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49 R E T I N A L P H Y S I C I A N | J A N U A R Y / F E B R U A R Y 2 0 1 7 49 R E T I N A L P H Y S I C I A N . C O M | J A N U A R Y / F E B R U A R Y 2 0 1 7 and knowledge of this information is important in planning management for the patient. e history may also elucidate the material that the IOFB consists of, which is important because certain materials (eg, copper) can cause rapid and profound toxicity to the retina, while others (eg, vegetable matter) are more commonly associated with endophthalmi- tis. Clinical Exam It is important to ensure that other nonocular injuries associ- ated with the trauma have been assessed and treated appro- priately prior to initiating the ophthalmic exam. Many of these patients have concomitant head trauma or other trau- matic injuries. A complete exam of the uninvolved eye is also important. At presentation, the physician should check and docu- ment the visual acuity and relative afferent pupillary defect in the affected eye himself or herself. Intraocular pressure mea- surement should be deferred in patients with large lacera- tions. Other periocular trauma sequelae need to be evaluated, including retrobulbar hemorrhage, orbital fractures, ocular adnexa lacerations, and superficial foreign bodies. Some of these issues may need immediate attention (eg, retrobulbar hemorrhage), while others may require coordination of man- agement with other ophthalmic subspecialties in the operat- ing room (eg, canalicular lid laceration). Examination of the injured eye with slit lamp biomi- croscopy should be performed to evaluate the anterior seg- ment for lacerations in the conjunctiva, cornea, and/or sclera. Seidel testing should be performed to aid in identifying leaking wounds. e anterior chamber should be evaluated for depth, cell, hypopyon, fibrin, hyphema, and/or lens mate- rial. Peaked pupils should raise suspicion for OGIs in ocular trauma patients. Additionally, the iris should be examined for transillumination defects (Figure 2) prior to dilation, which may suggest a potential IOFB. Uveal tissue incarcerated in a laceration is a relative con- traindication to pupillary dilation. If uveal incarceration is not present, dilation should be performed to fully evaluate the lens and posterior segment. e lens capsule should be exam- ined for evidence of violation. Wrinkling of the lens capsule is suggestive of loss of nuclear or cortical material. e lens should also be examined for zonular dialysis and instability. IOFBs passing through the crystalline lens can cause a range of findings, from small focal cataractous changes to white cataracts, depending on the location of impact, size of IOFB, and time to presentation. e posterior segment should be evaluated for an IOFB (Figure 3), which can be located in the vitreous, ciliary body, retina, choroid, or the posterior sclera. e posterior segment should be evaluated for traumatic posterior segment pathol- ogy such as vitreous hemorrhage, commotion, retinal tears, retinal detachment (Figure 4) or dialysis, choroidal detach- ment, choroidal rupture, sclopetaria, and a posterior exit wound. Dense vitreous hemorrhage or cataracts can preclude visualization of the posterior segment, so imaging modalities might be needed to identify an IOFB. In eyes that do not permit a clear view of the posterior segment, the presence of a metallic IOFB can be confirmed using a metal detector. Imaging Imaging is a very important part of the workup of a patient with an OGI. Computed tomography (CT) scans are fast, widely available, and effective at detecting a wide range of foreign bodies. 6 in (1-mm) cuts with coronal (Figure 5), axial (Figure 6), and sagittal views are ideal to identify IOFBs and to assess the globe contour, site of posterior rup- ture, and any other cranial (eg, subarachnoid hemorrhage) or ophthalmic traumatic sequelae (eg, orbital fractures or ret- robulbar hemorrhage). Although CT is able to detect most IOFBs well, wood IOFBs are usually hypodense and may be mistaken for air or fat. 7 e presence of linear-appearing air should raise suspicion for a wood IOFB. Measuring the Hounsfield units of an IOFB identified on CT may provide some insight into its composition. 6 Figure 2. Slit lamp photo demonstrating iris transillumina- tion defect and traumatic cataract. Figure 3. Fundus photo demonstrating superotemporal metal intraocular foreign body embedded in the retina of the le eye.