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The "O" sign--clue to a lost lens
Canadian Journal of Ophthalmology. Journal Canadien D'Ophtalmologie
|December 1, 1990
Summary
Lost hard contact lenses can erode into the upper eyelid, forming mass lesions. A specific conjunctival hole, the "O" sign, can indicate an embedded lens, aiding diagnosis.
Area of Science:
- Ophthalmology
- Ophthalmic Pathology
Background:
- Hard contact lens wear is common.
- Complications, though rare, can occur with improper use or loss of lenses.
- Delayed diagnosis of embedded foreign bodies can lead to significant tissue reaction.
Observation:
- Two patients presented with upper eyelid mass lesions after losing a hard contact lens.
- The lesions developed over approximately one year as the embedded lens eroded into the eyelid tissue.
- No external features initially suggested a lost contact lens.
Findings:
- A characteristic round hole in the conjunctiva overlying the embedded lens was observed in both patients.
- This finding, termed the "O" sign, was also identified in literature review of similar cases.
- The "O" sign is a key diagnostic indicator for embedded upper eyelid contact lenses.
Implications:
- The "O" sign is crucial for diagnosing deeply embedded hard contact lenses in the upper eyelid.
- Early recognition can prevent further complications and guide appropriate management.
- Ophthalmologists should consider this sign in cases of unexplained eyelid masses.