adj. (in anatomy) relating to or affecting one side of the body or one side of an organ or other part.
Disposable lenses are soft lenses designed to be thrown away after a short period of continuous use; their popularity rests on the fact that they need not be cleaned. The instructions on use should be followed carefully because the risk of complications, such as corneal infection, are higher than with other types of contact lenses.
Contraindications to the use of contact lenses include a history of ATOPY, ‘dry eyes’, previous GLAUCOMA surgery and a person’s inability to cope with the management of lenses. The best way to determine whether contact lenses are suitable, however, may be to try them out. Good hygiene is essential for wearers so as to minimise the risk of infection, which may lead to a corneal abscess – a serious complication. Corneal abrasions are fairly common and, if a contact-lens wearer develops a red eye, the lens should be removed and the eye tested with ?uorescein dye to identify any abrasions. Appropriate treatment should be given and the lens not worn again until the abrasion or infection has cleared up.... contact lenses
Before treatment, the patient will have been fasted for at least eight hours. After checking for any potential drug ALLERGY or interactions, the patient is given a general anaesthetic and muscle relaxants. Depending on the side of the patient’s dominance, either unilateral (on the side of the non-dominant hemisphere of the BRAIN) or bilateral (if dominance is uncertain,
e.g. in left-handed people) positioning of electrodes is used. Unilateral ECT has the advantage of being associated with less anterograde AMNESIA. When the current passes, the muscles will contract for approximately 10 seconds, with further tonic spasms lasting up to a minute. The patient should then be put in the COMA or recovery position and observed until fully conscious. Up to 12 treatments may be given over a month, improvement usually showing after the third session. Widely used at one time, the treatment is now given only rarely. It can be extremely frightening for patients and relatives and is not recommended for children.... electroconvulsive therapy (ect)
Treatment PENICILLIN in full dosage should be given orally for ten days. In those allergic to penicillin, ERYTHROMYCIN can be substituted. Recurrent attacks are common and may cause progressive lymphatic damage leading to chronic OEDEMA. Such recurrences can be prevented by long-term prophylactic oral penicillin.... erysipelas
Exophthalmos may also occur as a result of OEDEMA, injury, cavernous venous THROMBOSIS or a tumour at the back of the eye, pushing the eyeball forwards. In this situation it is always unilateral.... exophthalmos
It usually begins at puberty – although young children can be affected – and tends to stop in middle age: in women, for example, attacks often cease after MENOPAUSE. It frequently disappears during pregnancy. The disorder tends to run in families. In susceptible individuals, attacks may be provoked by a wide variety of causes including: anxiety, emotion, depression, shock, and excitement; physical and mental fatigue; prolonged focusing on computer, television or cinema screens; noise, especially loud and high-pitched sounds; certain foods – such as chocolate, cheese, citrus fruits, pastry; alcohol; prolonged lack of food; irregular meals; menstruation and the pre-menstrual period.
Anything that can provoke a headache in the ordinary individual can probably precipitate an attack in a migrainous subject. It seems as if there is an inherited predispostion that triggers a mechanism whereby in the migrainous subject, the headache and the associated sickness persist for hours, a whole day or even longer.
The precise cause is not known, but the generally accepted view is that in susceptible individuals, one or other of these causes produces spasm or constriction of the blood vessels of the brain. This in turn is followed by dilatation of these blood vessels which also become more permeable and so allow ?uid to pass out into the surrounding tissues. This combination of dilatation and outpouring of ?uid is held to be responsible for the headache.
Two types of migraine have been recognised: classical and common. The former is relatively rare and the headache is preceded by a slowly extending area of blindness in one or both eyes, usually accompanied by intermittent ‘lights’. The phenomenon lasts for up to 30 minutes and is followed by a bad, often unilateral headache with nausea, sometimes vomiting and sensitivity to light. Occasionally, passing neurological symptoms such as weakness in a limb may accompany the attack. The common variety has similar but less severe symptoms. It consists of an intense headache, usually situated over one or other eye. The headache is usually preceded by a feeling of sickness and disturbance of sight. In 15–20 per cent of cases this disturbance of sight takes the form of bright lights: the so-called AURA of migraine. The majority of attacks are accompanied by vomiting. The duration of the headache varies, but in the more severe cases the victim is usually con?ned to bed for 24 hours.
Treatment consists, in the ?rst place, of trying to avoid any precipitating factor. Patients must ?nd out which drug, or drugs, give them most relief, and they must always carry these about with them wherever they go. This is because it is a not uncommon experience to be aware of an attack coming on and to ?nd that there is a critical quarter of an hour or so during which the tablets are e?ective. If not taken within this period, they may be ine?ective and the unfortunate victim ?nds him or herself prostrate with headache and vomiting. In addition, sufferers should immediately lie down; at this stage a few hours’ rest may prevent the development of a full attack.
