Are binocular alignment and convergence amplitude different between phakic and pseudophakic older patients?

Purpose: To compare the binocular alignment status and convergence amplitude between phakic and pseudophakic older adults. Methods: The present report is a part of the Tehran Geriatric Eye Study (TGES), a population-based study performed on the elderly population above 60 years of age in Tehran, Iran. All study participants were transferred to the examination site and underwent complete ocular examinations including the measurement of uncorrected and best-corrected visual acuity, objective and subjective refraction, unilateral and alternating cover tests, and slit-lamp biomicroscopy. Results: Of 3791 invitees, 3310 participated in the TGES (response rate: 87.3%). After applying the exclusion criteria, the data of 1969 individuals were analyzed for this report. The mean of far exophoria, far esophoria, near exophoria, and near esophoria was 5.09 +/- 3.66, 8.20 +/- 9.60, 6.94 +/- 3.69, 7.00 +/- 5.83 prism diopter in phakic and 5.15 +/- 2.43, 6.50 +/- 5.80, 7.77 +/- 4.00, 4.75 +/- 1.50 prism diopter in pseudophakic individuals, respectively. The mean of far exotropia, far esotropia, near exotropia, and near esotropia was 14.92 +/- 9.49, 22.00 +/- 13.86, 15.09 +/- 7.20, 21.33 +/- 14.47 prism diopter in phakic and 19.67 +/- 22.5, 8.00 +/- 0, 17.36 +/- 7.55, 17.36 +/- 7.55, 0 prism diopter in pseudophakic individuals, respectively. Near exophoria (P = .003) was significantly higher in pseudophakic than in phakic participants after controlling the effects of age, sex, body mass index, diabetes, and hypertension. The mean near point of convergence was 7.94 +/- 3.27 cm in phakic and 7.99 +/- 3.3 cm in pseudophakic participants. Conclusion: Near exophoria was significantly higher in pseudophakic compared to phakic individuals while other deviations and near point of convergence were not significantly different between phakic and pseudophakic groups.