Amaechi, O. U. and Obiora, I.
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 was 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 gradient AC/A ratio. The mean AC/A ratio through +1.00DS was 3.4±1.4 and through -1.00DS was 4.2±2.0. The difference between the two A/C ratios was found to be significant (P<0.05). It is recommended that borderline patients should have their gradient AC/Aratiochecked through both lenses for more precise diagnosis and management.
Keywords: Accommodation, Convergence, Gradient accommodative convergence/accommodation ratio, Induced phoria, von Graeffe technique.