The Frequency of Occurrence of Strabismus in Infants Post Lensectomy

Purpose To identify and characterize incident cases of strabismus and interocular visual acuity among infants post lensectomy for congenital cataract. Method This was a single-centre retrospective chart review of all children aged less than 12 months who underwent lensectomy from 1st January 2014 to 1st January 2021. Cases were identified from theatre coding and electronic medical records. Cases with strabismus prior to cataract surgery were excluded. Results Seventy-five children (114 aphakic eyes) were included, 36 (48%) had unilateral cataract surgery while 39 (52%) had bilateral. The mean age at the time of cataract surgery was 3.0±2.5 months (range 1 - 10 months). The mean follow-up period was 41.2±22.8 months (range 2 -72 months). Nineteen out of 75 patients (25%) developed strabismus, most of whom (18 cases) had unilateral surgery. Out of the 19 strabismus cases recorded, esotropia was reported in 74% of the cases, followed by exotropia -16%, while esotropia associated with dissociated vertical deviation (DVD) and esotropia associated with inferior oblique each made up 5% of the population. Most children who developed strabismus [17 patients (89.5%)] had lensectomy prior to 6 months of age. A significant difference of 0.65 logMAR was recorded in the interocular visual acuity (IOVA) difference between the strabismic and non-strabismic groups, and the unilateral and bilateral lensectomy groups. Conclusion Strabismus, most commonly esotropia, is common after congenital lensectomy, particularly in those children who underwent unilateral cataract surgery, and in those less than 6 months of age. Monitoring IOVA and strabismus incidence post-cataract surgery is crucial for early intervention and amblyopia prevention.