The effect of age on binocular vision normative values

Abstract

Purpose: To establish a relationship between age and horizontal heterophoria, horizontal fusional vergence amplitudes, and vergence facility testing. Methods: The sample consisted of 112 patients with a mean age of 39.8 ± 14.97 years (range: 18 to 65 years) and was composed of 61 women (54.5%) and 51 men (45.5%). The non-presbyopic group included patients 18 to 39 years old (n = 49) and the presbyopic group included patients 41 to 65 years old (n = 63). Binocular vision was studied by heterophoria horizontal magnitude (prism diopters [PD]), horizontal fusional vergences amplitudes (PD), and vergence facility testing (cycles per minute [cpm]) and quantified with a combination of 3 PD base-in and 12 PD base-out prisms. Results: Significant differences were obtained in near heterophoria with compensation (exophoria increased by 3.74 PD, t = 2.12, P <.05), distance positive fusional vergence (PFV) recovery (decreased by 2.86 PD, t = 3.03, P <.01), near PFV blur (decreased by 3.13 PD, t = 1.98, P =.05), near PFV break (decreased by 4.45 PD, t = 2.75, P <.01), near PFV recovery (decreased by 4.69 PD, t = 3.30, P <.01), and vergence facility testing (decreased by 2.63 PD, t = 2.77, P [removed]