A hypothetical condition thought to account for behavioural and other problems in children for which no physical cause is found. It may be a cause of some learning difficulties, difficulty in concentrating, impulsiveness, and hyperactivity.
The control centre of the whole nervous system is the brain, which is located in the skull or cranium. As well as controlling the nervous system it is the organ of thought, speech and emotion. The central nervous system controls the body’s essential functions such as breathing, body temperature (see HOMEOSTASIS) and the heartbeat. The body’s various sensations, including sight, hearing, touch, pain, positioning and taste, are communicated to the CNS by nerves distributed throughout the relevant tissues. The information is then sorted and interpreted by specialised areas in the brain. In response these initiate and coordinate the motor output, triggering such ‘voluntary’ activities as movement, speech, eating and swallowing. Other activities – for example, breathing, digestion, heart contractions, maintenance of BLOOD PRESSURE, and ?ltration of waste products from blood passing through the kidneys – are subject to involuntary control via the autonomic system. There is, however, some overlap between voluntary and involuntary controls.... brain
Sexual dysfunction may be due to physical or psychiatric disease, or it may be the result of the administration of drugs. The main group of drugs likely to cause sexual problems are the ANTICONVULSANTS, the ANTIHYPERTENSIVE DRUGS, and drugs such as metoclopramide that induce HYPERPROLACTINAEMIA. The benzodiazepine TRANQUILLISERS can reduce libido and cause failure of erection. Tricyclic ANTIDEPRESSANT DRUGS may cause failure of erection and clomipramine may delay or abolish ejaculation by blockade of alpha-adrenergic receptors. The MONOAMINE OXIDASE INHIBITORS (MAOIS) often inhibit ejaculation. The PHENOTHIAZINES reduce sexual desire and arousal and may cause di?culty in maintaining an erection. The antihypertensive drug, methyldopa, causes impotence in over 20 per cent of patients on large doses. The beta-adrenoceptorblockers and the DIURETICS can also cause impotence. The main psychiatric causes of sexual dysfunction include stress, depression and guilt.... sexual dysfunction
Symptoms include muscle weakness, loss of vision, or other sensory disturbances, speech difficulties, and epileptic seizures. Increased pressure within the skull can cause headache, visual disturbances, vomiting, and impaired mental functioning. Hydrocephalus may occur.
When possible, primary tumours are removed by surgery after opening the skull (see craniotomy).
In cases where a tumour cannot be completely removed, as much as possible of it will be cut away to relieve pressure.
For primary and secondary tumours, radiotherapy or anticancer drugs may also be given.
Corticosteroid drugs are often prescribed temporarily to reduce the size of a tumour and associated brain swelling.... brain tumour
Absent CORNEAL REFLEX
Absent VESTIBULO-OCULAR REFLEX
No cranial motor response to somatic (physical) stimulation
Absent gag and cough re?exes
No respiratory e?ort in response to APNOEA despite adequate concentrations of CARBON DIOXIDE in the arterial blood.... b nosed. the test for brain-stem death are:
Severe head injuries cause unconsciousness for hours or many days, followed by loss of memory before and after that period of unconsciousness. The skull may be fractured; there may be ?ts in the ?rst week; and there may develop a blood clot in the brain (intracerebral haematoma) or within the membranes covering the brain (extradural and subdural haematomata). These clots compress the brain, and the pressure inside the skull – intracranial pressure – rises with urgent, life-threatening consequences. They are identi?ed by neurologists and neurosurgeons, con?rmed by brain scans (see COMPUTED TOMOGRAPHY; MRI), and require urgent surgical removal. Recovery may be complete, or in very severe cases can be marred by physical disabilities, EPILEPSY, and by changes in intelligence, rational judgement and behaviour. Symptoms generally improve in the ?rst two years.
A minority of those with minor head injuries have complaints and disabilities which seem disproportionate to the injury sustained. Referred to as the post-traumatic syndrome, this is not a diagnostic entity. The complaints are headaches, forgetfulness, irritability, slowness, poor concentration, fatigue, dizziness (usually not vertigo), intolerance of alcohol, light and noise, loss of interests and initiative, DEPRESSION, anxiety, and impaired LIBIDO. Reassurance and return to light work help these symptoms to disappear, in most cases within three months. Psychological illness and unresolved compensation-claims feature in many with implacable complaints.
