Investigation of the child with permanent hearing impairment

SLITRK6 mutations cause myopia and deafness in humans and mice

“…For all sections, the digitized images were obtained by NDP slide scanner (Hamamatsu Photonics). Images were manually aligned using Free-D software (6), and the axial length was calculated from the x, y, and z coordinates of the retinal internal surface of the optic nerve entry point and the anterior pole, which was determined as the center of the external surface of cornea with largest diameter among a series of sections.…”

“…It affects more than 25% of adults in Western Europe and America, and its prevalence exceeds 70% in some urban areas of East Asia (2)(3)(4). High myopia, defined as refractive error greater than -6 or more diopters, affects approximately 1%-3% of the population (5) and is a significant risk factor for ocular comorbidity, including retinal detachment, macular degeneration, premature cataract, and glaucoma (1,6). Data from several study types suggest a strong genetic component to myopia.…”

“…Hearing loss is another common sensory disorder, with a prevalence of 1 in 1,000 at birth that almost doubles by 9 years of age (6,17). Although the incidence of hearing loss in individuals with myopia is unknown, the prevalence of ocular abnormalities in deaf children is high (17).…”

“…It is known that greater than 50% of permanent childhood hearing impairment in the developed world has a genetic etiology (6), and many syndromic forms of hearing loss have been described. Nonsyndromic hearing loss is similarly genetically heterogeneous, with greater than 150 loci and greater than 40 genes identified (6).…”

Etiología de la hipoacusia infantil.

“…Aunque hay numerosos estudios sobre la etiología de la hipoacusia permanente infantil, que han permitido conocer mejor las causas hereditarias y adquiridas, las diferencias culturales y metodológicas provocan que la proporción relativa de estas, sea muy variable de unas a otras publicaciones [2,10]. Cuando un neonato «no pasa» el cribado auditivo, no existe un algoritmo ideal, e incluso la forma de realizar el proceso de evaluación puede resultar controvertido [11]. En general se acepta que en el 50% de niños con hipoacusia permanente infantil el origen es hereditario (en un 70% no sindrómico), en un 25% adquirido y en otro 25% la causa es desconocida [12][13][14].…”