The 49-year-old went to hospital suffering from a painful, reddened eye, loss of vision and a swollen eyelid.
Doctors at the ophthalmology department of Singleton Hospital in Swansea spotted a lesion on her cornea and initially thought it was caused by a herpes simplex infection.
But when the lesion was examined under a powerful microscope, they spotted a piece of glitter.
According to the case study, which was published in the BMJ Case Reports journal, after doctors spotted the shiny object in her eye, the patient remembered getting glitter in her eye when it rubbed off a Christmas card.
The glitter had formed into a clump causing a lesion that mimicked the symptoms of a herpes infection, the report said.
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