Another name for the pinna, the external flap of the ear.
The term is also used to describe ear-like appendages of the atria (see atrium) of the heart.
The term is also used to describe ear-like appendages of the atria (see atrium) of the heart.
(1) the external ear, consisting of the auricle on the surface of the head, and the tube which leads inwards to the drum; (2) the middle ear, separated from the former by the tympanic membrane or drum, and from the internal ear by two other membranes, but communicating with the throat by the Eustachian tube; and (3) the internal ear, comprising the complicated labyrinth from which runs the vestibulocochlear nerve into the brain.
External ear The auricle or pinna consists of a framework of elastic cartilage covered by skin, the lobule at the lower end being a small mass of fat. From the bottom of the concha the external auditory (or acoustic) meatus runs inwards for 25 mm (1 inch), to end blindly at the drum. The outer half of the passage is surrounded by cartilage, lined by skin, on which are placed ?ne hairs pointing outwards, and glands secreting a small amount of wax. In the inner half, the skin is smooth and lies directly upon the temporal bone, in the substance of which the whole hearing apparatus is enclosed.
Middle ear The tympanic membrane, forming the drum, is stretched completely across the end of the passage. It is about 8 mm (one-third of an inch) across, very thin, and white or pale pink in colour, so that it is partly transparent and some of the contents of the middle ear shine through it. The cavity of the middle ear is about 8 mm (one-third of an inch) wide and 4 mm (one-sixth of an inch) in depth from the tympanic membrane to the inner wall of bone. Its important contents are three small bones – the malleus (hammer), incus (anvil) and stapes (stirrup) – collectively known as the auditory ossicles, with two minute muscles which regulate their movements, and the chorda tympani nerve which runs across the cavity. These three bones form a chain across the middle ear, connecting the drum with the internal ear. Their function is to convert the air-waves, which strike upon the drum, into mechanical movements which can affect the ?uid in the inner ear.
The middle ear has two connections which are of great importance as regards disease (see EAR, DISEASES OF). In front, it communicates by a passage 37 mm (1.5 inches) long – the Eustachian (or auditory) tube – with the upper part of the throat, behind the nose; behind and above, it opens into a cavity known as the mastoid antrum. The Eustachian tube admits air from the throat, and so keeps the pressure on both sides of the drum fairly equal.
Internal ear This consists of a complex system of hollows in the substance of the temporal bone enclosing a membranous duplicate. Between the membrane and the bone is a ?uid known as perilymph, while the membrane is distended by another collection of ?uid known as endolymph. This membranous labyrinth, as it is called, consists of two parts. The hinder part, comprising a sac (the utricle) and three short semicircular canals opening at each end into it, is the part concerned with the balancing sense; the forward part consists of another small bag (the saccule), and of a still more important part, the cochlear duct, and is the part concerned with hearing. In the cochlear duct is placed the spiral organ of Corti, on which sound-waves are ?nally received and by which the sounds are communicated to the cochlear nerve, a branch of the vestibulocochlear nerve, which ends in ?laments to this organ of Corti. The essential parts in the organ of Corti are a double row of rods and several rows of cells furnished with ?ne hairs of varying length which respond to di?ering sound frequencies.
The act of hearing When sound-waves in the air reach the ear, the drum is alternately pressed in and pulled out, in consequence of which a to-and-fro movement is communicated to the chain of ossicles. The foot of the stapes communicates these movements to the perilymph. Finally these motions reach the delicate ?laments placed in the organ of Corti, and so affect the auditory nerve, which conveys impressions to the centre in the brain.... ear
Examination of the ear includes inspection of the external ear. An auriscope is used to examine the external ear canal and the ear drum. If a more detailed inspection is required, a microscope may be used to improve illumination and magni?cation.
Tuning-fork or Rinne tests are performed to identify the presence of DEAFNESS. The examiner tests whether the vibrating fork is audible at the meatus, and then the foot of the fork is placed on the mastoid bone of the ear to discover at which of the two sites the patient can hear the vibrations for the longest time. This can help to di?erentiate between conductive and nerve deafness.
