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Cephalic disorders are not necessarily caused by a single factor, but may be influenced by hereditary or genetic conditions, nutritional deficiencies, or by environmental exposures during pregnancy, such as medication taken by the mother, maternal infection, or exposure to radiation (such disorders are more common in areas of the former Soviet Union affected by nuclear waste disposal problems, such as the area around the Mayak plant in Chelyabinsk, Russia.) Some cephalic disorders occur when the cranial sutures (the fibrous joints that connect the bones of the skull) join prematurely. Most cephalic disorders are caused by a disturbance that occurs very early in the development of the fetalA fetus (alternatively foetus is an embryo in later stages of development, from the third month of pregnancy until birth in humans. Fetus literally means 'young one'. Fetal growth There is much natural variation in the growth of the fetus. Approximately 4 nervous system.
The human nervous system develops from a small, specialized plate of cellsstained for keratin The cell is the structural and functional unit of all living organisms. Some organisms, such as bacteria, are unicellular, consisting of a single cell. Other organisms, such as humans, are multicellular, (humans have an estimated 100,0 on the surface of the embryotadpole) of the wrinkled frog Rana rugosa . An embryo is an animal or a plant in its earliest stage of development. Plants In botany, a plant embryo is part of a seed, consisting of precursor tissues for the leaves, stem (see hypocotyl , and root (see rad. Early in development, this plate of cells forms the neural tube, a narrow sheath that closes between the third and fourth weeks of pregnancy to form the brain and spinal cordThe spinal cord is a part of the vertebrate nervous system that is enclosed in and protected by the vertebral column (it passes through the spinal canal). It consists of nerve cells. The cord conveys the 31 spinal nerve pairs of the peripheral nervous sys of the embryo. Four main processes are responsible for the development of the nervous system: cell proliferation, the process in which nerveA nerve is an enclosed, cable-like bundle of nerve fibers or axons, which includes the glia that ensheath the axons in myelin. Neurons are sometimes called nerve cells though this term is technically imprecise since many neurons do not form nerves. Nerves cells divide to form new generations of cells; cell migration, the process in which nerve cells move from their place of origin to the place where they will remain for life; cell differentiation, the process during which cells acquire individual characteristics; and cell death, a natural process in which cells die.
Damage to the developing nervous system is a major cause of chronic, disabling disorders and, sometimes, death in infants, children, and even adults. The degree to which damage to the developing nervous system harms the mind and body varies enormously. Many disabilities are mild enough to allow those afflicted to eventually function independently in society. Others are not. Some infants, children, and adults die, others remain totally disabled, and an even larger population is partially disabled, functioning well below normal capacity throughout life.
This is a neural tube defect that occurs when the cephalic (head) end of the neural tube fails to close, usually between the 23rd and 26th days of pregnancy, resulting in the absence of a major portion of the brain, skull, and scalpThe scalp is the skin on your head from which hair grows. Scalping is the act of removing that skin, usually along with the hair, usually as a trophy of war. It is belived to have been a tradition in Plains Native Americans who may have been isolated from. Infants with this disorder are born without a forebrain - the largest part of the brain consisting mainly of the cerebrum, which is responsible for thinking and coordination. The remaining brain tissue is often exposed - not covered by bone or skin.
Infants born with anencephaly are usually blind, deaf, unconscious, and unable to feel pain. Although some individuals with anencephaly may be born with a rudimentary brainstem, which controls autonomic and regulatory function , the lack of a functioning cerebrum permanently rules out the possibility of ever gaining consciousness. Reflex actions such as respiration (breathing) and responses to sound or touch may occur. The disorder is one of the most common disorders of the fetal central nervous system. Approximately 1,000 to 2,000 American babies are born with anencephaly each year. 1 The disorder affects females more often than males. 1
There is no cure or standard treatment for anencephaly and the prognosis for affected individuals is poor. Most anencephalic babies do not survive birth. If the infant is not stillborn, then he or she will usually die within a few hours or days after birth. Anencephaly can often be diagnosed before birth through an ultrasound examination. The maternal serum alpha-fetoprotein (MSAFP) is useful for screening for neural tube defects such as spina bifida or anencephaly, but the gestational age of the fetus must be known for proper interpretation. Results from this test are frequently inaccurate and thus must be combined with other other tests to be properly used.
About 1000 anencephalic infants are born annually in the United States. About 95% of women who learn that they will have an anencephalic baby choose to have an abortion. Of the remaining 5%, about 55% are stillborn. The rest usually live only a few hours or days.
In almost all cases anencephalic infants are not aggressively resuscitated since there is zero chance of the infant ever achieving a conscious existence. Instead, the usual clinical practice is to offer hydration, nutrition and comfort measures and to “let nature take its course.” Artificial ventilation, surgery (to fix any co-existing congenital defects), and drug therapy (such as antibiotics) are usually regarded as being pointless. Some clinicians see no point in even providing nutrition and hydration, arguing that withdrawal of nutrition and hydration is morally and clinically appropriate in such cases.
The cause of anencephaly is unknown. Although it is believed that the mother's diet and vitamin intake may play a role, scientists agree that many other factors are also involved.
Recent studies have shown that the addition of folic acid to the diet of women of child-bearing age may significantly reduce, although not eliminate, the incidence of neural tube defects. Therefore, it is recommended that all women of child-bearing age consume 0.4 mg of folic acid daily, especially those attempting to conceive or who may possibly conceive. 1 It is foolhardy to wait until pregnancy has begun, since by the time a woman knows she is pregnant, the critical time for the formation of a neural tube defect has usually already passed. A physician may prescribe even higher dosages of folic acid for women who have previously had a pregnancy where a neural tube defect has occurred.
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