Conjunctival Foreign Body
Foreign bodies on the conjunctival surface are best recognized with slit-lamp examination. Foreign bodies can lodge in the cul-de-sac, or they may be located on the palpebral conjunctival surface of the upper eyelid (Fig 14-23). When a patient reports an ocular foreign-body sensation, topical fluorescein should be instilled to check for the fine, vertical, linear corneal abrasions characteristic of retained foreign bodies on the eyelid margin or superior tarsal plate (Fig 14-24). Foreign matter embedded in tissue can be removed with a sterile, disposable hypodermic needle. Glass particles, cactus spines, and insect hairs are often difficult to see, but a careful search of the cul-de-sac with high magnification aids in identification and removal. These foreign bodies may be removed with finetipped jeweler’s forceps or a blunt spatula. If a foreign body is suspected but not seen, the cul-de-sac should be irrigated and wiped with a cotton-tipped applicator moistened with topical anesthetic. Double eversion of the eyelid with a Desmarres retractor or a bent paper clip may be necessary to allow the examiner to effectively search the entire arc of the superior cul-de-sac (see Fig 14-9).
If no foreign body is found after a thorough examination, the next step is copious irrigation to cleanse the fornix. This procedure should then be repeated for both the upper and lower eyelids. Gunpowder or carbon fragments, such as those that may be embedded in the conjunctiva by a blast injury, should be removed if possible, but can be well tolerated in the substantia propria.
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.