Opposite Clear Corneal Incisions versus Steep Meridian Incision Phacoemulsification for Correction of Pre-existing Astigmatism

Purpose: to compare the efficacy of adding an opposite clear corneal incision (occi) on the steep meridian versus performing surgery on the steep meridian alone during phacoemulsification in reducing pre-existing corneal astigmatism. methods: this randomized clinical trial was performed on 120 eyes with corneal astigmatism of > 1d undergoing phacoemulsification. incisions were made based on the type of astigmatism as follows: superior or superior + occi for with-the-rule and temporal or temporal + occi for against-the-rule astigmatism. patients were followed with refraction, keratometry and topography. statistical analysis was performed using one- and two-way anova and tukey-a test. results: mean corneal astigmatism was 1.82±0.86 d in the superior + occi group and 1.74±0.86 d in the temporal + occi group preoperatively which decreased to 1.31±0.59 (p=0.013) and 1.19±0.64 (p=0.009) postoperatively respectively. no significant change occurred in the amount of astigmatism in any of the two single incision groups. conclusion: paired occi on the steep axis is a useful technique to correct mild to moderate pre-existing astigmatism with no need for particular skill or additional instruments.