Clinical Characteristics of Intermittent Exotropia

Abstract

Purpose: To examine the clinical characteristics of intermittent exotropia in subjects of 6 to 30 years 
old. 
Design: A cross sectional study 
Methods: A study was conducted at Binocular Vision Clinic in Hospital Universiti Kebangsaan 
Malaysia (HUKM) which involved 30 subjects in intermittent exotropia group and 30 subjects from 
control group. Non-probability sampling was applied. The ocular parameters included refractive error, 
measurement of visual acuity for distance and near, assessment of ocular deviation at near and 
distance employing the cover test and prism cover test, measurement of negative and positive fusional 
reserves using a prism bar and measurement of amplitude of accommodation using RAF rule. Other 
than that the ocular motility at nine positions of gaze was also examined, including assessment of 
binocularly by means of a TNO test for near vision and a Worth-4-Dots test for distant vision. 
Independent t test and Mann whitney test were used in data analysis. 
Results: There were significant differences for visual acuity at 6m, amplitude of accommodation, 
vergence for 6m and 40cm for prism cover test, stereopsis and near point convergences (NPC) 
between intermittent exotropia and control groups. 
Conclusion: The findings concluded that female are the most common in both groups’ intermittent 
exotropia subjects and the non squint subjects and the majority is Malay subjects.