Traumatic eye injuries associated with intraocular foreign bodies (IOFBs) may result in devastating tissue disruption and severe visual loss depending on a number of factors including the time between trauma and IOFB extraction, initial visual acuity, entrance wound location, nature of IOFB, location of IOFB, preoperative retinal detachment, presence of intraocular hemorrhage, presence of endophthalmitis, use of lensectomy, use of an encircling band, type of endotamponade, and primary surgical repair combined with IOFB removal and the occurrence of postoperative complications. The aim of treatment in IOFB is to restore the ocular integrity and obtain a good visual outcome.
The majority (59–88 %) of IOFBs were located in the posterior segment and the best management is pars plana vitrectomy [24, 25]. Recent advances in vitreoretinal surgery and microsurgical techniques, using intraocular tamponade, have improved the success rate of pars plana vitrectomy (PPV) in the management of ocular injuries with retained posterior segment IOFB [11, 13]. The current strategy to reduce the rate of secondary complications comprises the operative removal of the vitreous, including all proliferative mediators, and stabilization of the retina without remaining traction. However, even advanced vitreoretinal surgery cannot prevent recurrent proliferative vitreoretinopathy (PVR) with deleterious long-term outcome including phthisis bulbi.
The 23-G vitrectomy allows for increased comfort, faster healing time, reduced corneal astigmatism, shorter surgical time, rapid postoperative and visual recoveries, less inflammation and less disruption to the conjunctiva than with 20-gauge procedures [26, 27]. The smaller port size of the instruments increases the ability to remove vitreous with very little traction or to remove epiretinal membranes without risking incarceration of the retina in the port.
Currently, although many vitreoretinal surgeons have accepted small gauge vitrectomy for vitreoretinal diseases, usage of small gauge PPV is not widespread in the management of ocular injuries with retained posterior segment IOFB. There are a few published studies in the literature for small gauge vitrectomy and posterior segment IOFB removal. Kiss et al. reported that anatomic and visual outcomes of transconjunctival 25-gauge PPV for treatment of IOFB removal . Kunikata et al. showed the usage of 25-Gauge micro incision vitrectomy surgery for removal of large IOFB in two cases . However, there are few published studies on outcomes of 23-G PPV for posterior segment IOFBs .
In this present study, we evaluated the efficacy and safety of 23-gauge PPV for treatment of retained posterior segment IOFB. The mean BCVA improved significantly from 1.44 LogMAR to 0,78 LogMAR (p = 0,007) and an anatomic success was obtained in 97.2 % of eyes.
Traumatic cataract associated with IOFB is a common problem, which ranges from 44 to 66 % . In our study, traumatic cataract was seen in 55.6 % of eyes. A combined vitreoretinal and cataract surgery was performed in these cases.
Retinal detachment associated with IOFB is the main reason for visual loss following intraocular foreign body injuries involving the posterior segment. Despite surgical advances in managing posterior segment, intraocular foreign body injuries, preoperative, and postoperative retinal detachments remain a frequent and devastating secondary complication. Rhegmatogenous retinal detachment after penetrating trauma is rapidly and severely complicated by proliferative vitreoretinopathy, and proliferative vitreoretinopathy was the reason for failure of retinal detachment surgery in the eyes that developed rhegmatogenous retinal detachment in other series [32, 33]. The rate of retinal detachment associated with IOFB ranged from 16 to 47 % [4, 21, 34]. In our study, preoperative retinal detachment was seen 16.6 % of eyes. Also, postoperative retinal detachments developed in two eyes (5.5 %). Scleral entrance and foreign bodies larger than 3 mm were associated with retinal detachment.
Visual loss may be associated with the timing of IOFB removal, scleral entrance of IOFB, preoperative visual acuity, and secondary complications such as endophthalmitis, rhegmatogenous retinal detachment (RD), intraocular pressure elavation, cataract, inflammation, or foreign body toxicity. In a study, early surgery, good preoperative visual acuity, and small IOFB were indicated as good prognostic factors [4, 35]. Our study showed that good preoperative visual acuity associated with good prognosis, retinal detachment and endophthalmitis were associated with worse prognosis, and IOFB size, location, and entrance were not associated with prognosis.
The size of the IOFB is one factor associated with postoperative anatomical and visual outcomes. The increasing size of IOFB was significantly associated with a poor visual outcomes . The size of IOFB has been found to be a significant predictive factor of poor visual outcome in the previous studies of IOFB removal . A large IOFB is more likely to inflict severe damage at the time of entry because of its higher kinetic energy, leading to a poor visual prognosis . However, when considering similar sized IOFBs, no particular association between the visual outcome and the size of IOFB in eyes that developed endophthalmitis was found in our study. Despite these discrepancies in the influence in IOFB size on functional and anatomic outcomes, however, IOFB size does play a role in operative decision-making, and should be noted carefully. In our study, the mean size of IOFB was 5.63 mm. For removal of IOFB, a 23-G sclerotomy was expanded like the shape of the T or L letters.
Our study had some limitations. Our follow-up period was 9.4 ± 6.4 months; longer follow up periods were necessary for more precise results on IOFB complications. Lack of the images for the preoperative and postoperative periods of the cases were our other main limitation in this paper. Nevertheless, our study is the first investigating the 23-G PPV with IOFBs.