title: Optical treatment reduces amblyopia in astigmatic children who receive spectacles before kindergarten.
abstract: OBJECTIVE
  To examine the effect of spectacle correction of astigmatism during preschool on best-corrected recognition visual acuity (VA), grating VA, and meridional amblyopia (difference between acuity for vertical versus horizontal gratings) once the children reach kindergarten.
  
  
  METHODS
  Comparative case series.
  
  
  METHODS
  Seventy-three astigmatic (right eye > or =1.50 diopters [D] cylinder) Native American (Tohono O'odham) children 5 to 7 years of age. All had with-the-rule astigmatism. In 28 children, the astigmatism was simple myopic, compound myopic, or mixed (M/MA), and in 45 children, it was simple or compound hyperopic (HA).
  
  
  METHODS
  Thirty-nine children (Treated Group) had spectacle correction of refractive error, prescribed for full-time wear, in preschool (0.8-2.4 years before testing). Thirty-four children (Untreated Group) had no prior correction.
  
  
  METHODS
  Comparison of Treated versus Untreated Groups for mean best-corrected right-eye recognition VA, measured with the Early Treatment Diabetic Retinopathy Study (ETDRS) chart and the Lea Symbols chart, for grating VA, measured with modified Teller acuity card stimuli, and for meridional amblyopia, based on grating acuity results.
  
  
  RESULTS
  Mean ETDRS VA was significantly better in the Treated Group (20/37) than in the Untreated Group (20/48; P<0.003), but the difference between mean Lea Symbols VA in the Treated Group (20/33) and in the Untreated Group (20/38) was not significant. No significant Treated versus Untreated Group differences were found for either vertical or horizontal grating acuity. Meridional amblyopia differed between the M/MA group, which showed better acuity for vertical than for horizontal gratings, and the HA group, which showed better acuity for horizontal than for vertical gratings. However, in neither the M/MA group nor the HA group was there a significant difference in magnitude of meridional amblyopia in the Treated versus the Untreated Group.
  
  
  CONCLUSIONS
  Spectacle correction during the preschool years results in a significant improvement in best-corrected letter recognition acuity in astigmatic children by the time they reach kindergarten. However, grating acuity was not improved and magnitude of meridional amblyopia was not reduced in children who had received early spectacle correction.
  
  
  BACKGROUND
  Proprietary or commercial disclosure may be found after the references.
authors.affiliation: Department of Ophthalmology and Vision Science, University of Arizona, 655 N. Alvernon Way, Tucson, AZ 85711, USA. vdobson@eyes.arizona.edu
authors.forename: Velma
authors.initials: V
authors.lastname: Dobson
authors.forename: Candice E
authors.initials: CE
authors.lastname: Clifford-Donaldson
authors.forename: Tina K
authors.initials: TK
authors.lastname: Green
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Miller
authors.forename: Erin M
authors.initials: EM
authors.lastname: Harvey
mesh_terms: D000367:Age Factors; D000375:Aging / Q000502:physiology; D000550:Amblyopia / Q000208:ethnology / Q000503:physiopathology / Q000628:therapy*; D001130:Arizona; D001251:Astigmatism / Q000208:ethnology / Q000503:physiopathology / Q000628:therapy*; D002648:Child; D002675:Child, Preschool; D005139:Eyeglasses; D005260:Female; D006801:Humans; D007198:Indians, North American / Q000208:ethnology; D007223:Infant; D008297:Male; D011446:Prospective Studies; D013997:Time Factors; D014787:Vision Tests; D014792:Visual Acuity / Q000502:physiology