People who have had brain injuries, and their relatives, can obtain help and advice from Headwat and from www.neuro.pmr.vcu.edu and www.biausa.org... brain injuries
II. Optic, to the eye (sight).
III. Oculomotor
Trochlear, to eye-muscles.
Abducent
VI. Trigeminal, to skin of face.
VII. Facial, to muscles of face.
VIII. Vestibulocochlear, to ear (hearing and balancing).
IX. Glossopharyngeal, to tongue (taste).
X. Vagus, to heart, larynx, lungs, and stomach.
XI. Spinal accessory, to muscles in neck.
XII. Hypoglossal, to muscles of tongue.... nerves twelve nerves come off the brain:
All reversible pharmacological, metabolic, endocrine and physiological causes must be excluded, and there should be no doubt that irreversible brain damage has occurred. Two senior doctors carry out diagnostic tests to con?rm that brain-stem re?exes are absent. These tests must be repeated after a suitable interval before death can be declared. Imaging techniques are not required for death to be diag-... brain-stem death
Abscess, Alzheimer’s Disease, anoxia (oxygen starvation), coma, concussion, haemorrhage, Down’s syndrome, epilepsy, tumour, hydrocephalus (water on the brain), meningitis, multiple sclerosis, stroke (rupture of blood vessel), spina bifida, syphilis (general paralysis of the insane), sleepy sickness.
Poor circulation through the brain due to hardening of the arteries: Ginkgo, Ginseng. Ginseng stimulates the hypothalmic/pituitary axis of the brain and favourably influences its relationship with the adrenal glands.
Congestion of the brain – Cowslip (Boerwicke). Irritability of brain and spine – Hops. Oats. Inflammation of the brain (encephalitis) as in viral infection, poliomyelitis, rabies, sleepy sickness, etc: Echinacea, Passion flower, Skullcap and Lobelia. Gelsemium acts as a powerful relaxant in the hands of a practitioner: Tincture BPC (1973): dose 0.3ml.
Brain storm from hysteria, locomotor ataxia, etc – Liquid Extract Lobelia: 5ml teaspoon in water when necessary (Dr Jentzsch, 1915, Ellingwood) Supplement with Zinc, Vitamins C and E.
Blood clot, thrombosis: Yarrow. Neurasthenia: Oats, Basil, Hops.
Brain fag and jet-lag: Chamomile, Skullcap, Oats, Ginseng, Ginkgo.
Tumour may be present years before manifesting: Goldenseal.
Mental state: depression, anxiety, schizophrenia.
Tea. Formula. Skullcap, Gotu Kola and German Chamomile; equal parts. 1 heaped teaspoon to each cup water gently simmered 10 minutes. Strain. 1 cup thrice daily.
Unspecified tensive state. Formula. Tinctures. Hops 1; Passion flower 2; Valerian 2. Dose: 2 teaspoons thrice daily until diagnosis is concluded.
Unspecified torpor. Formula. Tinctures. Ginseng 1; Kola 1; Capsicum quarter. 2 teaspoons in water thrice daily until diagnosis is concluded.
Brain weakness in the elderly: Ginkgo. See: ALZHEIMER’S DISEASE.
Fluid on the brain: see HYDROCEPHALUS.
Abscess of the brain: see ABSCESS.
Brain restoratives. Black Haw, True Unicorn root, Galangal, Oats, Oatstraw, False Unicorn root, Kola, Hops. Vitamin B6. Magnesium.
Cerebral thrombosis. See entry.
Note: Cold water may help victims to survive: rapid loss of body heat protects the brain. (Child Health Department, University of Wales)
Treatment by or in liaison with general medical practitioner or hospital specialist. ... brain disorders
Tumours All masses cause varying combinations of headache and vomiting – symptoms of raised pressure within the inexpansible bony box formed by the skull; general or localised epileptic ?ts; weakness of limbs or disordered speech; and varied mental changes. Tumours may be primary, arising in the brain, or secondary deposits from tumours arising in the lung, breast or other organs. Some brain tumours are benign and curable by surgery: examples include meningiomas and pituitary tumours. The symptoms depend on the size and situation of the mass. Abscesses or blood clots (see HAEMATOMA) on the surface or within the brain may resemble tumours; some are removable. Gliomas ( see GLIOMA) are primary malignant tumours arising in the glial tissue (see GLIA) which despite surgery, chemotherapy and radiotherapy usually have a bad prognosis, though some astrocytomas and oligodendronogliomas are of low-grade malignancy. A promising line of research in the US (in the animal-testing stage in 2000) suggests that the ability of stem cells from normal brain tissue to ‘home in’ on gliomal cells can be turned to advantage. The stem cells were chemically manipulated to carry a poisonous compound (5-?uorouracil) to the gliomal cells and kill them, without damaging normal cells. Around 80 per cent of the cancerous cells in the experiments were destroyed in this way.