Hearing tests are carried out to determine the level of hearing. An audiometer is used to deliver a series of short tones of varying frequency to the ear, either through a pair of headphones or via a sound transducer applied directly to the skull. The intensity of the sound is gradually reduced until it is no longer heard and this represents the threshold of hearing, at that frequency, through air and bone respectively. It may be necessary to play a masking noise into the opposite ear to prevent that ear from hearing the tones, enabling each ear to be tested independently.
General symptoms The following are some of the chief symptoms of ear disease: DEAFNESS (see DEAFNESS). EARACHE is most commonly due to acute in?ammation of the middle ear. Perceived pain in this region may be referred from other areas, such as the earache commonly experienced after tonsillectomy (removal of the TONSILS) or that caused by carious teeth (see TEETH, DISORDERS OF). The treatment will depend on the underlying cause. TINNITUS or ringing in the ear often accompanies deafness, but is sometimes the only symptom of ear disease. Even normal people sometimes experience tinnitus, particularly if put in soundproofed surroundings. It may be described as hissing, buzzing, the sound of the sea, or of bells. The intensity of the tinnitis usually ?uctuates, sometimes disappearing altogether. It may occur in almost any form of ear disease, but is particularly troublesome in nerve deafness due to ageing and in noise-induced deafness. The symptom seems to originate in the brain’s subcortical regions, high in the central nervous system. It may be a symptom of general diseases such as ANAEMIA, high blood pressure and arterial disease, in which cases it is often synchronous with the pulse, and may also be caused by drugs such as QUININE, salicylates (SALICYLIC ACID and its salts, for example, ASPIRIN) and certain ANTIBIOTICS. Treatment of any underlying ear disorder or systemic disease, including DEPRESSION, may reduce or even cure the tinnitis, but unfortunately in many cases the noises persist. Management involves psychological techniques and initially an explanation of the mechanism and reassurance that tinnitus does not signify brain disease, or an impending STROKE, may help the person. Tinnitus maskers – which look like hearing aids – have long been used with a suitably pitched sound helping to ‘mask’ the condition.
Diseases of the external ear
WAX (cerumen) is produced by specialised glands in the outer part of the ear canal only. Impacted wax within the ear canal can cause deafness, tinnitis and sometimes disturbance of balance. Wax can sometimes be softened with olive oil, 5-per-cent bicarbonate of soda or commercially prepared drops, and it will gradually liquefy and ‘remove itself’. If this is ineffective, syringing by a doctor or nurse will usually remove the wax but sometimes it is necessary for a specialist (otologist) to remove it manually with instruments. Syringing should not be done if perforation of the tympanic membrane (eardrum) is suspected. FOREIGN BODIES such as peas, beads or buttons may be found in the external ear canal, especially in children who have usually introduced them themselves. Live insects may also be trapped in the external canal causing intense irritation and noise, and in such cases spirit drops are ?rst instilled into the ear to kill the insect. Except in foreign bodies of vegetable origin, where swelling and pain may occur, syringing may be used to remove some foreign bodies, but often removal by a specialist using suitable instrumentation and an operating microscope is required. In children, a general anaesthetic may be needed. ACUTE OTITIS EXTERNA may be a di?use in?ammation or a boil (furuncle) occurring in the outer ear canal. The pinna is usually tender on movement (unlike acute otitis media – see below) and a discharge may be present. Initially treatment should be local, using magnesium sulphate paste or glycerine and 10-per-cent ichthaminol. Topical antibiotic drops can be used and sometimes antibiotics by mouth are necessary, especially if infection is acute. Clotrimazole drops are a useful antifungal treatment. Analgesics and locally applied warmth should relieve the pain.
CHRONIC OTITIS EXTERNA producing pain and discharge, can be caused by eczema, seborrhoeic DERMATITIS or PSORIASIS. Hair lotions and cosmetic preparations may trigger local allergic reactions in the external ear, and the chronic disorder may be the result of swimming or use of dirty towels. Careful cleaning of the ear by an ENT (Ear, Nose & Throat) surgeon and topical antibiotic or antifungal agents – along with removal of any precipitating cause – are the usual treatments. TUMOURS of the ear can arise in the skin of the auricle, often as a result of exposure to sunlight, and can be benign or malignant. Within the ear canal itself, the commonest tumours are benign outgrowths from the surrounding bone, said to occur in swimmers as a result of repeated exposure to cold water. Polyps may result from chronic infection of the ear canal and drum, particularly in the presence of a perforation. These polyps are soft and may be large enough to ?ll the ear canal, but may shrink considerably after treatment of the associated infection.
