Purpose: To examine the difference in post-operative visual outcomes of cataract surgeries between a tertiary and secondary centre at Aravind Eye Hospitals in Tamil Nadu, India.
Methods: Our retrospective cross-sectional study analysed cataract surgeries at a secondary centre and its associated tertiary centre in 2021. Our main outcome measures were postoperative best corrected visual acuity (BCVA), spherical equivalent, and intraoperative and postoperative complications. Two-sample proportion tests, regression analyses, and logistic probability analyses were performed.
Results: The analysis of 32,302 cataract surgeries in 2021 of which 4,357 were performed at the secondary centre and 27,945 were performed at the tertiary centre showed that the tertiary centre operated on more advanced cataract condition (p<0.001) and had higher incidence of patients with ocular comorbidity (p<0.001). Intraoperative (p<0.001) and post-operative complication rates (p<0.001) were higher in the tertiary centre. The odds of effective outcomes (BCVA >=6/12) controlling for all covariates are poorer (p<0.0001) in the tertiary centre for both phacoemulsification (phaco) and manual small incision cataract surgeries (MSICS).
Conclusion: World Health Organization recommendations for the effective outcome of cataract surgery are met by both the tertiary and secondary centres, but the odds of effective outcomes in MSICS in the tertiary centre was lower after adjusting for all known factors. Further investigations of the causes of poor vision in MSICS in the tertiary centre are needed to improve the situation.