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VITRECTOMY FOR POSTERIOR SEGMENT INTRAOCULAR FOREIGN BODIES: VISUAL RESULTS AND PROGNOSTIC FACTORS

Purpose To evaluate the visual results and determine the prognostic factors after the removal of retained posterior segment intraocular foreign bodies (IOFBs) by pars plana vitrectomy. Methods A retrospective study of 40 consecutive cases of pars plana vitrectomy for the removal of IOFBs during the period of January 1991 to June 2000 was conducted. Association between visual outcome and various preoperative, operative, and postoperative variables was statistically analyzed. Results Of the 40 cases available for the study, the IOFBs could be removed in 36 eyes. Half the patients had removal of the IOFB within 14 days of the injury. Nineteen patients (47.5%) achieved a visual acuity of 20/40 or better. Postoperative retinal detachment occurred in 13 patients (32.5%). Poor visual outcome was found to be significantly associated with poor initial visual acuity and postoperative retinal detachment, whereas good visual outcome was significantly associated with the absence of lens injury and absence of postoperative retinal detachment. Conclusions Acceptable visual results could be achieved after the removal of posterior segment IOFBs by vitrectomy, despite a delay in surgery. Postoperative retinal detachment, poor initial visual acuity, and the absence of lens injury were the factors that played a significant role in determining the visual outcome.