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INTRAOCULAR FOREIGN BODIES. Risk factors of visual loss: 1) M echanism of injury 2)Size of the IOFB 3) Location of the IOFB 4)Endophthalmitis 5) PVR. 25% of patients who sustained IOFB injury had final visual acuities of less than 20/200.
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Risk factors of visual loss: 1)Mechanism of injury 2)Size of the IOFB 3) Location of the IOFB 4)Endophthalmitis 5) PVR
25% of patients who sustained IOFB injury had final visual acuities of less than 20/200
PREOPERATIVE PREPARATION History Ophthalmic examination Appropriate neuroimaging Consideration of antimicrobials
HISTORY: Accurate history-taking with attention to the mechanism of injury (e.g. knife wound, explosive device, shotgun blast)
OPHTHALMIC EXAMINATION: Visual Acuity Endophthalmitis Globerupture Retinal detachment An afferent pupillary defect
NEUROIMAGING: CT SCAN B-scan ultrasonography Ultrasound biomicroscopy (UBM) X Ray MRI
PREOPERATIVE SYSTEMIC ANTIBIOTICS: Gram-positive organisms - coagulase-negative staphylococci - streptococci Gram-negative Fungal organisms
Third-generation fluoroquinolone: - levofloxacin Fourth-generation fluoroquinolone: - moxifloxacin
OPERATIVE CONSIDERATIONS Timing of surgery (delayed versus immediate) The route and instruments used for IOFB extraction The role of intraoperative antibiotics
Delayed versus immediate intraocular foreign body removal The presence or absence of clinical endophthalmitis The stability of the patient for an extended surgical procedure The availability of well trained operating room personnel
Advantages to immediate IOFB removal: 1) A decrease in the risk of endophthalmitis 2) A decrease in the rate of PVR 3) A single procedure under anesthesia with its attendant risks
Advantages to delayed IOFB removal: 1) Better integrity of the repaired laceration 2)Less severe anterior segment pathology (e.G. Resolution of corneal edema, hyphema resorption) 3)The presence of a PVD 4)Resorption of some V.H
ROUTE OF IOFB EXTRACTION Strategies for IOFB extraction at this point depend on the nature of the material and its size
intraocular magnet: Small (<1.0 mm) metallic ferromagnetic IOFBs
basket forceps: Medium-sized IOFBs (1.0–3.0 mm) Metallic Stone concrete
diamond-coated forceps: Larger IOFBs (3.0–5.0 mm) Glass fragments
POSTOPERATIVE CARE: endophthalmitis (5-7%) RD (6.3 to 36.8%) PVR ( 6.7 to 46% )
Inert foreign body: - Stone - Glass - Porcelain - Plastic - cilia
Reactive foreign body: - Zinc - Aluminum - Copper - iron
Zinc and aluminum: - Minimal inflammation - Encapsulated
SIDEROSIS Risk factors: - Content - Location
RPE cells Pars plana TM Corneal epithelium Lens epithelium Pupillary constrictor muscle
CLINICAL SIGNS: Nyctalopia ↓ VL Mydriasis Iris heterochromia Brown deposit beneath the ant. Lens capsule cataract
Peripheral retinal pigmentation diffuse retinal pigmentation Optic disc atrophy POAG
Abnormal ERG Increased a-Wave and normal b-Wave Diminishing b-Wave
IOFBs containing over 95% copper : severe , rapidly progressive purulent endoph-thamitis
IOFBs containing between 85 and 95% copper: visual loss→ deposition of copper in 1) descment΄s membrane 2) ant. Lens capsule 3) vit. Cavity 4)ILM
K-F ring Ant. Subcapsular sunflower cataract Greenish discoloration of the vitreous Greenish refractile deposits in the ILM
IOFBs containing less than 85 % copper usually produce no detectable change
CONCLUSIONS: IOFBs are common in open globe injuries Clinicians must remain suspicious of a possible IOFB in any traumatized eye