Hearing aids and services for developing countries

Of the estimated 250 million people around the world who have hearing loss and could benefit from having a hearing aid, two-thirds of them live in developing countries. In adults hearing loss affects their ability to obtain, perform, and keep a job. Throughout life, hearing loss causes people to be isolated and stigmatized. And while hearing loss is generally associated with aging, people in the developing world are more susceptible to this problem at a young age. Hearing loss in children affects language formation and cognitive and social development, and it can lead to lifelong disability. In spite of the pressing needs in the developing world, the supply of hearing aids fall far short of the demand. Of the hearing aids that are manufactured in the world, only a tiny proportion of them end up going to developing countries-only about one out of every eight units produced. Further, there is a major shortage of services in developing countries to fir hearing aids correctly, and with very few trained personnel to help that process. In response to this situation, the World Health Organization (WHO) has taken a number of steps. For example, representatives at a 1998 workshop organized by WHO and the Christian Blind Mission recommended that a small working group draw up guidelines for requirements for hearing aids and their accesories and services so that they would be appropriate and affordable for developing countries (AU)

Late diagnosis of a cerebellopontine angle tumour in a patient with trigeminal neuralgia

A rare case of trigeminal neuralgia caused by an ipsilateral acoustic neuroma is presented, with a review of the literature. The patient, a 58 year old female, had experienced deafness and tinnitus on the affected side for twenty-seven years, and had been investigated on two occasions several years earlier, prior to diagnosis of the neuroma. Trigeminal neuralgia was diagnosed fourteen years after onset of deafness, and was increasingly difficult to control. All three divisions of the trigeminal nerve were involved with sensorineural deficit over the affected side. The tumour was removed surgically but the patient was left with several neurological deficits.(AU)

Chronic meningococcaemia with sensorineural deafness in childhood

Chronic meningococcaemia is reported in a 10-year-old black male child. The relevant literature is reviewed. The clinical features, differential diagnosis and pathogenetic mechanisms of the condition are discussed (AU)

Studies on an isolated West Indies population: IV. Genetic study of hearing loss

Hearing troubles were found to be very frequent among inhabitants of French origin in a small Caribbean island. Segregation analysis of hearing loss was performed in 165 complete nuclear families and revealed that familial aggregation could be entirely explained by a single recessive gene with high frequency (0.40). Homozygous individuals for this gene would probably be more suscepticle to ototoxic agents than other individuals. High frequency of this gene may be due to a founder effect (AU)

Asyptomatic maternal rubella and congenital deafness

A total of 139 congenitally deaf children were studied. Of these 87 were found to be born in the year of 1961. This sharp rise in the incidence of congenital deafness was associated with an epidemic of German measles in the latter part of 1960 and early 1961. Only 20 of these 87 cases gave a definite history of maternal rubella. (AU)

Subclinical maternal rubella and congenital deafness

At present 40 percent of congenital deafness is inexplicable. The effect of rubella on the frequency of congenital deafness was studied five years after an epidemic of rubella in an island population. Of 87 congenitally deaf children born in 1961, the year after the epidemic, 86 had deafness as the only demonstrable congenital abnormality. Only 20 gave a history of first-trimester rubella. By modern classification the remaining 67 cases should be labelled as idiopathic congenital deafness having been ruled out. Serologic tests for rubella antibodies on 30 of the idiopathic deaf children were positive in 74 per cent, as compared to 30 per cent in a control group born within the same year. This study suggests asymptomatic rubella infection in the first trimester as an etiologic factor in congenital deafness. (AU)

Deafness in Jamaica: a pilot survey of a sample rural population

A pilot study of deafness in a random sample of a rural population of Jamaica showed that it was primarily attributable to sensorineural deafness. Apart from congenital deafness, two types occurred: (1) A deafness of sudden onset and having a stationary course; (2) Deafness of gradual onset and having a progressive course (AU)