title: Mass screening of children for strabismus or ametropia with two-flash photoskiascopy.
abstract: 169 non-selected 1-5 year-old children (338 eyes) were screened by two-flash photoskiascopy with an autofocus camera for strabismus, high anisometropia and high ametropias without cycloplegia. The photography was performed by nurses or technicians and the photographs were analyzed by an optician. The sensitivity of the method for the refractive errors was tested with an optical demonstration eye.
  
  
  RESULTS
  5 esotropias, 1 exotropia, 1 straight-eyed hypermetropic anisometropia of 4 diopters; 1 false positive high hyperopia (of +2.5 diopters) of both eyes. The examination of the photographs showed slight refractive errors in 33 cases (66 eyes; 19.5%): two of them of symmetrical myopia of -1.0 and -1.75 diopters and 31 of symmetrical hyperopia of +0.25 to +4.25 diopters in retinoscopy. 128 cases (256 eyes; 76%) were normal on the photographs. Of these, 37 non-selected cases (74 eyes) were checked clinically and were symmetrical cases of -1.0 to +3.25 diopters on retinoscopy. No false negative cases appeared among these control cases. 2,4% of the photographs failed technically or because of noncooperation of the children. Two-flash photoskiascopy, performed by technicians or nurses provides a valuable tool for mass screening of infants for strabismus and/or ametropia causing amblyopia.
mesh_terms: D002675:Child, Preschool; D005387:Finland; D006801:Humans; D007223:Infant; D008027:Light; D010775:Photic Stimulation; D010781:Photography / Q000295:instrumentation; D012030:Refractive Errors / Q000175:diagnosis / Q000453:epidemiology*; D013285:Strabismus / Q000175:diagnosis / Q000453:epidemiology*