Effect of spectacle correction on the progression of myopia in children--a literature review.

BACKGROUND: Methods used to attempt to control childhood myopia progression have included various types of spectacle correction. The most commonly studied technique has been the use of bifocal lenses.
METHODS: The literature on the effects of bifocals, undercorrection, and part-time wear of spectacles on the rate of myopia progression in children was reviewed.
RESULTS: The data available on undercorrection and part-time wear of spectacles is limited. There have been several studies on the effects of bifocals. Some studies reported no effect with bifocals, some studies reported reduced rates with bifocals, and some noted lower rates with bifocals may be associated with particular ocular or visual findings.
CONCLUSIONS: Critical analysis of the literature suggests that when the nearpoint phoria is eso, greater rates of progression occur, and that some degree of myopia control may be established by shifting the phoria into the normal range by spectacle corrections such as bifocals.