Clinical Optometry
Effect of Working Distance on Wesson Card Fixation Disparity and Its Clinical Predictors in Symptomatic Patients
By Thokozile Ingrid Metsing and Gloria Tsholofelo Tamenti.
Abstract
Aim
Fixation disparity (FD) is a sensitive marker of binocular vision stress and is often assessed in patients with asthenopia. Working distance alters accommodative and vergence demands. However, its effect on FD under routine clinical settings is not well established.
Purpose
To investigate the effect of working distance on FD measured using the Wesson fixation disparity card (WFDC) at 25 cm and 40 cm in symptomatic young adults, and to explore associations with selected binocular vision and accommodative measures.
