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Fascial Spaces Of The Head And Neck
Fascial spaces (also termed fascial tissue spaces or tissue spaces) are potential spaces that exist between the fasciae and underlying organs and other tissues. In health, these spaces do not exist; they are only created by pathology, e.g. the spread of pus or cellulitis in an infection. The fascial spaces can also be opened during the dissection of a cadaver. The fascial spaces are different from the fasciae themselves, which are bands of connective tissue that surround structures, e.g. muscles. The opening of fascial spaces may be facilitated by pathogenic bacterial release of enzymes which cause tissue lysis (e.g. hyaluronidase and collagenase). The spaces filled with loose areolar connective tissue may also be termed clefts. Other contents such as salivary glands, blood vessels, nerves and lymph nodes are dependent upon the location of the space. Those containing neurovascular tissue (nerves and blood vessels) may also be termed compartments. Generally, the spread of infection ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potential Space
In anatomy, a potential space is a space between two adjacent structures that are normally pressed together (directly apposed). Many anatomic spaces are potential spaces, which means that they are potential rather than realized (with their realization being dynamic according to physiologic or pathophysiologic events). In other words, they are like an empty plastic bag that has not been opened (two walls collapsed against each other; no interior volume until opened) or a balloon that has not been inflated. The pleural space, between the visceral and parietal pleura of the lung, is a potential space. Though it only contains a small amount of fluid normally, it can sometimes accumulate fluid or air that widens the space. The pericardial space is another potential space that may fill with fluid (effusion) in certain disease states (e.g. pericarditis; a large pericardial effusion may result in cardiac tamponade. Examples * costodiaphragmatic recess * pericardial cavity *epidural space ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nerve
A nerve is an enclosed, cable-like bundle of nerve fibers (called axons) in the peripheral nervous system. A nerve transmits electrical impulses. It is the basic unit of the peripheral nervous system. A nerve provides a common pathway for the electrochemical nerve impulses called action potentials that are transmitted along each of the axons to peripheral organs or, in the case of sensory nerves, from the periphery back to the central nervous system. Each axon, within the nerve, is an extension of an individual neuron, along with other supportive cells such as some Schwann cells that coat the axons in myelin. Within a nerve, each axon is surrounded by a layer of connective tissue called the endoneurium. The axons are bundled together into groups called fascicles, and each fascicle is wrapped in a layer of connective tissue called the perineurium. Finally, the entire nerve is wrapped in a layer of connective tissue called the epineurium. Nerve cells (often called neurons) are f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internal Maxillary Artery
The maxillary artery supplies deep structures of the face. It branches from the external carotid artery just deep to the neck of the mandible. Structure The maxillary artery, the larger of the two terminal branches of the external carotid artery, arises behind the neck of the mandible, and is at first imbedded in the substance of the parotid gland; it passes forward between the ramus of the mandible and the sphenomandibular ligament, and then runs, either superficial or deep to the lateral pterygoid muscle, to the pterygopalatine fossa. It supplies the deep structures of the face, and may be divided into mandibular, pterygoid, and pterygopalatine portions. First portion The ''first'' or ''mandibular '' or ''bony'' portion passes horizontally forward, between the neck of the mandible and the sphenomandibular ligament, where it lies parallel to and a little below the auriculotemporal nerve; it crosses the inferior alveolar nerve, and runs along the lower border of the lateral ptery ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mandibular Division Of The Trigeminal Nerve
In neuroanatomy, the mandibular nerve (V) is the largest of the three divisions of the trigeminal nerve, the fifth cranial nerve (CN V). Unlike the other divisions of the trigeminal nerve (ophthalmic nerve, maxillary nerve) which contain only afferent fibers, the mandibular nerve contains both afferent and efferent fibers. These nerve fibers innervate structures of the lower jaw and face, such as the tongue, lower lip, and chin. The mandibular nerve also innervates the muscles of mastication. Structure The large sensory root emerges from the lateral part of the trigeminal ganglion and exits the cranial cavity through the foramen ovale. Portio minor, the small motor root of the trigeminal nerve, passes under the trigeminal ganglion and through the foramen ovale to unite with the sensory root just outside the skull. The mandibular nerve immediately passes between tensor veli palatini, which is medial, and lateral pterygoid, which is lateral, and gives off a meningeal branch (ne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Masticator Space
Fascial spaces (also termed fascial tissue spaces or tissue spaces) are potential spaces that exist between the fasciae and underlying organs and other tissues. In health, these spaces do not exist; they are only created by pathology, e.g. the spread of pus or cellulitis in an infection. The fascial spaces can also be opened during the dissection of a cadaver. The fascial spaces are different from the fasciae themselves, which are bands of connective tissue that surround structures, e.g. muscles. The opening of fascial spaces may be facilitated by pathogenic bacterial release of enzymes which cause tissue lysis (e.g. hyaluronidase and collagenase). The spaces filled with loose areolar connective tissue may also be termed clefts. Other contents such as salivary glands, blood vessels, nerves and lymph nodes are dependent upon the location of the space. Those containing neurovascular tissue (nerves and blood vessels) may also be termed compartments. Generally, the spread of infection ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Odontogenic Infection
