April 2009
Volume 50, Issue 13
ARVO Annual Meeting Abstract  |   April 2009
Relation Between Level of Astigmatism and Changes in Refractive and Corneal Astigmatism Over a Period of 2 Years
Author Affiliations & Notes
  • D. H. Messer
    Ophthalmology, University of Arizona, Tucson, Arizona
  • J. M. Miller
    Ophthalmology, University of Arizona, Tucson, Arizona
  • V. Dobson
    Ophthalmology, University of Arizona, Tucson, Arizona
  • E. M. Harvey
    Ophthalmology, University of Arizona, Tucson, Arizona
  • Footnotes
    Commercial Relationships  D.H. Messer, None; J.M. Miller, None; V. Dobson, None; E.M. Harvey, None.
  • Footnotes
    Support  National Institutes of Health/National Eye Institute (NIH/NEI) grants EY13153, unrestricted funds from Research to Prevent Blindness to the University of Arizona Department of Ophthalmology and Vision
Investigative Ophthalmology & Visual Science April 2009, Vol.50, 3969. doi:
  • Views
  • Share
  • Tools
    • Alerts
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      D. H. Messer, J. M. Miller, V. Dobson, E. M. Harvey; Relation Between Level of Astigmatism and Changes in Refractive and Corneal Astigmatism Over a Period of 2 Years. Invest. Ophthalmol. Vis. Sci. 2009;50(13):3969.

      Download citation file:

      © ARVO (1962-2015); The Authors (2016-present)

  • Supplements

Purpose: : To examine the relation between level of astigmatism and changes over 2 years in refractive and corneal astigmatism in preschool members of a Native American Tribe.

Methods: : Subjects were 87 children attending the Tohono O’odham Nation’s Head Start program, who had cycloplegic autorefraction and autokeratometry measurements taken with the Nikon Retinomax K-Plus and repeated at least 2 years later. Children were excluded if they had any ocular anomalies or if measurement confidence level was below 8 on the Retinomax at baseline or follow-up. For analysis, only data for the right eye of each subject were used. Subjects with more than 1.50D of refractive astigmatism (RA) at baseline were classified as having high astigmatism, while those with 1.50D or less RA were classified as having low astigmatism.

Results: : Mean age of subjects was 4.1 (0.51SD) years at baseline, and 6.5 (0.54SD) years at follow-up, with a range of follow-up from 2.0 to 2.7 years. Mean RA of the entire cohort did not significantly change from baseline (T1) to follow-up (T2), with only 16% of subjects having a change in refractive astigmatism of greater than 0.5D. However, in subjects with high astigmatism, mean RA increased over time, with 25% increasing by more than 0.5D and none decreasing by more than 0.5D. In low astigmats, mean RA decreased, with RA decreasing by more than 0.5D in 10% and only increasing by more than 0.50 in 1 subject. Similarly, mean corneal astigmatism (CA) did not significantly change for the population as a whole, but CA increased in high astigmats and decreased in low astigmats. See Table.

Conclusions: : Consistent with other studies, we found the power of both RA and CA to be reasonably stable over time. However, in children with high astigmatism, RA and CA were likely to increase over time, whereas children with low astigmatism were more likely have their astigmatism decrease.

Keywords: astigmatism • refractive error development 

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.