Correlation between Worth Four Dot Test Results and Fusional Control in Intermittent Exotropia

Purpose: to compare the results of worth 4-dot test (wfdt) performed in dark and light, and at different distances, with fusional control in patients with intermittent exotropia (ixt). methods: dark and light wfdt was performed for new ixt subjects at different distances and the results were compared with level of office-based fusional control. results: fifty ixt patients including 17 male and 33 female subjects participated in the study. a significant difference (p<0.05) was observed between levels of home and office-based fusional control (p<0.05). a weak correlation was present between the results of wfdt and level of office-based fusional control; the highest agreement (kappa=0.088) was observed with dark wfdt performed at a distance of 4m. conclusion: evaluation of fusional state by far wfdt, especially in a dark room, shows modest correlation with office-based fusional control in ixt patients and can be used as an adjunct to more complex tests such as far stereoacuity