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(1 to 10 of 374 matches)
E. coli
Short for Escherichia coli, the colon bacillus, a bacterium that normally resides in the human colon. E. coli has been studied intensively in genetics and molecular and cell biology because of its availability, its small genome size, its normal lack of pathogenicity (disease-causing ability), and its ease of growth in the laboratory.
Eagle syndrome
Inflammation of the styloid process, a spike-like projection sticking off the base of the skull. The tissues in the throat rub on this structure during the act of swallowing causing pain. The diagnosis of Eagle syndrome is made by history and an x-ray showing the abnormal styloid process.
Anti-inflammatory drugs are the first line of treatment although surgical removal of the styloid process may be needed.
Ear
The hearing organ. There are three sections of the ear, according to the anatomy textbooks. They are the outer ear (the part we see along the sides of our head behind the temples), the middle ear, and the inner ear. But in terms of function, the ear has four parts: those three and the brain. Hearing thus involves all parts of the ear as well as the auditory cortex of the brain. The external ear helps concentrate the vibrations of air on the ear drum and make it vibrate. These vibrations are transmitted by a chain of little bones in the middle ear to the inner ear. There they stimulate the fibers of the auditory nerve to transmit impulses to the brain.
•The outer ear looks complicated but it is the simplest part of the ear. It consists of the pinna or auricle (the visible projecting portion of the ear), the external acoustic meatus (the outside opening to the ear canal), and the external ear canal that leads to the ear drum. In sum, there is the pinna, the meatus and the canal. That's all. And the external ear has only to concentrate air vibrations on the ear drum and make the drum vibrate.
•The middle ear consists of the ear drum (the tympanum or tympanic membrane) and, beyond it, a cavity. This cavity is connected via a canal (the Eustachian tube) to the pharynx (the nasopharynx). The Eustachian tube permits the gas pressure in the middle ear cavity to adjust to external air pressure (so, as you're descending in a plane, it's the Eustachian tube that opens when your ears "open").) The middle ear cavity also contains a chain of 3 little bones (ossicles) that connect the ear drum to the internal ear. The ossicles are named (not the Nina, the Pinta and the Santa Maria but) the malleus, incus, and stapes. In sum, the middle ear communicates with the pharynx, equilibrates with external pressure and transmits the ear drum vibrations to the inner ear.
•The internal ear is highly complex. The essential component of the inner ear for hearing is the membranous labyrinth where the fibers of the auditory nerve (the nerve connecting the ear to the brain) end. The membranous labyrinth is a system of communicating sacs and ducts (tubes) filled with fluid (the endolymph). The membranous labyrinth is lodged within a cavity called the bony labyrinth. At some points the membranous labyrinth is attached to the bony labyrinth and at other points the membraneous labyrinth is suspended in a fluid (the perilymph) within the bony labyrinth. The bony labyrinth has three parts: a central cavity (the vestibule), semicircular canals (which open into the vestible) and the cochlea (a snail-shaped spiral tube). The membranous labyrinth also has a vestibule which consists of two sacs (called the utriculus and sacculus) connected by a narrow tube. The utriculus, the larger of the two sacs, is the principal organ of the vestibular system (which informs us about the position and movement of the head). The smaller of the two sacs, the sacculus (literally, the little sac) is connected with a membranous tube in the cochlea containing the organ of Corti. It is in the organ of Corti that are situated the hair cells, the special sensory receptors for hearing.
Ear canal, self-cleaning
Most of the time the ear canals are self-cleaning, that is, there is a slow and orderly migration of ear canal skin from the eardrum to the outer opening. Old earwax is constantly being transported from the deeper areas of the ear canal to the opening where it usually dries, flakes, and falls out.
Ear cleaning (by a doctor)
When so much wax accumulates that it blocks the ear canal (and hearing), your physician may have to wash it out, vacuum it, or remove it with special instruments. Alternatively, your physician may prescribe ear drops what are designed to soften the wax (such as Cerumenex).
