A comparative study of the gradient accommodative convergence/accommodation ratios obtained through +1.00ds and -1.00ds in primary school children

  • OU Amaechi
  • I Obiora
Keywords: Accommodation, Convergence, Gradient accommodative convergence/accommodation ratio, Induced phoria, von Graeffe technique.


The gradient accommodative convergence/accommodation ratios (AC/A ratios) of fifty healthy primary school children between the ages of 6-12 years determined through a+1.00 DS lens and through a -1.00DS lens were compared. This was done by measuring the induced phoria at near using the Von Graeffe technique and subsequently through a +1.00DS lens and a -100DS lens; the change in phoria brought about by the change in stimulus to accommodation gave the value of the gradientAC/Aratio. The mean AC/Aratio through +1.00DS was 3.4±1.4 and through -1.00DS was 4.2±2.0. The difference in the two A/C ratios was found to be significant (P<0.05). It is recommended that borderline patients should have their gradientAC/Aratiochecked through both lenses for more precise diagnosis and management

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eISSN: 0795-0039
print ISSN: 0795-0039