Clinical examination and brain scanning (CT, or COMPUTED TOMOGRAPHY; magnetic resonance imaging (MRI) and functional MRI) are safe, accurate methods of demonstrating the tumour, its size, position and treatability.
Strokes When a blood vessel, usually an artery, is blocked by a clot, thrombus or embolism, the local area of the brain fed by that artery is damaged (see STROKE). The resulting infarct (softening) causes a stroke. The cells die and a patch of brain tissue shrinks. The obstruction in the blood vessel may be in a small artery in the brain, or in a larger artery in the neck. Aspirin and other anti-clotting drugs reduce recurrent attacks, and a small number of people bene?t if a narrowed neck artery is cleaned out by an operation – endarterectomy. Similar symptoms develop abruptly if a blood vessel bursts, causing a cerebral haemorrhage. The symptoms of a stroke are sudden weakness or paralysis of the arm and leg of the opposite side to the damaged area of brain (HEMIPARESIS), and sometimes loss of half of the ?eld of vision to one side (HEMIANOPIA). The speech area is in the left side of the brain controlling language in right-handed people. In 60 per cent of lefthanders the speech area is on the left side, and in 40 per cent on the right side. If the speech area is damaged, diffculties both in understanding words, and in saying them, develops (see DYSPHASIA).
Degenerations (atrophy) For reasons often unknown, various groups of nerve cells degenerate prematurely. The illness resulting is determined by which groups of nerve cells are affected. If those in the deep basal ganglia are affected, a movement disorder occurs, such as Parkinson’s disease, hereditary Huntington’s chorea, or, in children with birth defects of the brain, athetosis and dystonias. Modern drugs, such as DOPAMINE drugs in PARKINSONISM, and other treatments can improve the symptoms and reduce the disabilities of some of these diseases.
Drugs and injury Alcohol in excess, the abuse of many sedative drugs and arti?cial brain stimulants – such as cocaine, LSD and heroin (see DEPENDENCE) – can damage the brain; the effects can be reversible in early cases. Severe head injury can cause localised or di?use brain damage (see HEAD INJURY).
Cerebral palsy Damage to the brain in children can occur in the uterus during pregnancy, or can result from rare hereditary and genetic diseases, or can occur during labour and delivery. Severe neurological illness in the early months of life can also cause this condition in which sti? spastic limbs, movement disorders and speech defects are common. Some of these children are learning-disabled.
Dementias In older people a di?use loss of cells, mainly at the front of the brain, causes ALZHEIMER’S DISEASE – the main feature being loss of memory, attention and reasoned judgement (dementia). This affects about 5 per cent of the over-80s, but is not simply due to ageing processes. Most patients require routine tests and brain scanning to indicate other, treatable causes of dementia.
Response to current treatments is poor, but promising lines of treatment are under development. Like Parkinsonism, Alzheimer’s disease progresses slowly over many years. It is uncommon for these diseases to run in families. Multiple strokes can cause dementia, as can some organic disorders such as cirrhosis of the liver.
Infections in the brain are uncommon. Viruses such as measles, mumps, herpes, human immunode?ciency virus and enteroviruses may cause ENCEPHALITIS – a di?use in?ammation (see also AIDS/HIV).
Bacteria or viruses may infect the membrane covering the brain, causing MENINGITIS. Viral meningitis is normally a mild, self-limiting infection lasting only a few days; however, bacterial meningitis – caused by meningococcal groups B and C, pneumococcus, and (now rarely) haemophilus – is a life-threatening condition. Antibiotics have allowed a cure or good control of symptoms in most cases of meningitis, but early diagnosis is essential. Severe headaches, fever, vomiting and increasing sleepiness are the principal symptoms which demand urgent advice from the doctor, and usually admission to hospital. Group B meningococcus is the commonest of the bacterial infections, but Group C causes more deaths. A vaccine against the latter has been developed and has reduced the incidence of cases by 75 per cent.
