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Semilunar Ganglion
A trigeminal ganglion (or Gasserian ganglion, or semilunar ganglion, or Gasser's ganglion) is the sensory ganglion at the base of each of the two trigeminal nerves (CN V), occupying a cavity (Meckel's cave) in the dura mater, covering the trigeminal impression near the apex of the petrous part of the temporal bone. Structure It is somewhat crescent-shaped, with its convexity directed forward: Medially, it is in relation with the internal carotid artery and the posterior part of the cavernous sinus. The motor root runs in front of and medial to the sensory root, and passes beneath the ganglion; it leaves the skull through the foramen ovale, and, immediately below this foramen, joins the mandibular nerve. The greater superficial petrosal nerve lies also underneath the ganglion. The ganglion receives, on its medial side, filaments from the carotid plexus of the sympathetic. It gives off minute branches to the tentorium cerebelli, and to the dura mater in the middle fossa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Submaxillary Ganglion
The submandibular ganglion (or submaxillary ganglion in older texts) is part of the human autonomic nervous system. It is one of four parasympathetic ganglia of the head and neck. (The others are the otic ganglion, pterygopalatine ganglion, and ciliary ganglion). Location and relations The submandibular ganglion is small and fusiform in shape. It is situated above the deep portion of the submandibular gland, on the hyoglossus muscle, near the posterior border of the mylohyoid muscle. The ganglion 'hangs' by two nerve filaments from the lower border of the lingual nerve (itself a branch of the mandibular nerve, CN V3). It is suspended from the lingual nerve by two filaments, one anterior and one posterior. Through the posterior of these it receives a branch from the chorda tympani nerve which runs in the sheath of the lingual nerve. Fibers Like other parasympathetic ganglia of the head and neck, the submandibular ganglion is the site of synapse for parasympathetic fibers and carr ... [...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 sensation from the maxilla, nasal cavity, 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 orbital fissure. It t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinal Trigeminal Nucleus
The spinal trigeminal nucleus is a nucleus in the medulla that receives information about deep/crude touch, pain, and temperature from the ipsilateral face. In addition to the trigeminal nerve (CN V), the facial (CN VII), glossopharyngeal (CN IX), and vagus nerves (CN X) also convey pain information from their areas to the spinal trigeminal nucleus. Thus the spinal trigeminal nucleus receives input from V, , [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brain Stem
The brainstem (or brain stem) is the posterior stalk-like part of the brain that connects the cerebrum with the spinal cord. In the human brain the brainstem is composed of the midbrain, the pons, and the medulla oblongata. The midbrain is continuous with the thalamus of the diencephalon through the tentorial notch, and sometimes the diencephalon is included in the brainstem. The brainstem is very small, making up around only 2.6 percent of the brain's total weight. It has the critical roles of regulating cardiac, and respiratory function, helping to control heart rate and breathing rate. It also provides the main motor and sensory nerve supply to the face and neck via the cranial nerves. Ten pairs of cranial nerves come from the brainstem. Other roles include the regulation of the central nervous system and the body's sleep cycle. It is also of prime importance in the conveyance of motor and sensory pathways from the rest of the brain to the body, and from the body ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Primary Afferents
Afferent nerve fibers are the axons (nerve fibers) carried by a sensory nerve that relay sensory information from sensory receptors to regions of the brain. Afferent projections ''arrive'' at a particular brain region. Efferent nerve fibers are carried by efferent nerves and ''exit'' a region to act on muscles and glands. In the peripheral nervous system afferent and efferent nerve fibers are part of the somatic nervous system and arise from outside of the spinal cord. Sensory nerves carry the afferent fibers to enter into the spinal cord, and motor nerves carry the efferent fibers out of the spinal cord to act on skeletal muscles. In the central nervous system non-motor efferents are carried in efferent nerves to act on glands. Structure Afferent neurons are pseudounipolar neurons that have a single process leaving the cell body dividing into two branches: the long one towards the sensory organ, and the short one toward the central nervous system (e.g. spinal cord). T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whiskers
