RESUMO
The Welch Allyn AudioScope is a new screening instrument that allows both audiometric testing at 500, 1000, 2000, and 4000 Hz at 25 dB hearing level and otoscopic examination. Sixty-eight patients between 3 and 9 years of age with normal hearing or a variety of hearing losses comprised the study population. Immediately after receiving an audiologic evaluation the subjects were screened with a traditional screening audiometer and two examinations with the AudioScope, performed in a clinic examining room by pediatricians and nurse practitioners unaware of the children's hearing status. The AudioScope was as accurate as traditional hearing screening in identifying children with normal hearing and those with hearing loss. Log-linear modeling demonstrated that the results of AudioScope testing were similar to those of traditional hearing screening. However, the false positive rate was higher at 500 Hz for the first AudioScope examination, suggesting the need for two AudioScope tests. The AudioScope was quick and easy to use, nonthreatening to the subjects, less expensive than a pure-tone screening audiometer, and does not require a sound-treated room.
Assuntos
Transtornos da Audição/diagnóstico , Testes Auditivos/instrumentação , Audiometria , Criança , Pré-Escolar , Estudos de Avaliação como Assunto , Reações Falso-Negativas , Reações Falso-Positivas , Audição , Humanos , Estatística como AssuntoRESUMO
Cumulative lead exposure in 193 inner-city Black children was evaluated by measuring lead concentrations in the primary dentine and the circumpulpal dentine of their deciduous teeth. The children's dentine lead levels were comparable to those reported in population studies of low-income children living in inner-city areas. The results of neuropsychological tests administered at age 7 were available for children in the sample; we performed further neuropsychological assessments when their teeth were shed (10-14 yr of age). Higher dentine lead concentrations were associated with deficits in neuropsychological test performance at both testings, with performance abilities more strongly affected than verbal abilities. Moreover, the negative effects of lead on neuropsychological functioning were more evident when lead concentrations in circumpulpal dentine, rather than in primary dentine, was used as the index of lead exposure. Based on this finding, we suggest that circumpulpal dentine and primary dentine should be assayed separately in order to yield a more sensitive estimate of exposure to lead.
RESUMO
Teeth were collected from populations differing in their degree of industrialization and from prehistoric populations. Lead analysis of dentine revealed that in contemporary teeth the lead level was related to the degree of industrialization and that in prehistoric teeth very low concentrations of lead were present. Because tooth lead reflects the body burden of lead, this result suggested that the prehistoric populations and modern nonindustrial populations were exposed to environments low in lead. Teeth from a contemporary population of nonindustrialized Indians of the Lacandon forest in Mexico contain lead in concentrations comparable with those of the prehistoric populations. Comparison of the Indian teeth with teeth from a modern industrial population reveals a 45-fold difference in median tooth lead level. This finding lends support to the hypothesis that high levels of urban lead pollution result in elevated body burdens of lead.