Diseases of the middle ear
OTITIS MEDIA or infection of the middle ear, usually occurs as a result of infection spreading up the Eustachian tubes from the nose, throat or sinuses. It may follow a cold, tonsillitis or sinusitis, and may also be caused by swimming and diving where water and infected secretions are forced up the Eustachian tube into the middle ear. Primarily it is a disease of children, with as many as 1.5 million cases occurring in Britain every year. Pain may be intense and throbbing or sharp in character. The condition is accompanied by deafness, fever and often TINNITUS.
In infants, crying may be the only sign that something is wrong – though this is usually accompanied by some localising manifestation such as rubbing or pulling at the ear. Examination of the ear usually reveals redness, and sometimes bulging, of the ear drum. In the early stages there is no discharge, but in the later stages there may be a discharge from perforation of the ear drum as a result of the pressure created in the middle ear by the accumulated pus. This is usually accompanied by an immediate reduction in pain.
Treatment consists of the immediate administration of an antibiotic, usually one of the penicillins (e.g. amoxicillin). In the majority of cases no further treatment is required, but if this does not quickly bring relief then it may be necessary to perform a myringotomy, or incision of the ear drum, to drain pus from the middle ear. When otitis media is treated immediately with su?cient dosage of the appropriate antibiotic, the chances of any permanent damage to the ear or to hearing are reduced to a negligible degree, as is the risk of any complications such as mastoiditis (discussed later in this section). CHRONIC OTITIS MEDIA WITH EFFUSION or glue ear, is the most common in?ammatory condition of the middle ear in children, to the extent that one in four children in the UK entering school has had an episode of ‘glue ear’. It is characterised by a persistent sticky ?uid in the middle ear (hence the name); this causes a conductive-type deafness. It may be associated with enlarged adenoids (see NOSE, DISORDERS OF) which impair the function of the Eustachian tube. If the hearing impairment is persistent and causes problems, drainage of the ?uid, along with antibiotic treatment, may be needed – possibly in conjunction with removal of the adenoids. The insertion of grommets (ventilation tubes) was for a time standard treatment, but while hearing is often restored, there may be no long-term gain and even a risk of damage to the tympanic membrane, so the operation is less popular than it was a decade or so ago. MASTOIDITIS is a serious complication of in?ammation of the middle ear, the incidence of which has been dramatically reduced by the introduction of antibiotics. In?ammation in this cavity usually arises by direct spread of acute or chronic in?ammation from the middle ear. The signs of this condition include swelling and tenderness of the skin behind the ear, redness and swelling inside the ear, pain in the side of the head, high fever, and a discharge from the ear. The management of this condition in the ?rst instance is with antibiotics, usually given intravenously; however, if the condition fails to improve, surgical treatment is necessary. This involves draining any pus from the middle ear and mastoid, and removing diseased lining and bone from the mastoid.
Diseases of the inner ear
MENIÈRE’S DISEASE is a common idiopathic disorder of ENDOLYMPH control in the semicircular canals (see EAR), characterised by the triad of episodic VERTIGO with deafness and tinnitus. The cause is unknown and usually one ear only is affected at ?rst, but eventually the opposite ear is affected in approximately 50 per cent of cases. The onset of dizziness is often sudden and lasts for up to 24 hours. The hearing loss is temporary in the early stages, but with each attack there may be a progressive nerve deafness. Nausea and vomiting often occur. Treatment during the attacks includes rest and drugs to control sickness. Vasodilator drugs such as betahistine hydrochloride may be helpful. Surgical treatment is sometimes required if crippling attacks of dizziness persist despite these measures. OTOSCLEROSIS A disorder of the middle ear that results in progressive deafness. Often running in families, otosclerosis affects about one person in 200; it customarily occurs early in adult life. An overgrowth of bone ?xes the stapes (the innermost bone of the middle ear) and stops sound vibrations from being transmitted to the inner ear. The result is conductive deafness. The disorder usually affects both ears. Those affected tend to talk quietly and deafness increases over a 10–15 year period. Tinnitus often occurs, and occasionally vertigo.