An odontogenic infection is an infection that originates within a tooth or in the closely surrounding tissues. The term is derived from '' odonto-'' (Ancient Greek: , – 'tooth') and '' -genic'' (Ancient Greek: , ; – 'birth'). The most common causes for odontogenic infection to be established are dental caries, deep fillings, failed root canal treatments, periodontal disease, and pericoronitis. Odontogenic infection starts as localised infection and may remain localised to the region where it started, or spread into adjacent or distant areas. It is estimated that 90-95% of all orofacial infections originate from the teeth or their supporting structures and are the most common infections in the oral and maxilofacial region. Odontogenic infections can be severe if not treated and are associated with mortality rate of 10 to 40%. Furthermore, about 70% of odontogenic infections occur as periapical inflammation, i.e. acute periapical periodontitis or a periapical abscess. The next m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyoid Bone
The hyoid bone (lingual bone or tongue-bone) () is a horseshoe-shaped bone situated in the anterior midline of the neck between the chin and the thyroid cartilage. At rest, it lies between the base of the mandible and the third cervical vertebra. Unlike other bones, the hyoid is only distantly articulated to other bones by muscles or ligaments. It is the only bone in the human body that is not connected to any other bones nearby. The hyoid is anchored by muscles from the anterior, posterior and inferior directions, and aids in tongue movement and swallowing. The hyoid bone provides attachment to the muscles of the floor of the mouth and the tongue above, the larynx below, and the epiglottis and pharynx behind. Its name is derived . Structure The hyoid bone is classed as an irregular bone and consists of a central part called the body, and two pairs of horns, the greater and lesser horns. Body The body of the hyoid bone is the central part of the hyoid bone. *At the fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dyspnoea
Shortness of breath (SOB), also medically known as dyspnea (in AmE) or dyspnoea (in BrE), is an uncomfortable feeling of not being able to breathe well enough. The American Thoracic Society defines it as "a subjective experience of breathing discomfort that consists of qualitatively distinct sensations that vary in intensity", and recommends evaluating dyspnea by assessing the intensity of its distinct sensations, the degree of distress and discomfort involved, and its burden or impact on the patient's activities of daily living. Distinct sensations include effort/work to breathe, chest tightness or pain, and "air hunger" (the feeling of not enough oxygen). The tripod position is often assumed to be a sign. Dyspnea is a normal symptom of heavy physical exertion but becomes pathological if it occurs in unexpected situations, when resting or during light exertion. In 85% of cases it is due to asthma, pneumonia, cardiac ischemia, interstitial lung disease, congestive heart failure, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dysphagia
Dysphagia is difficulty in swallowing. Although classified under "symptoms and signs" in ICD-10, in some contexts it is classified as a disease#Terminology, condition in its own right. It may be a sensation that suggests difficulty in the passage of solids or liquids from the mouth to the stomach, a lack of Pharynx, pharyngeal sensation or various other inadequacies of the swallowing mechanism. Dysphagia is distinguished from other symptoms including odynophagia, which is defined as painful swallowing, and Globus Pharyngis, globus, which is the sensation of a lump in the throat. A person can have dysphagia without odynophagia (dysfunction without pain), odynophagia without dysphagia (pain without dysfunction) or both together. A psychogenic disease, psychogenic dysphagia is known as phagophobia. Classification Dysphagia is classified into the following major types: # Oropharyngeal dysphagia # Esophageal dysphagia, Esophageal and obstructive dysphagia # Neuromuscular symptom comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscles Of Mastication
There are four classical muscles of mastication. During mastication, three muscles of mastication (''musculi masticatorii'') are responsible for adduction of the jaw, and one (the lateral pterygoid) helps to abduct it. All four move the jaw laterally. Other muscles, usually associated with the hyoid, such as the mylohyoid muscle, are responsible for opening the jaw in addition to the lateral pterygoid. Structure The muscles are: * The masseter (composed of the superficial and deep head) * The temporalis (the sphenomandibularis is considered a part of the temporalis by some sources, and a distinct muscle by others) * The medial pterygoid * The lateral pterygoid In humans, the mandible, or lower jaw, is connected to the temporal bone of the skull via the temporomandibular joint. This is an extremely complex joint which permits movement in all planes. The muscles of mastication originate on the skull and insert into the mandible, thereby allowing for jaw movements during contr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trismus
Trismus, commonly called ''lockjaw'' as associated with tetanus, is a condition of limited jaw mobility. It may be caused by spasm of the muscles of mastication or a variety of other causes. Temporary trismus occurs much more frequently than permanent trismus. It is known to interfere with eating, speaking, and maintaining proper oral hygiene. This interference, specifically with an inability to swallow properly, results in an increased risk of aspiration. In some instances, trismus presents with altered facial appearance. The condition may be distressing and painful. Examination and treatments requiring access to the oral cavity can be limited, or in some cases impossible, due to the nature of the condition itself. Definition Trismus is defined as painful restriction in opening the mouth due to a muscle spasm, however it can also refer to limited mouth opening of any cause. Another definition of trismus is simply a limitation of movement. Historically and commonly, the term ''lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