Ear cleaning (yourself)
Never put anything smaller than your elbow in your ear! Wax is not formed in the deep part of the ear canal near the eardrum, but only in the outer part of the canal. So when a patient has wax pushed up against the eardrum, it is often because he has been probing his ear with such things as cotton-tipped swabs (such as Q-Tips), bobby pins, or twisted napkin corners. Such objects only serve as ramrods to push the wax in deeper. Also, the skin of the ear canal and the eardrum is very thin, fragile and easily injured. The ear canal is more prone to infection after it has been whipped clean of the "good" coating type wax. In addition, we have seen many perforated eardrums as a result of these efforts.
Ear infection, middle (acute)
Acute middle ear infection, medically called acute otitis media is inflammation of the middle ear. Acute otitis media typically causes fluid in the middle ear accompanied by signs or symptoms of ear infection: a bulging eardrum usually accompanied by pain; or a perforated eardrum, often with drainage of purulent material (pus).
Otitis media is the most frequent diagnosis in sick children in the U.S., especially affecting infants and preschoolers. Almost all children have one or more bouts of otitis media before age 6.
The eustachian tube is shorter in children than adults which allows easy entry of bacteria and viruses into the middle ear, resulting in acute otitis media. Bacteria such as Streptococcus pneumoniae (strep) and Hemophilus influenzae (H. flu) account for about 85% of cases of acute otitis media and viruses the remaining 15%. Babies under 6 weeks of age tend to have infections from different bacteria in the middle ear.
Bottlefeeding is a risk factor for otitis media. Breastfeeding passes immunity to the baby that helps prevent acute otitis media. The position of the breastfeeding child is better than the bottle-feeding position for eustachian tube function. If a child needs to be bottle-fed, holding the infant rather than allowing the child to lie down with the bottle is best. A child should not take the bottle to bed. (Falling asleep with milk in the mouth increases the incidence of tooth decay).
Upper respiratory infections are a prominent risk factor for acute otitis media so exposure to groups of children as in child-care centers results in more frequent colds and therefore more earaches. Irritants such as tobacco smoke in the air also increase the chance of otitis media. Children with cleft palate or Down syndrome are predisposed to ear infections. Children who have acute otitis media before 6 months of age have more frequent later ear infections.
Young children with otitis media may be irritable, fussy, or have problems feeding or sleeping. Older children may complain about pain and fullness in the ear. Fever may be present in a child of any age. These symptoms are often associated with signs of upper respiratory infection such as a runny or stuffy nose or a cough.
The buildup of pus within the middle ear causes pain and dampens the vibrations of the eardrum (so there is usually transient hearing loss during the infection). Severe ear infections may cause the eardrum to rupture. The pus then drains from the middle ear into the ear canal. The hole in the eardrum from the rupture usually heals with medical treatment.
The treatment for acute otitis media is antibiotics usually for 7-10 days. About 10% of children do not respond within the first 48 hours of treatment. Even after antibiotic treatment, 40% of children are left with some fluid in the middle ear which can cause temporary hearing loss lasting for up to 3-6 weeks. In most children, the fluid eventually disappears (resorbs) spontaneously (on its own). Children who have recurring bouts of otitis media may have a tympanostomy tube (ear tube) placed into the ear during surgery to permit fluid to drain from the middle ear. If a child has a bulging eardrum and is experiencing severe pain, a myringotomy (surgical incision of the eardrum) to release the pus may be done. The eardrum usually heals within a week.
Acute otitis media is not contagious (although the cold that preceded it may be). A child with otitis media can travel by airplane but, if the eustachian tube is not functioning well, changes in pressure (such as in a plane) can cause discomfort. A child with a draining ear should, however, not fly (or swim).Acute middle ear infection, medically called acute otitis media is inflammation of the middle ear. Acute otitis media typically causes fluid in the middle ear accompanied by signs or symptoms of ear infection: a bulging eardrum usually accompanied by pain; or a perforated eardrum, often with drainage of purulent material (pus).
