DR.MOHAMMED IRFAN SHEIKHabout 1 year ago

External Ophthalmomyiasis Due to Oestrus ovis

A 53-year-old man presented to the emergency department with itching in the right eye that had been present for several hours. Earlier that day, while gardening near a horse and sheep farm, he had felt something enter his right eye. At presentation, the visual acuity was 20/20 in each eye. Examination of his right eye showed conjunctival hyperemia without purulence and a normal anterior chamber and fundus. More than a dozen mobile, translucent larvae were observed on the cornea, bulbar conjunctiva, and upper and lower conjunctival fornices (Panel A, and see video). There was no intraocular or retinal involvement. A diagnosis of external ophthalmomyiasis — an infestation of the outer structures of the eye by fly larvae — was made. Curative treatment involves mechanical removal of the organisms. In this case, the larvae were removed with forceps and identified as Oestrus ovis, also known as the sheep bot fly, which had presumably flown into the patient’s eye and deposited the larvae (Panel B). Because the larvae were numerous and can cause superficial corneal abrasions with their cephalic oral hooks and body spicules, the patient was treated with prophylactic topical antibiotic agents. At follow-up 10 days later, his symptoms had resolved.