When an attack is fully developed, rest in bed in a quiet, darkened room is essential; any loud noise or bright light intensi?es the headache or sickness. The less food that is taken during an attack the better, provided that the individual drinks as much ?uid as he or she wants. Group therapy, in which groups of around ten migrainous subjects learn how to relax, is often of help in more severe cases, whilst in others the injection of a local anaesthetic into tender spots in the scalp reduces the number of attacks. Drug treatment can be e?ective and those a?icted by migraine may ?nd a particular drug or combination of drugs more suitable than others. ANALGESICS such as PARACETAMOL, aspirin and CODEINE phosphate sometimes help. A combination of buclizine hydrochloride and analgesics, taken when the visual aura occurs, prevents or diminishes the severity of an attack in some people. A commonly used remedy for the condition is ergotamine tartrate, which causes the dilated blood vessels to contract, but this must only be taken under medical supervision. In many cases METOCLOPRAMIDE (an antiemetic), followed ten minutes later by three tablets of either aspirin or paracetamol, is e?ective if taken early in an attack. In milder attacks, aspirin, with or without codeine and paracetamol, may be of value. SUMATRIPTAN (5-hydroxytryptamine [5HT1] AGONIST – also known as a SEROTONIN agonist) is of value for acute attacks. It is used orally or by subcutaneous injection, but should not be used for patients with ischaemic heart disease. Naratriptan is another 5HT1 agonist that is an e?ective treatment for acute attacks; others are almotriptan, rizariptan and zolmitriptan. Some patients ?nd beta blockers such as propranolol a valuable prophylactic.
People with migraine and their relatives can obtain help and guidance from the Migraine Action Association.... migraine
Naevus simplex Also known as ‘salmon patch’. About one-third of white children are born with macular pink areas of ERYTHEMA on the nape, brow or eyelids which usually disappear after a few months, but patches on the nape may persist.
Naevus ?ammeus Also known as ‘portwine stain’ and present at birth. It is unilateral, usually on the face, and may be extensive. It tends to darken with age and is permanent. Laser treatment is e?ective.
Strawberry naevus (cavernous haemangioma) is usually not present at birth but appears within a few weeks and grows rapidly, reaching a peak in size after 6–12 months, when the lobulated red nodule may resemble a ripe strawberry. Untreated, the naevus disappears spontaneously over several years. It may occur anywhere and may be very troublesome when occurring around an eye or on the ‘nappy’ area. If possible it should be left alone, but where it is causing problems other than simply cosmetic ones it is best treated by an expert. This may involve medical treatment with steroids or interferon or laser therapy.
Spider naevus is due to a dilated ARTERIOLE causing a minute red papule in the skin, the small branching vessels resembling spider legs. A few spider naevi are common in young people, but multiple naevi are common in pregnancy and may also be a warning sign of chronic liver disease.... naevus
Paralysis due to brain disease The most common form is unilateral palsy, or HEMIPLEGIA, generally arising from cerebral HAEMORRHAGE, THROMBOSIS or EMBOLISM affecting the opposite side of the BRAIN. If all four limbs and trunk are affected, the paralysis is called quadraplegia; if both legs and part of the trunk are affected, it is called paraplegia. Paralysis may also be divided into ?accid (?oppy limbs) or spastic (rigid).
In hemiplegia the cause may be an abscess, haemorrhage, thrombosis or TUMOUR in the brain. CEREBRAL PALSY or ENCEPHALITIS are other possible causes. Sometimes damage occurs in the parts of the nervous system responsible for the ?ne control of muscle movements: the cerebellum and basal ganglion are such areas, and lack of DOPAMINE in the latter causes PARKINSONISM.
Damage or injury Damage to or pressure on the SPINAL CORD may paralyse muscles supplied by nerves below the site of damage. A fractured spine or pressure from a tumour may have this e?ect. Disorders affecting the cord which can cause paralysis include osteoarthritis of the cervical vertebrae (see BONE, DISORDERS OF), MULTIPLE SCLEROSIS (MS), MYELITIS, POLIOMYELITIS and MENINGITIS. Vitamin B12 de?ciency (see APPENDIX 5: VITAMINS) may also cause deterioration in the spinal cord (see also SPINE AND SPINAL CORD, DISEASES AND INJURIES OF).
Neuropathies are a group of disorders, some inherited, that damage the peripheral nerves, thus affecting their ability to conduct electrical impulses. This, in turn, causes muscle weakness or paralysis. Among the causes of neuropathies are cancers, DIABETES MELLITUS, liver disease, and the toxic consequences of some drugs or metals – lead being one example.
Disorders of the muscles themselves – for example, muscular dystrophy (see MUSCLES, DISORDERS OF – Myopathy) – can disturb their normal working and so cause partial or complete paralysis of the part(s) affected.
Treatment The aim of treatment should be to remedy the underlying cause – for example, surgical removal of a displaced intervertebral
disc or treating diabetes mellitus. Sometimes the cause cannot be recti?ed but, whether treatable or not, physiotherapy is essential to prevent joints from seizing up and to try to maintain some tone in muscles that may be only partly affected. With temporary paralysis, such as can occur after a STROKE, physiotherapy can retrain the sufferers to use their muscles and joints to ensure mobility during and after recovery. Patients with permanent hemiplegia, paraplegia or quadraplegia need highly skilled nursing care, rehabilitative support and resources, and expert help to allow them, if possible, to live at home.... paralysis
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