RESUMO
Objective: To improve vision prognosis after ocular trauma by evaluating the indications for pars plana vitrectomy [PPV], the appropriate timing for surgery, and to find the key predictors of outcomes
Methods: This is a retrospective study. The medical charts of 48 patients presenting with blunt or penetrating eye injury and necessitating a PPV between 2009 and 2016 were reviewed. We studied the indications to operate and the timing of the surgery. The outcome depended on the comparison of the best corrected visual acuity [BCVA], evaluated according to the log-MAR scale before surgery and at 1 week and 6 months post surgery
Results: Forty-eight patients [42 males, 6 females] with mean age 32.4 +/- 17.3 years were recruited; 42 subjects had a penetrating eye injury out of which 21 presented with an intraocular foreign body [IOFB], and 6 had a blunt trauma. Mean preoperative BCVA was at 2.35 [logMAR], 2.25 at 1 week postoperatively, and 1.45 at 6 months. An epiretinal membrane [ERM] and drop of lens material in the vitreous were more likely to develop after blunt traumas. Initial assessment of retinal detachment [RD] was associated with the need to perform a 2[nd] vitrectomy [p = 0.011], poorer BCVA at 6 months [p = 0.001], and lower postoperative intraocular pressure [IOP] [p = 0.014]. Moreover, preoperative BCVA was worse in eyes with posterior scleral perforation [p = 0.008]. Shorter intervals between the trauma and the 1[st] PPV predicted a more frequent need to perform a 2[nd] vitrectomy [p = 0.045]. Patients who developed proliferative vitreoretinopathy [PVR] had poorer vision preoperatively and at 1-week post-op [p = 0.04 and p = 0.01 respectively]. The BCVA preoperatively, at 1 week, and at 6 months were positively correlated. Preoperative BCVA could be regarded as an important forecaster of outcome at 6 months [p = 0.009]; whereas the timing of PPV and of IOFB removal did not show any significant correlation with the final BCVA [r = 0.358, p = 0.132]
Discussion: The major indications for post-traumatic PPV are RD, IOFB, vitreous hemorrhage, retinal tear, ERM, and PVR. An initial RD resulted in poorer visual outcome at 6 months and increased the need for a 2[nd] PPV. Posterior scleral perforation caused inferior vision at presentation. The existence of a PVR lowered the vision initially and at 1 week post-op
Conclusion: The shorter the delay between the trauma and the 1[st] PPV, the more often a 2[nd] PPV was needed. The BCVA at the 3 points in time were positively correlated. Finally, the initial BCVA is a key predictor of outcome, contrarily to the timing of PPV or of the foreign body removal