Introduction: The Human race is supreme in hierarchy of animal kingdom by the acquisition of Binocular Single Vision 1 (BSV). It is important to have normal ocular muscle balance to have normal BSV. Any muscle balance disorder may lead to squint or amblyopia. Ocular muscle balance disorders shows an association with refractive error. Most of this research has focused on myopia. But hyperopia and astigmatism are also being examined in our study. 

Methodology: A Prospective study conducted over period of 1 year 300 subjects were included 150 were selected from OPD and rest 150 by screening 1875 students of various schools in Raichur District who had vision less than 6\6 or with 6\6 vision and as the no pic symptoms. Visual Acuity was measured. Fund us examination, Squint evaluation and Type of squint was noted. AC/A ratio was calculated. Binocular Vision was assessed. Those who needed treatment were treated by spectacles ororthoptic exercises. Correlation was made between ocular muscle imbalance and refraction.

Results: The prevalence of refractive errors was 8% with mallet of emaleratio 1.9:1. Highest were between 17-20 yrs. Heterophori as were the most common Type of ocular muscle balance disorders (80%) followed by heterotropias (20%). Exophoria was highest (52.8%) followed by esophoria (46.6%). Strong association was noted between myopia and exophoria 43 out of 60 (p=0.042). Cases of mixed astigmatism were observed having esophoria for near and exophoria for far. Significant association was noted between hypermetropia and convergent squint (67 out of 81).

Conclusion: Myopia is mainly associated with divergent squint, Hypermetropia with convergent squint. Mixed astigmatism associated with exophoria for far, esophoria fornear.