Abnormal hearing tests point to the diagnosis; the deafness may be partially overcome with a hearing aid but surgery is eventually needed. This involves replacing the stapes bone with a synthetic substitute (stapedectomy). (See also OTIC BAROTRAUMA.)... ear, diseases of
Shape and size In adults the heart is about the size and shape of a clenched ?st. One end of the heart is pointed (apex); the other is broad (base) and is deeply cleft at the division between the two atria. One groove running down the front and up the back shows the division between the two ventricles; a circular, deeper groove marks o? the atria above from the ventricles below. The capacity of each cavity is somewhere between 90 and 180 millilitres.
Structure The heart lies within a strong ?brous bag, known as the pericardium. Since the inner surface of this bag and the outer surface of the heart are both covered with a smooth, glistening membrane faced with ?at cells and lubricated by a little serous ?uid (around 20 ml), the movements of the heart are accomplished almost without friction. The main thickness of the heart wall consists of bundles of muscle ?bres, some of which run in circles right around the heart, and others in loops, ?rst round one cavity, then round the corresponding cavity of the other side. Within all the cavities is a smooth lining membrane, continuous with that lining the vessels which open into the heart. The investing smooth membrane is known as epicardium; the muscular substance as myocardium; and the smooth lining membrane as endocardium.
Important nerves regulate the heart’s action, especially via the vagus nerve and with the sympathetic system (see NERVOUS SYSTEM). In the near part of the atria lies a collection of nerve cells and connecting ?bres, known as the sinuatrial node or pacemaker, which forms the starting-point for the impulses that initiate the beats of the heart. In the groove between the ventricles and the atria lies another collection of similar nerve tissue, known as the atrioventricular node. Running down from there into the septum between the two ventricles is a band of special muscle ?bres, known as the atrioventricular bundle, or the bundle of His. This splits up into a right and a left branch for the two ventricles, and the ?bres of these distribute themselves throughout the muscular wall of the ventricles and control their contraction.
Openings There is no direct communication between the cavities on the right side and those on the left; but the right atrium opens into the right ventricle by a large circular opening, and similarly the left atrium into the left ventricle. Into the right atrium open two large veins, the superior and inferior venae cavae, with some smaller veins from the wall of the heart itself, and into the left atrium open two pulmonary veins from each lung. One opening leads out of each ventricle – to the aorta in the case of the left ventricle, to the pulmonary artery from the right.
Before birth, the FETUS’s heart has an opening (foramen ovale) from the right into the left atrium through which the blood passes; but when the child ?rst draws air into his or her lungs this opening closes and is represented in the adult only by a depression (fossa ovalis).
Valves The heart contains four valves. The mitral valve consists of two triangular cusps; the tricuspid valve of three smaller cusps. The aortic and pulmonary valves each consist of three semilunar-shaped segments. Two valves are placed at the openings leading from atrium into ventricle, the tricuspid valve on the right side, the mitral valve on the left, so as completely to prevent blood from running back into the atrium when the ventricle contracts. Two more, the pulmonary valve and the aortic valve, are at the entrance to these arteries, and prevent regurgitation into the ventricles of blood which has been driven from them into the arteries. The noises made by these valves in closing constitute the greater part of what are known as the heart sounds, and can be heard by anyone who applies his or her ear to the front of a person’s chest. Murmurs heard accompanying these sounds indicate defects in the valves, and may be a sign of heart disease (although many murmurs, especially in children, are ‘innocent’).
Action At each heartbeat the two atria contract and expel their contents into the ventricles, which at the same time they stimulate to contract together, so that the blood is driven into the arteries, to be returned again to the atria after having completed a circuit in about 15 seconds through the body or lungs as the case may be. The heart beats from 60 to 90 times a minute, the rate in any given healthy person being about four times that of the respirations. The heart is to some extent regulated by a nerve centre in the MEDULLA, closely connected with those centres which govern the lungs and stomach, and nerve ?bres pass to it in the vagus nerve. The heart rate and force can be diminished by some of these ?bres, by others increased, according to the needs of the various organs of the body. If this nerve centre is injured or poisoned – for example, by lack of oxygen – the heart stops beating in human beings; although in some of the lower animals (e.g. frogs, ?shes and reptiles) the heart may under favourable conditions go on beating for hours even after its entire removal from the body.... heart
Habitat: The temperate Himalayas from 1,500 to 2,400 m, in the Khasi hills and in Kashmir, Punjab, Delhi, Uttar Pradesh, Bihar and Orissa.
