Relationship between preoperative axial length and myopic shift over 3 years after congenital cataract surgery with primary intraocular lens implantation at the National Institute of Ophthalmology of Peru, 2007–2011

Objective To determine the relationship between the preoperative axial length and the myopic shift over 3 years after congenital cataract surgery with primary intraocular lens implantation and other related factors. Methods In this retrospective cohort study, the axial length was measured and assigned into 2 groups (>21.5 mm and ≤21.5 mm), visual axis obscuration, laterality of cataract, age of surgery and follow-up time were assessed and compared to the myopic shift. Results The mean myopic shift was 3.6 (standard deviation [SD]: 2.3) diopters (D) in all patients; 3.2 (3.3) and 3.9 (3.2) D for each group respectively (p=0.359). In unilateral cataracts the mean myopic shift was 6.3 D and in bilateral cases was 3.0 D (p=0.001). In bilateral cataracts, the shift was 2.6 D (SD: 2.0) and 3.4 D (SD: 1.8), respectively (p=0.098). Conclusion There was no relationship between the initial axial length and the myopic shift in all patients. Unilateral cataracts had a greater myopic shift over 3 years.