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Abstract - 105 - SUM MAR Y Congenital sensorineural deafness forms one of the problems that face the otologist as it is difficult to manage and has its grave sequelae which must be prevented. It may arise as a result of genetic disorders or teratogenic factors. The teratogenic factors include prenatal infections with rubella, cytomegalovirus, measles,chicken pox, toxoplasmosis and syphilis, ototoxic drugs taken during pregnancy such as streptomycin, kanamycin, gentamycin, ethacrynic acid and thalidomide and perinatal teratogenic factors such as cerebral anoxia, birth trauma, low, birth weight and hyperbi1irubinaemia. Genetic hearing loss represents 50 percent of all cases of sensorineural hearing loss and this population will become increasingly larger as other causes come under control. Sensorineural hearing loss may occur as an isolated anomaly where the diagnosis can be made by its mode of transmissior.4age of onset, stability or progression and audiometric findings or it may occur as a part of syndromes which can be distinguished by their associated abnormalities such as Penderd’s and Small’s syndromes. - 106 - For identifying dea~n~s in newborn infants; there are two basic steps; first the application of high risk register, and second, the actual hearing screening tests. The medical diagnostic work up of the child with hereditary deafness should go through, history, general physical examination, head and neck examination, routine laboratory tests and otoscopic examination. Hearing screening tests are described in relation to different age groups: from 0 - 4 months from 5 - 15 months from 15 - 30 mOnths from 30 months - 5 years School age child. Hearing screening tests include sound field behavioural observation audiometery, conditional orientation reflex, visual reinforcement audiometery, attempt identification of body parts, and simple pictures (through air and bone conduction). A.C., B.C. pure tones, speech detection level, and speech discrimination level. Electroacoustic impedance and stapedius reflex measurements are important objective tools in the diagnosis and have several values. - 107 - Laboratory tests for evaluation of congenital sensorineural hearing loss are important especially in certain syndromes as Hurler’s syndrome. Radiographic investigations including plain films, poly tomography and high resolution C.T. scanning are of great value in evaluating a case of congenital sensorineural deafness. Management of a child having congenital sensorineural deafness aims ·for the development of speech and language which is the main problem. Several factors are cons;ldered in management including counseling of parents of the deaf child, sensory aids, and surgical interference. Counseling of the p~fents of the deaf child is a very important factor as they supposed to spend a great deal of the day with him and can have a good part in the plan of his management. By far hearing aids are the most beneficial tools in speech and language development. The early,appropriate and supervised use of a hearing aid is the single, mostirnportant therapeutic way to assist the hearing impaired child whose condition is not surgically or medically correctable. Surgical interference is restricted to a very small number of cases and it aims only to prevent further deterioration of the level of hearing. |