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.