The most important consideration with any eye injury is the possibility of a penetrating globe injury with residual intraocular foreign body (IO FB). Patients may report FB sensation, but subtle presentations occur. Obtain a meticulous history about mechanism of injury (grinding or metal on metal).
Management and Disposition
For suspected subtle injury, a careful examination is required. Bedside ultrasound can be a useful adjunct and allows rapid identification of an IO FB. Care must be taken to avoid any pressure on the globe. A slit-lamp examination with Seidel test (copious amounts of fluorescein instilled and observed for streaming away from the site of perforation) may reveal a microperforation.
Maintain a high index of suspicion for penetrating globe injury, especially in mechanisms involving use of “metal on metal” such as grinding or hammering. A positive Seidel test demonstrates corneal microperforation.
If ocular penetration is suspected, a diligent search for a retained FB is indicated. Careful bedside ultrasound using a high-frequency transducer with copious gel (to avoid any pressure on the globe) can be used initially, but computed tomography (CT) is the diagnostic study of choice. Avoid magnetic resonance imaging (MRI), which should be saved for indeterminate results or when confirmation is required.
If using x-ray, obtain in both up and down gaze to assist localization of the metallic FB.
Anterior Chamber Foreign Body. A shard from a nail is seen embedded in the anterior chamber. A “teardrop” pupil is present, indicating perforation. (Photo contributor: Lawrence B. Stack, MD.)
Seidel Test. A positive Seidel test shows aqueous leaking through a corneal perforation while being observed with the slit lamp. (Photo contributor: Aaron Sobol, MD.)
Video 04-03: Seidel Test Strobol
A positive Seidel test shows aqueous leaking through a corneal perforation after swiping with concentrated fluorescein.
Video 04-04: Seidel Test LBS
A positive Seidel test shows aqueous leaking through a simulated corneal perforation after swiping with concentrated fluorescein.
Video 04-05: Seidel Test (Nichole Rice, PA-C)
Video 04-06: Paperclip Eyelid Retractor
Technique to make bedside eyelid retractors from a paperclip.
Intraocular Foreign Body. Hyperechoic foreign body clearly seen in the posterior vitreous. Note the layer of gel overlying the eyelid indicating “no pressure” technique. (Photo contributor: James K. Palma, MD.)
Intraocular Foreign Body (FB). Skull x-ray with intraocular metallic FB ...