Presentation is highly variable and depends on the nature, size, and location of the intraocular foreign body (IOFB). Patients might be asymptomatic or complain of decreased vision, pain, floaters, and diplopia.
80.1.2 Exam Findings
Anterior segment examination may reveal conjunctival injection, subconjunctival hemorrhage, scleral laceration, focal lens opacities/capsular defects, self-sealing corneal or scleral wounds, and uveal prolapse. Iris transillumination defects and heterochromia, anisocoria, and a positive Seidel test may also be noted. Corneal deposits, anterior subcapsular cataracts, lens dislocation, and optic atrophy could be present especially with chronic iron-containing IOFBs. Gonioscopy can reveal occult IOFB in the angle and scleral depression may reveal in occult IOFB in the pars plana/anterior retina. Patient with occult IOFB and developing endophthalmitis may present with cells in the anterior chamber, hypopyon, and vitritis (▶ Fig. 80.1). Posterior examination can reveal retinal tears or detachments, commotio retinae, choroid rupture or detachment, sclopetaria, vitreous hemorrhage, or a posterior exit wound.
Fig. 80.1 Mixed hypopyon and hyphema in an eye noted to have pain after hammering without eye protection is suspicious for occult intraocular foreign body and associated endophthalmitis.
80.2 Key Diagnostic Tests and Findings
80.2.1 Plain X-Rays
Plain films are a quick and effective screening tool used to detect and localize radiopaque foreign bodies (▶ Fig. 80.2). Plain films can reveal small IOFBs that are sometimes missed by CT scans.
Fig. 80.2 Plain film X-ray may detect even a small metallic intraocular foreign body (arrow).
Can be used to visualize IOFBs in real time and from various angles. Ultrasonography may demonstrate radiolucent foreign bodies that are not seen on CT scans. High-resolution ultrasound biomicroscopy is useful for locating small, nonmetallic bodies in the angle, ciliary body, ciliary processes, and retrolental space (▶ Fig. 80.3, ▶ Fig. 80.4). Extreme care should be taken with the ultrasound probe in order to prevent extrusion of intraocular materials in case of a ruptured globe.
Fig. 80.3 B-scan ultrasound with a focal hyperechoic body (arrow) with associated shadowing is characteristic for metallic intraocular foreign bodies.