towards the heart. The word ''vascular'', is derived from the Latin ''vas'', meaning ''vessel'', and is mostly used in relation to blood vessels. Etymology * artery – late Middle English; from Latin ''arteria'', from Greek ''artēria'', probably from ''airein'' ("raise ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lateral Grey Column
The lateral grey column (lateral column, lateral cornu, lateral horn of spinal cord, intermediolateral column) is one of the three grey columns of the spinal cord (which give the shape of a butterfly); the others being the anterior grey column, anterior and posterior grey column, posterior grey columns. The lateral grey column is primarily involved with activity in the Sympathetic nervous system, sympathetic division of the Autonomic nervous system, autonomic Motor nerve, motor system. It projects to the side as a triangular field in the thoracic and upper lumbar regions (specifically thoracic vertebrae, T1-lumbar vertebrae, L2) of the postero-lateral part of the anterior grey column. Background information Nervous system The nervous system is the system of neurons, or nerve cells that relay electrical signals through the brain and body. A nerve cell receives signals from other nerve cells through tree-branch-like extensions called dendrites and passes signals through a long ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lacrimal Nerve
The lacrimal nerve is the smallest of the three main branches of the ophthalmic nerve (CN V1) (itself a branch of the trigeminal nerve (CN V)). It enters the orbit outside the common tendinous ring and passes forward along the side wall of the orbit. It provides sensory innervation to the skin and both surfaces of conjunctiva at the lateral portion of the upper eyelid. It also receives a parasympathetic secretomotor communicating branch for the lacrimal gland which it conveys to the gland. Structure Origin The lacrimal nerve branches from the ophthalmic nerve immediately before traveling through the superior orbital fissure to enter the orbit. At the superior portion of the lateral wall of the orbit, it also receives a secretomotor communicating parasympathetic branch from the zygomaticotemporal nerve for the lacrimal gland. Course It enters the orbit through the superior orbital fissure outside (lateral to) the common tendinous ring, coursing lateral to the front ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zygomaticotemporal Nerve
The zygomaticotemporal nerve (zygomaticotemporal branch, temporal branch) is a cutaneous ( sensory) nerve of the head. It is a branch of the zygomatic nerve (itself a branch of the maxillary nerve (CN V2)). It arises in the orbit and exits the orbit through the zygomaticotemporal foramen in the zygomatic bone to enter the temporal fossa. It is distributed to the skin of the side of the forehead. It also contains a parasympathetic secretomotor component for the lacrimal gland which it confers to the lacrimal nerve (which then delivers it to the gland). Structure Origin The zygomaticotemporal nerve is a branch of the zygomatic nerve. Course It passes along the lateral wall of the orbit in a groove in the zygomatic bone. It passes through the zygomaticotemporal foramen of the zygomatic bone to emerge (at the anterior portion of) the temporal fossa. In the temporal fossa, it passes superior-ward between the two layers of the temporal fascia, between the temporal bone an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zygomatic Nerve
The zygomatic nerve is a branch of the maxillary nerve (itself a branch of the trigeminal nerve (CN V)). It arises in the pterygopalatine fossa and enters the orbit through the inferior orbital fissure before dividing into its two terminal branches: the zygomaticotemporal nerve and zygomaticofacial nerve. Through its branches, the zygomatic nerve provides sensory invervation to skin over the zygomatic bone and the temporal bone. It also carries post-ganglionic parasympathetic axons to the lacrimal gland. It may be blocked by anaesthetising the maxillary nerve. Structure Origin The zygomatic nerve is a branch of the maxillary nerve (CN V2). It arises at the pterygopalatine ganglion. Course It exits from the pterygopalatine fossa through the inferior orbital fissure to enter the orbit. In the orbit, it travels anteriorly along its lateral wall. Branches Soon after the zygomatic nerve enters the orbit, it divides into its branches. These include: * Zygomaticotemporal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pterygopalatine Ganglion
