Corneal Foreign Body Removal

Excerpt

Patients with corneal abrasions and foreign bodies commonly present to emergency departments, urgent care centers, primary care, and eye care providers. The cornea is the most richly innervated tissue in the body. Patients with corneal foreign bodies may report multiple ocular symptoms, including pain, photophobia, decreased vision, copious tearing, discharge, blepharospasm, and conjunctival hyperemia. Typically the event has an acute, easily identified onset. Corneal foreign bodies are often acquired obscurely and suspected only after mild ocular symptoms persist. Patients frequently report that the foreign body was lodged in the eye while outside or coincidentally while working in the yard or on a home improvement project. Perhaps more worrisome are injuries that involve the high-velocity mechanics associated with hammering, grinding, and drilling metals.

The cornea is crucial for focusing light on the retina, allowing functional vision. As much as 67% of the eye's focusing power is derived from the cornea. A corneal injury will cause physical and functional discomfort. Subsequent corneal edema leads to photophobia and decreased visual acuity. Corneal scarring or irregularities may occur when objects are deeply embedded, resulting in significant vision disruption.

The cornea is essential for physically protecting the eye's internal structures from external elements. The dense, bony orbital structures encompassing the eye also help to protect the ocular surface. To a greater extent, the blinking of eyelids and lashes and the formation of reflex tears attenuate the accumulation of foreign matter on the cornea. Of utmost concern is the potential for intraocular penetration, which may lead to devastating consequences, including endophthalmitis or retinal detachment.

Corneal foreign bodies can be acquired during blunt or penetrating trauma. Associated traumatic injuries may include lid abrasions or tears, scleral tears, iridodialysis, traumatic mydriasis, relative afferent pupillary defects, anterior capsular tears, traumatic or rosette cataract, cortical matter disturbance, zonular dialysis, and vitreous prolapse. The posterior segment injuries can manifest as retinal tears or detachment, choroidal detachment, vitritis, and intermediate or panuveitis.