Ocular trauma due to intraocular foreign bodies remains a major cause of visual loss. Three-port pars plana vitrectomy is a standard procedure to remove intraocular foreign bodies. This operation may be complicated with retinal tear/detachment and proliferative vitreoretinopathy, which are poor prognostic factors. The purpose of our study was to assess whether different surgical approach based on the intraocular foreign body location influences the rate of postoperative complications and the final outcome.

107 patients, who underwent pars plana vitrectomy and removal of posterior segment intraocular foreign body were included in the study. All patients were divided in three groups intraoperatively according to the position of the intraocular foreign body in the posterior segment: In 23 patients (21%) the intraocular foreign body was entrapped in the vitreous cavity with no retina trauma (group A), in 48 patients (45%) it was floating into the vitreous after causing retinal trauma (group B) and in 36 patients (34%) it was embedded in the retina (group C).

Almost 45% of the cases achieved visual acuity better than 0.3 postoperatively. During vitrectomy removal of the vitreous cortex was achieved in 10 cases in group A (43.5%) and in 65 cases in groups B and C (77%). None of the cases in group A was complicated with proliferative vitreoretinopathy when the vitreous cortex was not removed, while 20% of cases were complicated with proliferative vitreoretinopathy, when the cortex was removed during vitrectomy. In groups B and C the rate of proliferative vitreoretinopathy was lower, when the vitreous cortex was removed, compared to the rate of proliferative vitreoretinopathy when the vitreous cortex was left (16% versus 36%).

Visual outcome remained poor when the retina had been directly traumatized by the intraocular foreign body, as in groups B and C. In group A the risk to develop proliferative vitreoretinopathy after vitrectomy was greater, when vitreous cortex was removed, while in groups B and C the risk was greater when vitreous cortex was not removed. Therefore, an attempt to remove vitreous cortex is suggested in cases where the intraocular foreign body has traumatized the retina, as in groups B and C.

This study indicates that intraoperative assessment of intraocular foreign body localization in the posterior segment contributes to an optimal surgical management and has also a prognostic value for such cases.