ABSTRACT
Non-strabismic binocular vision dysfunction (NSBVD) are visual disorders that affect the person's binocular vision and visual outcome when performing near tasks causing eye strain, headache, and blurred vision. The purpose of this prospective study was to determine the vergence profile and distribution of Non-Stabismic Binocular Vision Dysfunctions and their relationship with age, gender and level of study among Optometry students. A total of seventy five (n=75) Optometry students participated in this study and the data classified as gender:male and female; age 15-30 with subclasses of 5 years: 15-20, 21-25, 26-30 ( 22.39 ± 3.19 years)and a level of study classification ranging from 100-600level were used in this study. A comprehensive binocular vision assessment was performed including: Case History, Visual Acuity, Cover Test ( alternate and cover/uncover), Von Graefe test for phoria, calculated AC/A ratio, Near point of convergence Test, Minus-lens to blur Amplitude of Accommodation Test, Negative and Positive Relative Accommodation Tests (NRA & PRA), Fusional Vergence Test(using the step vergence method) and Accommodative Facility Test (using flipper device). Of the 75 subjects that participated in this study, 32(42.67%) had no binocular vision dysfunction while 43(57.33%) had binocular vision dysfunctions which included Accommodative Infacility(n= 8; 10.68%), Accommodative Insufficiency (n=4; 5.33%), Accommodative Excess(n=5; 6.67%), Basic Exophoria (n=4; 5.33%),Convergence Excess (n=5; 6.67%), Convergence Insufficiency (n=12; 16%), Divergence excess (n=1; 1.33%) and Divergence Insufficiency (n=4; 5.33%) with Convergence insufficiency (16%) being the most occurring. The 600level class was most affected by non-strabismic binocular visiondysfunctions(n=16). Chi Square Test for Significance were used to determine the relatioshi between the distribution of NSBVD with level of study (p= 0.024), gender (p=0.108) and age (p=0.000). From thechi-square test there was a significant relationship between binocular dysfunction and age range and level of study (p<0.05). However, there was no significant relationship between gender and binocular dysfunction. In conclusion, Non-strabismic binocular vision dysfunctions (NSBVD) were common among Optometry students and may be influenced by some factors such as age and levelof study as regards to this study.