The pterygopalatine ganglion (aka Meckel's ganglion, nasal ganglion, or sphenopalatine ganglion) is a parasympathetic ganglion in the pterygopalatine fossa. It is one of four parasympathetic ganglia of the head and neck, (the others being the submandibular, otic, and ciliary ganglion). It is innervated by the Vidian nerve (formed by the greater superficial petrosal nerve branch of the facial nerve and deep petrosal nerve) and maxillary division of the trigeminal nerve. Its postsynaptic axons project to the lacrimal glands and nasal mucosa. The flow of blood to the nasal mucosa, in particular the venous plexus of the conchae, is regulated by the pterygopalatine ganglion and heats or cools the air in the nose. Structure The pterygopalatine ganglion (of Meckel), the largest of the parasympathetic ganglia associated with the branches of the maxillary nerve, is deeply placed in the pterygopalatine fossa, close to the sphenopalatine foramen. It is triangular or heart-shaped ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nerve Of Pterygoid Canal
The nerve of the pterygoid canal (Vidian nerve) is formed by the union of the (parasympathetic) greater petrosal nerve and (sympathetic) deep petrosal nerve within the cartilaginous substance filling the foramen lacerum. From the foramen lacerum, the nerve of the pterygoid canal passes through the pterygoid canal to reach the pterygopalatine fossa, ending at the pterygopalatine ganglion. Structure The nerve of the pterygoid canal forms from the junction of the greater petrosal nerve and the deep petrosal nerve within the foreamen lacerum. This combined nerve exits the foramen lacerum and travels to the pterygopalatine fossa through the pterygoid canal in the sphenoid. The nerve of the pterygoid canal contains axons of both sympathetic and parasympathetic axons, specifically; *preganglonic parasympathetic axons from the greater petrosal nerve, a branch of the facial nerve (cell bodies are located in the superior salivatory nucleus) *postganglionic sympathetic axons from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gray Ramus Communicans
Each spinal nerve receives a branch called a gray ramus communicans (: rami communicantes) from the adjacent paravertebral ganglion of the sympathetic trunk. The gray rami communicantes contain postganglionic nerve fibers of the sympathetic nervous system and are composed of largely unmyelinated neurons. This is in contrast to the white rami communicantes, in which heavily myelinated neurons give the rami their white appearance. Function Preganglionic sympathetic fibers from the intermediolateral nucleus in the lateral grey column of the spinal cord are carried in the white ramus communicans to the paravertebral ganglia of the sympathetic trunk. Once the preganglionic nerve has traversed a white ramus communicans, it can do one of three things. * The preganglionic neuron can synapse with a postganglionic sympathetic neuron in the sympathetic paravertebral ganglion at that level. From here, the postganglionic sympathetic neuron can travel back out the grey ramus communicans of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sympathetic Chain
The sympathetic trunk (sympathetic chain, gangliated cord) is a paired bundle of nerve fibers that run from the base of the skull to the coccyx. It is a major component of the sympathetic nervous system. Structure The sympathetic trunk lies just lateral to the vertebral bodies for the entire length of the vertebral column. It interacts with the anterior ramus of spinal nerve, anterior rami of spinal nerves by way of rami communicantes. The sympathetic trunk permits preganglionic fibers of the sympathetic nervous system to ascend to spinal levels superior to T1 and descend to spinal levels inferior to L2/3.Greenstein B., Greenstein A. (2002): Color atlas of neuroscience – Neuroanatomy and neurophysiology. Thieme, Stuttgart – New York, . The superior end of it is continued upward through the carotid canal into the skull, and forms a plexus on the internal carotid artery; the inferior part travels in front of the coccyx, where it converges with the other trunk at a structure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intermediate Grey Horn
The lateral grey column (lateral column, lateral cornu, lateral horn of spinal cord, intermediolateral column) is one of the three grey columns of the spinal cord (which give the shape of a butterfly); the others being the anterior and posterior grey columns. The lateral grey column is primarily involved with activity in the sympathetic division of the autonomic motor system. It projects to the side as a triangular field in the thoracic and upper lumbar regions (specifically T1- L2) of the postero-lateral part of the anterior grey column. Background information Nervous system The nervous system is the system of neurons, or nerve cells that relay electrical signals through the brain and body. A nerve cell receives signals from other nerve cells through tree-branch-like extensions called dendrites and passes signals through a long extension called an axon (or nerve fiber). Synapses are places where one cell's axon passes information to another cell's dendrite by sending chemi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
