Factors contributing to long-term refractive error after cataract surgery

To evaluate factors that may influence the direction and extent of long-term refractive error after cataract surgery.This was a retrospective observational study conducted across two private practices in Sydney, NSW, Australia. The study population consisted of patients who underwent cataract phacoemulsification surgery between January 1 and December 31, 2018. Patients who received cataract surgery combined with another procedure were excluded. Demographic and biometric data including anterior chamber depth (ACD), keratometry, central corneal thickness, axial length (AL) and lens thickness were obtained pre-operatively. Spherical equivalent (SEQ) refraction was measured at 2 months and 3 years after surgery and compared with target refraction. Factors associated with refractive error were analyzed.This study included 221 eyes of 122 patients. A refractive error within 1.00 D was achieved in 217 eyes (98.2%) at 3 years post-operatively. Mean prediction error decreased significantly between 2 months and 3 years after surgery irrespective of whether eyes were more myopic (p 0.001) or more hypermetropic than predicted (p .0001). Pre-operative ACD and ACD-to-AL ratio were significantly associated with SEQ prediction error.After cataract surgery, refractive outcomes may be influenced by ACD and ACD-to-AL ratio. The pre-operative assessment of these risk factors may better inform IOL selection in individual patients. Prospective studies in a larger cohort are required.