Otitis media is the most frequent diagnosis in sick children in the U.S., especially affecting infants and preschoolers. Almost all children have one or more bouts of otitis media before age 6.
The eustachian tube is shorter in children than adults which allows easy entry of bacteria and viruses into the middle ear, resulting in acute otitis media. Bacteria such as Streptococcus pneumoniae (strep) and Hemophilus influenzae (H. flu) account for about 85% of cases of acute otitis media and viruses the remaining 15%. Babies under 6 weeks of age tend to have infections from different bacteria in the middle ear.
Bottlefeeding is a risk factor for otitis media. Breastfeeding passes immunity to the baby that helps prevent acute otitis media. The position of the breastfeeding child is better than the bottle-feeding position for eustachian tube function. If a child needs to be bottle-fed, holding the infant rather than allowing the child to lie down with the bottle is best. A child should not take the bottle to bed. (Falling asleep with milk in the mouth increases the incidence of tooth decay).
Upper respiratory infections are a prominent risk factor for acute otitis media so exposure to groups of children as in child-care centers results in more frequent colds and therefore more earaches. Irritants such as tobacco smoke in the air also increase the chance of otitis media. Children with cleft palate or Down syndrome are predisposed to ear infections. Children who have acute otitis media before 6 months of age have more frequent later ear infections.
Young children with otitis media may be irritable, fussy, or have problems feeding or sleeping. Older children may complain about pain and fullness in the ear. Fever may be present in a child of any age. These symptoms are often associated with signs of upper respiratory infection such as a runny or stuffy nose or a cough.
The buildup of pus within the middle ear causes pain and dampens the vibrations of the eardrum (so there is usually transient hearing loss during the infection). Severe ear infections may cause the eardrum to rupture. The pus then drains from the middle ear into the ear canal. The hole in the eardrum from the rupture usually heals with medical treatment.
The treatment for acute otitis media is antibiotics usually for 7-10 days. About 10% of children do not respond within the first 48 hours of treatment. Even after antibiotic treatment, 40% of children are left with some fluid in the middle ear which can cause temporary hearing loss lasting for up to 3-6 weeks. In most children, the fluid eventually disappears (resorbs) spontaneously (on its own). Children who have recurring bouts of otitis media may have a tympanostomy tube (ear tube) placed into the ear during surgery to permit fluid to drain from the middle ear. If a child has a bulging eardrum and is experiencing severe pain, a myringotomy (surgical incision of the eardrum) to release the pus may be done. The eardrum usually heals within a week.
Acute otitis media is not contagious (although the cold that preceded it may be). A child with otitis media can travel by airplane but, if the eustachian tube is not functioning well, changes in pressure (such as in a plane) can cause discomfort. A child with a draining ear should, however, not fly (or swim).
Ear piercing
The practice of using a needle or needle gun to make holes through the ear lobe or other parts of the ear for wearing jewelry. When done under hygienic conditions, there is little danger from ear piercing other than localized and transitory inflammation. Unhygienic conditions, handling the new piercing with unwashed hands, or the use of irritating jewelry can result in inflammation and/or infection. Infected ear piercings should be washed and then treated with antibiotic cream. One may choose to either allow the piercing to close or to use only non-irritating jewelry (usually gold or hypoallergenic plastic). The likelihood of inflammation and infection is greater for piercings that go through hard cartilage, as found on the side and top of the outer ear, than with the soft bottom lobe of the ear.
Ear pit
Tiny pit in front of the ear: preauricular pit. A minor anomaly of no great consequence in itself. More common in blacks than whites and in females than males. Can recur in families. The presence of 2 or more minor anomalies in a child increases the probability that the child has a major malformation.
Ear puncture
Puncture of the ear drum may be due to an accident for example when something is stuck into the ear. Or it may be due to fluid pressure in the middle ear. Today the ear drum is occasionally punctured on purpose with surgery. A surgically placed tiny incision (a myringotomy) is made in the eardrum. Any fluid, usually thickened secretions, is removed and an ear tube may be inserted.
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