Simultaneous Development of Acute Acquired Concomitant Esotropia in Two Siblings during the COVID-19 Pandemic: A Case Report

AIM: To report a case of two siblings who near–simultaneously developed a large angle concomitant esotropia during the COVID–19 pandemic, and to describe their treatment and outcomes. METHOD: A 5–year–old boy and his 11–year–old sister were presented to the hospital eye service in early 2021, having both developed acute–onset large angle esotropia within three months of each other. Neither had any significant past medical, ophthalmic, or family history. The siblings lived in the same household, and both experienced lifestyle changes as a result of the UK lockdown in response to COVID–19. RESULTS: Each sibling was treated with right medial rectus recession (5.5 mm) and right lateral rectus resection (7 mm), and at a three–month follow–up, both were minimally esophoric with restored binocularity. CONCLUSION: The unusual and abrupt changes in lifestyle imposed by the COVID–19 pandemic highlight the likelihood of an environmental aetiology for some forms of esotropia and raise the possibility that extended screen time may be a contributory factor.