Ayurvedic: Pitarangaa, Piyaaraan- gaa. Pitamuulikaa (substitute).Unani: Mamiri. (Mamiraa is equated with Coptis teeta Wall.)Action: Plant—used against gout and rheumatism. Root—febrifuge, antiperiodic; a bitter tonic during convalescence.
The root contains alkaloids berberine and magnoflorine. (Berberine causes a stimulant action on the movements of the gastrointestinal tract, a depression of both the auricles and ventricles and distinct dilatation of the heart. Magnoflorine induces hypoten- tion.) Berberine content is reduced to one-fourth and magnoflorine to traces after 6 months. The root also contains palmitine and jatrorrhizine.Thalictrum sp. (about 17 species are found in India)—alkaloidal structure exhibits antitumoral activity.Over 60 isoquinoline and diter- penoid alkaloids have been isolated. (See The Wealth of India, Vol. X.)Following are the important Thalic- trum sp. occurring in India:T. alpinum Linn. (the alpine Himalayas and western Tibet at altitudes between 3,000 and 5,100 m); T. ele- gans Wall. ex Royle (the sub-alpine Himalayas from Kashmir to Sikkim at altitudes from 3,000 to 3,900 m); T. foetidum Linn. (North-West Himalayas); T. javanicum Blume (the temperate Himalayas from Kashmir to Sikkim, Khasi hills, Kodaikanal and Nilgiri hills); T. minus Linn. (the temperate Himalayas); T. reniforme Wall. (the temperate Himalayas from Kulu to Sikkim between 2,400 and 3,000 m).... thalictrum foliolosumMitral disease leads to heart failure either by a narrowing of the orifice (stenosis) or a regurgitation blocks the passage of blood from the left atrium (auricle) to the left ventricle. The left atrium enlarges (hypertrophies) in an effort to counter the impediment. Real compensation – increased thrust of the blood – is provided by the right ventricle. In order to overcome a mitral impediment the right ventricle has to enlarge.
Sooner or later the right ventricle cannot enlarge any further and general heart failure sets in. Though caused primarily by a lesion of the mitral valve, it may be secondary to left ventricular failure (LVF), thyroid disorder (thyrotoxicosis), pericarditis, congenital heart disease, or any disease which weakens ventricular muscle.
Venous congestion and back pressure of RVF leads to congestion and accumulation of fluid in the lungs, cough and spitting of blood, painful swelling of the liver, nausea, loss of appetite and severe wasting.
Where the right ventricle fails to move the blood forward as it arrives from the systemic circulation, generalised dropsy sets in. Congestion of the kidneys leads to reduced urinary excretion and presence of albumin in the urine.
The picture is well known to the cardiac practitioner: blueness of the skin, congestion of the brain circulation with sleeplessness and delirium. Soon the tension of water-logged tissues results in pain and extreme anxiety. Feet are swollen and ankles pit on pressure; chest cavities fill with fluid and the abdomen swells (ascites).
Alternatives. Cardio-tonics would be given to strengthen the ventricle and diuretics to correct fluid retention: Lily of the Valley, Hawthorn, Motherwort, Broom. BHP (1983).
Due to rheumatic fever: Hawthorn.
High Blood Pressure: Mistletoe.
Effort Syndrome: Motherwort.
Tinctures. Combine, Lily of the Valley 2; Hawthorn 2; Motherwort 3. Dose: 1 teaspoon thrice daily after meals.
Diet. Low salt, low fat, high fibre. Restricted fluids, vegetarian protein foods, yoghurt. See also: DIET – HEART AND CIRCULATION.
Supplements. Potassium (bananas), Vitamin B6.
General. Stop smoking. Correction of overweight. Complete bed-rest with legs raised above level of the abdomen and patient propped-up to relieve difficult breathing. ... heart – right ventricular failure (rvf)
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