A comparative study of stereoacuity in patients with various grades of cataract and bilateral pseudophakia

Purpose: To compare the stereopsis in patients with various grades of cataract and bilateral pseudophakia. Methods: A cross-sectional observational study was conducted at a tertiary care center in South India from December 2016 to September 2018, wherein the stereoacuity of patients having bilateral senile cataract or bilateral pseudophakia, was measured using the Titmus Fly chart. Those with any form of squint, glaucoma or retinal pathology were excluded. The patients were divided into three groups based on the severity of cataract, determined by the Lens Opacification Classification System (LOCS)-III. Group 4 included those with bilateral pseudophakia. Statistical analysis was performed using one-way ANOVA test with post hoc analysis using the Bonferroni test, to study the difference of stereoacuity between the groups. Results: A total of 200 patients were evaluated. The mean stereoacuity was 65.2 ± 18.2, 114.8 ± 83.42, 402.4 ± 223.7 and 107.2 ± 71.68 arc seconds in groups 1, 2, 3 and 4, respectively (P < 0.001). The mean best corrected visual acuity (BCVA) in LogMAR units was 0.19 ± 0.15, 0.37 ± 0.24, 0.82 ± 0.26 and 0.14 ± 0.13 in groups 1, 2, 3 and 4, respectively (P = 0.01). On comparison between four groups, there was a generalised decrease in BCVA and stereoacuity with increasing grades of cataract except for group 4 which included the bilateral pseudophakics. On post hoc analysis to analyse intergroup variation a statistically significant difference in stereo acuity was noticed when group 3 was compared to other groups. Conclusion: Stereoacuity decreases with increasing grades of cataract. Better stereoacuity is seen in patients with bilateral pseudophakia when compared with high grades of cataract.