Vibrissae (; singular: vibrissa; ), more generally called Whiskers, are a type of stiff, functional hair used by mammals to sense their environment. These hairs are finely specialised for this purpose, whereas other types of hair are coarser as tactile sensors. Although whiskers are specifically those found around the face, vibrissae are known to grow in clusters at various places around the body. Most mammals have them, including all non-human primates and especially nocturnal mammals. Whiskers are sensitive tactile hairs that aid navigation, locomotion, exploration, hunting, social touch and perform other functions. This article is primarily about the specialised sensing hairs of mammals, but some birds, fish, insects, crustaceans and other arthropods are known to have similar structures also used to sense the environment. Etymology Vibrissae (from Latin 'to vibrate') from the characteristic motion seen in a small rodent that is otherwise sitting still. In medicine, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trigeminal Neuralgia
Trigeminal neuralgia (TN or TGN), also called Fothergill disease, tic douloureux, or trifacial neuralgia is a long-term pain disorder that affects the trigeminal nerve, the nerve responsible for sensation in the face and motor functions such as biting and chewing. It is a form of neuropathic pain. There are two main types: typical and atypical trigeminal neuralgia. The typical form results in episodes of severe, sudden, shock-like pain in one side of the face that lasts for seconds to a few minutes. Groups of these episodes can occur over a few hours. The atypical form results in a constant burning pain that is less severe. Episodes may be triggered by any touch to the face. Both forms may occur in the same person. It is regarded as one of the most painful disorders known to medicine, and often results in depression. The exact cause is unknown, but believed to involve loss of the myelin of the trigeminal nerve. This might occur due to compression from a blood vessel as the ne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycerol
Glycerol (), also called glycerine in British English and glycerin in American English, is a simple triol compound. It is a colorless, odorless, viscous liquid that is sweet-tasting and non-toxic. The glycerol backbone is found in lipids known as glycerides. Because it has antimicrobial and antiviral properties, it is widely used in wound and burn treatments approved by the U.S. Food and Drug Administration. Conversely, it is also used as a bacterial culture medium. It can be used as an effective marker to measure liver disease. It is also widely used as a sweetener in the food industry and as a humectant in pharmaceutical formulations. Because of its three hydroxyl groups, glycerol is miscible with water and is hygroscopic in nature. Structure Although achiral, glycerol is prochiral with respect to reactions of one of the two primary alcohols. Thus, in substituted derivatives, the stereospecific numbering labels the molecule with a "sn-" prefix before the stem name of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trigeminal Trophic Syndrome
Trigeminal trophic syndrome is a rare disease caused by the interruption of peripheral or central sensory pathways of the trigeminal nerve. A slowly enlarging, uninflammed ulcer can occur in the area that has had trigeminal nerve damage; including but not limited to the cheek beside the ala nasi. These sores affect the skin supplied by the sensory component of the trigeminal nerve. Similar lesions may also occur in the corners of the eyes, inside the ear canal, on the scalp or inside the mouth. It has been stated that the ulceration is due to the constant "picking" of the patient. While this does occur, the picking behavior is an incomplete explanation of the disease presentation: the lack of feeling or pain allows the patient to continue scratching or picking the area, and, although there is no feeling, there is constant neuropathic pain. Sixty cases were reported from 1982 to 2002. See also * Trigeminal neuralgia (Tic douloureux) * Skin lesion * List of cutaneous conditions * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viral Latency
Virus latency (or viral latency) is the ability of a pathogenic virus to lie dormant (latent) within a cell, denoted as the lysogenic part of the viral life cycle. A latent viral infection is a type of persistent viral infection which is distinguished from a chronic viral infection. Latency is the phase in certain viruses' life cycles in which, after initial infection, proliferation of virus particles ceases. However, the viral genome is not eradicated. The virus can reactivate and begin producing large amounts of viral progeny (the lytic part of the viral life cycle) without the host becoming reinfected by new outside virus, and stays within the host indefinitely. Virus latency is not to be confused with clinical latency during the incubation period when a virus is ''not'' dormant. Mechanisms Episomal latency Episomal latency refers to the use of genetic episomes during latency. In this latency type, viral genes are stabilized, floating in the cytoplasm or nucleus as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
