Horner Syndrome as a Rare Complication of Radiofrequency Tonsil Ablation.

Horner syndrome is a rare but likely underdiagnosed complication of tonsillary surgery. The authors report the case of a 2.5-year-old boy who developed miosis and mild ptosis after radiofrequency tonsil ablation surgery. Pharmacologic testing with apraclonidine 0.5% eye drops confirmed left Horner syndrome. This case highlights the close anatomical relationship between the tonsils and cervical sympathetic trunk and draws attention to the occurrence of Horner syndrome after tonsillectomy. [J Pediatr Ophthalmol Strabismus. 2018;55:e14-e15.].