Refractive outcome of combined phacoemulsification and glaucoma surgery in patients of primary "open-angle glaucoma"

Introduction Glaucoma and cataracts are the leading causes of blindness worldwide. Treatment of either condition can influence the course of the other. Trabeculectomy induces changes to anterior chamber depth, axial length (AL), and corneal curvature, which could influence the accuracy of intraocular lens power calculations in combined surgery. Aim Assessment accuracy of intraocular lens calculation and refractive outcome after combined surgery versus cataract surgery (phacoemulsification) alone for coexisting cataract and glaucoma. Patients and methods Our study is a prospective nonrandomized comparative study of 43 consecutive patients (60 eyes) with cataract with coexisting glaucoma who had undergone phacotrabeculectomy (group 1) or phacoemulsification only (group 2). The biometry prediction error was determined for each case by the difference between the actual postoperative refraction and the preoperative predicted refraction in a spherical equivalent followed by comparative analysis of mean absolute refractive error, best-corrected visual acuity, and intraocular pressure (IOP) before and after surgery at 1, 3 months postoperatively. Results In both groups, best-corrected visual acuity was improved and IOP was decreased significantly. Mean absolute refractive error at 1, 3 months postoperatively was not significantly different between two groups (P>0.05) with more cylindrical changes and myopic shifts in group 1 due to high bleb, conjunctival or scleral suture, and changes in anterior chamber depth. Conclusion Phacotrabeculectomy may be an effective treatment with stable long-term outcomes of prediction error similar to phacoemulsification in patients with glaucoma. However, it is more effective in lowering IOP.