European Journal of Molecular & Clinical Medicine

Aim: The aim of this study was to evaluate and compare the prevalence of Binocular Single Vision in cases with horizontal strabismus and normal individual.
Methods: This Prospective Observational study was conducted at Dr. D.Y. Patil Medical College, Pune from September 2020 to August 2022 which included 100 patients of horizontal strabismus and 100 healthy individuals
Results:  Out of 100 patients with horizontal strabismus, majority were male (52%) while in normal group, majority were female (55%). In strabismus, simultaneous macular perception was present in 76.19% of constant ET, 66.66% of alternating ET, 81.9% of constant XT and 91.6% of alternating XT compared to 100% in normal participants. In strabismus group, fusion was present in 33.33% of constant ET, 66.66% of alternating ET, 50.81% of constant XT and 91.6% of alternating XT compared to 100% in normal participants. In strabismus group, stereopsis was present in 33.33% of constant ET, 66.66% of alternating ET, 40.98% of constant XT and 66.66% of alternating XT compared to 93% in normal participants. In normal individuals, 100 % had gross stereopsis of 600 seconds of arc. In participants with strabismus, subjects with constant ET had gross stereopsis of 600,1000,1100 and 2000 seconds of arc in 19.04%, 4.76%, 9.52% and 66.66% of the participants respectively. Subjects with alternating ET had gross stereopsis of 600,1000,1100 and 2000 seconds of arc in 33.33%, 33.33%, 0.0% and 33.33% of the participants respectively. In the constant XT category, 22.95%, 8.19%, 9.83% and 59.01% of the participants had gross stereopsis of 600,1000,1100 and 2000 seconds of arc respectively. subjects with alternating XT had gross stereopsis of 600,1000,1100 and 2000 seconds of arc in 33.33%, 16.66%, 33.33% and 16.66% of the participants respectively. In normal individuals, 100% participants had their fine stereopsis between 20-100 seconds of arc. In participants with strabismus, subjects with constant ET had fine depth stereopsis between 20-100, 101-200, 201-400 and >400 seconds of arc in 19.04%, 9.52%, 14.28% and 57.14% of the participants respectively.
Conclusion:In our study, in the strabismic group, all grades of binocular single vision was observed to be reduced. SMP was observed to be present in majority participants in all group however it was observed to be reduced in the strabismus groups in the next two grades of BSV. It was also observed that Alternating type of Strabismus had better BSV when compared to the constant type. Thus, early detection of BSV anomalies paves way for early treatment and thus, preservation of BSV and better quality of life.