If infection spreads from an unusually serious sinusitis or from a chronically infected middle ear, or from a penetrating injury of the skull, an abscess may slowly develop. Brain abscesses cause insidious drowsiness, headaches, and at a late stage, weakness of the limbs or loss of speech; a high temperature is seldom present. Early diagnosis, con?rmed by brain scanning, is followed by antibiotics and surgery in hospital, but the outcome is good in only half of affected patients.
Cerebral oedema Swelling of the brain can occur after injury, due to engorgement of blood vessels or an increase in the volume of the extravascular brain tissue due to abnormal uptake of water by the damaged grey (neurons) matter and white (nerve ?bres) matter. This latter phenomenon is called cerebral oedema and can seriously affect the functioning of the brain. It is a particularly dangerous complication following injury because sometimes an unconscious person whose brain is damaged may seem to be recovering after a few hours, only to have a major relapse. This may be the result of a slow haemorrhage from damaged blood vessels raising intracranial pressure, or because of oedema of the brain tissue in the area surrounding the injury. Such a development is potentially lethal and requires urgent specialist treatment to alleviate the rising intracranial pressure: osmotic agents (see OSMOSIS) such as mannitol or frusemide are given intravenously to remove the excess water from the brain and to lower intracranial pressure, buying time for de?nitive investigation of the cranial damage.... brain, diseases of
Brain abscesses may occur after a head injury, but most cases result from the spread of infection from elsewhere in the body, such as the middle ear or sinuses.
Another cause is an infection following a penetrating brain injury.
Multiple brain abscesses may occur as a result of blood-borne infection, most commonly in patients with a heart-valve infection (see endocarditis).
Symptoms include headache, drowsiness, vomiting, visual disturbances, fever, seizures, and symptoms, such as speech disturbances, that are due to local pressure.
Treatment is with antibiotic drugs and surgery.
A craniotomy may be needed to open and drain the abscess.
Untreated, brain abscesses can cause permanent damage or can be fatal.
Despite treatment, scarring can cause epilepsy in some cases.... brain abscess
Localized brain damage may occur as a result of a head injury, stroke, brain tumour, or brain abscess. At birth, a raised blood level of bilirubin (in haemolytic disease of the newborn) causes local damage to the basal ganglia deep within the brain. This leads to a condition called kernicterus. Brain damage that occurs before, during, or after birth may result in cerebral palsy.
Damage to the brain may result in disabilities such as learning difficulties or disturbances of movement or speech.
Nerve cells and tracts in the brain and spinal cord cannot repair themselves once they have been damaged, but some return of function may be possible.... brain damage
Reduced oxygen supply may occur at birth, causing cerebral palsy. Later in life, cerebral hypoxia can result from choking or from arrest of breathing and heartbeat. From middle age onwards, cerebrovascular disease is the most important cause of brain disorder. If an artery within the brain becomes blocked or ruptures, leading to haemorrhage, the result is a stroke. The brain may also be damaged by a blow to the head see head injury).
Infection within the brain (encephalitis) may be due to viral infection. Infection of the membranes surrounding the brain (meningitis) is generally due to bacterial infection. Creutzfeldt–Jakob disease is a rare, fatal brain disease associated with an infective agent called a prion which, in some cases, has been linked with (bovine spongiform encephalopathy), a disease in cattle.
Multiple sclerosis is a progressive disease of the brain and spinal cord. Degenerative brain diseases include Alzheimer’s disease and Parkinson’s disease. Emotional or behavioural disorders are generally described as psychiatric illnesses; but the distinction between neurological and psychiatric disorders is now much less clear.... brain, disorders of
scanning gives images of the brain substance; it gives clear pictures of the ventricles (fluid-filled cavities) and can reveal tumours, blood clots, strokes, aneurysms, and abscesses. is especially helpful in showing tumours of the posterior fossa (back of the skull). and scanning are specialized forms of radionuclide scanning that use small amounts of radioactive material to give information about brain function as well as structure. They enable
blood flow and metabolic activity in the brain to be measured.
Ultrasound scanning is used only in premature or very young babies since ultrasound waves cannot penetrate the bones of a mature skull.... brain imaging
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