20 Simultaneous development of acute acquired concomitant esotropia in two siblings during the COVID-19 pandemic: a case report
A 5–year–old boy (sibling one) and his 11–year–old sister (sibling two) 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.
Sibling one had a moderate right esotropia, initially maintained straight by corneal light reflex. He measured 45/50 prism dioptres (Δ) base out at near and 45Δ base out at distance. Sibling two had esophoria which broke down into a right esotropia immediately on dissociation. The esotropia measured 30Δ base out at near and 20Δ base out at distance. At four month follow up, both siblings demonstrated a constant large angle esotropia (sibling one: 54Δ base out at near and 45Δ base out at distance, sibling two: 45Δ base out at near and 40/45Δ base out at distance).
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.
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.